Concrete- Check
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Concrete-Check
User Manual
Version 12
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Concrete-Check - User Manual
Update Sheet for Version 12
April 2009
Modifications:
The following modifications have been incorporated:
Section Page(s) Update/Addition Explanation
All All Update Conversion to Microsoft® Word format
3.5 3-03 Update Unsupported platforms removed
3.6 3-04, 3-05 Update Unsupported platforms removed
Ch 5 5-78 Update Add note on line segments to
STEEL-S-N-CURVE command
Ch 5 5-80 Addition Add STRENGTH-CRITERIA command
Ch 5 5-96 Update Add note on NS3473 to
WATERTIGHTNESS command
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Concrete-Check – User Manual Table of Contents
TABLE OF CONTENTS
1. INTRODUCTION............................................................................................................................................1-1
2. PROGRAM DESCRIPTION ...........................................................................................................................2-1
2.1 OVERVIEW OF THE CONCRETE SUITE............................................................................................2-1
2.2 METHODS OF SLAB ANALYSIS .........................................................................................................2-2
2.3 ULTIMATE STRENGTH CHECKS .......................................................................................................2-3
2.4 SERVICEABILITY CHECKS .................................................................................................................2-4
2.5 FATIGUE CHECKS ................................................................................................................................2-4
2.6 IMPLOSION AND PANEL STABILITY CHECKS...............................................................................2-5
2.7 HANDLING OF PRESTRESS LOADS ..................................................................................................2-5
2.8 DEFORMATION LOADS .......................................................................................................................2-7
2.9 PROGRAM LIMITATIONS....................................................................................................................2-8
3. RUNNING THE PROGRAM ..........................................................................................................................3-1
3.1 INTRODUCTION ....................................................................................................................................3-1
3.2 COMMAND LINE...................................................................................................................................3-1
3.3 CHANGED INPUT STREAMS ..............................................................................................................3-2
3.4 INPUT AND OUTPUT CHANNELS ......................................................................................................3-2
3.5 BATCH FILES .........................................................................................................................................3-2
4. DATA PREPARATION ..................................................................................................................................4-1
4.1 INTRODUCTION ....................................................................................................................................4-1
4.2 UNITS ......................................................................................................................................................4-1
4.3 SIGN CONVENTION AND SLAB AXES .............................................................................................4-2
4.4 FORMAT OF INSTRUCTIONS .............................................................................................................4-2
4.5 ABBREVIATION OF INSTRUCTIONS ................................................................................................4-2
4.6 CONTINUATION LINES .......................................................................................................................4-3
4.7 COMMENT LINES .................................................................................................................................4-3
4.8 SUMMARY FILE COMMENTS ............................................................................................................4-4
4.9 RECOVERY OF ENVELOPES...............................................................................................................4-4
4.10 SECTION DEFINITION .........................................................................................................................4-6
5. COMMAND FORMATS .................................................................................................................................5-1
Appendix - A Summary of Commands ..............................................................................................................A-1
A.1 INTRODUCTION ...................................................................................................................................A-1
A.2 RUN CONTROL COMMANDS ............................................................................................................A-1
A.3 NODE, SET AND LOCATION SELECTION .......................................................................................A-1
A.4 BASIC DATA COMMANDS .................................................................................................................A-2
A.5 ULTIMATE & SERVICEABILITY LIMIT STATES ...........................................................................A-2
A.6 FATIGUE LIMIT STATES ....................................................................................................................A-3
A.7 IMPLOSION CHECKS ..........................................................................................................................A-3
A.8 PANEL STABILITY CHECKS ..............................................................................................................A-3
A.9 FILE HANDLING ..................................................................................................................................A-4
Appendix - B Sample Output ............................................................................................................................. B-1
B.1 DATA ECHO AND PRINTING ............................................................................................................. B-1
B.2 CODE CHECK OUTPUT ....................................................................................................................... B-1
B.3 PLOT OUTPUT ...................................................................................................................................... B-2
Appendix - C SESAM FE Interface ................................................................................................................... C-1
C.1 INTRODUCTION ................................................................................................................................... C-1
C.2 AVAILABLE ELEMENT TYPES ......................................................................................................... C-1
C.3 STRESS EXTRACTION ........................................................................................................................ C-2
C.4 SYSTEM DEPENDENT COMMANDS ................................................................................................ C-2
C.5 FILE HANDLING .................................................................................................................................. C-4
Appendix - D ASAS FE Interface ......................................................................................................................D-5
D.1 INTRODUCTION ...................................................................................................................................D-5
D.2 AVAILABLE ELEMENT TYPES .........................................................................................................D-5
D.3 STRESS EXTRACTION ........................................................................................................................D-6
D.4 SYSTEM DEPENDENT COMMANDS ................................................................................................D-6
D.5 FILE HANDLING ..................................................................................................................................D-7
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Concrete-Check – User Manual Introduction
1. INTRODUCTION
CONCRETE-CHECK is part of the CONCRETE suite of programs that also includes
CONCRETE-ENVELOPE and CONCRETE-PLOT. The suite is designed to allow the
user to rapidly check concrete structures against codes of practice such as BS8110,
BS5400, Det norske Veritas (DnV) Rules, Norwegian Standards (NS3473), the
CEB/FIP model code (MC78) and Department of Energy (D.En) guidelines to assess
their strength, serviceability and fatigue performance.
CONCRETE-CHECK performs the following tasks, it:
− allows the user to select areas of an existing FE model to check given results
extracted by CONCRETE-ENVELOPE or available on backing file directly from
the FE System;
− optionally runs in a stand-alone mode letting the user input geometry and loads
directly;
− performs ultimate limit state calculations to determine the strength of
reinforced/prestressed concrete under selected loads. These calculations may be
performed using simple strip theory to BS8110, or by a more rigorous layered
approach under general loading. A simple redesign facility is also available.
− performs shear cheeks to a variety of the above codes;
− performs serviceability limit state crack width stress check and watertightness
calculations given the above loading and methods;
− performs deterministic cumulative damage calculations based on Miner's
hypothesis for the fatigue limit state;
− stores the results of the above checks to file for subsequent plotting via
CONCRETE-PLOT;
− performs implosion calculations in accordance with DnV and other rules;
− performs panel stability calculations for flat panels under combined loading.
This manual should be read in conjunction with the CONCRETE suite Theory Manual,
which contains details of the calculations, algorithms and references used in the
program. The CONCRETE-ENVELOPE and CONCRETE-PLOT User Manuals will
also be of assistance. Instructions to new users and examples of program use may be
found in the Application Manual.
The CONCRETE suite can interface with FE analysis programs, currently ASAS and
SESAM. Both CONCRETE-ENVELOPE and CONCRETE-CHECK can be configured
to run with any one of these programs. CONCRETE-CHECK can also be set up to run
only in stand-alone mode Details of the interface to FE systems for which this version
of the program is available may be found in appendices at the end of this manual.
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Concrete-Check – User Manual Introduction
When in use as an FE system post-processor, the CONCRETE programs can be
configured to process FE models analysed using either shell or solid elements, or both.
The availability of these options on a particular site will depend on the licence
arrangements. The user should ensure that the program is capable of handling the
required modelling before proceeding further.
For versions capable of handling only shell element models, all references to solid
elements should be ignored and the following commands are not available:
DATUM, ORIGIN, RECTANGULAR-AXES, SECTION, SURFACE, STRESS -
INTEGRATION.
For versions capable of handling only solid element models, all references to shell
elements should be ignored and the following commands are not available:
CLEAR-SELECT, PANEL, SELECT.
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Concrete-Check – User Manual Program Description
2. PROGRAM DESCRIPTION
2.1 OVERVIEW OF THE CONCRETE SUITE
The CONCRETE suite comprises three separate but integrated programs:
− CONCRETE-ENVELOPE: this produces envelopes (maximum/minimum ranges)
of load for selected locations or regions of the structure across selected load cases.
These envelopes are used for strength and serviceability checks in CONCRETE-
CHECK;
− CONCRETE-CHECK: this performs code-checks on selected locations or regions
of the structure. Strength, serviceability and fatigue checks may be performed
selectively using loads provided by the user, obtained directly from the FE analysis,
or transferred by CONCRETE-ENVELOPE. Additional cylinder implosion and
panel buckling calculations may be provided using direct input data;
− CONCRETE-PLOT: this program will extract results of the enveloping or code
checking process that have been stored by CONCRETE-ENVELOPE or
CONCRETE-CHECK. These results will then be formatted into selected plot file
format for proprietary graphics presentation packages.
Both of the above programs will interface with a finite element analysis via the binary
interface files produced by the FE system in use. The suite of programs may be used in three
modes of operation:
− CONCRETE-CHECK may be used as a stand-alone program accepting all input data
and loading from the user. Strength, serviceability, fatigue, implosion and panel
stability checks may be performed. There is no interface with any FE system when
operating in this mode. No plotting of results via CONCRETE-PLOT is available in
this mode;
− CONCRETE-CHECK may be used as a direct post-processor to the FE system,
obtaining loads directly from the binary interface file produced by the analysis.
When operating in this mode, the user provides geometry data and selects individual
locations and load combinations for post-processing to strength, serviceability and
fatigue limit states;
− CONCRETE-CHECK may interface with the FE system via the CONCRETE-
ENVELOPE program. CONCRETE-ENVELOPE should be run to scan areas of the
structure and identify locations and loads for subsequent checking. CONCRETE-
CHECK may then access the loading stored and perform strength and serviceability
checks as required. This facility is particularly useful for rapidly producing checks
on large areas of a structure.
Figure 2.1-1 shows the latter two modes diagrammatically. This figure illustrates the course
of post-processing for an FE analysis. The use of CONCRETE-CHECK in a stand-alone
mode and for implosion and panel stability checks is not illustrated, neither is the interface
to CONCRETE - PLOT.
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Concrete-Check – User Manual Program Description
Details of the CONCRETE-ENVELOPE and CONCRETE-PLOT programs may be found
in separate user manuals. The remainder of this manual describes the CONCRETE-CHECK
program only.
2.2 METHODS OF SLAB ANALYSIS
CONCRETE-CHECK has two methods for solving a reinforced/prestressed concrete slab
under general loading to obtain concrete strains and reinforcement and prestress stresses.
These methods are as follows:
− a simple strip theory approach using the simplified stress block approach in
BS8110: Part 1: Figure 3.3 for ULS or elastic theory for SLS and FLS;
− a general solution using a layered approach that is an extension of those proposed
by Morley and Gupta.
The theory for both approaches is found in the Theory Manual for the CONCRETE suite.
The following description merely serves to indicate when to select a particular method.
The strip theory approach is capable only of checking a concrete section under the action of
loads perpendicular to the section. Simplifying assumptions are made to work out the
effective area of reinforcement and prestress that is not normal to the section. The method
should therefore only generally be used to check regions of the structure under
unidirectional load or where loads from the two principal directions are uncoupled by shear
loads, torsion or skew reinforcement.
The layered method is a general solution for a concrete slab and is capable of handling
loading in either principal direction, torsion and in plane shear. The approach allows the
assessment of skew reinforcement stresses and evaluates concrete crack directions and
principal stress orientation. The method further allows a variety of concrete and steel stress-
strain relationships and is applicable in regions with general state of stress.
From the above, it is evident that the layered method is technically preferable in all
instances, treats uncoupled stresses at least as accurately as the strip method and has far
greater applicability. However, it is generally more time consuming than the strip theory
approach and it is possible that the iteration procedure may be unstable under some
combinations of load. In instances where a large number of checks are to be performed, or
where convergence is difficult to obtain, the simple strip theory approach may be
considered, at least as a first approach.
Either method may be used for strength, serviceability and fatigue checks. The methods
require some control over the iterations performed. In general, the user should use the
default values of these control parameters unless the program indicates that they are
insufficient, when the analysis should be rerun with revised values.
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Concrete-Check – User Manual Program Description
Shear checks may be performed when using either the strip theory and layered approaches
under strength level (ultimate) loading. The strip theory approach considers only that
component of shear perpendicular to its section, whilst the layered method scans for the
worst direction of shear, Once again, the strip theory method is quicker and perfectly
acceptable for unidirectional loading, but the layered method offers a more general
solution,
2.3 ULTIMATE STRENGTH CHECKS
CONCRETE-CHECK can perform ultimate strength checks on a given
reinforced/prestressed concrete section under ultimate load.
Ultimate loads are defined as envelopes for each component of load on the concrete section
or block being checked. Envelopes are the maximum to minimum ranges that a particular
load component can take. These envelopes may be input by hand, or may be obtained from
backing files created by CONCRETE-ENVELOPE.
CONCRETE-CHECK can also take load values directly from the FE analysis. In this case,
'envelopes' are still created, but the maximum and minimum values will be identical.
CONCRETE-CHECK will check the section using selected critical combinations of
maximum and minimum load component. The only exception to this will be when the
maximum and minimum values are the same (or nearly so). In this case, the maximum
absolute value only will be used in the analysis, thus reducing the number of combinations
of maximum and minimum values to check.
For each combination of load, either the strip theory or layered approach may be used to
solve the section, The approach to this solution is slightly different in each case:
− for the strip theory approach, the ultimate moment of resistance of the section under
given normal load is calculated using an iterative approach, and this is compared with
the applied moment to identify failure;
− for the layered method, the concrete block is strained incrementally until the
resistance of the section matches the applied loads, or until the block fails, whichever
is sooner.
In either case, if the section proves to be acceptable as a result of the checks, then the results
are output and the next load combination considered. However, if the section fails, then the
program may proceed to redesign certain layers of steel in the section that had been
prespecified by the user. This redesign will continue for a finite number of redesign loops or
until the section passes. The newly redesigned section is then used for the next and
succeeding load combinations.
CONCRETE-CHECK will also assess the resistance of the slab to out-of-plane shear loads.
Slightly different checks are performed for the strip theory and layered methods as
described in Section 2.2. However, either method will assess the minimum
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Concrete-Check – User Manual Program Description
requirement for links and compare this with a user specified value. These shear checks use
empirical formulae based on selected codes. Currently available rules are BS8110,
BS5400, DnV and NS3473.
2.4 SERVICEABILITY CHECKS
CONCRETE-CHECK allows the user to perform serviceability limit state checks on the
concrete slab to determine if the structure is adequate in service. Three checks are
performed:
− a limit state of cracking will be checked by evaluating crack widths and
comparing these with acceptable levels provided in the data;
− a limit state of permanent damage will be assessed by evaluating the steel and
concrete stresses at working load and ensuring that these do not exceed allowable
limits;
− a limit state of watertightness will be checked to DnV criteria.
Both the BS8110 strip theory and layered approaches may be used to obtain the strains
necessary to evaluate crack widths and stresses. The user may select either approach, taking
guidance from the comments in Section 2.2.
The limit state of serviceability checks will be performed for envelopes of load in an
identical fashion to the ultimate strength checks (see Section 2.3). However, the number of
load combinations may be reduced as crack width evaluation need only be performed for
combinations of envelope values showing maximum tensile stress in each fibre.
Crack width calculations may be based on BS8110, B55400, CEB/FIP MC78 or NS3473
formulae.
2.5 FATIGUE CHECKS
CONCRETE-CHECK will perform fatigue checks on concrete slab locations specified by
the user. Checks will be performed on the concrete extreme fibres and on each
reinforcement layer in the slab.
Load combinations for fatigue analysis may be specified by user input or may be obtained
directly from the FE analysis. Load combinations may be provided in one of two forms:
− for each load cycle such as wave (height, period, direction), a time history of load
combinations through the cycle may be provided as individual load combinations.
As few as two such combinations are required (at maximum and minimum load),
but more may be specified to be sure of obtaining a realistic range of stress for
each location to be checked;
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− for each load cycle, load data can be represented in complex form as real and
imaginary load combinations. A static combination must be associated with each
cycle as concrete fatigue is affected by absolute stresses, not just stress range. The
program will scan through the complex representation of the loading to determine
the maximum/minimum stresses.
Given the above loading, a detailed cumulative fatigue assessment will be carried out on
locations selected by the user. The fatigue assessment will use a deterministic approach to
provide the fatigue life for the slab location being checked based on yearly occurrences
given in the data.
Concrete and steel stresses for each load condition (wave height, period, direction, phase)
may again be evaluated using either the BS8110 strip theory or layered approaches, at the
discretion of the user, Again, the strip theory method is quicker, but should only be used in
areas where the shear and torsion loads are not critical and where in-plane shear and torsion
are small throughout the wave cycle.
2.6 IMPLOSION AND PANEL STABILITY CHECKS
CONCRETE-CHECK also has the capability to perform implosion and panel stability
calculations. The implosion checks are intended for cylinders or curved panels, while the
panel stability checks are restricted to flat panels.
Neither of the above checks require or receive geometric or stress data from an FE analysis.
In both cases, the cylinder or panel geometry and the in-plane and pressure loading are
obtained from hand input data only.
In both cases, the program evaluates the critical buckling capability of the cylinder or panel
and compares this with applied loads to yield a factor of safety against buckling, The
methods used are described in the Theory Manual.
If the cylinder implosion factor of safety is greater than one, the program can proceed to
calculate imperfection bending moments in the cylinder. One single imperfection bending
moment is produced for the cylinder (which may be positive or negative). This moment may
then be fed back into a limit state analysis in conjunction with the prebuckling loads using
direct input.
2.7 HANDLING OF PRESTRESS LOADS
Prestressing may be modelled in three ways in CONCRETE-CHECK:
− option (i) is for prestress tendons to be represented within the slab and be allocated a
prestress force;
− option (ii) is for prestress forces to be included as load cases from the FE analysis,
either directly or via CONCRETE-ENVELOPE;
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− option (iii) is for a combination of the above to be provided by explicitly representing
tendons and providing a prestress load case.
In the following discussion, it is useful to make two definitions:
− PRIMARY PRESTRESS is prestress on a section caused directly by the prestress
tendons within the section. Axial compression and bending in the direction of the
tendon are primary effects. Primary prestress is affected by other loads on the section
due to the requirement of strain compatibility between the tendons and the concrete;
− SECONDARY PRESTRESS is loading on a section due to prestress on other parts of
the structure, or in other directions. As far as a given section is concerned, secondary
prestress can effectively be considered as a constant external load and is considered
unaffected by strains within the section itself.
Option (i), above, represents the primary effects of prestress alone and may safely be used
where the secondary effects of prestress are small. The method provides full strain
compatibility between prestress tendons and the concrete.
Option (ii), provides the effects of secondary prestress only and may be used where the
effects of strain compatibility are not important, or where no primary prestress is provided.
Option (iii), allows for both the primary and secondary effects of prestress as follows:
− primary prestress loads are evaluated from the stress in all tendons in the section;
− total or secondary prestress loads are obtained from prestress load cases;
− if total prestress has been provided, primary prestress is subtracted from total to yield
secondary prestress loads. If secondary prestress has been provided, primary prestress is
added to secondary to yield total prestress loads;
− secondary prestress loads are factored and added to other external loads to form part of
the constant loading on the section;
− the section is then analysed under the action of primary prestress (which is strain
compatible) and external loads (which are not).
The choice of which option to use is up to the designer/analyst. If prestress tendons are
modelled, but no prestress load cases are provided, then option (i) is assumed. Option (ii) is
simulated by providing only prestress load cases. Any combination of modelled prestress and
prestress loading is handled as for option (iii), above.
It is important that prestress is provided as separate load cases and not built in to other
applied loading. The reason for this is that prestress loading will in general
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Concrete-Check – User Manual Program Description
have a different safety factor for different types of check (ULS, shear, SLS). These prestress
factors may be specified in CONCRETE-CHECK, so that unfactored stresses should be
obtained from the FE analysis.
2.8 DEFORMATION LOADS
The analysis of deformational (thermal, settlement, etc) loadcases for concrete structures by
linear elastic analysis methods can lead to gross over estimates of the loads that will be
developed. This occurs because the cracking and softening of concrete under load and
possible yield of steel will act to limit the load at a given strain (i.e deformation).
CONCRETE-CHECK allows for a separate deformation loading to be defined. Internal to the
program the deformation loads are converted to equivalent strains before inclusion in the
analysis of the concrete section. The adoption of deformation strains enables the layered
method to allow for the effects of cracking, yielding, etc across the section. No such
allowance is possible for the strip method which simply adds the deformational loads to other
applied loads (see discussion in the Theory Manual).
The load-deformation relationship for the section is non-linear, therefore the sequence of
loading is important, CONCRETE-CHECK allows for a simple loading sequence by
permitting the definition of non-deformational loadcases (ENVELOPE and POST-
DEFORMATION-LOADS) either side of the application of the deformational
(DEFORMATION-LOADS) case. For example, the dead load on a structure might be applied
as an ENVELOPE load, a thermal case as a DEFORMATION-LOAD and environmental
load as a POST-DEFORMATIONLOAD. In the above example CONCRETE-CHECK
would perform the following sequence of calculations:
− pre-deformation strains resulting from the dead load are calculated;
− equivalent thermal strains are added to the pre-deformational strains enabling
dead+thermal load to be derived;
− finally the environmental load is added to the dead+thermal load so that the final section
strains and stress distribution in all items in the section can be calculated.
To permit the conversion of deformation loads to strains, the modulus of elasticity and
Poissons ratio used in the linear stress analysis must be specified using the DEFORMATION-
PROPERTIES command.
As for ENVELOPE loads, DEFORMATION-LOADS and POST-DEFORMATIONLOADS
can both be specified from three distinct sources:
− direct from a command in the input file;
− by reference to a load envelope created by CONCRETE-ENVELOPE;
− by reference to a load case and location in an FE analysis model.
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2.9 PROGRAM LIMITATIONS
The following limitations are set within CONCRETE-CHECK:
- maximum rebar layers at a section 16
- maximum tendon layers at a section 10
- maximum number of rebar types 9999
- maximum number of tendon types 9999
- maximum number of rebar materials 10
- maximum number of tendon materials 10
- maximum number of concrete layers 50
- maximum number of fatigue cycles 100
- maximum number of steps per cycle 10
- maximum number of fatigue combinations 250
- maximum number of words on instruction line 30
- maximum number of elements in group 1000
- maximum number of nodes in a class 1500
- maximum common elements at a node 16
- maximum fields in a key 10
- maximum key symbols 20
The following limits apply to solid element models:
- maximum number of locations on section 100
- maximum number of stress points at location 100
- maximum number of intersected elements 50
- maximum number of nodes on these elements 100
The following limits apply to plate element models:
- maximum number of boundary (edge) nodes 200
- maximum number of corner nodes 20
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Concrete-Check – User Manual Program Description
FIGURE 2.1-1: USE OF CONCRETE PROGRAMS
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Concrete-Check – User Manual Running the Program
3. RUNNING THE PROGRAM
3.1 INTRODUCTION
CONCRETE-CHECK operates by taking data from a text data file and writing results to an
output file and a summary file. Optionally, plot results may be written to several plot files
and data input may be redirected to other input files. Each of these facilities will be
described in the following sections.
3.2 COMMAND LINE
All programs in the CONCRETE suite contain a command line interpreter so that input,
output and other file names can be entered after the program name as a single command on
all machine types (e.g. program name file1 file2 ...). File names on the command line must
be specified in the following order:
1) data file name and location:
2) output file name and location;
3) summary file name and location;
4) plot file stem.
The data file name must always be specified, although it need not be given an extension if it
is ‘.dat’ (or ‘.DAT’ on machines that are not case specific or require upper case).
Other file names are optional. If not given, the last specified file name on the command line
is used as a basis with a new extension defined by the program. The following default
extensions are given to file types:
− output files are ‘.out’ or ‘.OUT’;
− summary files are ‘.sum’ or ‘.SUM’;
− plot files should never be given an extension, as the stem is suffixed with ‘nnnn.plt’
or ‘nnnn.PLT’, where nnnn is a sequential number starting at 0001. The default plot
stem is ‘plot’.
Examples of the use of the command line will follow for specific platforms/operating
systems.
Existing output and plot files of the names specified are always deleted by the program at the
start of execution. A suitable message is given, but the user should ensure that required
results are not lost in this way.
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Concrete-Check – User Manual Running the Program
3.3 CHANGED INPUT STREAMS
All CONCRETE programs feature a CHANGE-INPUT-STREAM command that allows
data input to be redirected to another input file on another unit or stream. This is achieved
by specifying in the data the unit number and file name to be used for future data input.
Input may be redirected as required to other files or returned to an original file as required.
This is a useful facility that allows repetitive data to be located in separate files and accessed
when needed from several different runs.
Refer to the CHANGE-INPUT-STREAM command in Section 5.0 for more details.
3.4 INPUT AND OUTPUT CHANNELS
Several units, streams or channels are used by the program for input/output. These are listed
here as they should not be used for CHANGE-INPUT-STREAM input file redirection:
− Unit 5 data input
− Unit 6 main output
− Unit 52 summary files
− Unit 53 plot file
− Units 1 and 99 screen output
When an FE package is used to provide stress and geometry data, it may use additional
units. Refer to the appropriate appendix for details.
3.5 BATCH FILES
A convenient method of running the program is to create a batch file that includes the
necessary instructions for program execution, and perhaps echoes back information on the
program version and data files that are in use.
A sample batch file is given below. This example includes echoing of data to the screen,
checking to see if a plot file is specified and running the program as required. Output and
summary file extensions are set to be .LIS and .SUM.
No directory path to the executable is specified; the batch file assumes that the executable is
located in the default installation directory C:\Program Files\ANSYS
Inc\vvvv\asas\bin\win32 (where ‘vvvv’ is the version number), or that the directory is
included in the path. See the ANSYS Installation Guide for more details.
@ECHO OFF
ECHO.
ECHO Running CONCRETE-CHECK
ECHO.
ECHO Data file = %1.DAT
ECHO Results file = %1.LIS
ECHO Summary file = %1.SUM
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IF “%2A”==“A” GOTO NOPLOT
ECHO Plot file stem = %2
ECHO.
CCAS %1 %l LIS %1 %2
GOTO END
:NOPLOT
ECHO.
CCAS %1 %1.LIS
:END
ECHO.
ECHO Problem Complete
ECHO.
ECHO ON
If this file were called CHECK.BAT and were located on the path, then a run using
EXAMPLE.DAT as input would be started as follows:
> CHECK EXAMPLE
If plots were required (called PLOT0001.PLT, etc), then the command format would be
simply changed to:
> CHECK EXAMPLE PLOT
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4. DATA PREPARATION
4.1 INTRODUCTION
Input data for the CONCRETE-CHECK program is used to control the execution of the
program, organise file handling, provide data values, select results, etc.
Input data is initially read from the data file assigned via the command line. This input may
subsequently be redirected to other physical files using the CHANGE-INPUT-STREAM
command (see Section 3.2 and Section 5.0).
The input data file, and any other redirected input files, contain consecutive instructions,
each occupying one or more physical lines in the file. Each instruction consists of a
keyword and a variable number of parameters. Keywords are described, in alphabetical
order, in Section 5.
Instructions are executed consecutively, but the majority of commands simply set up
internal data and perform no checking functions. Only when a DO-CHECKS instruction is
encountered are code checks performed, and then only if code checking has been selected
to one or more limit states.
Each use of an instruction overwrites settings created by default or by previous uses of that
instruction. When a DO-CHECKS command is reached, the latest settings are used.
Exceptions to this, such as SELECT, FATIGUE-CYCLES, TOP-STEEL, BOTTOM-
STEEL and DEBUG are so noted in Section 5.0.
4.2 UNITS
Several commands in CONCRETE-CHECK require values to be input in specific units.
The program expects input data units which have been chosen to follow standard
engineering practice:
- slab dimensions (thickness, cover, diameters, spacing) in millimetres (mm); panel and
cylinder dimensions in metres (m);
- section data in FE analysis units;
- stresses and pressures in MNm-2 (or Nmm-2);
- forces per unit width in MN per m (MNm-1);
- moments per unit width in MNm per m. (MN);
- times in seconds (s);
- angles in degrees (deg).
CONCRETE-CHECK works internally in units of Newtons and mm. When obtaining
results from an FE system (either directly or via CONCRETE-ENVELOPE), the data will
have the units of the FE analysis. The UNITS card may be used to change the analysis units
to the CONCRETE-CHECK system.
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4.3 SIGN CONVENTION AND SLAB AXES
The entire CONCRETE suite, including CONCRETE-CHECK, uses a compression-
negative, tension-positive sign convention for all stresses. This is generally the same as the
FE system in use, but exceptions are noted in the appropriate appendix and are converted
automatically.
CONCRETE-CHECK will also convert shear, bending and torsional loads into a consistent
sign convention, if so required. The CONCRETE sign convention is illustrated in Figure
4.3-1 and described below:
− direct stresses are tension-positive;
− positive shear causes elongation in both the (X>0, Y>0) quadrant and the (X<0, Y<0)
quadrant;
− bending moments, including torsion, are positive if they cause positive direct stresses
in the BOTTOM fibre. This means that sagging moments are positive and hogging
moments are negative.
The slab axis system is also illustrated in Figure 4.3-1. The X" and Y" axes are the stress
reference directions in the plane of the slab. The Z" axis is the slab normal. The X", Y" and
Z" axes form a right handed system. The orientation of these axes within a shell element
structure generally follows the FE system axes at each node. Exceptions are noted in the FE
system appendix. Stress orientations in a solid element model are defined by the surface 1
location definition in accordance with Section 4.10.
Note that the NX and MX loads cause stresses in the X" direction, NY and MY cause Y"
stresses and NXY and MXY cause shear. The MX and MY designation for moments should
not be confused with the more conventional MXX and MYY designation for beams, which
are defined as moments ABOUT each axis, not as moments which CAUSE stress in each
axis.
4.4 FORMAT OF INSTRUCTIONS
Each instruction consists of a keyword, generally followed by additional data (which may
be numeric or text). Each instruction starts on a new line and the items of data are separated
from the instruction keyword and from each other by blank spaces.
Each instruction line must be 80 characters or less in length, including embedded blank
characters. For some instructions which require substantial amounts of data, continuation
lines may be used as described below.
Note that upper case letters are used throughout for keywords, both for instructions and in
the data.
4.5 ABBREVIATION OF INSTRUCTIONS
Most of the instruction keywords are quite long, generally comprising several words
separated by dashes, such as DATA-CHECK-ONLY. Although it is recommended that the
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instruction be entered in full (as this renders most data files reasonably legible without extra
comments), the keyword may be abbreviated subject to certain conditions:
− the first letter, all dashes and the letters immediately followed dashes must be included;
− the remaining letters must be in the correct order;
− the resulting abbreviation must not be ambiguous, in that two different instructions
could both be abbreviated in the same way (for example, SE is not an acceptable
abbreviation for SELECT because it is also a possible abbreviation of SURFACE. This
restriction of non-ambiguity extends to all instructions in CONCRETE-ENVELOPE
and CONCRETE-CHECK regardless of which programs are actually installed.
Keywords in the data following an instruction keyword may also be abbreviated subject to
the same rules, provided that the abbreviation is not ambiguous with respect to any other
keyword that could be used with the particular instruction.
If an ambiguous instruction is supplied in the input data, CONCRETE-CHECK will print a
warning and arbitrarily choose which instruction to execute.
4.6 CONTINUATION LINES
There is, as described above, a limit of 80 characters for any line of data, The following
instructions require more data than can be easily fitted within this limit and so allow the use
of continuation lines:
COMBINATION, CONCRETE-PROPERTIES, ENVELOPE, PRESTRESS-
LOADS, STATIC-COMBINATION, SECTION
A continuation line is denoted by a plus (‘+’) character in the first column of the line.
Comment lines (see below) may be included before each continuation line. Individual data
fields may not be split over two separate lines, so, for example:
INSTRUCTION 12 +34
would be interpreted as INSTRUCTION 12 34 not as INSTRUCTION 1234. Where
continuation lines are allowed, this is clearly demonstrated in the description of the
command.
4.7 COMMENT LINES
Comment lines may be included in the input data file. These are denoted by an exclamation
mark (‘!’) in column one of the line. All text following the exclamation mark is echoed, but
otherwise ignored.
It is recommended that comment lines are used liberally to indicate, for example, the source
of the input data, assumptions that are being made, etc., as they prove invaluable when it is
necessary to rerun an old analysis.
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4.8 SUMMARY FILE COMMENTS
The comments described in the previous section have no effect beyond being listed in the
main data echo. However, comments may also be included for echoing in the summary
output file. Such comments are indicated by a hash sign (‘#’) in the first column of a data
line. These comments are copied to the summary file and to the main data echo (if
appropriate), but are otherwise ignored.
The user also has control over the headings for the summary file. An asterisk (‘*’) results in
a new page and new column headings. Any comments following the ‘*’ will also be copied
to the summary file.
These facilities give the user considerable control over the format of the summary file so
that report quality output can be produced.
4.9 RECOVERY OF ENVELOPES
When used as a post-processor to CONCRETE-ENVELOPE, CONCRETE-CHECK
recovers its envelopes from backing file. The CONCRETE suite uses a keyed filing system
for storage of envelopes on backing file. This keyed filing system is a flexible system that
allows the user full control over the storage of results and later retrieval by CONCRETE-
CHECK. However, due to the flexibility, the system requires careful explanation to fully
describe its capabilities. That explanation is provided here.
Each envelope produced by CONCRETE-ENVELOPE may be stored on backing file for
subsequent access by CONCRETE-CHECK. Panel node envelopes will be produced per
node in a set and per class over an entire set. Class envelopes are distinguished by a node
number of zero. Section location envelopes will be produced per location around the
section and for the entire section. These overall envelopes are distinguished by a location
number of zero. Global envelopes may also be stored.
Each envelope stored by the program is allocated a ‘key’ so that it can be recalled directly
by CONCRETE-CHECK. Instead of the user specifying this key directly, CONCRETE-
ENVELOPE will internally calculate the key given a user specified key definition. The
same definition should be provided in CONCRETE-CHECK to access these envelopes.
Each key is defined by a set of ‘fields’. Up to fifteen are allowed currently. Each field is
allocated a 'symbol' and a 'range' by the KEY-FIELDS and KEY-RANGES instructions,
The symbol may be a user defined symbol (see the NEW-SYMBOL and SYMBOL-
VALUE commands) which can have a user defined value, Alternatively the symbol in any
field may be one of the following:
NODE, LOCATION, GROUP, SET, CLASS, SECTION, ENVELOPE
These symbols are automatically updated by the program for a given node, set, class, etc.
when each envelope is stored.
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The range of a field must be defined by the user and must enclose all possible values that
the symbol may take. Note that the range for a NODE or LOCATION field must start at
zero as the symbols will be given the value of zero for a class envelope. Similarly, the
GROUP, SET and SECTION symbols may also be zero if global envelopes are used. For a
given key definition, the maximum key that can be produced will be the product of all of
the individual key ranges, i.e.:
. MAXKEY = (max1 – min1 + 1)*(max2 - min2 + 1)*…..*(maxn - minn + 1)
where max and min define the ranges of each of 1 to n keys.
The actual value of a given key will depend on the current values of each of the symbols
that occupy the key fields at the time that the key is evaluated (when an envelope is to be
stored). This is best demonstrated by example.
Suppose a key definition comprises three key fields as follows:
Field 1: Symbol ‘CASE’ range 1 to 4
Field 2: Symbol ‘GROUP’, range 1 to 10
Field 3: Symbol ‘NODE’, range 0 to 100
CASE is a user defined symbol, GROUP and NODE are reserved symbols. The maximum
key value is given by:
MAXKEY = (4-1+1)*(10-1+1)*(100-0+1) = 4040
Suppose the symbol values are as follows for the storage of a particular envelope:
CASE = 2, GROUP = 3, NODE = 35
The key evaluation for this data would be as follows:
KEY = (2-1)*(10-1+1)*(100-0+1)+(3-1)*(100-0+1)+(35-0)
= 1010 + 202 + 35
= 1247
It is clear that there is therefore one unique key value for each combination of the values of
the symbols as long as each value stays within the specified range.
The following should be noted:
− once a keying system is defined, it may not be changed without the risk of overwriting
all previously stored envelopes, so care should be taken to ensure that the keying
system is correctly defined at the start (particularly that the ranges are large enough for
all eventualities);
− the keying system should therefore generally be the same between different
CONCRETE-SUITE runs on the same structure;
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− the reserved symbols are of great use in setting keys for all nodes across a set, all sets,
etc, and should be included in the key definition where possible. The above example is
a very simple use of this;
− the user defined symbols allow other parameters to be used to govern keys, such as
loadcase, superelement number, etc.;
− the key system defined in CONCRETE-ENVELOPE should generally be the same as
that defined in CONCRETE-CHECK to allow the required envelopes to be recovered
by using the same key calculation;
− however, it is possible to change key structures as long as care is taken. In particular, it
is possible to use a single key field to allow a key to be defined directly via the
SYMBOL-VALUE command. Experienced users may attempt this.
4.10 SECTION DEFINITION
Load components may be recovered directly from the FE analysis either at specified nodes,
across entire panels, or using the section definition approach common to CONCRETE-
ENVELOPE. The section definition approach is described here.
Sections may currently be defined in structures modelled using solid elements only, and the
rest of this section refers only to models of this type.
A 'section' is defined by the intersection of a ‘surface’ with a given ‘subset’ of elements.
The following commands are therefore obligatory to define a section:
− SET or GROUP to define the subset of elements;
− SURFACE to define the PLANE, CYLINDER or CONE used to intersect with
the elements.
Locations may be specified on the section for calculation of stresses:
− SECTION allocates a number to the section for storage of envelopes and defines
locations along or around the section at which envelopes are required.
The following optional commands may also be used in the definition of sections:
− ORIGIN to define the origin of a surface;
− DATUM to define the datum relative to which locations for enveloping are
required.
Figure 4.10-1 illustrates the full definition of a PLANE surface and shows how the datum
command is used in this case to define the axis of the through-thickness direction and to
provide a datum relative to which locations along the section are defined (by loci, loc2,
etc). The following procedure is adopted to define these locations:
− the PLANE is defined by its normal vector and origin;
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− the SECTION is defined by the intersection of the surface and the subset of
elements;
− the datum vector is projected into the PLANE and defines the local surface Z' axis;
− the surface Y' axis is in the direction of the normal vector;
− the surface X' axis forms a right handed system with Y' and Z';
− the locations for enveloping are identified by the values given on the SECTION
command. For a PLANE, X co-ordinates in millimetres are expected;
− the location axes at each location for a PLANE are identical to the surface axes.
Similar methods are used to define the locations to be enveloped for CYLINDER and
CONE surfaces, as illustrated by Figures 4.10-2 and 4.10-3, but the through-thickness
direction is taken to be axial and radial from the origin, respectively. The following revised
procedure is used:
− the surface is defined by the centroidal axis, origin and a surface value. For a
cylinder, the value is a radius in millimetres, for a cone, an angle to the axis is
required;
− the section is defined as the intersection between the subset of elements and the
cylinder or cone;
− the datum vector and axis together define a datum plane;
− the surface Y' axis is in the axial direction;
− the surface Z' axis is also in the datum plane towards the datum vector; the
surface X' axis forms a right handed system with Y' and Z'; section locations
are measured around Y' from the Z' axis;
− for the CYLINDER, the location Z" axis is in the axial direction; for the CONE, it
is radial from the origin to the location;
− the location X" axis is measured around the section (positive sense); the
location Y" axis forms a right handed system.
A further reorientation of stresses may be achieved by use of the RECTANGULAR-AXES
command. This optionally allows loads per unit width recovered for solid element models
to be orientated to a consistent set of axes before any further processing.
This is particularly useful for sections defined by cylinder or cone section intersections
where the reinforcement pattern is rectangular. This is illustrated by Figure 4.10-4. Without
RECTANGULAR-AXES, loads at each location identified would normally be related to
different local axes. Use of the RECTANGULAR-AXES command forces these into a
consistent system. This allows a much simpler single definition for reinforcement in the
CONCRETE-CHECK analysis,
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MEMBRANE LOADS
Ny
My
Mx
SLAB AXIS SYSTEM
FIGURE 4.3-1: SIGN CONVENTION FOR CONCRETE SUITE
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FIGURE 4.10-1: DEFINITION OF PLANE
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FIGURE 4.10-2: DEFINITION OF CYLINDER SECTION
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SURFACE AXES GLOBAL AXES
LOCATION AXES
FIGURE 4.10-3: DEFINITION OF CONE SECTION
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WITHOUT RECTANGULAR-AXES
WITH RECTANGULAR-AXES
FIGURE 4.10-4: USE OF RECTANGULAR-AXES
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5. COMMAND FORMATS
The following pages describe the commands available within the input data file for
CONCRETE-CHECK. Commands are presented on individual pages, in alphabetical order.
The following convention is used to describe the instructions in the syntax:
− keywords are presented in capital letters;
− other text/numerical data is represented by lower case words; optional
data is enclosed in brackets, ‘( )’;
− choices of keywords or data are separated by slashes, ‘/’;
− lists of data are indicated thus ‘----‘. The logic of the repetition list is often self-
explanatory but may be augmented in the command description.
A summary of the commands available is presented in Appendix 'A'. The summary is useful
to remind experienced users of the instruction formats, but includes no description of the
data.
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Command : ADDITIONAL-STIFFNESS
Syntax : ADDITIONAL-STIFFNESS (cstiff(rstiff(tstiff)))
Applicable to : All limit state checks using layered method
Examples : ADDITIONAL-STIFFNESS 10000
ADDITIONAL-STIFFNESS
ADDITIONAL-STIFFNESS 8000 50000 100000
Description:
The ADDITIONAL-STIFFNESS command allows the definition of further linear elastic
moduli for concrete, reinforcement and prestress tendons. If any stiffness is not specified, it is
assumed to be zero. Zero is also the default at program start up. Units of stiffness are Nmm-2.
When additional stiffnesses are in use, the stress-strain curves for concrete, rebars or tendons
are modified to give the greater numerical stress from either the original curve or from the
above linear relationships. If the above stiffnesses are set relatively low, this has the effect of
not changing the stress strain curve through working strains, but providing residual stiffness
at high strain (a form of strain hardening). The main use of this facility is to prevent
divergence in the layered method by providing stiffness for both concrete and steel after
crushing/yielding. Resultant stresses will be artifically high, but this will be evident from the
utilisations and will give an indication of why the sections if failing.
the following rules apply to additional stiffness:
− the concrete stiffness applies only to compression, never to tensile strains;
− reinforcement compressive stresses are unaltered (at zero) if compression steel is
ineffective;
− tendon compressive stresses are unaltered if the compressive modulus and strength
have not been specified;
− the specified stiffnesses will be reduced by the appropriate material partial safety factor
prior to use by a particular limit state. This allows the additional stiffness to become
effective at a predetermined strain, irrespective of limit state;
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Command : ANALYSE-NODE-CLASSES
Syntax : ANALYSE-NODE-CLASSES classl(class2{class3{class4)))
Applicable to : All limit state checks
Examples : ANALYSE-NODE-CLASSES 1 2 3 4 (default)
ANALYSE-NODE-CLASSES 3 2
Description:
The ANALYSE-NODE-CLASSES instruction is used to indicate which classes of location
are to be analysed. The concept of node class is described below.
The instruction is followed by a list of class numbers, each between 1 and 4 inclusive,
indicating the classes to be analysed. Classes not listed will not be checked. These
instructions are not cumulative and apply to succeeding DO-CHECKS instructions until the
next ANALYSE-NODE-CLASSES instruction is encountered.
This command is most useful when code checking global envelopes {set or group of zero)
as it is the only way to suppress checks on specific classes of set envelope. It may also be
used in conjunction with PANEL SAMPLE and PANEL SWEEP to suppress checks on
unwanted classes of node. In all other events, it is sensible to activate all classes of node or
location. This latter condition is, in fact, the default.
The current classes allowed in the CONCRETE suite are as follows:
Class 1: Panel Corner Nodes;
Class 2: Panel Edge Nodes;
Class 3: Panel Interior Nodes;
Class 4: Section Locations.
See also the SELECT, CLEAR-SELECT, SET, GROUP, PANEL and SECTION
commands for further details.
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Command : BEGIN-PLOT
Syntax : BEGIN-PLOT
Applicable to : All limit state checks
Examples : BEGIN-PLOT
Description :
The BEGIN-PLOT command is used to start the writing of CONCRETE-CHECK results to
plot file for subsequent plotting by the PLOTIT utility program. It should not be confused
with the plotting capability via CONCRETE-PLOT, which uses results stored by the
WRITE command.
The following results will be written to the plot files (if available) when DO-CHECKS
commands are encountered:
ULS - Total Main Steel Areas ULS - Link Steel Areas
SLS - Maximum Crack Width SLS - Maximum Rebar Stress
FLS - Concrete Fatigue Life
FLS - Minimum Rebar Fatigue Life
FLS - Minimum Tendon Fatigue Life
The writing of plot results is ended when a FINISH-PLOT command is encountered but
may be restarted as required later in the data check by another BEGIN-PLOT command.
Note that this command is only really useful when used in conjunction with the SECTION
command used to define positions at which checks are to be performed. The appropriate
results from above may then be plotted against this position. When running in stand-alone
mode, the following example shows how sensible plots can be obtained;
SET 1
.
.
BEGIN-PLOT
ENVELOPE envelope values
SECTION 1 LIST 0.0.
DO-CHECKS
ENVELOPE envelope values
SECTION 1 LIST 1.0
DO-CHECKS
.
.
FINISH-PLOT
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Command : BOTTOM-STEEL
Syntax : BOTTOM-STEEL REBARS/TENDONS type cover angle (resize)
Applicable to : All checks
Examples : BOTTOM-STEEL TENDONS 3 100.0 0.0
BOTTOM-STEEL REBARS 6 30.0 90.0 0.05
Description :
The BOTTOM-STEEL command allows the definition of reinforcement layers and tendon
layers relative to the bottom face of the concrete slab being checked. The command is
similar to TOP-STEEL, which allows definition relative to the top face.
The bottom face of the slab is defined as the face with the lower slab normal (Z") co-
ordinate. Refer to Section 4.3 for details of the slab axis system.
Both reinforcement steel (REBARS) and prestress tendons (TENDONS) can be defined
with this command. The following additional data is required:
type - an integer referencing a REINFORCEMENT-BARS or PRESTRESS-
TENDONS card with details of the diameter, spacing, material, etc. for
the steel. The appropriate type integer must have been set up when a DO-
CHECKS instruction is encountered;
cover - the steel cover in millimetres. For rebars, this is the cover from the
bottom face to the closest point of the steel bars. For tendons, this is the
distance from the bottom face to the tendon centre line;
angle - the orientation in degrees of the steel in the plane of the slab, relative to
the slab X" axis. Refer to Section 4.3 for details of the slab axes;
resize - for ultimate limit state checks, the resize rate per resize step. This item is
only valid for REBARS, and defaults to zero if not given. During
ultimate limit state checks, CONCRETE-CHECK will automatically
resize any rebar layers with a nonzero 'resize' rate. Refer to the
REDESIGN command for more information.
Rebars and tendons may be created by successive BOTTOM-STEEL and TOP-STEEL
cards. Up to siten layers of rebars and ten layers of tendons are allowed. These layers may
be defined at the same or different depths, entirely at the discretion of the user. When a
reinforcement/ prestress arrangement must be changed, the RESET command should be
used to cancel all previous definitions.
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There is no restriction that steel should be closer to the bottom face for the BOTTOM-
STEEL command to be used. All steel may be created by either the TOP-STEEL or
BOTTOM-STEEL commands. The only restriction is that the final steel lies within the
section.
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Command : CHANGE-INPUT-STREAM
Syntax : CHANGE-INPUT-STREAM (stream (file))
Applicable to : All checks
Example : CHANGE-INPUT-STREAM 55
CHANCE-INPUT-STREAM 60 basic.dat
Description :
When a CHANGE-INPUT-STREAM command is issued, input of data immediately
switches to the stream number and file specified on some computers, this stream number
may be assigned to a file name in the CONCRETE-CHECK run control file (see Section
3.0). Alternatively, the filename may be specified as an argument to the instruction.
Input starts by default on stream 5. When a CHANGE-INPUT-STREAM command is
encountered, input switches to the new file associated with the new stream. Input may be
returned to the original file with a further CHANGE-INPUT-STREAM command with no
argument given (or with a stream number of 5). Processing will recommence at the line after
the original CHANGE-INPUT-STREAM instruction.
The above procedure allows input from two or more files. At least one of these files may be
a 'reference file' common to a number of different runs of CONCRETE-CHECK. The data
files for each of these runs will contain a CHANGE-INPUTSTREAM command to switch
input to the reference file, which will end with a CHANGE-INPUT-STREAM command
(with no argument) to return control to the original input file. Stream 5 is always the initial
input stream.
Some FE systems place restrictions on the stream numbers that are available to the user.
When using a version of CONCRETE-CHECK that is interfaced in this way, refer to the
appropriate appendix. Streams 6, 51, 52 and 53 are always reserved by CONCRETE-
CHECK.
The file parameter may be used to directly specify an eighty-character filename, rather than
by external assignment. For some operating systems, this is the only way of using the
instruction since external assignments are not possible (see Section 3.0 for further details).
In any case, the filename (which may include a directory path) should follow the syntax
required by the system in use.
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Concrete-Check – User Manual Command Formats
Command : CLASS
Syntax : CLASS (class)
Applicable to : BS5400 shear checks
Examples : CLASS
CLASS 2
Description :
This command allows the specification of a class of prestress structure used to define the
type of shear capacity calculation to be performed to BS5400 : Part 4 : 6.3.4.3.
The 'class' parameter may be set to 1, 2 or 3, If not given, or outside this range, a value of 3
will be used. The default at program start up will be 3.
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Concrete-Check – User Manual Command Formats
Command : CLEAR-SELECT
Syntax : CLEAR-SELECT class nodel (node2 ----)
Applicable to : All
Examples : CLEAR-SELECT 1 0 11 12 13 14
Description
This command allows the selection of nodes on a panel and therefore applies only to
concrete substructures modelled using thick and thin shell elements, It may also be used to
identify output when used in the stand-alone mode.
The CLEAR-SELECT command operates in a similar way to the SELECT command,
except that all previous selections of nodes and classes over a panel are cleared before the
new selection is added. The command should be used when a new group has been selected.
The action will be to clear the selection of nodes for the previous group, and start selection
for the new group. The following example data file illustrates this:
CLEAR-SELECT 1 1 2 3 SELECT 2
10 11 12
DO-CHECKS
(Nodes 1,2,3,10,11,12 checked)
CLEAR-SELECT 1 101 102 103 104
SELECT 2 110 111
DO-CHECKS
(Nodes 101,102,103,104,110,111 checked)
Note that all previous selections of nodes for all classes are cleared by this command, not
just the selection for the given class.
Node selection is cancelled by the PANEL and SECTION commands, which allow
alternative methods of selection.
A selected node number of zero signifies that a class envelope is to be recovered but is only
appropriate when CONCRETE-CHECK interfaces with CONCRETE-ENVELOPE.
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Concrete-Check – User Manual Command Formats
Command : CODE-CHECK
Syntax : CODE-CHECK (ON/OFF)
Applicable to : All checks
Examples : CODE-CHECK
CODE-CHECK OFF
Description :
The CODE-CHECK command allows code checking to be enabled or disabled for
succeeding DO-CHECKS instructions throughout the data file.
CODE-CHECK ON, or CODE-CHECK with no arguments, enables code checking, the
default condition at program start up. CODE-CHECK OFF disables this checking and is
synonymous with DATA-CHECK-ONLY.
With code checking switched off, the program will only perform data checks when a DO-
CHECKS instruction is reached, and will then proceed to input further data.
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Concrete-Check – User Manual Command Formats
Command : COMBINATION
Syntax : COMBINATION number DIRECT nx ny nxy nxz nyz
COMBINATION number ANALYSIS data --COMBINATION
number NONE
Applicable to : Fatigue Checks
Examples : COMBINATION 3 NONE
COMBINATION 21 DIRECT 1.361 -2.293 6.611 -5.282
+ 2.163 4.218 -5.963 3.218
COMBINATION 16 ANALYSIS 12
Description :
The COMBINATION command specifies the source of load combination data for a fatigue
analysis and optionally allocates values for user-defined direct input combinations.
The combination 'number' given is the reference by which this loading is known in the
FATIGUE-CYCLE instruction. Existing combinations may be overwritten by successive
uses of this command with the same 'number'.
DIRECT specifies that combination data is to be provided by direct input on this command.
These user-defined combinations may then be available for subsequent FATIGUE-CYCLE
instructions. Continuation lines may be used to specify the data. Direct loads (NX, NY, NXY,
NXZ, NYZ) are input in MN per metre width, while moments (MX, MY, MXY) are input in
MNm per metre.
ANALYSIS may be used to specify that load combination data is to be taken from FE
analysis backing files. Extra data is required on each line, but this is dependent on the FE
system in use and is described in the appropriate appendix.
NONE may be used to signify a null (zero) load combination. Up to two hundred and fifty
unique combinations may be defined in the data.
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Concrete-Check – User Manual Command Formats
Command : COMPRESSION-STEEL
Syntax : COMPRESSION-STEEL EFFECTIVE/INEFFECTIVE
Applicable to : All limit state checks
Examples : COMPRESSION-STEEL EFFECTIVE
COMPRESSION-STEEL INEFFECTIVE
Description :
The COMPRESSION-STEEL command allows control over the effectiveness of
reinforcement bars subject to compression loading. Such bars may be EFFECTIVE (using
the REBAR-PROPERTIES compression curve) or INEFFECTIVE (compressive strain
causes no stress). The command should be used to prevent compressive stress in rebars
considered to be inadequately tied in.
The command does not affect prestress tendons, which normally do not allow compression
anyway, but which may simulate compression using options in the TENDON-PROPERTIES
command.
The default at program start-up is EFFECTIVE.
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Concrete-Check – User Manual Command Formats
Command : CONCRETE-DENSITY
Syntax : CONCRETE-DENSITY density
Applicable to : All limit state checks.
Examples : CONCRETE-DENSITY 2150
Description:
The CONCRETE-DENSITY command is used to specify the value for concrete density to
be used in determining concrete strength. A single parameter is required which defines the
density of plain (unreinforced) concrete in kg/m3. The default, if this command is not given,
is 2400 kg/m3.
At present, concrete density is used only for the calculation of the cracking strength of
concrete in accordance with CSA S474-94, Clause 6.4.2. This is further described under the
CONCRETE-PROPERTIES instruction. No other properties are currently changed by the
use of CONCRETE-DENSITY, although it is intended to use this command for the
definition of lightweight concrete in the future.
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Concrete-Check – User Manual Command Formats
Command : CONCRETE-DEPTH
Syntax : CONCRETE-DEPTH depth (VERIFY)
Applicable to : All checks
Example : CONCRETE-DEPTH 600.0
CONCRETE-DEPTH 500 VERIFY
Description :
The CONCRETE-DEPTH command allows the user to specify a depth of concrete slab in
millimetres for use in the various checks. Specifying a CONCRETE-DEPTH is obligatory
for analyses that do not interface with an FE system, either directly or through CONCRETE-
ENVELOPE.
When CONCRETE-CHECK is being interfaced with an FE system or with CONCRETE-
ENVELOPE, the slab depth can be defined in one of three ways:
− if no CONCRETE-DEPTH instruction is specified, then the depth will be derived from
the thickness of the FE model elements (or obtained from CONCRETE-ENVELOPE,
which performs similar calculations). It is not permitted to use the TOP-STEEL
command in this instance, since the program is unaware of the section depth in the
analysis at the time it locates the reinforcement;
− if a CONCRETE-DEPTH is defined, the user defined depth value will override any
values obtained from the FE analysis or CONCRETE-ENVELOPE backing files and
will be used consistently throughout the analysis;
− if the VERIFY option is included in the CONCRETE-DEPTH command, a mixture of
FE/ENVELOPE and user-defined depths will be used. The program will obtain a
thickness from the analysis backing files for use in calculations as the slab depth, but
will position any TOP-STEEL defined within the section using the user supplied value
of depth. Since it is important that these depths/thicknesses are similar, CONCRETE-
CHECK prints a warning if they differ by more than 1%.
The principal advantage of specifying a depth value is that it permits the definition of TOP-
STEEL, which is always located relative to the user supplied depth. The advantage of the
VERIFY option is that the depth relative to which this TOP-STEEL is defined is checked
against the slab thickness obtained from the analysis.
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Concrete-Check – User Manual Command Formats
Command : CONCRETE-MODULUS
Syntax : CONCRETE-MODULUS (ulsmod (slsmod (flsmod)))
Applicable to : All limit state checks
Example : CONCRETE-MODULUS 30000
CONCRETE-MODULUS 0 25000 25000
Description :
The CONCRETE-MODULUS command is used to define the modulus of concrete for SLS
and FLS checks as many codes require that these checks be based on linear-elastic properties.
The modulus to use is determined as follows:
− for layered method checks, the stress-strain properties defined on the CONCRETE-
PROPERTIES command are used unless the concrete modulus for the required limit
state is non-zero. If this is the case, linear-elastic properties are assumed using the
appropriate modulus from above as the compressive modulus of the concrete. If a
tensile modulus is also required, this is defined, as usual, via the CONCRETE-
PROPERTIES TENSION command;
− for ULS checks using the strip theory method, the CONCRETE-MODULUS command
has no impact and the BS8 110 type section check producing ultimate moments
remains the same;
− for SLS and FLS checks using the strip theory method, however, and for ULS shear
checks, the above moduli, if non-zero, are used for the compressive stiffness of the
concrete. If any is defined as zero, the compressive modulus used is that from the
CONCRETE-PROPERTIES instruction stress-strain curve at zero strain.
Note that the above moduli are affected by material partial safety factors (i.e. divided by the
relevant mpsf value prior to use). The default at the start of the program is for all moduli to
be set to zero (so that CONCRETE-PROPERTIES stress-strain characteristics will be used).
The command CONCRETE-MODULUS on its own resets all three values to zero.
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Concrete-Check – User Manual Command Formats
Command : CONCRETE-PROPERTIES
Syntax : CONCRETE-PROPERTIES BS8110 fcu pr
CONCRETE-PROPERTIES BS5400 fcu pr
CONCRETE-PROPERTIES DNV89 fck pr
(fcck (fcn (ftk (ftn))))
CONCRETE-PROPERTIES DNV77 fcu pr (fck)
CONCRETE-PROPERTIES NS3473 fck pr
(fcck (fcn (ftk ( ftn))))
CONCRETE-PROPERTIES S474 fcu pr fc' (eu (ec))
CONCRETE-PROPERTIES PARABOLIC fcu pr em0
fmax (e2)
CONCRETE-PROPERTIES LINEAR fcu pr em0 fmax
(e2)
CONCRETE-PROPERTIES RIGOROUS fcu pr em0
(fmax (e1 (e2)))
CONCRETE-PROPERTIES DEFINED fcu pr eda fda edb
fdb (edc fdc ...)
CONCRETE-PROPERTIES TENSION emt (S474) (ftmax)
Applicable to : All checks
Examples : CONCRETE-PROPERTIES BS8110 50.0 0.2
CONCRETE-PROPERTIES S474 50.0 0.2 40.0
CONCRETE-PROPERTIES RIGOROUS 40 0.2 23000 21
CONCRETE-PROPERTIES TENSION 20000.0 1.5 S474
CONCRETE-PROPERTIES DEFINED 50 0.2 -1 0 -0. 0035 0
+ -0.0035 -30 -0.0020 –20 0 0 0.0010 1.5 0.0010 0 1 0
Description :
The CONCRETE-PROPERTIES command allows property data for the unreinforced
concrete material to be created. Such data may be redefined as required, the latest being used
when a DO-CHECKS command is encountered. The default, if no CONCRETE-PROPERTY
command is included in the data, is to define a Grade 50 BS8110 curve with a Poisson’s ratio
of 0.2 and no tension properties.
The first parameter on the instruction is a stress/strain curve type which may be BS8110,
BS5400, DNV77, DNV89, NS3473, S474, PARABOLIC, LINEAR, RIGOROUS,
DEFINED or TENSION. The first ten of these are mutually exclusive and will overwrite
previous compression curve characteristics. The TENSION parameter allows an optional
tension curve to be added or removed (the latter when emt is set to zero), without affecting
the compression curve.
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Concrete-Check – User Manual Command Formats
The following parameters are common to several compression curves:
fcu - concrete grade or characteristic strength of a cube specimen
(MNrn-2);
pr - Poisson's ratio of the concrete slab;
em0 - elastic compression modulus at zero strain (MNm'2);
fmax - maximum compressive stress in the concrete (MNm'2);
e1 - strain beyond which no increase occurs in stress (start of
rectangular section);
e2 - failure (crushing) strain of concrete.
The BS8110, BS5400, DNV77 and PARABOLIC curves all create parabolic/rectangular
compressive stress strain curves. For the PARABOLIC case, if e2 is not given, it defaults to
0.0035. The BS8110, BS5400 and DNV77 curves are created in accordance with BS8110:
Part 1: Figure 2.1 BS5400: Part 4: Figure 1 and DNV(1977): Figure 7.1, respectively. For the
DNV77 curve, fck is taken to be the characteristic cylinder strength. If not given, it defaults
to 0.8 fcu.
The DNV89 and NS3473 curves are linear-parabolic-rectangular in accordance with DNV
(1989); Part 3: Chapter 1: Section 8: C301 (with errata, 1991) and NS3473: 11.3.1. The fck
parameter is the concrete grade or characteristic cube strength. It is equivalent to fcu for
other curves. Other parameters, if not given, are taken from Tables C1 and 5 respectively.
The S474 curve is defined by the expression given in Clause 6.2.2 of S474-94, based on the
value of fc’ on the CONCRETE-PROPERTIES instruction. An ultimate or maximum
crushing strain, eu, may optionally be specified. If not given, this is taken to be 0.003 in
accordance with S474-M1989. Refer to the Theory Manual for more details. The elastic
modulus of concrete, ec, is also optional and is calculated in accordance with Clause 6.2.7 of
the standard if not otherwise specified.
The LINEAR curve is a simplification of the parabolic case with e1 calculated from
(fmax/em0/gamma). The RIGOROUS curve is in accordance with BS8110: Part 2: Figure
2.1. If fmax, el and e2 are not given, they default to 0.8 fcu, 0.0022 and 0.0035, respectively.
The DEFINED curve type allows the user to create his own curve from a series of straight
line segments. These segments connect up to fifty (50) strain/stress (ed/fd) points defined on
the CONCRETE-PROPERTIES command and its continuations. Stresses and strains must be
input using a compression-negative sign convention (see example). The curve should start
from the most compressive (negative) point and become increasingly tensile. Stresses at
strains beyond the first and last defined points are linearly extrapolated from the first and last
segments, respectively.
As mentioned earlier, the TENSION curve is an addition to the above compression curves.
The parameters emt and ftmax represent the tension modulus and maximum tensile (cracking)
strength of the concrete in tension. The TENSION curve is ignored when the compression
curve is DEFINED. By default ftmax 1.0 MNm-2.
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Concrete-Check – User Manual Command Formats
If the S474 option is set for TENSION properties, then the influence of tensile stress in the
concrete between cracks is included in accordance with S474-94, Clause 9.3.4. In this
instance, ftmax is taken to be the cracking strength of concrete and defaults to 0.4λ√fc'. The
value of λ depends on concrete density in accordance with Clause 6.4.2 of the standard.
Concrete density may be specified by the CONCRETE-DENSITY instruction. For more
details, refer to the Theory Manual.
None of the above parameters contain any reference to material partial safety factors, which
should be entered on a separate MATERIAL-PARTIAL-SAFETY-FACTORS command.
Values of working stress, etc will be reduced accordingly for any factors given. The
definition of these factors need not precede the definition of the curve so that MATERIAL-
PARTIAL-SAFETY-FACTORS and CONCRETE-PROPERTIES commands may be input
in any order.
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Concrete-Check – User Manual Command Formats
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Concrete-Check – User Manual Command Formats
Command : CONCRETE-S-N-CURVE
Syntax : CONCRETE-S-N-CURVE cccycles ctcycles
Applicable to : Fatigue Checks
Example : CONCRETE-S-N-CURVE
Description :
The CONCRETE-S-N-CURVE command allows the creation of S-N curves for the concrete
of the slab.
Two curves are used for concrete as follows:
− for concrete cycling in compression - compression:
Log10N = cccycles * (1-Smax/(α.fc/γc)) / (1-S min/(α.fc//γc))
− for concrete cycling in compression - tension:
Log10N = ctcycles * (1- Smax /(α.fc/γc))
where all symbols are as given in the Theory Manual.
At program start up, cccycles and ctcycles default to 10.0 and 8.0 respectively. Concrete
cycling in tension-tension is considered not to accumulate damage.
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Concrete-Check – User Manual Command Formats
Command : CONCRETE-STRESS-REDUCTION
Syntax : CONCRETE-STRESS-REDUCTION (ON / OFF / NS3473 / S474)
Applicable to : All Checks
Examples : CONCRETE-STRESS-REDUCTION ON
CONCRETE-STRESS-REDUCTION S474
Description
When this option is enabled, the design compressive stress-strain curve for concrete is
adjusted in accordance with the equations defined in either Norwegian Standards or Canadian
Standards.
Option NS3473 adjusts the stress-strain curve using the following equation, which is taken
from NS3473: Section 12.52:
f = 1 / ( 0.8 + 100 ε) ≤ 1.0
where f is a factor to apply to the stress ordinates of the compressive part of the
curve;
ε is the principal tensile strain.
If instead, option S474 is selected, the curve is modified using the equation defined in CSA
S474 - 94: Section 6.3.4:
f = 1 / ( 0.8 + 170 ε) ≤ 1.0
where f and s are as above.
Use of this command also causes a greater number of envelope extreme combinations to be
analysed. Refer to the Theory Manual for further details.
The two options ON/OFF enable/disable adjustment of the stress-strain curve, whilst
maintaining a record of the currently selected code. The command with no parameters is
equivalent to ON. In the case where no code has been defined previously, the ON instruction
defaults to the NS3473 equation.
The default at the start of the program is for no reduction of the stress-strain curve, i.e OFF.
This reduction capability may be used irrespective of the type of concrete curve selected
using the CONCRETE-PROPERTIES command (i.e. an NS3473 curve is not required).
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Concrete-Check – User Manual Command Formats
Command : CRACK-WIDTHS
Syntax : CRACK-WIDTHS (ON/OFF)
Applicable to : Serviceability Checks
Example : CRACK-WIDTHS
CRACK-WIDTHS OFF
Description :
The CRACK-WIDTHS command controls whether or not crack width calculations will be
performed in accordance with the selected SERVICE-CHECK code or standard. When this
command is ON and serviceability code checks are enabled, crack width calculations will be
performed and compared with acceptable limits at the same time as other selected checks.
The default for CRACK-WIDTHS is ON. CRACK-WIDTHS with no parameters is taken as
CRACK-WIDTHS ON.
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Concrete-Check – User Manual Command Formats
Command : DATA-CHECK-ONLY
Syntax : DATA-CHECK-ONLY
Applicable to : All Checks
Example : DATA-CHECK-ONLY
Description :
The DATA-CHECK-ONLY command is identical to the CODE-CHECK-OFF instruction
and disables code checking of stresses when a DO-CHECKS instruction is encountered.
Only data checking will be performed when a DO-CHECKS command is encountered while
this command is current.
Checking may be switched back on with the CODE-CHECK or CODE-CHECK ON
commands. The default at program start up is to enable code-checks.
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Concrete-Check – User Manual Command Formats
Command : DATUM
Syntax : DATUM vectorx vectory vectorz
Applicable to : All limit state checks
Example : DATUM 1.0 1.0. 0.0
Description :
The DATUM command is used to specify a datum relative to which locations around or
along a section may be defined. The command is therefore currently only available for
structures modelled using solid elements where load components are to be obtained directly
from an FE analysis.
The command is optional. If given, it requires a vector to be specified by inputting the
projections of the vector on the global structure (or substructure) X, Y and Z axes. For
example, the vector 0.0, 1.0, 0.0 specifies a vector in the Y direction.
The above vector is used along with the normal or axis definition for a surface (see
SURFACE command) to define a datum plane. For this reason, the only restraint on the
specification of a datum vector is that it should not be collinear with the normal or axis
definition of the current surface.
The datum and surface definition define the reference axes relative to which locations on a
section may be defined. Refer to the SECTION command for the definition of locations and
to Section 4.10 for general details of section definition.
If the DATUM card is not given, the default vector is in the global X direction (1.0, 0.0, 0.0).
In the current version of the program, for cylindrical and conic surface definitions, there is a
restriction that the datum plane should not intersect any elements. All elements can therefore
be defined as being on the positive side of the datum.
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Concrete-Check – User Manual Command Formats
Command : : DEBUG
Syntax : DEBUG OFF/(level routine (values ---))
Applicable to : All checks
Examples : DEBUG OFF
DEBUG OFF STRULS
DEBUG 2 LAYSOL 2A 2.2 2.9 -1.6
Description :
The DEBUG command may be used to force the program to monitor progress through
selected routines. It is only of use to users who are familiar with the internal operation of the
program and should be used with care, as it can produce a considerable amount of output.
The debug level has different effects depending on the routine to be checked. A debug level
over ninety-nine forces the routine to overwrite certain arguments with the debug values
specified on the end of the line. DEBUG OFF cancels all debugging for all routines.
DEBUG OFF with a routine name cancels debugging for that routine only.
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Concrete-Check – User Manual Command Formats
Command : DEFORMATION-LOADS
Syntax : DEFORMATION-LOADS type (1state) nx ny nxy nyz
DEFORMATION-LOADS RECOVER number
DEFORMATION-LOADS ANALYSIS data
DEFORMATION-LOADS OFF
Applicable to : All limit state checks.
Examples : DEFORMATION-LOADS MAXIMUM STRENGTH 1.0 1.1 0.5
+ -0.15 0.4 -0.1 0.008 0.001
DEFORMATION-LOADS RECOVER 503
DEFORMATION-LOADS ANALYSIS 3
DEFORMATION-LOADS OFF
Description :
The DEFORMATION-LOADS command is used to define forces and moments on a
concrete section resulting from deformation type loadings, e.g. thermal, settlement, etc.
The eight load components (NX, NY, NXY, MX, MY, MXY, NXZ, NYZ) are converted
directly to equivalent strains and superimposed onto the equilibrium strain field
produced by other loadings input via ENVELOPE and PRESTRESS commands. This is
explained in more detail in Section 2.8 and the Theory Manual.
To enable the deformational strains to be evaluated, the concrete modulus and Poisons
ratio of the original analysis must be specified using the associated DEFORMATION-
PROPERTIES command.
The type of the loads can be one of the following:
MAXIMUM specifies the maximum envelope of direct deformational loads
NX, NY, NXY, deformational moments MX, MY, MXY and
deformational shear loads NXZ, NYZ;
MINIMUM defines the corresponding minimum envelope for the eight load
components;
DIRECT specifies that both the maximum and minimum envelope are to
assume the accompanying values.
If only a. maximum or minimum envelope is specified, the other extreme defaults to the
same value. The units of direct force, moment and shear for this form of the command
are MN per metre width, MNm per metre width and MN per metre width respectively.
Separate deformational loads can be associated with the ULS and SLS limit states by
specifying STRENGTH or SERVICE for the optional parameter lstate. If lstate is
omitted, the specified loads will apply to checks for both limit states.
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Concrete-Check – User Manual Command Formats
The command takes a different form when the loads are to be obtained from the backing files
of an FE system. This can be achieved in two ways:
RECOVER this is used when the load envelopes are to be obtained from an FE analysis
post-processed using CONCRETE-ENVELOPE. The parameter number
specifies the envelope number to use for deformation loads i.e. the value
for the ENVELOPE field of the keyed filing system (see section 4.9);
ANALYSIS is used when the loads are to be obtained directly from the FE analysis
results. The accompanying data is specific to the FE system and is
described in the appropriate appendix. In addition a SUPER-ELEMENT
command and some form of panel or section definition, to identify the
location, will also be required.
The final form of the command, DEFORMATION-LOADS OFF, is used to terminate the
imposition of deformational loading on the section under consideration. This command resets
the maximum and minimum deformational load envelopes for all eight components and both
limit states to zero. If at a later stage deformational loads are again required, then the relevant
envelopes will have to be redefined (redefinition of the DEFORMATION-PROPERTIES is
not necessary)
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Concrete-Check – User Manual Command Formats
Command : DEFORMATION-PROPERTIES
Syntax : DEFORMATION-PROPERTIES eval mu
Applicable to : All limit state checks.
Examples : DEFORMATION-PROPERTIES 30000 0.2
Description:
The DEFORMATION-PROPERTIES command is used to specify the values for Young's
modulus and Poison's ratio used during the analysis of the deformational loadings being input
via the DEFORMATIONAL-LOADS command. This command must be present if
DEFORMATION-LOADS are specified. There is no default for this command.
The command requires two parameters, eval specifies the Young's modulus value (in MNm-
2
) and mu defines Poisson's ratio. The use of these parameters in generating equivalent
deformational strain is described in the Theory Manual.
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Concrete-Check – User Manual Command Formats
Command : DO-CHECKS
Syntax : DO-CHECKS
Applicable : All checks
Example : DO-CHECKS
Description :
The DO-CHECKS command instructs the program to temporarily stop reading input data and
to start performing code checks using data defined by previous instructions.
CONCRETE-CHECK will initially perform a data check on the input data to check that it is
consistent. The requested checks will then be performed if;
− there have been no errors in the data input or cross check;
− a DATA-CHECK-ONLY or CODE-CHECK OFF command has not been issued;
− the appropriate class checks have been enabled using ANALYSE-NODE-CLASSES.
When the DO-CHECKS command is complete, the program returns to input further
commands from the current input device.
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Concrete-Check – User Manual Command Formats
Command : ECHO
Syntax : ECHO (ON/OFF)
Applicable to : All checks
Examples : ECHO
ECHO OFF
Description :
The ECHO command controls echo of input commands to the output stream or file. When
this command is ON, each input instruction is attributed a line number and printed as it is
encountered.
The default for ECHO is ON. The LIST-INPUT-DATA command may be used to control the
output of interpreted data in addition to the simple command echo. ECHO with no
parameters is taken as ECHO ON.
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Concrete-Check – User Manual Command Formats
Command : END
Syntax : END
Applicable to : All checks
Examples : END
Description
The END command is identical to the STOP command and has the action of terminating the
current run (even if further data exists in the input file), closing all files and returning to the
operating system.
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Concrete-Check – User Manual Command Formats
Command : ENVELOPE
Syntax : ENVELOPE MAXIMUM (STRENGTH/SERVICE)
nx ny nxy ---- nxz nyz
ENVELOPE MINIMUM (STRENGTH/SERVICE)
nx ny nxy ---- nxz nyz
ENVELOPE DIRECT (STRENGTH/SERVICE)
nx ny nxy --- nxz nyz
ENVELOPE RECOVER number
ENVELOPE ANALYSIS data ----
Applicable to : Ultimate Strength checks
Serviceability checks
Examples : ENVELOPE MAXIMUM 1.0 2.0 0.3 0.15 0.14 0.06
+ 0.02 -0.01
ENVELOPE RECOVER 13
ENVELOPE DIRECT SERVICE
+ -1.31 -0.22 0.05 0.162 -0.381 -0.011 0.03 0.04
Description :
The ENVELOPE command is used to recover or create envelopes of the eight basic
load components (NX, NY, NXY, MX, MY, MXY, NXZ, NYZ) for use in the ultimate
strength and service limit state checks.
ENVELOPE with a MAXIMUM, MINIMUM or DIRECT parameter allows the user to
directly input maximum and minimum load envelopes. Direct loads (NX, NY, NXY, NXZ,
NYZ) are input in MN per metre width. Moments are applied as MNm per metre width.
Maximum and minimum envelopes may be defined separately. However, if only one
envelope (maximum or minimum) is defined in the data, the other will be made the
same. Specifying DIRECT will always create both maximum and minimum values
irrespective of whether previous MAXIMUM or MINIMUM envelopes have been
given. The program will rectify cases where the minimum envelope for any load
component is greater than the maximum. Continuation lines can be used as necessary.
Input envelopes may be associated with STRENGTH or SERVICE checks by means of
the second parameter. If this keyword is omitted, the envelope will apply to both
strength and service checks.
A parameter of RECOVER causes envelopes to be recovered from backing files written
by the CONCRETE-ENVELOPE program. The next item of data specified is the
envelope 'number' as used in CONCRETE-ENVELOPE when the envelopes were
created. A keyed filing system must be defined if envelopes are to be recovered. Refer
to Section 4.9 for details. A SUPER-ELEMENT command must also be present.
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Concrete-Check – User Manual Command Formats
Use of the ANALYSIS parameter signifies that an envelope is to be created using load
components taken directly from the FE system to which CONCRETE is interfaced.
Subsequent data is dependent on this FE system and is described in the appropriate appendix.
The SUPER-ELEMENT command and some form of panel or section definition must be
given in the data if this option is to be used.
Problems may arise in the layered solution if all of NX, NY amd NXY, are zero. If this is the
case, very small values should be substituted.
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Concrete-Check – User Manual Command Formats
Command : ENVELOPE-NAME
Syntax : ENVELOPE-NAME (description)
Applicable to : Ultimate strength checks
Serviceability checks
Example : ENVELOPE-NAME SURVIVAL CONDITION
Description :
The ENVELOPE-NAME instruction is used to associate a description with the envelope
being analysed. This description will appear in the main output when referring to the
envelope.
The envelope description may be up to thirty characters long, including embedded blanks.
When used as a post-processor to an FE system via CONCRETE-ENVELOPE, an envelope
name will be picked up from the backing files. In the stand-alone mode or when used to
directly post-process FE analysis results, there is no such default envelope name.
Whichever mode of operation is current, this command will overwrite any default setting
until switched off with an ENVELOPE-NAME command with no arguments.
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Concrete-Check – User Manual Command Formats
Command : ENVELOPE-NUMBER
Syntax : ENVELOPE-NUMBER number
Applicable to : Ultimate strength checks
Serviceability checks
Example : ENVELOPE-NUMBER 6
Description :
The ENVELOPE-NUMBER command is used to identify the envelope in the main output.
The command should be used for identification purposes only when CONCRETE--CHECK
is being used as stand-alone program or is being interfaced directly with an FE analysis.
When used as a post-processor via CONCRETE-ENVELOPE, the envelope number on the
ENVELOPE command defines the current envelope and is used both to recover envelopes
from the backing files and to identify output.
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Concrete-Check – User Manual Command Formats
Command : FATIGUE-CHECK
Syntax : FATIGUE-CHECK (OFF/ON)
Applicable to : Fatigue Checks
Example : FATIGUE-CHECK OFF
FATIGUE-CHECK
Description :
The FATIGUE-CHECK command specifies whether fatigue checking is to be performed or
not. By default, at program start up, fatigue checking is off.
FATIGUE-CHECK or FATIGUE-CHECK ON may be used to switch on fatigue checking
at the next DO-CHECKS command. Fatigue checking may be switched back OFF with a
FATIGUE-CHECK OFF command.
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Concrete-Check – User Manual Command Formats
Command : FATIGUE-CYCLE
Syntax : FATIGUE-CYCLE occurs COMPLEX steps scase
(rcase(icase))
FATIGUE-CYCLE occurs STEPPED casel case2 ----
Applicable to : Fatigue checks
Examples : FATIGUE-CYCLE 2006213 COMPLEX 3 12 10012
FATIGUE-CYCLE 6211 STEPPED 201 202 203 204
Description :
The FATIGUE-CYCLE command is used to specify which load combinations are used in the
fatigue checks to represent a single load cycle, and how many occurrences of this cycle are
expected in a single year. At least one command of this type must be specified for any fatigue
checking run. Subsequent commands add further cycles to the cumulative damage
calculations until a FATIGUE-RESET command is encountered.
Each command represents one cycle. The 'occurs' parameter specifies how many occurrences
of this cycle will be considered IN ONE YEAR.
There are two ways of defining a cycle:
− the cycle may be represented in COMPLEX form as static, real and imaginary
components. For load combinations obtained directly from a particular FE system, the
exact input data is explained in the appropriate appendix. Depending on the FE system
in use, up to three individual load case numbers may be required. If loads are defined
by direct input in the data file, then the user should provide static, real and imaginary
combinations and will require all three case numbers. The complex representation will
be used to develop loads at a user-specified number of 'steps' through the load cycle.
The 'steps parameter should be an integer greater than one;
− the cycle may be STEPPED signifying a time history definition of loading by providing
individual load combinations at each step through the cycle. Each step is represented by
one combination. Between two and twenty-five individual combinations may be
specified.
The user should also refer to the STATIC-COMBINATION command which permits a
further static load combination to be applied to all cycles. The COMBINATION card defines
the source of all combinations to use in CONCRETE-CHECK.
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Concrete-Check – User Manual Command Formats
Command : FATIGUE-DATA
Syntax : FATIGUE-DATA ccsum (rbsum (ON/OFF))
Applicable to : Fatigue checks
Examples : FATIGUE-DATA 0.33 0.33
FATIGUE-DATA 0.2 1.0 ON
Description :
The FATIGUE-DATA command allows the specification of parameters used in the fatigue
limit state checks. The following may be specified:
ccsum - the miner's sum to be used for concrete, defaults to
0.2;
rbsum - the miner's sum to be used for reinforcement, defaults
to 1.0;
ON/OFF - ON if low amplitude, high cycle fatigue is to be modified in
accordance with DnV (1989) or NS 3473 (1989). OFF if it is
not be modified. If it is set ON, the number of cycles to failure
is modified in accordance with the Theory Manual. The default
for this parameter is OFF.
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Concrete-Check – User Manual Command Formats
Command : FATIGUE-LIFE
Syntax : FATIGUE-LIFE years
Applicable to : Fatigue checks
Examples : FATIGUE-LIFE 30.0
Description :
The FATIGUE-LIFE command specifies the required fatigue life in years which the
structure is expected to endure.
By default, the required fatigue life is sixty years.
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Concrete-Check – User Manual Command Formats
Command : FATIGUE-RESET
Syntax : FATIGUE-RESET
Applicable to : Fatigue checks
Examples : FATIGUE-RESET
Description :
The FATIGUE-RESET command resets all load cycles created so far and allows the user to
restart their entry from scratch.
This card cancels the occurrence and load combination references made on all previous
FATIGUE-CYCLE commands. The command does not affect the STATIC-
COMBINATION or any data set up on COMBINATION commands. Combinations created
on any COMBINATION commands will still be available for later FATIGUE-CYCLES.
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Concrete-Check – User Manual Command Formats
Command : FINISH-PLOT
Syntax : FINISH-PLOT
Applicable to : All limit states checks
Examples : FINISH-PLOT
Description :
The FINISH-PLOT command is used to terminate the writing of CONCRETE-CHECK
results to plot file and to close this file so that it can subsequently be accessed by the utility
plot program (PLOTIT). Use of this command should not be confused with the more
general capabilities of the CONCRETE-PLOT program, which requires that results be
stored using the WRITE command.
Refer to the BEGIN-PLOT command for more details of the plot facility and to Section B.3
for sample output.
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Concrete-Check – User Manual Command Formats
Command : GROUP
Syntax : GROUP set
Applicable to : All limit states checks
Examples : GROUP 31
Description
The GROUP command is used to specify the FE analysis group or set number containing all
elements on which checks are to be based. The SET instruction is identical to GROUP and
either may be used freely.
The GROUP or SET commands are used if CONCRETE-CHECK is to access the results
from an FE analysis, either directly or indirectly via a CONCRETE-ENVELOPE analysis. It
is not used if data is input directly to the data file, but should be specified anyway, for
identification of output.
When CONCRETE-CHECK takes loads directly from the FE analysis, the set specified
should contain all shell or solid elements needed to define the panel or section under
analysis. The command must be present even if a single node or location is to be processed.
When CONCRETE-CHECK recovers envelopes from CONCRETE-ENVELOPE, the set
number is important if it was used in the definition of the key system for storage of
envelopes. Furthermore, a set or group number of zero may be used to specify that a global
envelope is to be recovered.
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Concrete-Check – User Manual Command Formats
Command : IMPLOSION-CHECK
Syntax : IMPLOSION-CHECK (OFF/ON)
Applicable to : Implosion checks
Example : IMPLOSION-CHECK
IMPLOSION-CHECK OFF
Description
The IMPLOSION-CHECK instruction is used to specify that cylinder implosion checks are
to be performed at subsequent DO-CHECKS instructions until overridden by an
IMPLOSION-CHECK OFF instruction.
IMPLOSION-CHECK with no following data is equivalent to IMPLOSION-CHECK ON.
If no IMPLOSION-CHECK instruction is used, IMPLOSION checks will not be
performed.
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Concrete-Check – User Manual Command Formats
Command : IMPLOSION-CYLINDER.
Syntax : IMPLOSION-CYLINDER length radius (width(fixity))
Applicable to : Implosion checks
Examples : IMPLOSION-CYLINDER 150.0 15.0
IMPLOSION-CYLINDER 95.0 12.0 15.621 1.0
Description :
The IMPLOSION-CYLINDER command allows the specification of a cylinder geometry
for subsequent implosion checks.
The cylinder 'length' and mean 'radius' should always be input. The cylinder 'width' is used
to define a curved panel (partial cylinder) and should be less than the cylinder
circumference. If 'width' is not given, a full cylinder is assumed.
The edge 'fixity' parameter is only required if 'width' is non-zero. It references the edge
fixity of a curved panel required by Chrapowicki to determine the modified buckling
strength under pressure loading. The program will interpolate between edge fixity of 0.0
(simple supported) and 1.0 (fixed).
The cylinder length, width and radius should be input in metres. For the purposes of
reinforcement orientation, the slab X" direction is considered to be along the axis of the
cylinder, whilst the Y" direction is circumferential.
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Concrete-Check – User Manual Command Formats
Command : IMPLOSION-IMPERFECTIONS
Syntax : IMPLOSION-IMPERFECTIONS eo
Applicable to : Implosion checks
Example : IMPLOSION-IMPERFECTIONS 75.0
Description :
The IMPLOSION-IMPERFECTIONS command allows the input of a maximum
imperfection in mm for the evaluation of imperfection bending moments from a cylinder
implosion check.
By default, if this command is not given, an imperfection of radius/200 is assumed.
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Concrete-Check – User Manual Command Formats
Command : IMPLOSION-LOADS
Syntax : IMPLOSION-LOADS pressure (axial(bending(shear(torsion))))
Applicable to : Implosion Checks
Examples : IMPLOSION-LOADS 0.232
IMPLOSION-LOADS 0.232 -1.263 -3.121 0282 0.211
Description :
The IMPLOSION-LOADS command allows the specification of a set of loads to apply to
the cylinder in a cylinder implosion check.
The following loads may be applied:
pressure - acting external pressure (MNm-2);
axial - longitudinal load per unit width due to axial load on
cylinder (MN per metre);
bending - longitudinal load per unit width due to bending
moment on cylinder (MN per metre);
shear - shear flow due to shear load on cylinder (MN per
metre);
torsion - shear flow due to torsion on cylinder (MN per metre).
Any values not given are taken as zero. The 'axial' and 'bending' loads are compression-
negative, but the pressure is positive for external pressure. The sign of the shear loads is
irrelevant.
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Concrete-Check – User Manual Command Formats
Command : INTERACTIVE
Syntax : INTERACTIVE
Applicable to : All Checks
Example : INTERACTIVE
Description :
The INTERACTIVE command allows the user to switch to interactive input and causes
CONCRETE-CHECK to issue an
INSTRUCTION??
prompt when processing of the previous instruction is complete. The command is of use on
systems that cannot sense that the program is being run interactively.
This command is not available on most computer types. Its use should be checked with the
authors.
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Concrete-Check – User Manual Command Formats
Command : KEY-FIELDS
Syntax : KEY-FIELDS keyl (key2 ---- keyn)
Applicable to : All Checks
Examples : KEY-FIELDS KEY1
KEY--FIELDS CASE GROUP NODE
Description :
The KEY-FIELDS instruction allows the definition of an index system for recovery of
envelope results. Up to fifteen KEY-FIELDS may be defined. These fields may be
previously defined symbols (via NEW-SYMBOL), or may be any of the following reserved
symbols:
NODE - node number or location
LOCATION - node number or location
GROUP - group/set number
SET - group/set number
CLASS - class number
SECTION - section number
ENVELOPE - envelope number.
For the keyed filing system to be fully defined, a set of ranges must be defined for each
field on this card. The KEY-RANGES card is provided for this purpose and it is normal
that a KEY-RANGES command will immediately follow KEY-FIELDS,
A full description of the keyed filing system in use by the CONCRETE suite is given in
Section 4.9.
Note that there is no default for this command. It must be present in the input data if
envelopes are to be retrieved from a CONCRETE-ENVELOPE backing file or written to a
CONCRETE-CHECK results backing file.
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Concrete-Check – User Manual Command Formats
Command : KEY-RANGES
Syntax : KEY-RANGES min1 max1 (min2 max2 -----minn maxn)
Applicable to : All Checks
Examples : KEY-RANGES 1 100
KEY-RANGES 1 4 1 50 0 10000
Description :
The KEY-RANGES command allows numerical ranges to be assigned to the fields created
by a KEY-FIELDS instruction. Together, these two cards are used to define a keyed filing
system for the storage of CONCRETE-ENVELOPE results.
Ranges are specified by minimum and maximum values for each field. The number and
order of the ranges must correspond to those given on a KEY-FIELDS instruction. A KEY-
FIELDS instruction must precede KEY-RANGES.
Note that if the reserved symbols NODE or LOCATION are used on a KEY-FIELDS
instruction, then the corresponding range should start at zero, to allow storage of class
envelopes (node 0) as well as node or location envelopes. The SET, GROUP and CLASS
reserved symbols should also have minimum values of 0, if global envelopes are required.
A full description of the keyed filing system is included in Section 4.9 of this manual.
The default range is zero to zero for each field giving a trivial maximum key of one. In
general, therefore, a KEY-RANGES card is always required if KEY-FIELDS have been
specified.
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Concrete-Check – User Manual Command Formats
Command : LIST-INPUT-DATA
Syntax : LIST-INPUT-DATA (ON/OFF)
Applicable to : All checks
Examples : LIST-INPUT-DATA
LIST-INPUT-DATA OFF
Description :
The LIST-INPUT-DATA instruction allows selective printing of interpreted input data as
commands are read in. The printout produced by this command is rather more detailed than
the simple data echo produced by the ECHO command,
The default for LIST-INPUT-DATA is ON.
LIST-INPUT-DATA with no parameters is taken as meaning LIST-INPUT-DATA ON.
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Concrete-Check – User Manual Command Formats
Command : MATERIAL-PARTIAL-SAFETY-FACTORS
Syntax : MATERIAL-PARTIAL-SAFETY-FACTORS (lstate) gammac
gammar gammap (gammas)
Applicable to : All checks
Examples : MATERIAL-PARTIAL-SAFETY-FACTORS 1.50 1,15 1.15
1.25
MATERIAL-PARTIAL-SAFETY-FACTORS STRENGTH
1.90 1,20 1.20
Description :
The MATERIAL-PARTIAL-SAFETY-FACTORS command allows partial safety factors to
be specified for concrete (gammac), reinforcement bars (gammar), prestress tendons
(gammap) and for shear checks (gammas). The shear check value is only applicable to
codes that require it (currently BS8110 and BS5400). It may be omitted for other rules.
The lstate parameter may be used to define the limit state for which these factors apply.
lstate may take the value STRENGTH, SERVICE or FATIGUE, restricting the command to
modifying only the ULS, SLS or FLS values respectively. If not given, the accompanying
m.p.s.f values are applied to all three limit states.
The command may be used repeatedly within a data file, The stress-strain curves for each
material are re-calculated when a DO-CHECKS instruction is encountered. This ensures
that the current m.p.s.f values and material properties are used. There is no restriction on the
order of MATERIAL-PARTIAL-SAFETY-FACTORS and REBAR-PROPERTIES
commands.
At program start up, the following factors are set for all three limit states by default,:
gammac = 1.00, gammar = 1,00, gammap = 1.00, gammas = 1.00
IMPLOSION-CHECK and PANEL-STABILITY-CHECK use the values currently
specified for STRENGTH (ULS).
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Concrete-Check – User Manual Command Formats
Command : MAXIMUM-ERRORS
Syntax : MAXIMUM-ERRORS maxerr
Applicable to : All checks
Examples : MAXIMUM-ERRORS 10
Description :
The MAXIMUM-ERRORS command is used to control the number of input errors that are
allowed before further efforts to process input data are abandoned. By default, the
maximum number of errors is set to twenty.
This command allows input data with errors to be processed up to an acceptable level of
error before input is terminated. It does not control code checks. If there are any input errors
when a DO-CHECKS instruction is encountered, code checking will be abandoned (but
further input data will subsequently be processed up to the maximum error count).
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Concrete-Check – User Manual Command Formats
Command : METHOD
Syntax : METHOD STRIP (angle (miter (contol)))
METHOD LAYER (nlayers (miter (contol (nskip
(stiff1---- stiff6 (weight1 ---- weight6
(stiff7---- stiff9 (weight7----weight9))))))))
Applicable to : All limit state checks
Examples : METHOD STRIP 45.0
METHOD LAYER 10 200 0.02 5 1 1 1 0 0 0
Description
The METHOD command instructs the program to use a specified method to analyse the
reinforced/prestressed slab locations being checked. Refer to Section 2.3 for details of the
BS8110 strip theory and the more general layered approaches. Both methods accept a
number of parameters:
angle - the angle (default zero) of the BS8110 strip theory section relative to
the slab axes. Refer to Section 4.3 for the sign convention.
miter - the maximum number of iterations allowed in either method. By
default, this is set to fifty, but may be changed by the user if the
program indicates that convergence was not obtained after this number
of iterations;
nlayers - the discrete number of layers into which the concrete slab is divided for
the layered method. By default, this is ten, which should be acceptable
for most purposes;
contol - convergence tolerance for the strip or layered methods. See the Theory
Manual for full details. Set to 0.01 by default;
nskip - a skip parameter for the layered method set to five by default. Refer to
the Theory Manual for more details;
stiffn - for the layered method, stiffness weights to adjust the initial stiffness
for each load component, NX, NY, NXY, MX, MY, MXY (also NXZ, NYZ,
NZ, if triaxial shear checks are requested) in the iteration procedure.
Refer to the Theory Manual for a more detailed explanation. These
values default to unity;
weightn - for the layered method, weights to be applied for each load component
in the calculation of convergence. By default, all values are one. Refer
to the Theory Manual for details.
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Concrete-Check – User Manual Command Formats
Command : NEW-SYMBOL
Syntax : NEW-SYMBOL symbol (value)
Applicable to : All checks
Examples : NEW-SYMBOL KEY1
NEW-SYMBOL KEY2 31
Description :
The NEW-SYMBOL command is used to create symbols for use in the KEY-FIELDS
instruction to define the keyed filing system. Numerical values may optionally be defined
by this command or by the SYMBOL-VALUE instruction. The default value for a symbol
is zero.
The following symbols are reserved and should not be used:
NODE, GROUP, LOCATION, SET, CLASS, SECTION, ENVELOPE.
Apart from the reserved symbols, the NEW-SYMBOL command must be used to define a
symbol before it can be referenced by a KEY-FIELDS instruction, or be assigned a value by
SYMBOL-VALUE.
Section 4.9 contains a full description of the CONCRETE suite keyed filing system.
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Concrete-Check – User Manual Command Formats
Command : ORIGIN
Syntax : ORIGIN x y z
Applicable to : All checks
Example : ORIGIN 3.0 3.0 -10.0
Description :
The ORIGIN command defines the origin of a surface used to locate a section. The
command is therefore currently only available for structures modelled using solid elements
and where load components are to be obtained directly from the FE analysis.
By default, the origin of any surface is 0.0, 0.0, 0.0 at program start up. This is the origin of
the structure (or superelement if a substructured analysis is being used). The ORIGIN
command may be used, however, to move the origin of a surface from the global origin to a
new position. The command is optional.
ORIGIN commands are not cumulative. When a DO-CHECKS command is encountered, the
latest origin (if any) is used in the surface and hence section definition.
The units of the ORIGIN command should be the same as those of the FE model.
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Concrete-Check – User Manual Command Formats
Command : OUTPUT-LEVEL
Syntax : OUTPUT-LEVEL SUMMARY/BRIEF/INTERMEDIATE/
DETAILED(BRIEF/FULL)
Applicable to : All limit state checks
Examples : OUTPUT-LEVEL SUMMARY
OUTPUT-LEVEL DETAILED BRIEF
Description :
The OUTPUT-LEVEL command allows control over the level of printout produced by
CONCRETE-CHECK for the limit state checks. The first parameter may be any of the
following:
SUMMARY: produces summary file output only, no main output per check.
BRIEF: produces only the check header and results, no details of the
actual checks in the output.
INTERMEDIATE: for fatigue limit state, restricts the printout to damage
cumulation per cycle only.
DETAILED: provides maximum output. In this case, the second parameter
may be used to control the level of output from the individual
section checks. BRIEF shows only whether the check was
successful or not. FULL provides detailed information about
the check.
The output levels remain in force until redefined. Output levels do not affect the writing of
results to backing file for subsequent access by CONCRETE-PLOT.
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Concrete-Check – User Manual Command Formats
Command : PANEL
Syntax : PANEL SWEEP/SAMPLE (angtol)
Applicable to : All checks
Examples : PANEL SWEEP
PANEL SAMPLE
Description :
This command applies only to structures where the concrete substructure is modelled using
thick or thin shell elements and where load components are to be obtained directly from an
FE analysis.
SWEEP selects all nodes in a set for future processing. When a DO-CHECKS instruction is
encountered, the program will scan the currently selected plate element set (SET or
GROUP) and identify and classify (see ANALYSE-NODE-CLASSES) all nodes on the
plate. If checking is enabled (CODE-CHECK ON), the program will proceed to check and
report these nodes.
SAMPLE is similar to SWEEP in that it causes CONCRETE-CHECK to scan the current
SET or GROUP when a DO-CHECKS instruction is encountered. However, whereas
SWEEP will then classify and select all nodes found for checking, SAMPLE will select
only a small subset of the classified nodes, namely:
- all corner nodes;
- mid edge nodes.
If checking is enabled (CODE-CHECK ON), the program will proceed to evaluate and
store envelopes for this sample of nodes.
The optional angular tolerance is used when finding corner nodes on the panel. Most
corners are identified topologically (by element connectivity). However, inside corners and
other complex geometries may not be identified this way and are found by checking the
angular change around the boundary. When this angular change exceeds angtol, a further
corner is recorded.
This command is overwritten by the SECTION, SELECT and CLEAR-SELECT
commands, which allow other methods of node selection.
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Concrete-Check – User Manual Command Formats
Command : PANEL-DIMENSIONS
Syntax : PANEL-DIMENSIONS length width (fixity)
Applicable to : Panel stability checks
Examples : PANEL-DIMENSIONS 15.0 10.0
PANEL-DIMENSIONS 20.0 7.5 1.0
Description :
The PANEL-DIMENSIONS command allows the specification of a flat panel geometry for
subsequent panel stability checks.
The 'length' and 'width' should always be input. The remaining parameter is an edge 'fixity'
that may vary between 0.0 (simply supported) and 1.0 (clamped). If not given, 'fixity' is
taken as 0.0.
The panel length and width should be specified in metres. The panel is assumed to be
'length' long in the X" direction, and 'width' long in the Y" direction. The Z" direction is
therefore assumed to be the through-thickness direction. This definition is of use when
defining loads. These directions are important in the definition of loads and reinforcement.
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Concrete-Check – User Manual Command Formats
Command : PANEL-IMPERFECTIONS
Syntax : PANEL-IMPERFECTIONS eo
Applicable to : Panel Stability checks
Example : PANEL-IMPERFECTIONS 75.0
Description :
The PANEL-IMPERFECTIONS command allows the input of a maximum imperfection in
mm for the evaluation of imperfection bending moments from a panel stability check,
By default, if this command is not given, an imperfection of the panel diagonal/200 is
assumed,
THIS COMMAND IS NOT CURRENTLY USED.
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Concrete-Check – User Manual Command Formats
Command : PANEL-LOADS
Syntax : PANEL-LOADS pressure (nx(ny(nxy)))
Applicable to : Panel Stability checks
Examples : PANEL-LOADS 0.202
PANEL-LOADS 0.517 -2,621 -3202 1.516
Description :
The PANEL-LOADS command allows the input of prebuckling loads on a flat panel to be
subjected to a panel stability check.
The following loads may be applied:
pressure - uniform pressure loading (MNn-2);
nx - X direction load per unit width (MN per metre);
ny - Y direction load per unit width (MN per metre);
nxy - shear flow (MN per metre).
The nx and ny loads follow the usual compression-negative sign convention. The pressure
load, however, is defined as being positive if it acts on the top face of the panel.
Refer to the PANEL-DIMENSIONS command for a definition of the X and Y panel stress
directions.
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Concrete-Check – User Manual Command Formats
Command : PANEL-STABILITY-CHECK
Syntax : PANEL-STABILITY-CHECK(OFF/ON)
Applicable to : Panel Stability checks
Example : PANEL-STABILITY-CHECK
PANEL-STABILITY-CHECK OFF
Description :
The PANEL-STABILITY-CHECK instruction is used to specify that panel stability checks
are to be performed at subsequent DO-CHECKS instructions until overridden by a PANEL-
STABILITY-CHECK OFF instruction.
PANEL-STABILITY-CHECK with no following data is equivalent to PANEL-
STABILITY-CHECK ON.
If no PANEL-STABILITY-CHECK instruction is used, panel stability checks will not be
performed.
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Concrete-Check – User Manual Command Formats
Command : POST-DEFORMATION-LOADS
Syntax : POST-DEFORMATION-LOADS type (Istate) nx ny nxy… nyz
POST-DEFORMATION-LOADS RECOVER number (ulsfac (slsfac))
POST-DEFORMATION-LOADS ANALYSIS data
POST-DEFORMATION-LOADS OFF
Applicable to : All limit state checks.
Examples : POST-DEFORMATION-LOADS MINIMUM SERVICE 1.0 1.1 0.5
+ -0.15 0.4 -0.1 0.008 0.001
POST-DEFORMATION-LOADS RECOVER 1001 1.4
POST-DEFORMATION-LOADS ANALYSIS 3
POST-DEFORMATION-LOADS OFF
Description:
The POST-DEFORMATION-LOADS command is used to define forces and moments on a
concrete section to be applied after the imposition of deformation type load cases. The eight
load components (NX, NY, NXY, MX, MY, MXY, NXZ, NYZ) specified by this command are
applied to the section after the strain field has been updated by any deformational loadings.
In conjunction with ENVELOPE and DEFORMATION-LOADS this command permits the
sequence of load application to the structure to be represented.
The type of the loads can be one of the following:
MAXIMUM specifies the maximum envelope of direct post-deformational loads NX,
NY, NXY, post-deformational moments MX, MY, MXY and post-
deformational shear loads NXZ, NYZ;
MINIMUM defines the corresponding minimum envelope for the eight load
components;
DIRECT specifies that both the maximum and minimum envelope are to assume
the accompanying values.
If only a maximum or minimum envelope is specified, the other extreme defaults to the
same value. The units of direct force, moment and shear for this form of the command are
MN per metre width, MNm per metre width and MN per metre width respectively.
Separate deformational loads can be associated with the ULS and SLS limit states by
specifying STRENGTH or SERVICE for the optional parameter lstate. If Istate is omitted,
the specified loads will apply to checks relating to both limit states.
The command takes a different form when the loads are to be obtained from the backing
files of an FE system. This can be achieved in two ways:
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Concrete-Check – User Manual Command Formats
RECOVER this is used when the load envelopes are to be obtained from an FE
analysis post-processed using CONCRETE-ENVELOPE. The
parameter number specifies the envelope number to use for post-
deformation loads, i.e. the value for the ENVELOPE field of the keyed
filing system (see section 4.9).
The ULS and SLS loadings in the recovered envelope may be
independently factored by specifying the optional parameters ulsfac and
sisfac respectively. If only ulsfac is specified both loadings are factored
by the specified value.
ANALYSIS is used when the loads are to be obtained directly from the FE analysis
results. The accompanying data is specific to the FE system and is
described in the appropriate appendix. In addition a SUPER-ELEMENT
command and some form of panel or section definition, to identify the
location, will also be required.
The final form of the command, POST-DEFORMATION-LOADS OFF, is used to terminate
the imposition of post-deformation loading on the section under consideration. This
command resets the maximum and minimum deformational load envelopes for all eight
components and all three limit states to zero. If at a later stage post-deformational loads are
required, then the relevant envelopes will have to be redefined.
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Concrete-Check – User Manual Command Formats
Command : PRESTRESS-FACTORS
Syntax : PRESTRESS-FACTORS (lstate) pmax pmin smax smin
Applicable to : Strength checks only
Examples : PRESTRESS-FACTORS 1.25 0.80 1.10 0.90
PRESTRESS-FACTORS SERVICE 1.1 1.0 1.0 1.0
Description :
The PRESTRESS-FACTORS command is used to allocate load partial safety factors for
prestress load cases. These are applied in CONCRETE-CHECK rather than CONCRETE-
ENVELOPE as they are allowed to differ for primary and secondary prestress and for shear
checks.
By default, at the start of the program, all such factors are unity (1.0). The following may
be set by this command:
pmax and pmin - the maximum and minimum factors to apply to primary prestress;
smax and smin - the maximum and minimum factors to apply to secondary prestress;
The lstate parameter is used to define the limit state for which these factors are to apply.
lstate may take the value STRENGTH, SERVICE or FATIGUE, restricting the command
to modifying only the ULS, SLS or FLS values respectively. If not given, the
accompanying prestress factors are applied to all three limit states.
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Concrete-Check – User Manual Command Formats
Command s : PRESTRESS-LOADS
Syntax : PRESTRESS-LOADS TOTAL/SECONDARY DIRECT
nx ny nxy ---- nxz nyz
PRESTRESS-LOADS TOTAL/SECONDARY RECOVER
number
PRESTRESS-LOADS TOTAL/SECONDARY ANALYSIS
data ----
PRESTRESS-LOADS TOTAL/SECONDARY NONE
Applicable to : All limit state checks
Examples : PRESTRESS-LOADS TOTAL DIRECT -1.267 -3.612 -2.076
+ 1.611 0.282 0.316 -2.621 1.011
PRESTRESS-LOADS SECONDARY RECOVER 3
Description :
The PRESTRESS-LOADS command specifies the source of prestress load case loading for
all limit state checks, and optionally allows load data to be input directly.
DIRECT specifies that prestress loading is to be provided by direct input, and specifies the
values to use, Continuation lines may be used to specify all the data. NX, NY, NXY, NXZ and
NYZ loads are input in units of MN per metre width, Moments (MX, MY, MXY) are input as
MNm per metre (MN).
The ANALYSIS, and RECOVER keywords may be used to indicate that prestress data is to
be read directly from an FE analysis results file, or from CONCRETE-ENVELOPE
backing files. Other data is required on the ANALYSIS commands, but this is dependent on
the FE system to which CONCRETE-CHECK is interfaced. The user should refer to the
appendix appropriate to his FE system. The RECOVER command requires the number of
the envelope to be recovered as its argument. CONCRETE-CHECK will take the average
of the max/min service envelope for prestress.
At program start-up, there is no prestress loading. A PRESTRESS-LOADS SECONDARY
NONE command returns to this state.
Either TOTAL or SECONDARY prestress may be created by this command. Refer to
Section 2.7 for a description of the use of prestress in CONCRETE-CHECK.
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Concrete-Check – User Manual Command Formats
Command : PRESTRESS-TENDONS
Syntax : PRESTRESS-TENDONS type material sndata strands
diameter spacing prestress
Applicable to : All checks
Examples : PRESTRESS-TENDONS 5 1 0 10 25.0 300.0 1.0
PRESTRESS-TENDONS 9 6 3 5 25.0 500.0 1.0
Description :
The PRESTRESS-TENDONS command allows a table of prestress tendon geometries to be
created for reference by TOP-STEEL and BOTTOM-STEEL instructions,
The 'type' parameter refers to the entry in the tendon geometry table. Tendon entries may be
added in any order and may be overwritten by successive PRESTRESS-TENDON
commands as required. There is no facility to delete tendon geometries, but they will not be
used if they are not referenced by TOP-STEEL and BOTTOM-STEEL instructions, Up to
9999 tendon geometries may be created and used,
The 'material' parameter refers to an entry in the tendon material property list created by a
TENDON-PROPERTIES command. It is not necessary that the TENDON-PROPERTIES
command should precede any PRESTRESS-TENDONS command, only that correctly cross-
referenced entries be current when a DO-CHECKS instruction is encountered.
The 'sndata' parameter may be used to reference a steel S-N curve set up by a STEEL-S-N-
CURVE instruction. Comments similar to those for 'material' apply to 'sndata'. The
command is only of use for fatigue limit state checks and will be ignored in other cases.
The 'strands', 'diameter' and 'spacing' parameters define the number and size of strands and
the spacing of the prestress tendon. The diameter and spacing should be input in mm.
The 'prestress' parameter is the prestress load in an individual tendon (MN). The program
checks that this prestress is possible given the tendon size and material stress-strain curve.
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Concrete-Check – User Manual Command Formats
Command : PRINT-DATA
Syntax : PRINT-DATA
Applicable to : All checks
Example : PRINT-DATA
Description :
The PRINT-DATA command causes a summary of all current input data to be printed to the
current main output before any further instructions are interpreted. It is intended that PRINT-
DATA be used as required immediately prior to a DO-CHECKS instruction to force printing
of input data to be used in the check. The command is particularly useful in conjunction with
DATA-CHECK-ONLY but may be removed to reduce output levels in final production runs.
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Concrete-Check – User Manual Command Formats
Command : RATIO
Syntax : RATIO (ratio)
Applicable to : BS5400 serviceability limit state checks
Examples : RATIO
RATIO 0.5
Description :
The RATIO instruction permits the user to specify the ratio of live load moment (Mq) to
permanent load moment (Mg) for use in the evaluation of the tension stiffening effect for
crack width checks to BS5400. The use of this ratio is described in the Theory Manual.
The default value of 'ratio' is 0.0, signifying that there is no live load. This is also the value
assumed if the command is issued with no parameters.
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Concrete-Check – User Manual Command Formats
Command : REBAR-PROPERTIES
Syntax : REBAR-PROPERTIES material fy (code) (es (strn (f1)))
Applicable to : All checks
Examples : REBAR-PROPERTIES 10 410.0
REBAR-PROPERTIES 7 410.0 BS8110 210000.0
REBAR-PROPERTIES 5 410.0 BS5400 210000.0 0.0025
REBAR-PROPERTIES 6 410 DNV 200000.0 0.002 380.0
Description :
The REBAR-PROPERTIES command allows a table of material properties to be created for
reinforcing bars. Material properties can then be referenced by TOP-STEEL and BOTTOM-
STEEL commands via the REINFORCEMENT-BARS instruction.
The material parameter refers to the entry in this material table. Rebar entries may be added in
any order and may be overwritten by successive REBAR-PROPERTIES commands as
required. There is no facility to delete rebar materials, but they will not be used if they are not
referenced by REINFORCEMENT-BARS instructions. Up to ten rebar materials may be
created.
The rebar yield stress is specified by fy. This value should be specified in units of MNm-2.
The optional code parameter can take the values BS8110, BS5400, DNV, NS3473, MC78 or
S474, defining the type of stress-strain curve, as follows:
A. BS8110,MC78 (default) - bi-linear, type 1;
B. BS5400 - tri-linear, type 1;
C. DNV - tri-linear, type 2;
D. NS3473,S474 - bi-linear, type 2.
Full details of each stress-strain curve type are given in the CONCRETE Theory Manual.
Depending on which code is chosen, other parameters may also be specified, although all
parameters assume the default values from the relevant code if no value is specified. The
defaults are summarised in the following table:
code es (MNm-2) strn (MNm-2) fl (MNm-2)
BS8110 200000.0 N/A N/A
BS5400 200000.0 0.002 N/A
DNV 200000.0 0.002 0.8fy
NS3473 200000.0 N/A N/A
MC78 200000.0 N/A N/A
S474 200000.0 N/A N/A
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Concrete-Check – User Manual Command Formats
The f1 stress value enables the user to define the point at which the DNV stress-strain curve
changes from linear to parabolic. A default value is not explicitly embodied in the rules, so a
stress of 0.8fy is assumed by default, resulting in a curve similar to the BS5400 tri-linear
curve.
All the above codes define a compression curve, but this will be ignored if the
COMPRESSION-STEEL command has been used to define it as INEFFECTIVE.
The data does not contain any reference to material partial safety factors, which should be
entered by a separate MATERIAL-PARTIAL-SAFETY-FACTOR command. The yield
stress will then be reduced by the appropriate factor for the BS8110, BS5400, DNV and
MC78 curve types. Both the yield stress and the elastic modulus will be reduced for NS3473
and S474 curves. There is no restriction to the order in which REBAR-PROPERTIES and M-
P-S-F commands are input. The stored values will always reflect the latest entry of each type.
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Concrete-Check – User Manual Command Formats
Command : RECTANGULAR-AXES
Syntax : RECTANGULAR-AXES OFF
RECTANGULAR-AXES vectx vecty vectz
Applicable to : All checks
Examples : RECTANGULAR-AXES OFF
RECTANGULAR-AXES 1.0 0.0 0.0
Description :
The RECTANGULAR-AXES command is used with solid element models to specify
whether or not the stress axes used for the recovery of section forces follow the section being
defined, or conform to a fixed set of reference axes. The former option is the default (see
Section 4.10) and may also be achieved by RECTANGULAR-AXES OFF. The latter option
is selected by specifying a vector direction, which, when projected onto the surface being
defined, fixes the orientation of the X direction stresses and loads. The procedure for this is
as follows:
− loads per unit width are calculated at the location required in accordance with
Section 4.10. These loads are designated Nx, Ny, Nxy, Mx, My, Mxy, Nxy and Nyz.
They correspond to the location axes, X", Y" and Z";
− the reference vector given on the RECTANGULAR-AXES command is projected
into the plane of the slab at this location and forms the axis X"'. An error results if
the reference vector is parallel to Z", the through thickness axis;
− a right-handed cartesian system is defined using X"', Z"' and defining ZY"'. Z is
defined as being identical to Z";
− the load components are reorientated from X", Y", Z" to the new system (X'", Y"',
Z"') prior to use in subsequent code checks.
The above approach is most useful for sections that have been defined using cylindrical or
conic surfaces, yet where the reinforcement pattern is rectangular. Use of RECTANGULAR-
AXES allows the stresses to be converted ?? this reinforcement pattern prior to use. If this
were not done, reinforcement would have to be reorientated for each location checked
around the section.
This command is only of use when loads from an FE system are being used directly for code
checks. It has no action when previously enveloped loads are recovered or for stand alone
checks.
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Concrete-Check – User Manual Command Formats
Command : REDESIGN
Syntax : REDESIGN (OFF/mloop)
Applicable to : Ultimate strength checks
Examples : REDESIGN
REDESIGN OFF
REDESIGN 20
Description :
The REDESIGN command enables or disables the redesign facility for ultimate strength
checks.
The command may be used to switch redesign of reinforcement steel off (REDESIGN OFF)
or to turn it on (REDESIGN or REDESIGN 'mloop'). By default, redesign is disabled at
program start up.
The 'mloop' parameter is the maximum number of times that the program will progress
through the redesign loop before accepting that no solution may be found. Each loop
consists of resizing all rebar layers by an amount given by the 'resize' parameter in the TOP-
STEEL and BOTTOM-STEEL commands. Only those rebars with a non-zero 'resize'
parameter will be resized in this way on each loop. The default value of 'mloop' is ten.
The resizing process will only be performed at locations where the initial section fails the
ultimate strength check. There is no facility to resize steel sizes down, Resizing will
continue until the section becomes acceptable or 'mloop' is exceeded. On each redesign
loop, each rebar layer area will be resized thus:
Area' = Area * (1 + resize)
If redesign is successful in finding an acceptable size of steel, then subsequent checks,
including shear checks, will all use this redesigned steel area.
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Concrete-Check – User Manual Command Formats
Command : REDISTRIBUTION-MATRIX
Syntax : REDISTRIBUTION-MATRIX f11 f12 f13------fl8
f21 f22 f23------f28
f31 f32 f33------f38
. . . .
f81 f82 f83------f88
Applicable to : All limit state checks
Example REDISTRIBUTION-MATRIX 0.9 0.1 0.1 0.0 0.0 0.0 0.0 0.0
+ 0.1 0.9 0.1 0.0 0.0 0.0 0.0 0.0
+ 0.0 0.0 1.0 0.0 0.0 0.0 0.0 0.0
+ 0.0 0.0 0.0 1.0 0.0 0.0 0.0 0.0
+ 0.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0
+ 0.0 0.0 0.0 0.0 0.0 1.0 0.0 0.0
+ 0.0 0.0 0.0 0.0 0.0 0.0 2.0 0.0
+ 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.0
Description :
The REDISTRIBUTION-MATRIX command is used to premultiply all load envelopes and
load combinations in CONCRETE-CHECK immediately prior to their use in the code
checks.
The multiplication is of the form:
F' = M F
where: - F' is the modified load array to be used in the checks;
- M is the redistribution matrix;
- F is the input load array (NX, NY, NXY, MX, MY, MXY, NXZ, NYZ)
There is no reset for this command. It is turned off by specifying a unity matrix. The default
at program start up is also a unity matrix.
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Concrete-Check – User Manual Command Formats
Command : REINFORCEMENT-BARS
Syntax : REINFORCEMENT-BAR type mat sndata diameter
spacingl (spacing2) (finish)
Applicable to : All checks
Examples : REINFORCEMENT-BARS 6 2 0 25.0 180.0
REINFORCEMENT-BARS 2 9 1 32.0 32.0 200.0
REINFORCEMENT-BARS 12 6 0 20.0 150.0 HIBOND
Description :
The REINFORCEMENT-BARS command allows a table of reinforcement bar geometries
to be created for reference by TOP-STEEL and BOTTOM-STEEL instructions.
The 'type' parameter refers to the entry in the rebar geometry table. Rebar entries may be
added in any order and may be overwritten by successive REINFORCEMENT-BARS
commands as required. There is no facility to delete rebar geometries, but they will not be
used if they are not referenced by TOP-STEEL and BOTTOM-STEEL instructions. Up to
9999 rebar geometries may be created and used.
The 'mat' parameter refers to an entry in the rebar material property list created by a
REBAR-PROPERTIES command. It is not necessary that the REBARPROPERTIES
command should precede any REINFORCEMENT-BARS command, only that correctly
cross-referenced entries be current when a DO-CHECKS instruction is encountered,
The 'sndata' parameter may be used to reference a steel S-N curve set up by a STEEL-S-N-
CURVE instruction. Comments similar to those for 'material' apply to 'sndata'. The
command is only of use for fatigue limit state checks and will be ignored in other cases.
The 'diameter', 'spacingl' and 'spacing2' parameters define the size and centreline spacing of
the rebars. If 'spacing2' is zero or not given, then the rebars are assumed to be evenly spaced
at 'spacing 1' centres. If 'spacing2' is given, then the bars are assumed to be alternately
spaced at 'spacingl', 'spacing2', 'spacingl', etc. This enables bundled bars to be defined. If
given, 'spacingl' and 'spacing2' may not be less than the bar diameter. The diameter and
both spacings should be given in mm.
The 'finish' parameter is used to specify the surface finish of the reinforcement bar and may
be HIBOND, RIBBED, INDENT or PLAIN. This data is used in the CEB/FIP MC78 and
NS3473 crack width calculations. The default value is HIBOND.
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Concrete-Check – User Manual Command Formats
Command : RESET
Syntax : RESET
Applicable to : All checks
Example : RESET
Description :
The RESET command cancels all current reinforcement and prestress definitions set up by
means of TOP-STEEL and BOTTOM-STEEL instructions. It is intended that this command
be used after a DO-CHECKS instruction when the reinforcement/prestress is to be changed
for subsequent checks. Without this command, TOP-STEEL and BOTTOM-STEEL
commands are cumulative.
RESET does not cancel reinforcement/prestress geometry and materials set up by the
REINFORCEMENT-BARS, REBAR-PROPERTIES, PRESTRESS-TENDONS and
TENDON-PROPERTIES commands, Only the reference to these cards by TOP-STEEL and
BOTTOM-STEEL is cancelled. Subsequent steel definition may reference previously
created properties/materials quite freely.
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Concrete-Check – User Manual Command Formats
Command : SECTION
Syntax : SECTION numsec LIST ALL/loc1 (loc2 ----locn)
SECTION numsec (FULL)
SECTION numsec LIST valuel (value2---valuen)
Applicable to : All limit state checks
Examples : SECTION 5 LIST ALL
SECTION 6 LIST 3 5 7 9
SECTION 7
SECTION 31 LIST 5.0 10.0 15.0 20.0 25.0 30.0 35.0
+ 40.0 45.0 50.0 55,0 60.0
Description :
The SECTION command is currently only available for structures modelled using solid
elements. The CLEAR-SELECT, SELECT and PANEL commands should be used for shell
element models.
A 'section' is defined as the intersection between a 'surface' (defined on the SURFACE card)
and a set or group of elements (defined on the SET or GROUP cards). The SECTION
command assigns a number to this 'section' and optionally specifies locations along or
around the section at which checks are to be performed. Only one section may be defined in
the data for each DO-CHECKS. Successive definitions will overwrite the last, If more than
one section requires to be processed, each must be separated by DO-CHECKS instruction,
The SECTION command in CONCRETE-CHECK has two functions. If load data is to be
obtained directly from an FE analysis, then it is used in conjunction with the SURFACE,
SET/GROUP and optional DATUM and ORIGIN cards to define a section in the model
where load data is to be recovered. If load data is to be obtained from results stored by
CONCRETE-ENVELOPE, then the SECTION command alone is used to reference which
section is to be recovered, and which locations are to be recovered for it.
When obtaining results from CONCRETE-ENVELOPE the parameter 'numsec' identifies
the section to be recovered.
When accessing FE analysis results directly, the 'numsec' parameter is used to calculate the
position in the keyed filing system where check results are to be stored. If the storage of
check results is switched OFF then the 'numsec' parameter is simply used to aid
identification of the results in the output listing.
If the 'LIST' option is used when recovering results from an FE analysis, a list of unique
values is expected defining locations along/around the section. For CONE and CYLINDER
surface definitions, these values are angles in degrees relative to the base axes. For PLANE
surfaces, the values are distances in analysis units along the section.
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Concrete-Check – User Manual Command Formats
The 'LIST' option takes a different form when recovering results from CONCRETE-
ENVELOPE. It is followed either by 'ALL' (to recover all locations previously stored)
or by a list of the location numbers actually required.
Up to 100 locations may be identified or recovered by this command, which may
require a long list, therefore continuations are permitted when using the LIST option.
If the 'FULL' option, or no option, is used, then the program will recover a class
envelope (an envelope over all locations along/around the section). Refer to the
CONCRETE-ENVELOPE manual for more details of class envelopes.
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Concrete-Check – User Manual Command Formats
Command : SELECT
Syntax : SELECT class node1 (node2----)
Applicable to : All limit state checks
Examples : SELECT 1 0 11 12 13 14
Description :
This command allows the selection of nodes across a panel and therefore applies only to
concrete substructures modelled using thick and thin shell elements where stress results are
to be recovered directly from an FE analysis. Solid models should use the section definition
(4.10). The command may also be used in a stand-alone mode to identify output.
The SELECT command allows nodes to be selected by node number for checking when a
DO-CHECKS command is encountered. The first field is the class number for the following
nodes and should be an integer number from 1 to 3. Refer to the ANALYSE-NODE-
CLASSES command for details.
SELECT commands are cumulative. CLEAR-SELECT should be used to cancel previous
selections and start again. Refer to the CLEAR-SELECT command for more details.
Node selection is only cancelled when the program encounters a PANEL or SECTION
command.
A node number may be zero, signifying that a set envelope is to be recovered. This is only
valid when using the results of a previous CONCRETE-ENVELOPE run.
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Concrete-Check – User Manual Command Formats
Command : SERVICE-CHECK
Syntax : SERVICE-CHECK (OFF/ON)
SERVICE-CHECK (BS5400/BS8110/MC78/NS3473/S474)
(CITO14) (NS3473/MC78/CLARK)
Applicable to : Serviceability limit state checks
Example : SERVICE-CHECK OFF
SERVICE-CHECK
SERVICE-CHECK S474 NS3473
SERVICE-CHECK MC78 CITO14 NS3473
Description :
The SERVICE-CHECK instruction is used to specify that serviceability checks are to be
performed at subsequent DO-CHECKS instructions and to specify the type of check to
apply.
Available serviceability crack width checks are BS8110:Part 2, BS5400, the CEB/FIP Model
Code (MC78), CSA S474-94 or NS3473. SERVICE-CHECK ON initiates SLS checks using
the previously selected method (BS8110 is the initial default method). Tension stiffening
may be set on or off with a further command of that name. The SERVICE-CRITERIA
command allows the setting of limiting crack widths and stresses. Full details of the checks
provided may be found in the Theory Manual.
SERVICE-CHECK with no following data is equivalent to SERVICE-CHECK ON.
SERVICE-CHECK ON has the effect of switching on service checking with the last
specified method, or BS8110 if none have been specified. If no SERVICE-CHECK
instruction is given, serviceability checks will not be performed (the default is therefore
OFF).
When defining reinforcement for use in crack width evaluation to MC78, CSA S474 or
NS3473, certain rules must be observed if the program is to correctly select groups of
reinforcement. The methodology of the rebar selection procedure is detailed in the Theory
Manual.
The NS3473/MC78/CLARK flag is used to modify the method for calculating crack widths
when the crack direction is not perpendicular to the rebars. The following options are further
described in the Theory Manual.
− the NS3473 option causes crack spacing to be calculated as follows;
1
S=
Cos θ
∑ S i
i
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− the MC78 option considers each reinforcement group in turn and introduces a K3
term to allow for orientation, retaining the minimum spacing at cracks so
obtained.
− the CLARK option follows the nearest bar approach suggested by Clark.
NS3473 and MC78 are the default options for their respective codes. NS3473 is also the
default for CSA S474. The CLARK option is only valid for British Standards and is currently
the only valid option for these codes. Consequently, it is also the default for these checks.
The CITO14 flag optionally permits the calculation of crack widths using the Concrete-in-
the-Oceans Report No.14 approach. Again, refer to the Theory Manual for details. This
option is valid for MC78, CSA S474 and NS3473 checks.
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Concrete-Check – User Manual Command Formats
Command : SERVICE-CRITERIA
Syntax : SERVICE-CRITERIA width (rstress (cstress) )
Applicable to : Serviceability limit state checks
Examples : SERVICE-CRITERIA 0.2
SERVICE-CRITERIA 0.3 150.0
Description :
The SERVICE-CRITERIA command sets up data pertinent to the serviceability limit state of
cracking.
The following data may be created:
width - this is the allowable crack width in mm against which calculated
cracks are compared. If not given, width defaults to 0.1mm;
rstress - the maximum allowable reinforcement stress in MNm-2 for the
serviceability limit state of permanent damage. If not given, it
defaults to 140 MNm-2.
cstress - the maximum allowable concrete compressive stress in MNm-2 for
the serviceability limit state. If not specified the value defaults to 20
MNm-2.
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Concrete-Check – User Manual Command Formats
Command : SET
Syntax : SET set
Applicable to : All limit state checks
Examples : SET 31
Description :
The SET command is used to specify the FE analysis group or set number containing all
elements on which the checks are based. The GROUP instruction is identical to SET and
either may be used freely.
The GROUP or SET commands are needed if the checks require results from an FE
analysis, either directly or indirectly via a CONCRETE-ENVELOPE analysis. It is not used
if data is input directly to the data file.
When CONCRETE-CHECK takes loads directly from the FE analysis, the set specified
should contain all shell or solid elements needed to define the panel or section required to be
analysed. The command must be present even if a single node or location is to be processed.
When CONCRETE-CHECK recovers envelopes from CONCRETE-ENVELOPE, the set
number is important if it was used as part of the keyed filing system for storage of
envelopes.
Additionally, a set or group number of zero tells CONCRETE-CHECK to recover global
envelopes.
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Concrete-Check – User Manual Command Formats
Command : SHEAR-CHECKS
Syntax : SHEAR-CHECKS DNV/DEN/MC78/BS8110/BS5400/
NS3473/TRIAXIAL (options --- )
SHEAR-CHECKS (OFF/ON)
Applicable to : Ultimate Strength Checks
Examples : SHEAR-CHECKS BS8110 NOVCO NOLIMIT
SHEAR-CHECKS OFF
Description :
The SHEAR-CHECKS command controls whether shear checks are performed on the section
under ULS loads, and if so, what method and extent of checking is performed.
The 'method' parameter may be 'BS8110', 'BS5400', 'DNV', 'DEN' 'MC78', 'NS3473',
'TRIAXIAL', 'ON' or 'OFF'. The majority of these specify the method that will be used for
shear capacity checks. Included are two British Standards, Det norske Veritas Rules,
Department of Energy Guidance, the CEB/FIP Model Code MC78 and Norwegian Standards.
TRIAXIAL specifies that checks are to be performed using a detailed evaluation of stress and
strain at the mid plane of the section, based on methodology by Collins et al. The TRIAXIAL
option is only available when the layered method is being used to solve the section (see the
METHOD command).
The 'ON' and 'OFF' parameters switch shear checks on or off, as required. SHEAR-CHECKS
ON re-enables the last selected method, if previously turned off. The default code at program
start up is 'BS8110' with no options.
Full details of the checks performed when any of these options are selected may be found in
the Theory Manual.
The following shear check options are available:
'NOLIMIT' - the numerical limits on shear stress (5.0 Nmm-2 in BS8110, 4.75
Nmm2 in BS5400 assuming γ=1.25) are not applied, only the variable
limit (0.8 √ fcu or 0.75 √ fcu);
'NOVCO' - in BS8110 checks, the shear capacity for a cracked, prestressed
section is not limited to Vco, as suggested by 4.3.8.3 (b);
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'TENSION' - specifies that shear capacity should be calculated even for sections
fully in tension (both extreme fibres). This option is not yet
implemented;
'EXVCO' - expands the calculation of Vco. in BS8110 and BS5400 to include the
effects of axial loading and prestress;
'NORMAL' - includes the effect of normal load on shear capacity. This is set by
default in BS8110 but is optional for BS5400;
'STRICTM0' - calculate the Mo/M term directly in accordance with empirical code
equations (therefore not applicable to the TRIAXIAL option), by
including prestress moment in the derivation of M0, rather than as part
of the applied moment M;
'ADDTEND' - specifies that any prestress tendons are to be included in the
calculation of steel area (As) and effective depth (d) in DNV, NS3473
and MC78 checks. The default for these checks is to consider
reinforcement steel only. Other rules always include tendons in
appropriate checks;
'INCLUDEP'- in DNV checks, optionally adds the prestressing force (Pfd) to the axial
load (Nfd) for the calculation of the limiting value of Vcr+ Vpr. The
default is the strict code interpretation. Pfd is factored by its load
partial safety factor prior to inclusion in Nfd. In NS3473, when this
options is switched on, prestress is included with axial load in all
shear calculations, even though this is not strictly stated in the rules;
'USEPEQ' - in BS8110 and BS5400 code checks, use formulae for prestress load
on section rather than axial load for the calculation of shear capacity
in the presence of normal load, N, on the section;
'NOAXIAL' - base calculation of effective tensile steel area on section properties
evaluated for moment loads (applied plus prestress) only, not the axial
components of these loads;
-
'LIMITM0' in NS3473, limit the calculated value of Mo by restricting the axial
load to a compression of 0.4hfcn/γc;
'OVER40' - in BS8110 and BS5400 code checks, this option permits shear
capacity to be evaluated without fcu being restricted to 40 Nmm-2 in
the calculation of Vc;
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Concrete-Check – User Manual Command Formats
'AVERAGE' - in TRIAXIAL checks, use average of water pressures on opposing
faces as the through-thickness loading;
'MAXIMUM' - in TRIAXIAL checks, use the maximum water pressure from
opposing faces as the through-thickness loading;
'MINIMUM' - in TRIAXIAL checks, use the minimum water pressure from
opposing faces as the through-thickness loading;
'NONE' - in TRIAXIAL checks, ignore the effect of water pressures from either
opposing face on through-thickness stresses (negates AVERAGE,
MAXIMUM or MINIMUM).
The following table summarises which options are available for each different type of shear
check:
Method Available Options
DNV STRICTM0, ADDTEND, INCLUDEP, NOAXIAL
DEN N/A
MC78 N/A
BS8110 NOLIMIT, NOVCO, EXVCO, STRICTM0,
USEPEQ, NOAXIAL, OVER40
BS5400 NOLIMIT, EXVCO, NORMAL, STRICTM0,
USEPEQ, NOAXIAL, OVER40
NS3473 STRICTM0, ADDTEND, INCLUDEP, NOAXIAL,
LIMITM0
TRIAXIAL AVERAGE, MAXIMUM, MINIMUM, NONE
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Concrete-Check – User Manual Command Formats
Command : SHEAR-REINFORCEMENT
Syntax : SHEAR-REINFORCEMENT (diam material xspacing yspacing)
Applicable to : Ultimate Strength checks
Example : SHEAR-REINFORCEMENT 12.0 6 200.0 250.0
SHEAR-REINFORCEMENT
Description :
The SHEAR-REINFORCEMENT command allows the definition of shear steel for ultimate
strength shear resistance checks. The program will determine the required shear steel for
each load condition considered and compare it with the amount specified on this card,
showing a section failure if inadequate steel is provided.
The parameters on the instruction line are self explanatory. The diameter and spacings
should be given in mm. Bars of given diameter are spaced in each of the X and Y slab axes
as indicated. Refer to Section 4.10 for a description of the slab axes. The 'material' item
references a reinforcement bar material property set up by a REBAR-PROPERTIES
command.
SHEAR-REINFORCEMENT with no parameters will turn off any previously defined shear
steel. This is the default at program start up.
If no SHEAR-REINFORCEMENT command is issued, or shear steel is turned off, then the
program will use the yield stress from the first reinforcement material (created by default or
by REBAR-PROPERTIRS 1---) to determine the area of links required by the shear checks,
if any.
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Concrete-Check – User Manual Command Formats
Command : SIGNS
Syntax : SIGNS factnx factny factnxy ---- factnxz factnyz
Examples : SIGNS -1.0 -1.0 1.0 -1.0 -1.0 1.0 1.0 1.0
Description :
The SIGNS command may be used to change the sign of selected load components obtained
from the FE system whether they have been produced by CONCRETE-ENVELOPE or
extracted directly from the FE model. The command is intended to allow the user to change
from an FE analysis specific sign convention to the CONCRETE suite convention where
these differ. Refer to the appropriate appendix to see if this is necessary.
The SIGNS command can also be used to alter the sign convention and/or scaling of
DIRECT/MAXIMUM/MINIMUM input of envelope, prestress, deformational and post-
deformational loading.
By default, at program start-up, the eight factors (for NX, NY, NXY, MX, MY, MXY, NXZ and
NYZ) loads are all unity. CONCRETE-CHECK uses the factors to multiply the load
components prior to use. It is possible to factor the loads by non unit values as well as by
changing signs, if this is so required.
The CONCRETE-CHECK sign convention for loads is given in Section 4.3.
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Concrete-Check – User Manual Command Formats
Command : STATIC-COMBINATION
Syntax : STATIC-COMBINATION DIRECT nx ny nxy nyz
STATIC-COMBINATION ANALYSIS data STATIC-
COMBINATION NONE
Applicable to : Fatigue checks
Examples : STATIC-COMBINATION DIRECT 100.0 2000.0 300.0
+ 500.0 1000.0 200.0 200.0 400,0
STATIC COMBINATION ANALYSIS 12
Description :
The STATIC-COMBINATION command specifies the loading to be used as a constant static
loading for all fatigue load conditions.
By default, at program start up, no static combination is considered. STATIC-
COMBINATION NONE with no other arguments returns to this state.
A keyword of DIRECT specifies that the static loads are to be read from this input line (and
any continuation lines). Eight components of load (NX to NYZ) should be given. Direct loads
(NX, NY, NXY, Nxz, NYZ) should be specified in units of MN per metre width. Moments (MX,
MY, MXY) should be given in MNm per metre width.
The ANALYSIS keyword signifies that stresses are to be recovered directly from the backing
files for an FE analysis. A SUPER-ELEMENT command and some form of location selection
(SECTION, PANEL, SELECT) must be present in the data for this command to execute
properly. The data on this line is dependent on the FE system in use, refer to the appropriate
appendix.
The static combination defined here should reference all truly static loads such as dead load
and operating weights carried by the structure during all wave conditions. Static offsets that
vary with wave condition, such as current effects, are entered on the FATIGUE-CYCLE
commands.
Static conditions are required for concrete fatigue as the material endurance limit depends on
the acting stresses, not just a stress range.
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Concrete-Check – User Manual Command Formats
Command : STEEL-S-N-CURVE
Syntax : STEEL-S-N-CURVE sndata stressl cycles1 slope1 ----
Applicable to : Fatigue checks
Example : STEEL-S-N-CURVE 3 300.0 2E6 3.0 200.0 2E7 1.7
+ 50.0 1E9 3.0
Description :
The STEEL-S-N-CURVE command may be used to create S-N curves for reinforcement
steel bars and prestress tendons.
Up to ten steel S-N curves may be created in this way and may be referenced by the
PRESTRESS-TENDONS and REINFORCEMENT-BARS commands in the same way that
material properties are referenced. For fatigue checks, when a DO-CHECKS instruction is
encountered, each referenced 'sndata' curve must have been defined on a STEEL-S-N-
CURVE command.
The remainder of the parameters on the STEEL-S-N-CURVE command permit a multi-
linear S-N curve to be defined containing up to ten linear segments when plotted on log-log
axes. For each segment, the following is required:
stress n - the stress at a point on the line segment
cycles n - the corresponding number of cycles
slope n - the positive inverse logS/logN slope
For the first line segment, any stress on the line may be used. For subsequent segments, the
stress should be at the intersection with the previous segment.
By default, on program start up, the first curve type (sndata = 1) is a trilinear curve defined
as follows:
Segment 1 2 3
stress n 400.0 235.0 65.0
cycles n 10177.5 251773.5 8831122.1
slope n 6.0 2.8 4.8
Continuation lines may be used to specify data that exceeds the available space on just one
line.
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Concrete-Check – User Manual Command Formats
Command : STOP
Syntax : STOP
Applicable to : All checks
Example : STOP
Description
The STOP command is synonymous with END and immediately terminates the current run.
Any further commands in the data file are ignored, all files are closed and control is
returned to the operating system.
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Concrete-Check – User Manual Command Formats
Command : STRENGTH-CHECK
Syntax : STRENGTH-CHECK (OFF/ON)
Applicable to : Ultimate strength checks
Example : STRENGTH-CHECK
STRENGTH-CHECK OFF
Description
The STRENGTH-CHECK instruction is used to specify that ultimate strength checks are to
be performed at subsequent DO-CHECKS instructions until overridden by a STRENGTH-
CHECK OFF instruction.
STRENGTH-CHECK with no following data is equivalent to STRENGTH-CHECK ON.
If no STRENGTH-CHECK instruction is used, ultimate strength checks will not be
performed.
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Concrete-Check – User Manual Command Formats
Command : STRENGTH-CRITERIA
Syntax : STRENGTH-CRITERIA ( maxrs ( maxts ))
Applicable to : Strength checks only
Example : STRENGTH-CRITERIA
STRENGTH-CRITERIA 0.001
Description
The STRENGTH-CRITERIA instruction is used to specify the maximum permissible rebar
and tendon layer strains for ultimate limit state (strength) checks.
The maxrs value is taken as the maximum strain in the rebar layer. If this value is omitted,
it defaults to the maximum elastic strain in each rebar layer with due allowance for material
partial safety factors and possible bi-linear stress strain curves.
The maxts value is taken as the maximum strain in the tendon layer. If this value is
omitted, it defaults to the maximum elastic strain in each tendon layer, as for rebars.
Strength criteria can be reset to the default by specifying this command with no parameters.
If given, the maxrs and maxts values apply to ALL rebar or tendon layers.
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Concrete-Check – User Manual Command Formats
Command : STRESS-AXES
Syntax : STRESS-AXES (dx dy dz (x y z))
Applicable to : ALL checks
Examples : STRESS-AXES
STRESS-AXES 1.0 -1.0 2.3
STRESS-AXES 0.0 1.0 0.0 100.0 200.0 -5.0
Description :
The STRESS-AXES command is used to force CONCRETE-CHECK to perform nodal
stress averaging from elemental stress results from the ASAS finite element system, prior to
using these stresses to derive section forces for stress checks. This command is currently
not available when CONCRETE is used as a post-processor to SESAM.
The default at program start-up is for no averaging to be performed. CONCRETE-CHECK
will expect to find nodally averaged stresses on backing file (produced by ASASPOST).
Once a STRESS-AXES command has been issued, the program will no longer search for
averaged stresses, but will revert to looking for element stress results, which it will nodally
average, and then use in exactly the same way as averaged stresses recovered from file.
Nodal averaging cannot be turned off. Once specified, subsequent STRESS-AXES
commands can only be used to redefine the reference direction and reference point,
The STRESS-AXES command with no parameters is used to force averaging of solid
element stresses. These will be converted to the global axis system prior to averaging at a
node.
The reference direction (defined by components dx, dy and dz) and reference point (defined
by co-ordinates x, y and z) are used for averaging shell element stresses. If not given,
reference point co-ordinates at the origin (0, 0, 0) are assumed. The reference direction and
reference point are used as follows:
− a Cartesian axes system is used to specify directional stresses on general flat or
curved structures, including hoop and longitudinal stresses in straight cylinders. These
are defined in terms of a reference direction and a reference point. Firstly, the top and
bottom surfaces of the shell are defined. This is done by drawing a vector from the
reference point towards the node in question. This is called the control vector. The
first surface cut by the control vector is defined as the bottom surface, and the second
as the top surface. The new Z-axis at this node is normal to the shell and positive in
the direction from the bottom surface towards the top surface;
− the new X-axis lies in the plane containing the new Z-axis and the reference direction:
note that the reference direction is specified by direction cosines with respect to the
global axis system. The X-axis is positive on the side of the Z-axis containing the
positive reference direction. The new Y-axis forms a right-handed set with the new X-
and Z-axes;
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− the above rules break down in two cases. The first is where the control vector and the
reference direction are parallel and the second is where the control vector is tangential
to the shell surface. In both cases, warnings are printed when the control vector is
within 5° of the shell surface tangent. Errors are printed should the angle be less than
1°. In the case of an error, the node in question is omitted from the checks.
Stresses for all elements in the given group present at the node being checked are converted
to the above axis system prior to averaging and use in the code checks.
The STRESS-AXES command is currently implemented only for the ASAS finite element
system. Other FE programs should average the stresses prior to analysis using
CONCRETE-CHECK.
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Concrete-Check – User Manual Command Formats
Command : STRESS-INTEGRATION
Syntax : STRESS-INTEGRATION option
Applicable to : All checks
Example : STRESS-INTEGRATION SIMPLE
Description
This instruction allows the accuracy of stress extraction from a solid element FE model to be
set. The following options are available:
ACCURATE - stresses are extracted at every intersection between an element
face and the location being specified. This includes internal faces
of higher order elements.
MODERATE - stress are only extracted at intersections with
external element faces.
SIMPLE - stresses are only extracted at the top and bottom surfaces of the
slab, where these intersect the required location.
Section forces (NX, NY, NXY, MX, MY, MXY, NXZ, NYZ) are then evaluated by integrating
these stresses across the depth of the section, as described in the Theory Manual. The
accuracy of this integration depends on the option chosen.
The default accuracy is ACCURATE. This provides the most detailed stress integration and,
in general, should be used in all cases where stress are expected in all directions.
A stress accuracy of MODERATE is intended to be used where the slab is represented by
many higher order elements across its depth. The extra computation involved in calculating
mid-face stresses is unnecessary in this case. Note that there is no difference between
ACCURATE and MODERATE for lower order elements.
The SIMPLE option is useful in reducing computation time by considering only surface
stresses. This option should only be used where the stress distribution across the section is
known to be close to linear. Note that out-of-plane shear is rarely linear (probably parabolic)
so this option should be avoided where there is significant out-of-plane load.
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Concrete-Check – User Manual Command Formats
Command : SUBROUTINE-TRACE
Syntax : SUBROUTINE-TRACE (ON/OFF)
Applicable to : All checks
Examples : SUBROUTINE-TRACE
SUBROUTINE-TRACE OFF
Description :
Like the DEBUG command, SUBROUTINE-TRACE may be used to monitor progress
through the program and is intended only for users with a knowledge of the internal
operations of CONCRETE-CHECK. The list of subroutine entries and exits produced is
extremely lengthy, so this command should be used with care.
SUBROUTINE-TRACE with no parameters is taken as SUBROUTINE-TRACE ON.
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Concrete-Check – User Manual Command Formats
Command : SUMMARISE
Syntax : SUMMARISE
Applicable to : All checks
Example : SUMMARISE
Description
The SUMMARISE instruction causes CONCRETE-CHECK to print maximum code checks
obtained for each concrete face, rebar layer, etc to the summary file. The instruction also
causes such maxima to be reinitialised (as at the beginning of the data), so that the next
SUMMARISE command only refers to checks performed since the last such command.
Separate maxima are maintained for ULS, SLS and FLS checks and each will be printed
when a SUMMARISE is requested as long as there have been checks of the appropriate type
performed since the last SUMMARISE instruction (or the beginning of run).
Issuing a SUMMARISE command before the first DO-CHECKS instruction has no effect.
Maximum values are always printed after the last results check, irrespective of whether there
is a SUMMARISE command in the data or not.
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Concrete-Check – User Manual Command Formats
Command : SUPER-ELEMENT
Syntax : SUPER-ELEMENT data --
Applicable to : All limit state checks
Examples : SUPER-ELEMENT CA00 T113
Description :
The SUPER-ELEMENT instruction allows the user to specify the FE analysis model that is
to be used for the recovery of geometry and loads in subsequent limit state checks.
The data specified on the instruction line is very much dependent on the actual FE system in
use. The user should refer to the appendix appropriate to this system for details.
Some FE systems allow multiple SUPER-ELEMENT entries in one data file, so that the
model for which stresses are recovered can be changed. Once again, reference should be
made to the appropriate appendix.
A valid SUPER-ELEMENT instruction must be present in the data if limit state loads are to
be recovered directly from an FE system, or recovered from CONCRETE-ENVELOPE.
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Concrete-Check – User Manual Command Formats
Command : SURFACE
Syntax : SURFACE PLANE normalx normaly norrmalz
SURFACE CYLINDER axisx axisy axisz radius
SURFACE CONE axisx axisy axisz angle
Applicable to : All limit state checks
Examples : SURFACE PLANE 0.0 0.0 1.0
SURFACE CYLINDER 0.0 1.0 0.0 1.500
SURFACE CONE 0.0 0.0 1.0 12.25
Description :
The SURFACE command is currently only required for structures modelled using solid
elements where stress results are to be obtained directly from an FE analysis. Models
using shell elements should use other means of location selection, such as PANEL and
SELECT.
Load components for solid models are evaluated at specific locations around or along
structural sections. Sections are defined as the intersection of a defined surface with a
given subset of elements. When a DO-CHECKS instruction is encountered and a
SECTION command is current, the latest SURFACE, ORIGIN, DATUM and SET or
GROUP commands are used to define locations around the section for use in stress
recovery.
The creation of sections is described in Section 4.10 and under the SECTION
command. The definition of the surface used to create each section is provided by this
command and optionally by the ORIGIN and DATUM commands,
Three types of surface may be defined as below:
PLANE - a general flat plane. This plane is defined by specifying a
vector which is normal to the required plane;
CYLINDER - a cylindrical surface defined by a centroidal axis vector
and a radius (input in the units of the analysis);
CONE - a conic surface defined by an axis of revolution and an
angle in degrees between this axis and the conic surface.
The surface normal for PLANEs and the axes for CYLINDERS and CONEs are
defined as vectors using projections onto the structure (or super-element) global X, Y
and Z axes. For example, the vector (0.0 1.0 0.0) defines a vector in the global Y
direction, Together with an origin defined on an ORIGIN command (or defaulting to
0.0 0.0 0.0), the surfaces are then fully defined in three dimensions.
Apart from the ORIGIN command mentioned above, the other optional command
relating to surface definition is the DATUM instruction, which specifies a datum
relative to which locations along or around the section may be defined. The user should
refer to this command description for more details.
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Concrete-Check – User Manual Command Formats
Command : SYMBOL-VALUE
Syntax : SYMBOL-VALUE symbol value
Applicable to : All checks
Examples : SYMBOL-VALUE KEY1 23
Description :
The SYMBOL-VALUE command is used to allocate or reallocate values to symbols set up
by NEW-SYMBOL and used by KEY-FIELDS to define part or all of the keyed filing
system. The value assigned to a symbol should be within the range specified for that field
via the KEY-RANGES instruction,
The following reserved symbols are automatically updated by the program and should not
be assigned values by SYMBOL-VALUE:
NODE, LOCATION, GROUP, SET, CLASS, SECTION, ENVELOPE
Section 4.9 gives a full description of the CONCRETE keyed filing system.
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Concrete-Check – User Manual Command Formats
Command : TENDON-PROPERTIES
Syntax : TENDON-PROPERTIES material fpu et (cs (ec fyc) )
(ALTERNATE)
Applicable to : All checks
Examples : TENDON-PROPERTIES 3 410.0 200000.0
TENDON-PROPERTIES 2 650.0 165000.0 0.0 ALTERNATE
Description
The TENDON-PROPERTIES command allows a table of material properties to be created
for prestress tendons. Material properties can then be referenced by TOP-STEEL and
BOTTOM-STEEL commands via the PRESTRESS-TENDON instruction.
The 'material' parameter refers to the entry in this material table. Tendon entries may be
added in any order and may be overwritten by successive TENDON-PROPERTIES
commands as required. There is no facility to delete tendon materials, but they will not be
used if they are not referenced by PRESTRESS-TENDON instructions. Up to ten tendon
materials may be created.
The remaining items on the line define the stress-strain curve for the tendon material being
created.
In tension, a trilinear curve based on that shown in BS8110: Part 1: Figure 2.3 is defined. The
characteristic strength of prestressing tendons 'fpu' and the tensile modulus 'et' must be
specified (in MNm-2). If the critical strain 'cs' is not specified, it defaults to the value 0.005.
Setting 'cs' to zero reduces the curve to bi-linear.
A compressive bi-linear curve may also be defined using the compressive modulus, 'ec' and
the compressive yield stress, 'fyc' in MNm-2. This facility is included for generality only and
by default, no compressive capability is assumed for the prestress.
The material strengths given here do not contain any reference to material partial safety
factors. These should be entered on a separate MATERIAL-PARTIAL-SAFETY-FACTOR
command. Specification of mpsfs will automatically adjust the tendon stress-strain curves.
There is no restriction on the order of TENDON-PROPERTIES and M-P-S-F commands.
The most current will be in effect when DO-CHECKS is encountered.
The ALTERNATE parameter, if given, reduces the entire stress-strain curve (not just the
maximum stresses) by dividing by the material partial safety factor for prestressing. This
capability allows the use of codes such as CSA 5474 and NS3473. Refer to the Theory
Manual for more details.
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Concrete-Check – User Manual Command Formats
Command : TENSION-STIFFENING
Syntax : TENSION-STIFFENING (ON/OFF/LIMITED)
Applicable to : Serviceability Limit State Checks
Example : TENSION-STIFFENING
TENSION-STIFFENING OFF
Description :
The TENSION-STIFFENING command is used to control whether the extreme fibre strain,
used in the evaluation of serviceability crack widths, is reduced by the effect of tension
stiffening.
The default at program start-up is ON. TENSION-STIFFENING with no parameters is
equivalent to TENSION-STIFFENING ON. The LIMITED option also turns tension
stiffening on (if not already), but modifies the calculation of strains as well when using
BS8110 equations. Refer to the Theory Manual for more details. These alternative
calculations are disabled again by a further issue of this command without the LIMITED
option.
Note that tension stiffening is permitted for crack width calculations to BS8110 and most
other codes, but is not allowed for checking to Department of Energy Guidelines.
Tension stiffening calculations are never performed by the program when tensile behaviour
of concrete has been defined via the CONCRETE-PROPERTIES TENSION or
CONCRETE-PROPERTIES DEFINED commands, irrespective of the setting of TENSION-
STIFFENING. It is assumed that the user specified tensile properties make provision for the
action of concrete between cracks.
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Concrete-Check – User Manual Command Formats
Command : TITLE
Syntax : TITLE title
Applicable to : All checks
Example : TITLE CORMORANT ALPHA : COLUMN Cl
Description :
The TITLE instruction is used to specify a title which will be included in the heading of
each page of tabular output. The title may be up to eighty characters long, including
embedded blanks. It may be changed several times during the run, if so required.
If no TITLE instruction is used, a blank title line will be printed.
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Concrete-Check – User Manual Command Formats
Command : TOP-STEEL
Syntax : TOP-STEEL REBARS/TENDONS type cover angle (resize)
Applicable to : All checks
Examples : TOP-STEEL TENDONS 3 100.0 0.0
TOP-STEEL REBARS 6 30.0 90.0 0.05
Description
The TOP-STEEL command allows the definition of reinforcement layers and tendon layers
relative to the top face of the concrete slab being checked. The command is similar to
BOTTOM-STEEL, which allows definition relative to the bottom face.
The top face of the slab is defined as the face with the larger slab normal (Z") coordinate.
Refer to Section 4.3 for details of the slab axis system.
Both reinforcement steel (REBARS) and prestress tendons (TENDONS) can be defined with
this command. The following additional data is required:
- type an integer referencing a REINFORCEMENT-BARS or PRESTRESS-
TENDONS card with details of the diameter, spacing, material, etc. for the
steel. The appropriate type integer must have been set up when a DO-
CHECKS instruction is encountered;
- cover, the steel cover in millimetres. For rebars, this is the cover from the top face
to the closest point of the steel bars. For tendons, this is the distance from
the top face to the tendon centre line;
- angle, the orientation in degrees of the steel in the plane of the slab, relative to the
slab X axis. Refer to Section 4.3 for details of the slab axes;
- resize, for ultimate limit state checks, the resize rate per iteration. This item is only
valid for REBARS, and defaults to zero if not given. During ultimate limit
state checks, CONCRETE-CHECK will automatically resize any rebar
layers with a non-zero 'resize' rate. Refer to the REDESIGN command for
more information.
Rebars and tendons may be created by successive BOTTOM-STEEL and TOP-STEEL
cards. Up to sixteen layers of rebars and ten layers of tendons are allowed. These layers may
be defined at the same or different depths entirely at the discretion of the user. When a
reinforcement/ prestress arrangement must be changed, the RESET command should be used
to cancel all previous definitions.
There is no restriction that steel should be closer to the top face for the TOP-STEEL
command to be used. All steel may be created by either the TOP-STEEL or BOTTOM-
STEEL commands. The only restriction is that the final steel lies within the section. Note,
however, that the TOP-STEEL command cannot be used to
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Concrete-Check – User Manual Command Formats
specify the position of the steel in the slab until the CONCRETE-DEPTH is specified. If
TOP-STEEL is to be used, a CONCRETE-DEPTH command must be present in the data. It
is possible to run CONCRETE-CHECK using slab depths extracted from an FE analysis; in
this case, BOTTOM-STEEL should be used throughout.
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Concrete-Check – User Manual Command Formats
Command : UNITS
Syntax : UNITS faclen facfor
Applicable to : All limit state checks
Examples : UNITS 1000.0 1.0
Description
The purpose of the UNITS command is to specify the multiplication factors to convert from
the units of the FE analysis to those of the CONCRETE-CHECK program.
The UNITS command can also be used to alter the sign convention and/or scaling of
DIRECT/MAXIMUM/MINIMUM input of envelope, prestress, deformational and post-
deformational loading.
CONCRETE-CHECK assumes the following units:
− length in millimetres;
− force in newtons.
If the analysis units are different from the above, the UNITS command may be used to
specify 'faclen' and 'facfor' to factor lengths and forces from the analysis prior to enveloping
and storage.
If no UNITS command is given, length and force factors of unity will be assumed. If non-
zero values are given, the loads and dimensions from the analysis will be multiplied by these
factors prior to use in the various checks.
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Concrete-Check – User Manual Command Formats
Command : WATER-PRESSURE-IN-CRACKS
Syntax : WATER-PRESSURE-IN-CRACKS ptop (pbot) (method)
WATER-PRESSURE-IN-CRACKS OFF
Applicable to : All limit states
Examples : WATER-PRESSURE-IN-CRACKS OFF
WATER-PRESSURE-IN-CRACKS 2.511
WATER-PRESSURE-IN-CRACKS 0.0 1.50 BASIC
Description
This command is used to specify the values of water pressure considered to be present in any
cracks found in the structure, or to switch off this effect. The default at program start up is
for no water pressure to be considered in cracks.
Different external fluid pressure can be specified for top and bottom faces of the slab using
the parameters ptop and pbot. If only one value is specified it is assumed to apply to both
faces. A pressure of zero is used to indicate that there is no fluid on a particular face. The
external pressure should be specified in units of Nmm-2.
WATER-PRESSURE-IN-CRACKS simulates the additional pressure acting on the open
faces of the cracks, which tends to open the cracks further and increases tensile strains in the
reinforcement. The way in which water pressure is used in the various checks is described in
appropriate sections of the Theory Manual.
For the layered METHOD, rather than add water pressure to external loads acting on the
section (and adjust it to reflect varying crack depths), the effect is simulated by modifying
the stress-strain curve for cracked concrete to include the additional compression caused by
the water. This modification to the stress-strain curve is governed by the method parameter
as follows:
EXACT This is the default. Cracked concrete (beyond zero strain or the cracking
strain, if the latter is defined by appropriate CONCRETE-PROPERTIES
data) is assumed to be at a compressive stress equal to the water pressure. If
the 5474 option for CONCRETE-PROPERTIES TENSION is active,
allowance is made for stress transfer by bond into the concrete between
cracks. EXACT will produce a sudden change in stress at the cracking
strain, and can lead to poor convergence.
BASIC A simplified stress strain curve is defined whereby no stresses are
permitted that are more tensile than the water pressure, irrespective of
strain. This smoothed curve generally improves convergence.
EXTENDED As for EXACT, but the effect of bond transfer in accordance with S474 is
increased by an enhancement factor. See the Theory Manual for a detailed
explanation.
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Concrete-Check – User Manual Command Formats
Command : WATERTIGHTNESS
Syntax : WATERTIGHTNESS (DNV) dpres
WATERTIGHTNESS S474 (stress)
WATERTIGHTNESS OFF / NS3473
Applicable to : SLS Checks
Examples : WATERTIGHTNESS OFF
WATERTIGHTNESS 0.1
Description :
This command is used to specify whether or not watertightness checks are to be performed
and to what code of practice. If a valid code is specified or a non-zero differential pressure
given, the section will be assessed for watertightness, as part of the serviceability checks (see
Theory Manual for more details).
Watertightness checks to DnV rules require the differential pressure to be specified. The
code name in this special instance is optional. The default differential pressure at startup is
zero, and this state can be reinstated later by a WATERTIGHTNESS DNV 0.0,
WATERTIGHTNESS 0.0 or WATERTIGHTNESS OFF instruction. The differential
pressure should be specified in units of Nmm-2.
When WATERTIGHTNESS S474 is selected, watertightness is evaluated using the criteria
specified in Canadian Standards Association 5474 - 94: Section 9.5.1. By default, the
limiting tensile stress used in watertightness calculations to CSA S474 is 0.25ftmax, where
ftmax is given on the CONCRETE-PROPERTIES TENSION command. If ftmax is not so
specified, then 0.4λ√/fc' is used instead, where λ depends on the specified CONCRETE-
DENSITY and fc’ is the cylinder strength for whichever concrete properties are current. Both
of these defaults can be overwritten if a value of stress is specified on the
WATERTIGHTNESS command. The value of stress may be zero.
Watertightness checks to NS3473 are in accordance with Table A.8 of the 4th edition and are
for Class b) structures.
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Concrete-Check – User Manual Command Formats
Command : WRITE
Syntax : WRITE (ON/OFF)
Applicable to : All limit state checks
Examples : WRITE
WRITE OFF
Description :
The WRITE command controls the writing of unity check results to backing file for
subsequent access by CONCRETE-PLOT. The precise information written to file depends
on the limit state checks being performed and may include the following:
General - concrete thickness
ULS Checks - concrete utilisation (top/bottom)
corresponding critical angles (top/bottom)
rebar redesign loops and utilisations
tendon utilisations
shear utilisation
shear steel areas
SLS Checks - crack widths (top/bottom)
corresponding angles (top/bottom) rebar
utilisation
concrete utilisation
FLS Checks - concrete lives (top/bottom)
corresponding critical angles (top/bottom)
rebar lives
tendon lives
Full details of the code check results that are available for plotting may be found in the
CONCRETE-PLOT User Manual.
The default at program start-up is not to write results to file. Thus, a WRITE ON command
must be present in the data if CONCRETE-PLOT is to be used with code check results.
WRITE with no parameters is equivalent to WRITE ON.
One record is written to file for every node (shell element models) and location (solid
element models) for which code check results are produced. The key number used for this
record is in accordance with the KEY-FIELDS and KEY-RANGES commands. If other limit
state checks have already been stored for this node/location, these are recovered prior to
rewriting the record. Results for limit state checks in the current run will overwrite any
previous results.
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Concrete-Check – User Manual Summary of Commands
Appendix - A Summary of Commands
A.1 INTRODUCTION
The following is a summary of the commands available within CONCRETE-CHECK. Items
in upper case are keywords, those in lower case are text/numerical values required by the
program. Brackets indicate optional values, whilst slashes ('/') represent optional data. Lists
of data are indicated thus (----). Section 5.0 includes a full description of these instructions.
A.2 RUN CONTROL COMMANDS
ANALYSE-NODE-CLASSES class1 (class2 (class3 (class4)))
BEGIN-PLOT
CHANGE-INPUT-STREAM (stream (file))
CODE-CHECK (ON/OFF)
DATA-CHECK-ONLY
DEBUG OFF/(level routine (values ----))
DO-CHECKS ECHO
(ON/OFF) END
FINISH-PLOT
INTERACTIVE
LIST-INPUT-DATA (ON/OFF)
MAXIMUM-ERRORS maxerr
OUTPUT-LEVEL SUMMARY/BRIEF/INTERMEDIATE/DETAILED (BRIEF/FULL)
PRINT-DATA STOP
SUBROUTINE-TRACE (ON/OFF)
SUMMARISE
SUPER-ELEMENT data --
TITLE title
WRITE (ON/OFF)
A.3 NODE, SET AND LOCATION SELECTION
CLEAR-SELECT class node1 (node2 ----)
DATUM vectorx vectory vectorz
GROUP set
ORIGIN x y z
PANEL SAMPLE/SWEEP (angtol)
RECTANGULAR-AXES OFF/vectx (vecty vectz)
SECTION numsec (FULL)/(LIST valuel (value2 ----))
SECTION numsec LIST ALL/loc1 (loc2---)
SELECT class nodel (node2 ----)
SET set
STRESS-AXES (dx dy dz (x y z))
STRESS-INTEGRATION ACCURATE/MODERATE/SIMPLE
SURFACE PLANE/CYLINDER/CONE x y z (radius/angle)
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A.4 BASIC DATA COMMANDS
ADDITIONAL-STIFFNESS (cstiff (rstiff (tstiff)))
BOTTOM-STEEL REBARS/TENDONS type cover angle (resize)
COMPRESSION-STEEL EFFECTIVE/INEFFECTIVE CONCRETE-
DEPTH depth (VERIFY)
CONCRETE-DENSITY density
CONCRETE-MODULUS (ulsmod (slsmod (flsmod)))
CONCRETE-PROPERTIES3S8110/BS5400/DNV77/DNV89/NS3473/PARABOLIC
/S474/LINEAR/RIGOROUS/DEFINED/TENSION values ---
CONCRETE-STRESS-REDUCTION (ON/OFF/NS3473/S474)
DEFORMATION-PROPERTIES eval mu
MATERIAL-PARTIAL-SAFETY-FACTORS (lstate) gammac gammar gammap
(gammas)
METHOD STRIP (angle (miter (control)))
METHOD LAYER (nlayers (miter(contol(nskip(stiffl --- stiff6(weightl---
weight6))))))
PRESTRESS-FACTORS (Istate) pmax pmin smax smin
PRESTRESS-LOADS TOTAL/SECONDARY DIRECT nx ny nxy ---- nxz nyz
PRESTRESS-LOADS TOTAL/SECONDARY ANALYSIS/RECOVER/NONE
(number/data ---)
PRESTRESS-TENDONS type material sndata strands diameter spacing prestress REBAR-
PROPERTIES material fy (BS8110/BS5400/MC78/DNV/NS3473/S474)
(es(strn (fl)))
REDISTRIBUTION-MATRIX f11 f12 f13 f18
+ f21 f22 f23 f28
+ f3I f32 f33 f38
. . . . .
+ f81 f82 f83 f88
REINFORCEMENT-BARS type material sndata diameter spacingl (spacing2)
(HIBOND/RIBBED/INDENT/PLAIN)
RESET
SHEAR-REINFORCEMENT (diameter material xspacing yspacing)
SIGNS factnx--- ---factnyz
TENDON-PROPERTIES material fpu et(es(ec fyc )) (ALTERNATE) TOP-
STEEL REBARS/TENDONS type cover angle (resize)
UNITS faclen factor
WATER-PRESSURE-IN-CRACKS topp/OFF (botp) (BASIC/EXACT/EXTENDED)
A.5 ULTIMATE & SERVICEABILITY LIMIT STATES
CLASS (class)
CRACK-WIDTHS (ON/OFF)
DEFORMATION-LOADS MAXIMUM/MINIMUM/DIRECT (STRENGTH/SERVICE)
nx ny nxy --- nyz
DEFORMATION-LOADS ANALYSIS/RECOVER number/data ---
DEFORMATION-LOADS ON/OFF
ENVELOPE MAXIMUM/MINIMUM/DIRECT (STRENGTH/SERVICE) nx ny nxy
---- nxz nyz
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Concrete-Check – User Manual Summary of Commands
ENVELOPE ANALYSIS/RECOVER number/data ---
ENVELOPE-NAME (description)
ENVELOPE-NUMBER number
POST-DEFORMATION-LOADS MAXIMUM/MINIMUM/DIRECT
(STRENGTH/SERVICE) nx ny nxy --- nyz
POST-DEFORMATION-LOADS ANALYSIS/RECOVER number/data ---
POST-DEFORMATION-LOADS ON/OFF
RATIO (ratio)
REDESIGN (OFF/mloop)
SERVICE-CHECK (ON/OFF/S474/MC78/NS3473/BS8110/BS5400) (options---)
SERVICE-CRITERIA width (stress)
SHEAR-CHECKS DNV/DEN/MC78/BS8110/BS5400/NS3473/TRIAXIAL
(options---)
SHEAR-CHECKS (OFF/ON)
STRENGTH-CHECK (ON/OFF)
TENSION-STIFFENING (ON/OFF/LIMITED)
WATERTIGHTNESS (DNV) diffpress
WATERTIGHTNESS S474/OFF (stress)
A.6 FATIGUE LIMIT STATES
COMBINATION number DIRECT nx ny nxy ---- nxz nyz
COMBINATION number ANALYSIS/NONE (data ---)
CONCRETE-S-N-CURVE cccycles ctcycles
FATIGUE-CHECK (OFF/ON)
FATIGUE-CYCLE occurs COMPLEX/STEPPED steps/cases —
FATIGUE-DATA ccsum (rbsum (ON/OFF))
FATIGUE-LIFE years
FATIGUE-RESET
STATIC-COMBINATION DIRECT nx ny nxy ---- nxz nyz
STATIC-COMBINATION ANALYSIS ANALYSIS/NONE (data) ----
STEEL-S-N-CURVE curve stressl cyclesl slopel
A.7 IMPLOSION CHECKS
IMPLOSION-CHECK (ON/OFF)
IMPLOSION-CYLINDER length radius (width (fixity))
IMPLOSION-IMPERFECTIONS eo
IMPLOSION-LOADS pressure (axial (bending (shear (torsion))))
A.8 PANEL STABILITY CHECKS
PANEL-DIMENSIONS length width (fixity)
PANEL-IMPERFECTIONS eo
PANEL-LOADS pressure (nx (ny (nxy)))
PANEL-STABILITY-CHECK (ON/OFF)
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Concrete-Check – User Manual Summary of Commands
A.9 FILE HANDLING
KEY-FIELDS keysyml (keysym2 (--))
KEY-RANGES mini maxi (mint max2 (----))
NEW-SYMBOL symbol (value)
SYMBOL-VALUE symbol value
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Concrete-Check – User Manual Sample Output
Appendix - B Sample Output
B.1 DATA ECHO AND PRINTING
The ECHO and LIST-INPUT-DATA commands may be used to control printing of input
data as it is processed.
The ECHO command causes each command to be echoed to the output file (or terminal) as
it is read in. The LIST-INPUT-DATA command causes interpreted command printout to be
produced for the control data. This output is more informative but lengthier than the output
produced by ECHO.
The PRINT-DATA command may be used at any time to obtain printout of the current input
data. The format of this printout is shown by Figures B.1-1 to B.1-3. It is recommended that
this facility is used immediately prior to DO-CHECKS to obtain a data listing for the
subsequent checks. The fatigue data page (B.1-3) is only printed if FATIGUE-CHECK is
currently switched on.
B.2 CODE CHECK OUTPUT
Output from CONCRETE-CHECK is of four types:
− a brief summary report showing only the final results of the checks on each location
or set. This output is illustrated by Figure B.2-1 for all of the checks available in the
program;
− one (or more) pages of detailed output per location or node checked. This output
can be very lengthy but can be controlled with the OUTPUT-LEVEL command.
Figures B.2-2 to B.2-6 show typical output for the following checks:
o ULS - Strip Method to BS8110
o ULS - Finite Layered Approach
o ULS - Shear Checks
o SLS - Crack Width Calculations
o FLS - Fatigue Calculations;
− implosion and Panel Stability Checks provide one page of output per check.
Figures B.2-7 and B.2-8 illustrate these checks;
− output to backing file for subsequent access by CONCRETE-PLOT.
Further detailed levels of output are available via the SUBROUTINE-TRACE and DEBUG
commands. It is recommended, however, that these should only be used by experienced
users.
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Concrete-Check – User Manual Sample Output
B.3 PLOT OUTPUT
The BEGIN-PLOT and FINISH-PLOT commands may be used to produce plot files for the
following code check results:
− ULS, Total Main Steel Areas
− ULS, Link Steel Areas
− SLS, Maximum Crack Widths
− SLS, Maximum Rebar Stresses
− FLS, Concrete Fatigue Lives
− FLS, Minimum Rebar Fatigue Lives
− FLS, Minimum Tendon Fatigue Lives
These plot files may subsequently be plotted using the PLOTIT utility program. Sample
output is included in Figure B.3-1,
The WRITE command may be used to force CONCRETE-CHECK to write code check
results to backing file for subsequent access by CONCRETE-PLOT. This latter program
may then produce plottable files of selected results. Refer to the CONCRETE-PLOT User
Manual for more details.
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Concrete-Check – User Manual Sample Output
FIGURE B.1-1: BASIC PRINT-DATA OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.1-2; GEOMETRIC PRINT DATA OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.1-3: FATIGUE PRINT DATA OUTPUT
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FIGURE B.24: TYPICAL SUMMARY OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.2-2: ULS - STRIP METHOD OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.2-3: ULS - FINITE LAYERED METHOD OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.2-4: ULS - SHEAR CHECK OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.2-5: SLS - CRACK WIDTH OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B02-6a FLS FATIGUE LIFE OUTPUT - PAGE 1.
e
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Concrete-Check – User Manual Sample Output
FIGURE B2-6b: FLS - FATIGUE LIFE OUTPUT - PAGE 2
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Concrete-Check – User Manual Sample Output
FIGURE B.2-6c: FLS - FATIGUE LIFE OUTPUT - PAGE 3
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FIGURE B.2-7: IMPLOSION CHECK OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.2-8: PANEL STABILITY CHECK OUTPUT
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Concrete-Check – User Manual Sample Output
FIGURE B.3-1: SAMPLE PLOT OUTPUT
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Concrete Check – User Manual SESAM FE Interface
Appendix - C SESAM FE Interface
C.1 INTRODUCTION
CONCRETE-CHECK is available as a post-processor to the SESAM FE system either
directly or through the CONCRETE-ENVELOPE program.
Both shell and solid element models of the structure may be processed. Section C.2 lists
available element types.
CONCRETE-CHECK will obtain geometric and element stress data from the SESAM
Interface File produced by PREPOST, However, PREPOST will not produce nodally
averaged stresses. These results must be added by the SIF-AVERAGE program which
allows the user to define groups of elements for post-processing and nodally average
stresses in consistent axes, for selected load cases. The user should refer to the SIF-
AVERAGE manual for details. Section C.3 of this Appendix does, however, contain details
of the required organisation of stresses in the interface file.
Section C.4 contains details of command formats that are dependent on the FE system.
Commands affected are SUPER-ELEMENT, ENVELOPE, COMBINATION, STATIC-
COMBINATION and PRESTRESS-LOADS.
The final section of this appendix, C.5, gives details of the files required for CONCRETE-
CHECK to run successfully.
C.2 AVAILABLE ELEMENT TYPES
Only the following SESAM elements are currently processed by the CONCRETE suite:
− IHEX, Solid brick element (20 nodes);
− IPRI, Solid prismatic element (15 nodes);
− LHEX, Solid brick element (8 nodes);
− TPRI, Solid prismatic element (6 nodes);
− IQQE, SCQS, Quadrilateral shell element (8 nodes);
− ILST, SCTS, Triangular shell element (6 nodes);
− LQUA, FQUS, Quadrilateral shell element (4 nodes);
− CSTA, FTRS, Triangular shell element (3 nodes).
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Concrete Check – User Manual SESAM FE Interface
Other element types may be present in the super-element being processed, but are currently
ignored.
C.3 STRESS EXTRACTION
A 'Norsam Formatted' SESAM Interface File (SIN) is the required link between SESAM,
SIF-AVERAGE and CONCRETE. This should be produced using the PREPOST program
using the SET PERMANENT-WORKING-FILE command when reading the results file
produced by SESTRA.
PREPOST may also be used to create load combinations for use in CONCRETE-
ENVELOPE and CONCRETE-CHECK. These combined cases and the original constituent
cases are then available for code checking.
The CONCRETE suite does not handle complex load cases in the same form as SESAM.
Single complex cases from the analysis should be converted to separate real and imaginary
cases by PREPOST so that they can be processed by SIF-AVERAGE. This is possible by use
of the CREATE RESULT-COMBINATION command.
Note also that the CONCRETE suite does not support run numbers and occurrence numbers
of load cases. Again, PREPOST can be used to create load combinations that have a constant
run number to avoid this restriction.
Once all necessary combined cases have been defined, SIF-AVERAGE can be used to
subdivide the super-element into groups of elements across which nodal averaging is valid.
Nodally averaged stresses should then be produced for all nodes in these groups for selected
load cases. The stresses and group information will be stored back to the SIN, where they can
be accessed by CONCRETE-ENVELOPE and CONCRETE-CHECK.
These nodally averaged stresses for shell elements form the basis of the loads per unit width
produced for enveloping by CONCRETE-ENVELOPE, or accessed directly by
CONCRETE-CHECK.
However, for a given location around a section for any group of solid elements, the
CONCRETE programs must interpolate between the stresses at the closest nodes to obtain
these loads. The programs convert these extreme fibre stresses into the location axis system
and integrate them to produce the eight basic loads per unit width at the location, Details of
this method may be found in the Theory Manual.
Both SESAM and CONCRETE work on a tensile-positive compression-negative system for
stresses, and no sign conversion is needed for basic direct stresses.
Both SESAM and CONCRETE use a sign convention for shear that causes elongation in the
+ve quadrants (XY, XZ, YZ) for positive shear stress. No sign conversion is needed for
shear.
C.4 SYSTEM DEPENDENT COMMANDS
The following CONCRETE-CHECK commands take on a different format when used with
the SESAM interface.
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The format of the SUPER-ELEMENT instruction is as follows: SUPER-
ELEMENT prefix filename (super-element)
where 'prefix' is a file prefix for the required SIN file and 'filename' is the SIN filename, and
'super-element' is the hierarchy reference number of the required super-element. If only one
super-element exists within the SIN, this parameter is not required.
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The ENVELOPE, PRESTRESS-LOADS, DEFORMATION-LOADS, POST-
DEFORMATION-LOADS, COMBINATION and STATIC-COMBINATION commands all
take the following simple formats when interfaced with SESAM:
ENVELOPE ANALYSIS lcase
PRESTRESS-LOADS TOTAL/SECONDARY ANALYSIS lcase
DEFORMATION-LOADS ANALYSIS lcase
POST-DEFORMATION-LOADS ANALYSIS lcase (ulsfac (slsfac))
COMBINATION number ANALYSIS lease
STATIC-COMBINATION ANALYSIS lease
where lcase is the basic or combined load case number to use for the appropriate loading.
Note that there is no provision in these commands for a run number or occurrence number.
The optional parameters, ulsfac and slsfac, are factors to be applied to recovered post
deformational analysis load cases (default values 1.0). If only ulsfac is specified, slsfac
defaults to the same value.
C.5 FILE HANDLING
As mentioned above, CONCRETE-CHECK acts on the 'Norsam Formatted' SESAM
Interface File produced by PREPOST and modified by the SIF-AVERAGE program to
contain nodally averaged stresses for groups or sets of elements in a consistent axis system.
For CONCRETE-CHECK to run, this file must be present on the default device.
Several SIN files may be produced for different super-elements. The referenced super-
element SIN file must be present.
CONCRETE-ENVELOPE also writes results to the SIN, and these may also be accessed if
the file is on the current device.
The file name for the SIN is created using the data on the SUPER-ELEMENT command, as
follows:
<prefix> <filename>.SIN
where the extension (.SIN) signifies the Norsam formatted direct access file.
The SESAM system uses streams 10, 11 and 12 for internal file handling. These streams, as
well as streams 5, 6, 51, 52 and 53 should not be used by the CHANGEINPUT-STREAM
command.
CONCRETE-PLOT results are written back to this same SIN file as required. The WRITE
command alone causes this. No further file definition is needed.
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Appendix - D ASAS FE Interface
D.1 INTRODUCTION
CONCRETE-CHECK is available as a post-processor to the ASAS package of programs,
either directly or through the CONCRETE-ENVELOPE program.
Only certain ASAS element types may be accessed by the CONCRETE suite. Available
elements are listed in Section D.2 of this Appendix.
The ASAS storage convention for stresses is described briefly in Section D.3 and details are
given as to how this interfaces to the CONCRETE system for post-processing.
Section D.4 of this Appendix describes the format of any commands that are specific to the
ASAS interface. Commands affected are SUPER-ELEMENT, ENVELOPE,
COMBINATION, STATIC-COMBINATION and PRESTRESS-LOADS.
The final section of this Appendix, D.5, described the files required for a successful run of
CONCRETE-CHECK.
D.2 AVAILABLE ELEMENT TYPES
CONCRETE-CHECK can work directly from ASASPOST results for shell and brick
elements. The following three, four, six and eight noded shells can be handled:
GCS6, GCSE, TCS6, TCS8, TBC3, QUS4, QUM8,
QUM4, TRM6, TRM3, SLB8, TRB3, SND6, SND8
However, not all of the above shell elements produce all of the stress resultants required by
CONCRETE. For example, the membrane elements (QUM8, TRM6, QUM4, TRM3) do
not produce bending stresses, and the bending elements (SLB8 and TRB3) do not produce
membrane stresses. Only the thick shell elements (TCS8 and TCS6) produce all
components of stress including out of plane shear and these are recommended for use in
modelling the concrete structure. Where stresses are not available, they are set to zero.
CONCRETE-CHECK can also handle a full range of solid (brick) elements (except for the
BR32 element). The following can be handled:
BRK6, BRK8, BR15, BR20
Shell and brick elements may not be mixed in a single set or group of elements. Other than
this, the two element types may exist in the same model.
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D.3 STRESS EXTRACTION
The CONCRETE suite of programs can either be run as a direct post-processor to ASAS
(using the STRESS-AXES command), or can use ASAS POST to produce nodally averaged
stresses in plate or solid structures across groups. ASAS POST also defines consistent axis
systems across panels and solid element groups. Optionally, ASAS LOCO may also be run
to combine load cases. Real and imaginary components, and all prestress cases should be
kept separate through this analysis.
When using shell elements, the CONCRETE programs obtain their eight components of load
directly from the nodally averaged stresses at the node being considered. These stresses may
be calculated internally and stored by ASAS POST as a set of direct stresses per fibre (top,
bottom, middle) or may be generated internally following the rules for the STRESS-AXES
command. CONCRETE determines its membrane loads from the middle fibre results, and its
bending loads from the difference in extreme fibre stresses. Because the ASAS and
CONCRETE sign conventions for tension and compression are the same, these loads will
automatically be of correct sign.
ASAS thick shell elements also produce out-of-plane shear loads which are also nodally
averaged internally or by ASAS POST. The sign convention in Appendix A of the ASAS
Manual shows that these loads are identical in sign to the CONCRETE suite loads (Figure
4.3-1) and no sign conversion is necessary.
However, for any given location around a section through any group of solid elements, the
CONCRETE suite programs must interpolate between the stresses at the closest nodes to
obtain these loads. The programs convert the stresses into the location axis system and
integrate them to produce the eight basic loads per unit width required in the checks. Full
details of this approach is included in the CONCRETE Theory Manual.
Both ASAS and CONCRETE work on a tensile-positive, compression-negative system for
stresses, and no sign conversion is needed for basic direct stresses.
Both ASAS and CONCRETE use a sign convention for shear that causes elongation in the
+ve/+ve quadrant (XY, XZ, YZ) for positive shear stress. No sign conversion is needed for
shear.
D.4 SYSTEM DEPENDENT COMMANDS
The following CONCRETE-CHECK commands take on a different format when used with
the ASAS interface.
The format of the SUPER-ELEMENT card is as follows:
SUPER-ELEMENT dataarea project structure (SYOP)(number)(file)
where dataarea is the required data area in words;
project is the four character project name;
structure is the four character structure name;
SYOP signifies that system options are to be read;
number is the assembled super-element number given at the end of the
assembly run in the component tree diagram;
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file file stem for CONCRETE-PLOT output.
SYOP is optional. If given, the program expects to read two lines of system options after the
SUPER-ELEMENT command, each in 40I2 format. This is an advanced feature that should
not generally be used without advice from support staff
The component 'number' is also optional, but must be specified for a component analysis run.
This is the number assigned to the component when the final structure is assembled. It is
printed in the output from that run.
The ENVELOPE, PRESTRESS-LOADS, DEFORMATION-LOADS, POST-
DEFORMATION-LOADS, COMBINATION and STATIC-COMBINATION commands all
take the following simple formats when interfaced with ASAS:
ENVELOPE ANALYSIS lcase
PRESTRESS-LOADS TOTAL/SECONDARY ANALYSIS lcase
DEFORMATION-LOADS ANALYSIS lcase
POST-DEFORMATION-LOADS ANALYSIS lcase ( ulsfac ( slsfac ))
COMBINATION number ANALYSIS lcase
STATIC-COMBINATION ANALYSIS lcase
Where lcase is the basic or combined load case number to use for the appropriate loading.
The optional parameters, ulsfac and slsfac, are factors to be applied to recovered post
deformational analysis load cases (default values 1.0). If only ulsfac is specified, slsfac
defaults to the same value.
D.5 FILE HANDLING
CONCRETE-CHECK acts on the files produced by the preceding ASAS or CONCRETE-
ENVELOPE analyses. Optionally, ASAS LOCO and ASAS POST may be run after ASAS
to combine load cases (although this may also be performed in CONCRETE-ENVELOPE)
and nodally average stresses. Since ASAS LOCO produces identically formatted files to
ASAS, either can be used as required.
The appropriate physical files from the ASAS (or ASAS LOCO) run, and if necessary the
ASAS POST and CONCRETE-ENVELOPE runs, must be present on disc for CONCRETE-
CHECK to run. To produce these files, the programs should have been run with appropriate
SAVE and WRITE options.
In all cases there will be the Project File which contains information about all other files in
the current set of analyses. The name of this file is derived from the four character Project
Name defined on all JOB cards in the runs. For example, if the project name is PRDH, then
the Project File will be PRDH10.
For an ASAS or ASAS LOCO analysis with a 'SAVE LOCO FILES' command (or
equivalent) in its preliminary deck, there will be a physical file containing the stress and
displacement information from that analysis. For a single step analysis the physical file
name will be derived from the second four character name on the JOB card of the ASAS or
ASAS LOCO preliminary deck, or from the FILES command.
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For example, if this name had been RNDH, then the backing file containing stresses (and
displacements) would be RNDH35. For a post-processing run on a substructured analysis,
the file name for the results is derived from the second four character name on the JOB card
of the relevant stress recovery run. If this name has been SRGP then the file would be
SRGP35.
For an ASAS POST run with a SAVE INTE FILES card in its preliminary deck, there will
be a physical file containing nodal stress data. This file will be based on the four character
name given on the JOB card of the ASAS POST data file. If the name is ASPO, then the file
name will be ASPO12. Multiple ASAS POST runs may produce more than one '12' file. No
ASAS POST files are needed if internal stress averaging is to be used.
When using results from CONCRETE-ENVELOPE, appropriate envelope backing files
should be present on disc. For runs of CONCRETE-ENVELOPE with appropriate options
set (ENVELOPE ON, WRITE ON), these results will be stored in '21' files. If the file name
given on the JOB card is COPO, then CONCRETE-ENVELOPE will produce a COPO21
file.
CONCRETE-CHECK will produce a backing file containing code check results if these
results are required to be saved for CONCRETE-PLOT (via the WRITE ON command).
This will be a '22' file with the same file stem as given on the SUPER-ELEMENT
command. If this name is COCH, then the file will be COCH22.
The ASAS system reserves streams 1 to 50 for internal file handling and I/O. These streams
and 51, 52 and 53 should not be used for CHANGE-INPUT-STREAM commands.
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