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					                               Concrete Suite -
                              Application Manual

                                             Version 12




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          Concrete Suite - Application 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




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Concrete Suite – Application Manual                                                                                   Table of Contents



                                                TABLE OF CONTENTS


1      INTRODUCTION ........................................................................................................................ 1-1
        1.1  STRUCTURE OF THE CONCRETE SUITE ................................................................. 1-1
        1.2  STRUCTURE OF THIS MANUAL................................................................................ 1-2
2      CONCRETE-CHECK OVERVIEW ............................................................................................ 2-1
        2.1  STRUCTURAL LOADS ................................................................................................. 2-1
        2.2  SIGN CONVENTION AND UNITS............................................................................... 2-1
        2.3  PROGRAM LIMITATIONS ........................................................................................... 2-2
        2.4  INTERFACE WITH FE SYSTEMS ............................................................................... 2-3
        2.5  NOTES ON CONCRETE-ENVELOPE .......................................................................... 2-4
3      SIMPLE STAND-ALONE ULTIMATE LIMIT STATE CHECKS ............................................ 3-1
        3.1  INTRODUCTION ........................................................................................................... 3-1
        3.2  TEST PROBLEM ............................................................................................................ 3-1
        3.3  STRUCTURE OF THE DATA FILE .............................................................................. 3-2
             3.3.1 Run Initialisation Data......................................................................................... 3-3
             3.3.2 Slab Data ............................................................................................................. 3-4
             3.3.3 Load Case Data ................................................................................................... 3-4
             3.3.4 Summarising the Input Data ................................................................................ 3-4
             3.3.5 Analysis Method ................................................................................................. 3-5
        3.4  OUTPUT DESCRIPTION............................................................................................... 3-5
             3.4.1 Description of Summary Output File.................................................................. 3-5
             3.4.2 Description of Detailed Output File .................................................................... 3-6
4      ADVANCED FEATURES ........................................................................................................... 4-1
        4.1  INTRODUCTION ........................................................................................................... 4-1
        4.2  PRESTRESS DATA........................................................................................................ 4-1
             4.2.1 Definition of Prestress Tendon Data ................................................................... 4-2
             4.2.2 Discussion of Results .......................................................................................... 4-3
        4.3  SLAB SECTION REDESIGN FUNCTION ................................................................... 4-3
        4.4  USE OF MULTIPLE INPUT FILES (SEE NOTE 1) ..................................................... 4-4
        4.5  ANALYSIS OF MULTIPLE LOCATIONS ................................................................... 4-6
             4.5.1 Data File for Example 3 ...................................................................................... 4-6
             4.5.2 Plotting Facility ................................................................................................... 4-7
5      SERVICEABILITY LIMIT STATE CHECKS............................................................................ 5-1
        5.1  INTRODUCTION ........................................................................................................... 5-1
        5.2  SLS EXAMPLE PROBLEM ........................................................................................... 5-1
        5.3  SLS SPECIFIC INSTRUCTIONS................................................................................... 5-2
        5.4  RESULTS FROM SLS CHECK ..................................................................................... 5-2
6      FATIGUE LIMIT STATE CHECK ............................................................................................. 6-1
        6.1  INTRODUCTION ........................................................................................................... 6-1
        6.2  FLS EXAMPLE PROBLEM ........................................................................................... 6-1
        6.3  FLS SPECIFIC INSTRUCTIONS................................................................................... 6-2
             6.3.1 Initialisation Instructions ..................................................................................... 6-2
             6.3.2 Load Combination Data ...................................................................................... 6-3
        6.4  OUTPUT DESCRIPTION............................................................................................... 6-5
7      IMPLOSION AND PANEL STABILITY CHECKS ................................................................... 7-1
        7.1  INTRODUCTION ........................................................................................................... 7-1
        7.2  IMPLOSION EXAMPLE PROBLEM ............................................................................ 7-1
             7.2.1 Implosion Check Specific Input Data .................................................................. 7-2
             7.2.2 Output Description .............................................................................................. 7-3
        7.3  PANEL STABILITY EXAMPLE PROBLEM ............................................................... 7-3
             7.3.1 Panel Stability Specific Input Data...................................................................... 7-4
             7.3.2 Output Description .............................................................................................. 7-5
8      POST PROCESSING OF SESAM MODELS ............................................................................. 8-1
        8.1  GENERAL CAPABILITIES ........................................................................................... 8-1
        8.2  EXAMPLE PROBLEMS ................................................................................................ 8-1
        8.3  USE OF SIF-AVERAGE PROGRAM ............................................................................ 8-2
        8.4  CODE CHECKING SUPERELEMENT BB00T103 ...................................................... 8-3
             8.4.1 Run Control Data ................................................................................................ 8-5


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Concrete Suite – Application Manual                                                                                 Table of Contents

                  8.4.2 Definition Of Locations To Be Checked ............................................................. 8-5
                  8.4.3 Load Case Data ................................................................................................... 8-5
         8.5      OUTPUT FROM EXAMPLE 8 ...................................................................................... 8-6




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Concrete Suite – Application Manual                                                                     Introduction




1      INTRODUCTION

         The CONCRETE suite of programs allows the user to rapidly check the design and
         integrity of a concrete structure against a number of codes of practice. The programs are
         applicable to a wide variety of structures deployed both onshore and offshore. The purpose
         of this manual is to explain, in a practical manner, how to use these facilities for the
         analysis of reinforced and prestressed concrete structures.


1.1      STRUCTURE OF THE CONCRETE SUITE


         The CONCRETE suite consists of four separate, but integrated programs:

                       -           CCAL - CONCRETE-CHECK (Standalone)

                       -           CCAS - CONCRETE-CHECK (Integrated with ASAS)

                       -           CEAS - CONCRETE- ENVELOPE (Integrated with ASAS)

                       -           CPAS - CONCRETE-PLOT (Integrated with ASAS)
         All the programs are fully documented in their respective User Manuals, and the
         underlying theory of the programs is detailed in the CONCRETE Suite Theoretical
         Manual. These manuals should also be referenced whilst reading this one.
         CONCRETE-CHECK performs the main analysis function, checking a user defined cross-
         section of the structure to the desired code of practice. The program can perform ultimate,
         serviceability or fatigue limit state checks on the section. Buckling and implosion checks
         can also be performed. CONCRETE-CHECK can be used in three distinct modes:
                 − as a stand-alone program. All data on the dimensions, loads, reinforcement and
                   limits of the design at each location to be checked must be defined by the user in
                   the command file;

                 − as a post-processor to a finite element (FE) program. The dimensions and loads
                   can be obtained from the FE results file; all the user needs to specify are the FE
                   load case, reinforcement, limits and locations to be checked;

                 − as a post-processor to the CONCRETE-ENVELOPE program, the user input defining
                   the reinforcement, limits and which load envelopes are to be checked.

         These modes of operation are illustrated in Figure 1.1-1 .
         The standard output from CONCRETE-CHECK comprises two files, a summary file and a
         list file. The summary file summarises in one line the results obtained at a location.
         The listing file produces a much more detailed listing, listing all the input data and
         intermediate results as well as displaying the pass/fail status for the location. CONCRETE-
         CHECK can also generate an optional plot file to allow it to interface with user written plot
         routines.




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Concrete Suite – Application Manual                                                                     Introduction


         In the third operational mode described above, the CONCRETE-ENVELOPE program
         may be used to pre-process the results from an FE analysis for subsequent code-checking.
         This operation consists of producing a set of load envelopes (maximum/minimum ranges)
         for a group of user defined locations, from which a worst envelope for the group (or
         group envelope) can be constructed. Code-checking of the group envelope can then
         identify whether further analysis of the locations within the group is required. Similarly
         global envelopes constructed from a set of group envelopes can also be generated.
         CONCRETE-PLOT performs the following tasks, it:

           •            allows the user to select envelopes of load at given locations produced by
                        CONCRETE-ENVELOPE, extract these and copy them to a plot interface file
                        for subsequent display;

          •             allows the user to similarly select code check results produced by CONCRETE-
                        CHECK for transfer to plot interface files format and subsequent display.


1.2      STRUCTURE OF THIS MANUAL


         Chapter Two gives a brief overview of the CONCRETE-CHECK program, its limitations
         and conventions.

         The next five chapters show how CONCRETE-CHECK can be used to perform various
         types of analysis. Chapter Three uses a basic ultimate limit state (ULS) analysis to explain
         the structure and contents of the command file used to control a run of the program.
         Chapter Four includes prestress tendons, thereby increasing the complexity of the
         concrete slab under consideration and also expands the scope of the checks performed.
         Chapter Five introduces the serviceability limit state (HS) checks that can be performed.
         Chapter Six covers the fatigue limit state (FLS) checks. Chapter Seven details implosion
         and panel stability analyses, which as well as loading and section details require the panel
         dimensions to be defined. All five chapters contain examples which show the minimum
         set of instructions required to perform each type of analysis.

         The example applications used so far have all required the user to input all the data
         needed to perform the analysis. CONCRETE-CHECK will interface with various FE
         systems to allow the results from an FE analysis to be rapidly post-processed. Chapter
         Eight demonstrates how CONCRETE-CHECK is interfaced with the FE program and
         how it is used to analyse specific locations in the example FE models.

         This manual does not describe in detail the application of CONCRETE-ENVELOPE, this
         is because the purpose of the program is to create a database of loadings for subsequent
         code-checking. To work effectively this database needs to be carefully designed to match
         both the loading and code-checking strategy of the structure under analysis. At present
         there is insufficient experience in code-checking large offshore concrete structures to be
         able to provide the user with pertinent examples and guidance.

         All the data files and FE results files used in this manual are provided in an example
         directory, refer to the system manager for details of how to access this directory.



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  Concrete Suite – Application Manual                                                                                  Introduction




                                                                                                    SUMMARY
                                                                                                      FILE
      USER                                    CONCRETE
    COMMAND                                    CHECK
      FILE                                    PROGRAM
                                                                                                     LIST FILE




                                       STAND-ALONE MODE

  USER
COMMAND                                                                                               SUMMARY
  FILE                                                                                                  FILE
                                                CONCRETE
                                                 CHECK
   FE                                           PROGRAM
RESULTS                                                                                                   LIST
  FILE                                                                                                    FILE



                                       FE POST-PROCESOR MODE

   FE
RESULTS                                                                                                   LIST
  FILE                                                                                                    FILE
                                                 CONCRETE
                                                 ENVELOPE
  USER                                           PROGRAM                                            PROCESSED
COMMAND                                                                                                FE
  FILE                                                                                               RESULTS




                                                                                                      SUMMARY
                                                                                                        FILE
                                                 CONCRETE
                                                  CHECK
                                                 PROGRAM
                                                                                                          LIST
  USER                                                                                                    FILE
COMMAND
  FILE


                    CONCRETE-ENVELOPE POST-PROCESSOR MODE



               Figure 1.1-1 CONCRETE–CHECK Modes of Operation




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Concrete Suite – Application Manual                                                          Concrete-Check Overview


2     CONCRETE-CHECK OVERVIEW

       The CONCRETE-CHECK program has been developed to efficiently check concrete
       structures against codes of practice and industry guidelines. The program can analyse
       prestressed and reinforced concrete slabs, plates and shells with symmetric and/or
       asymmetric reinforcements, subjected to either uniaxial or multi-axial stress fields.

       Two methods are available to solve a loaded slab for concrete fibre strains and
       reinforcement steel stresses, the strip method and the layered method. It is important that
       the user understands the applicability of both methods:

               − the simpler BS8110 strip method can be used where the loads are primarily in
                  one direction and there is no significant in-plane shear or torsion;

               − the more sophisticated finite layered method is capable of solving concrete slabs
                  under a general state of stress.

       Both methods allow the user to define reinforcement and prestressing tendons at any depth
       and angle for each section under analysis.


2.1    STRUCTURAL LOADS


       The pattern of loading on any unit width of slab/plate or shell can comprise axial loads,
       bending moments and out of plane shear. In general the loading can be represented by
       the following eight load components:

         Nx        -        Axial load per unit width in the X-direction;
         Ny        -        Axial load per unit width in the Y-direction;
         Nxy       -        In plane shear force per unit width of slab;
         Mx        -        Bending moment per unit width in the X-direction about the Y-axis;
         My        -        Bending moment per unit width in the Y-direction about the X-axis;
         Mxy       -        Torsional moment per unit width of slab;
         Nxz       -        Out of plane shear force per unit width acting on the X-Z plane of
                            slab;
         Nyz       -        Out of plane shear force per unit width acting on the Y-Z plane of
                            slab.

       The above forces for a unit width of slab are shown diagrammatically in Figure 2.1-1 .

       Concrete cylindrical and panel structures of any dimensions, subjected to combined
       loading, can be checked for implosion and buckling respectively.


2.2    SIGN CONVENTION AND UNITS


       In all examples used in this manual the sign convention and units have been carefully
       detailed. A quick definition of the system is given below, further information can be
       obtained from the relevant User Manual.


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Concrete Suite – Application Manual                                                          Concrete-Check Overview


       The CONCRETE–CHECK sign conventions are: tensile–positive, positive moments
       cause tensile stress in the bottom fibres of the slab and positive shear causes elongation in
       both the (X>0, Y>0) and (X<0, Y<0) quadrants.

       The basic unit of length adopted for slab section properties is the millimetre, but note that
       panel and column dimensions adopt the metre as the unit of length. The unit of force is the
       meganewton, but is specified in a linearised form, i.e per metre width of slab. Thus forces
       are actually dimensioned MN.m-1, and moments MNm.m-1 (or MN). Stress and pressure
       units are MNm-2 (or Nmm-2). Other basic units are time in seconds and angles in degrees.

       Most FE packages give the user a wide choice of units; if the above units have not been
       adopted in the analysis, then conversion factors must be specified when using the direct
       FE interface to CONCRETE–CHECK. CONCRETE–ENVELOPE works in and
       maintains the FE analysis units.


2.3    PROGRAM LIMITATIONS


       The main limitations of the CONCRETE–CHECK programs are as follows:

           −     up to ten layers of concrete, rebars, and prestress tendons can be specified within
                 any section and the total number of TOP–STEEL and BOTTOM–STEEL cards
                 specified for either rebars or prestress tendons must not be greater than ten. The
                 definition of layers can be RESET to allow subsequent redefinition;

           −     a maximum of ten rebar and ten prestress tendon properties can be specified
                 within the program using the REBAR–PROPERTIES and TENDON–
                 PROPERTIES commands;

           −     a maximum of ten rebars and ten prestress–tendon geometries can be created
                 simultaneously using the REINFORCEMENT–BARS and PRESTRESS–
                 TENDON cards. These geometries can then be referenced by the
                 TOP/BOTTOM–STEEL cards;

           −     a cyclic fatigue load can be defined with up to twenty–five steps;

           −     the program is capable of referencing up to a maximum of two hundred and
                 fifty analysis load cases and/or combinations in one CONCRETE run;

           −     a maximum of ten STEEL–S–N–CURVES can be created for referencing by
                 REINFORCING–BARS and PRESTRESS–TENDON cards;

           −     when specifying commands, the instruction lines must not be greater than eighty
                 characters long;

           −     a maximum of fifteen KEY–FIELDS are allowed to be defined in the program;

           −     it is not possible to redefine a keyed filing system once it has been used for the
                 storage of envelopes.


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Concrete Suite – Application Manual                                                          Concrete-Check Overview

        Other limitations will be included in the description of the relevant instruction.


2.4    INTERFACE WITH FE SYSTEMS


       When interfacing with any FE system, the CONCRETE-ENVELOPE and CONCRETE-
       CHECK programs use three methods to select locations around a structure for enveloping
       and/or subsequent code checking. The methods available for a particular model depend on
       the types of element being used.

       The three methods available are:

         1)       for structures modelled using shell elements to represent the concrete shells, the
                  user can identify individual locations by node numbers alone;

         2)       for structures modelled using shell elements to represent the concrete shells, a
                  powerful facility exists whereby the program automatically selects and classifies
                  all nodes that exist across a panel (the panel being defined as a subset of shell
                  elements);

         3)       for structures modelled using solid elements to represent the concrete shells,
                  CONCRETE-ENVELOPE and CONCRETE-CHECK accept a geometric
                  definition for locations to be checked in the structure. Single locations or entire
                  sections can be identified by intersecting vectors or surfaces with a given subset
                  of solid elements. This method of definition allows through thickness direction
                  and section axes to be created with the minimum of input data.

       When interfacing with the ASAS FE system all three methods are applicable, but
       currently only Method 3 is available when interfacing with the SESAM FE system
       because CONCRETE is limited to interfacing with SESAM solid element models.

       All locations for code-checking within the CONCRETE suite are allocated a class which
       defines the position of this inspection point. The four classes currently valid are:

                  Class 1            -         Panel Corners;
                  Class 2            -         Panel Edges;
                  Class 3            -         All other Internal Panel points;
                  Class 4            -         Section Locations.

       The class of a node is used in CONCRETE-CHECK to define the type of check to be
       performed and to control the creation of certain parameters.

       When CONCRETE-ENVELOPE or CONCRETE-CHECK is being used to check one or
       more user-defined locations, then the user has to specify the class of the locations.

       There are powerful facilities available within the program, which are useful for selecting
       large areas of the structure. These are described below:

         −        the SAMPLE and SWEEP facilities are used for structures modelled using shell
                  elements to represent the concrete. For a panel represented by a specified set of
                  shell elements, the program automatically identifies and classifies nodes on the

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Concrete Suite – Application Manual                                                          Concrete-Check Overview

                  panel. All or a standard sample of classified nodes are then selected for
                  enveloping and/or subsequent code-checking;

         −        the SECTION facility is used for structures modelled using solid elements to
                  represent the concrete. The user specifies a set or group of elements and defines
                  the type and geometry of a surface to intersect with these elements. Currently
                  PLANE, CYLINDER and CONE surfaces are used to create the desired section.
                  The user then specifies a number of inspection points along this section for
                  enveloping and/or subsequent code-checking.


2.5    NOTES ON CONCRETE-ENVELOPE


       CONCRETE-ENVELOPE produces maximum/minimum envelopes for each individual
       load component at each individual location specified by the above facilities. These may be
       stored in a file. A useful facility in this program is its ability to produce class envelopes
       which are global envelopes that bound all individual node envelopes for a region (PANEL
       or SECTION).

       A further facility enables the user to BEGIN and FINISH global envelopes which are set
       up to encompass any number of individual envelopes. This facility is useful in creating
       envelopes over several panels, sections or even super-elements. Both class and global
       envelopes can be stored in a file in the same way as individual envelopes.

       To code check selected locations, the CONCRETE-CHECK program can be used directly,
       interfaced to an FE system or used via the CONCRETE-ENVELOPE program. However
       when code checking by class (via PANEL or SECTION instructions) or global regions,
       CONCRETE-CHECK can only be used after CONCRETE-ENVELOPE has processed
       the FE system results.




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Concrete Suite – Application Manual                                                          Concrete-Check Overview




                          Figure 2.1-1 Sign Convention For Concrete Suite



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Concrete Suite – Application Manual                                  Simple Stand-Alone Ultimate Limit State Checks



3     SIMPLE STAND-ALONE ULTIMATE LIMIT STATE CHECKS


3.1    INTRODUCTION

       The ultimate limit state (ULS) requires that the strength of the structure should be adequate
       to withstand the design loading. The primary ULS failure modes considered by
       CONCRETE-CHECK are:

                  − flexural or compression failure of a section;
                  − shear failure;
                  − tensile failure of reinforcement.

       The example used in this chapter involves an ultimate strength check of the reinforced
       concrete slab shown in Figure 3.1.-1. The slab is acted upon by the combined loading
       shown. Both the STRIP and LAYER methods are used for the check. The example is a
       simple stand-alone test problem, i.e. it does not include recovery of loads directly from an
       FE analysis or from an FE analysis via CONCRETE-ENVELOPE.


3.2    TEST PROBLEM


       The data file for the sample problem is listed below.
                  !
                  ! APPLICATION MANUAL EXAMPLE 1
                  ! ============================
                  !
                  ! SIMPLE STAND-ALONE CONCRETE SLAB ULTIMATE STRENGTH CHECK
                  ! USING BOTH STRIP AND LAYERED METHODS
                  !
                  ! RUN CONTROL DATA
                  !
                  TITLE APPLICATION MANUAL EXAMPLE 1
                  *
                  CODE-CHECK ON
                  STRENGTH-CHECK ON
                  !
                  ! PROVIDE SLAB DATA
                  !
                  MATERIAL-PARTIAL-SAFETY-FACTORS 1.50 1.15 1.15 1.25
                  CONCRETE-DEPTH 300.0
                  CONCRETE-PROPERTIES BS8110 50.0 0.2
                  REBAR-PROPERTIES 1 410.0
                  REBAR-PROPERTIES 3 4 0 0 . 0 1 9 0 0 0 0 . 0
                  REINFORCEMENT-BARS 1 1 0 25.0 200.0 25.0
                  REINFORCEMENT-BARS 2 3 0 25.0 200.0 200.0
                  TOP-STEEL    REBARS 1 25.0 0.0
                  TOP-STEEL    REBARS 2 50.0 90.0
                  BOTTOM-STEEL REBARS 2 25.0 0.0
                  BOTTOM-STEEL REBARS 1 50.0 90.0
                  SHEAR-REINFORCEMENT 20 1 300 300
                  !
                  ! PROVIDE LOAD DATA
                  !
                  ENVELOPE-NAME MOMENT IN BOTH DIRECTIONS
                  ENVELOPE MAXIMUM -0.50 -0.40 0.10 0.100 0.060 0.005 0.050 0.050
                  ENVELOPE MINIMUM -0.50 -0.40 0.10 -0.100 -0.060 0.005 0.050 0.050
                  !
                  ! SELECT STRENGTH CHECKS AND ECHO INPUT DATA
                  !
                  PRINT-DATA
                  !



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Concrete Suite – Application Manual                                  Simple Stand-Alone Ultimate Limit State Checks
                  STRENGTH-CHECK ON
                  !
                  ! PROVIDE SLAB DATA
                  !
                  MATERIAL-PARTIAL-SAFETY-FACTORS 1.50 1.15 1.15 1.25
                  CONCRETE-DEPTH 300.0
                  CONCRETE-PROPERTIES BS8110 50.0 0.2
                  REBAR-PROPERTIES 1 410.0
                  REBAR-PROPERTIES 3 4 0 0 . 0 1 9 0 0 0 0 . 0
                  REINFORCEMENT-BARS 1 1 0 25.0 200.0 25.0
                  REINFORCEMENT-BARS 2 3 0 25.0 200.0 200.0
                  TOP-STEEL    REBARS 1 25.0 0.0
                  TOP-STEEL    REBARS 2 50.0 90.0
                  BOTTOM-STEEL REBARS 2 25.0 0.0
                  BOTTOM-STEEL REBARS 1 50.0 90.0
                  SHEAR-REINFORCEMENT 20 1 300 300
                  !
                  ! PROVIDE LOAD DATA
                  !
                  ENVELOPE-NAME MOMENT IN BOTH DIRECTIONS
                  ENVELOPE MAXIMUM -0.50 -0.40 0.10 0.100 0.060 0.005 0.050 0.050
                  ENVELOPE MINIMUM -0.50 -0.40 0.10 -0.100 -0.060 0.005 0.050 0.050
                  !
                  ! SELECT STRENGTH CHECKS AND ECHO INPUT DATA
                  !
                  PRINT-DATA
                  !
                  ! PERFORM STRIP METHOD CHECKS AT 0 AND 90 DEGREES AND LAYERED METHOD CHECK
                  !
                  # STRIP METHOD AT 0 DEGREES
                  METHOD STRIP 0 100
                  DO-CHECKS
                  #
                  # STRIP METHOD AT 90 DEGREES
                  METHOD STRIP 90 100
                  DO-CHECKS
                  #
                  # LAYERED METHOD
                  METHOD LAYER 10 100
                  DO-CHECKS
                  !
                  END

       Commands in the file have been grouped by similar function for ease of description, but
       apart from the basic syntax explained below the commands can appear in any order.


3.3    STRUCTURE OF THE DATA FILE


       A CONCRETE-CHECK (or ENVELOPE) data file comprises multiple instruction lines,
       each of which begins with a keyword. Whilst the keyword can be abbreviated it is common
       practice to produce it in full to aid comprehension. This policy will be adopted here. There
       are usually options and parameters following the keyword, these are fully detailed in the
       User Manuals. Occasionally these options and parameters may need to extend over more
       than one line (eighty characters), in which case subsequent continuation lines must use the
       continuation character + in the first column.

       There are three basic types of line in a data file; definition instructions, execution
       instructions and comment lines. DO-CHECKS and END are the only execution
       instructions, all other instructions are definitions. The purpose of the data file is to define
       the problem and then solve it, the solution being initiated by a DO-CHECKS command.
       All definition instructions before the DO-CHECKS will be stored until required. If a
       definition is duplicated the second instruction will supersede the first. Even after a DO-
       CHECKS command all the current definitions are retained so that if another analysis is
       required, perhaps using a different solution method as in the example, then only the new
       data has to be input before the next DO-CHECKS command. The END instruction


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       terminates the run, so it is usually the last instruction in the data file; any data following an
       END instruction would be ignored.

       Comment lines are signified by either a !, # or * as the first character on the line. The
       difference between the three initial characters is; lines beginning with # and * are echoed
       in the summary file whereas those beginning with ! are only used to add comments in the
       data file. The * summary file comment generates a new summary page with headers, etc,
       therefore it is usually used at the beginning of a data file to initialise the summary file.
       Comment lines have no bearing on the course of the analysis but should be used liberally
       to annotate the data and summary file.

       These nine lines are simply comments for the data file:
                      !
                      !   APPLICATION MANUAL EXAMPLE 1
                      !   ==============================
                      !
                      !   SIMPLE STAND-ALONE CONCRETE SLAB ULTIMATE STRENGTH CHECK
                      !   USING BOTH STRIP AND LAYERED METHODS
                      !
                      !   RUN CONTROL DATA
                      !


       whereas these two comments will appear in the summary file as well:
                  #
                  # STRIP METHOD AT 90 DEGREES


       Finally the following line is used to cause a new page, including title and column
       headers to be generated in the summary file:
                  *


3.3.1 Run Initialisation Data

       The commands in the example which constitute the run initialisation data are as follows:

                  TITLE APPLICATION MANUAL EXAMPLE 1
                  CODE-CHECK ON
                  STRENGTH-CHECK ON


       The TITLE card defines the description which will be displayed on each page of output in
       the summary and list files. The description which follows the TITLE keyword can be up to
       seventy-four characters long.

       The CODE-CHECK ON card is used to control whether the actual analysis proceeds or not
       and is in effect the opposite of the DATA-CHECK-ONLY card. For some work the actual
       analysis calculations may take so long that the run has to be performed as a Batch Job. A
       CODE-CHECK OFF instruction would allow the data file to be checked for errors before
       submitting the job to the Batch Queue. CODE-CHECK or CODE-CHECK ON indicates
       that if the data checks are error free then the analysis should proceed immediately.

       In this example a ULS analysis is to be performed, therefore STRENGTH-CHECK ON
       instruction is used to initiate this form of analysis. Other forms of check that can be
       performed are SLS and FLS checks. The corresponding initiation commands are
       SERVICE-CHECK ON and FATIGUE-CHECK ON.


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3.3.2 Slab Data

       The slab geometry for the example is detailed in Figure 3.1.-1. The definition of this
       section in CONCRETE-CHECK is achieved by the following commands:
                  MATERIAL-PARTIAL-SAFETY-FACTORS 1.50 1.15 1.15                  1.25
                  CONCRETE-DEPTH 300.0
                  CONCRETE-PROPERTIES BS8110 50.0 0.2
                  REBAR-PROPERTIES 1 410.0
                  REBAR-PROPERTIES 3 400.0 190000.0
                  REINFORCEMENT-BARS 1 1 0 25.0 200.0 25.0
                  REINFORCEMENT-BARS 2 3 0 25.0 200.0 200.0
                  TOP-STEEL   REBARS 1 25.0 0.0
                  TOP-STEEL   REBARS 2 50.0 90.0
                  BOTTOM-STEEL       REBARS      2 25.0 0.0

                  BOTTOM-STEEL      REBARS     1           50.0    90.0
                  SHEAR-REINFORCEMENT   20 1 300           300



       The four values specified in the MATERIAL-PARTIAL-SAFETY-FACTORS card should
       reflect the limit state being checked, in this case the values are typical of those required for
       a ULS analysis. The CONCRETE-PROPERTIES card specifies that the concrete is
       assumed to follow the BS8110 Part1:Figure 2.1 stress-strain curve. Other possible stress-
       strain curves include DNV, PARABOLIC, LINEAR, RIGOROUS (BS8110 Part2:Figure
       2.1) and DEFINED. By default the tension part of the stress-strain curve is neglected, but
       if it were required it could be included by specifying a separate CONCRETE-
       PROPERTIES TENSION card.

3.3.3 Load Case Data

       The loading data for the example is detailed in Figure 3.1.-1. In this stand-alone run, the
       definition of the loads for CONCRETE-CHECK is achieved using the following
       commands:

                ENVELOPE-NAME MOMENT IN BOTH DIRECTIONS
                ENVELOPE MAXIMUM -0.50 -0.40 0.10 0.100 0.060 0.005 0.050 0.050
                ENVELOPE MINIMUM -0.50 -0.40 0.10 -0.100 -0.060 0.005 0.050 0.050


       The ENVELOPE-NAME simply associates a title with the current load envelopes. The
       ENVELOPE commands allow the user to define the MAXIMUM and MINIMUM values
       that each of the eight load components (NX, NY, NXY, MXX, MYY, MXY, NXZ and NYZ) can
       take. In the example, only the flexural bending moments are allowed to change sign, all
       other loads take fixed values. Any partial safety factors should have been applied to the
       loads before entering the values into the data file.

3.3.4 Summarising the Input Data

       Whilst the program can echo the input data in the output file as it reads through the data
       file, the listing produced is not easily interpreted. The input data can be summarised in a
       compact format by use of the following instruction just prior to performing the check:

                  PRINT-DATA

       If after the DO-CHECKS instruction some data is modified, a PRINT-DATA card before
       the subsequent DO-CHECKS card will output the current status of all data.


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3.3.5 Analysis Method
       As mentioned in the introduction to the second chapter, two types of analysis method can
       be used, strip method or layered method. In this example two strip method analyses are
       performed on sections at ninety degrees to each other. A single layered method analysis is
       also performed. All three analyses use the same slab data, each being actioned by a DO-
       CHECKS instruction.
                  METHOD STRIP 0 100
                  DO-CHECKS

                  METHOD STRIP 90 100
                  DO-CHECKS

                  METHOD LAYER 10 100
                  DO-CHECKS

       The first argument to the METHOD STRIP instruction is the orientation of the section. In
       the first analysis the section is normal to the X-axis, in the second parallel to the X-axis.
       The second argument is the maximum number of iterations used to ascertain the position
       of the neutral axis.

       A layered analysis checks sections through the slab at 22.5° increments, therefore no
       orientation angle is required. For METHOD LAYER the user has to specify the number of
       layers and maximum number of iterations.


3.4    OUTPUT DESCRIPTION


       Two forms of output are produced by the CONCRETE-CHECK program, summary output
       and detailed output. For this first example, all pages from both output files have been listed
       in full. Future examples will only include selected pages of output which contain particular
       results to be discussed in the text.

3.4.1 Description of Summary Output File

       The summary output file for the example is listed in Figure 3.4-1. The titles and headers
       for this page were generated by the * comment line in the input file. The listing also shows
       the three summary file comments, produced by the # comment lines. Following the
       comments the results for the corresponding limit state check are presented in a single line.
       Thus the following two lines in the data file:

                  # STRIP METHOD AT 0 DEGREES
                  DO-CHECKS


       in effect produce the following two lines in the summary file:

        STRIP METHOD AT 0 DEGREES
            0     1     0                    300.0 4      0 13.635     .00000              P


       At the beginning of each summary line is an echo of the group/set number, class, and
       node/location position number. This is followed by the slab section depth, number of rebar
       and prestress tendon layers and the rebar and shear link areas (in mm2 per mm width). The
       final item at the end of each line indicates whether the section has passed (P) or failed (F)
       the strength check. In this case the test section has passed all the strength checks.


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3.4.2 Description of Detailed Output File

       The detailed output file is listed in Figure 3.4-2. The first page is a header sheet which
       displays the version and revision number of the program.


       The next three pages are an expansion of the input data. They show how each parameter on
       an input card has been interpreted and can be useful when debugging the input data file.
       The expanded input data could have been suppressed using the LIST–INPUT–DATA OFF
       instruction.

       Pages Five and Six result from the PRINT–DATA instruction and show the current status
       of all major variables in a concise format. Note that some variables have not been set at
       this point and therefore display their default values, e.g. properties have only been
       specified for rebar material types one and three, the other eight possible types assume the
       default values:

         Young's modulus              = 200.0 Nmm-2
         yield stress                 = 410.0 Nmm-2.

       Page Seven contains an echo of more definition instructions which set up the actual
       analysis method. Once the DO–CHECKS instruction is encountered the program starts the
       analysis and a new page is started.

       Page Eight shows the results for the BS8110 Strip Method section analysis for an angle of
       0°, i.e. a plane perpendicular to the X–axis. The resolved loads show the maximum and
       minimum loads applied to the section; for this angle the loads correspond to the max/min
       values of Nx, Mx and the maximum value of Nxz. The section analysis results show the
       section ultimate hogging and sagging resistance moment capacity and the distance of the
       neutral axis from the compression face. In this case both ultimate resistance moments
       exceed the applied moments therefore the remarks column shows that the section has
       passed the check. The pass or fail status is repeated at the bottom of the table of results by
       displaying a banner across the page showing SAFE or UNSAFE respectively.

       Page Nine details the shear checks performed on the 0° section. The listing shows the
       maximum shear load, total shear resistance and whether any shear links are required in the
       section. The pass/fail status of the check is again displayed in the banner at the bottom of
       the output.

       The next three pages, Ten to Twelve, repeat the section and shear analyses for the 90°
       section. Again the ultimate resistance moment exceeds the applied moment and the total
       shear resistance is greater than the applied shear, so the 90° section passes all the ULS
       checks.

       The next set of strength checks on the slab use the layered method. The METHOD
       LAYER instruction is echoed to the output file on Page Thirteen, which also summarises
       how the parameters associated with the instruction have been interpreted. The layered
       section analysis results are listed on Page Fourteen. These show that two loading scenarios
       were analysed. The first used the maximum values of Nx, Ny, Mx & My and the minimum
       values of Nxy, and Mxy (++-++-) to produce compression in the top fibre of the slab. The
       second loading system uses the minimum values of all components (------) to produce
       compression in the bottom fibre. The listing shows that both loading schemes converged,

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Concrete Suite – Application Manual                                  Simple Stand-Alone Ultimate Limit State Checks

       the final concrete fibre strains and rebar stresses for each layer are also displayed. No
       redesign of the section has been required and the reinforcement areas listed are as supplied
       in the input file. The section has therefore passed the section check and the banner
       indicates this fact.

       The layered method shear check results for Example 1 are displayed on Page Fifteen of the
       output. Compressive axial load is beneficial to shear resistance, therefore of the two
       previous cases investigated only the most tensile is used i.e. the (++-++-) case. The layered
       method calculates the shear load and resistance for eight section angles, spaced at 22.5°
       intervals and determines the worst section angle. In this example, the worst section angle is
       22.5° to the X-axis. The section shear resistance is evaluated using the BS8110 method
       (the default); if it is less than the shear load the program calculates the required area of
       shear steel. In this case no shear steel is required, therefore the sections passes the shear
       code check.

       Page Sixteen of the output is simply a data echo of the END instruction and concludes the
       output listing.




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                     Figure 3.1.-1 Test Section - Showing Assumed Loads



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          Layer              Properties              Diameter               Spacing 1              Spacing 2
                                                      (mm)                    (mm)                   (mm)

      1                        Type 1                    25                     200                     25
      2                        Type 3                    25                     200                     200
      3                        Type 3                    25                     200                     200

      4                        Type 1                    25                     200                     25




                           Rebar Type                 Yield            Youngs Modulus
                                  1                   410.0                 200000.0
                                  3                   400.0                 190000.0




                         Figure 3.3-1 Dimensions and Material Properties


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                                                                                                              Figure 3.4-1 Summary Output File




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                                                                                                          Figure 3.4-2 Detailed Output File




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                                                                                                                  Figure 3.4-2 (Cont.) Detailed Output File




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                                                                                                                Figure 3.4-2 (Cont.) Detailed Output File




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                                                                                                                      Figure 3.4-2 (Cont.) Detailed Output File




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                                                                                                                      Figure 3.4-2 (Cont.) Detailed Output File




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Concrete Suite – Application Manual                                                                     Advanced Features




4     ADVANCED FEATURES


4.1    INTRODUCTION

       The purpose of this chapter is to expand the scope of the checks performed, introduce the
       redesign facility and demonstrate how the user can increase the efficiency of data input.

       The first modification is to add prestressing tendons to the reinforced slab section and
       rerun a ULS check. The concepts of primary and secondary prestress are introduced at this
       point.

       In addition to its analysis capabilities CONCRETE-CHECK can function as a design tool.
       The loadings for the second run are increased so that the initial section design fails to meet
       the ULS requirements; the run continues with the redesign option invoked so that a section
       which meets the requirements is output.

       To date all input data has been put in a single data file. When checking a large structure,
       some of the data will be common to all runs (for example there will only be a limited set
       of rebar types used). CONCRETE-CHECK allows the user to group the general data in a
       separate file which can then be referenced from the main data file for each analysis.

       All the checks so far have concentrated on a single location. The final run introduces the
       facilities for checking multiple locations around a slab. At this point the rudimentary
       plotting facilities are described.


4.2    PRESTRESS DATA


       The input data file for Example 2 is listed below:




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4.2.1 Definition of Prestress Tendon Data

       The assumed slab cross-section, which now includes prestress tendons is shown in Figure
       4.2-1. To define the tendon properties and position the following lines are required:

                  TENDON-PROPERTIES 3  1500.0 195000.0   0.005
                  PRESTRESS-TENDONS 1 3 0 10 25.0   1500.0   1.0
                  BOTTOM-STEEL TENDONS 1 50.0 0.0


       The tendons are orientated along the X-axis, spaced 1.5m apart and 0.1m below mid-depth.
       The tensile load in one tendon is 1.0 MN, which generates the following loads per unit
       width on the section:


                  NX        =   -1.0/1.5                = -0.667 MNm-1              (compressive)
                  NY        =   0.0 MNm-1
                  NXY       =   0.0 MNm-1
                  MX        =   1.0*(-0.1)/1.5          = -0.0667 MN                (hogging)
                  MY        =   0.0 MN
                  MXY       =   0.0 MN

       Note that in the PRESTRESS-TENDONS card the S-N curve number has been set to zero
       because no FLS checks are being performed.

       Prestress loads on a particular slab can be divided into two categories:

              − primary prestress loads due to local prestress tendons;

              − secondary prestress loads due to loadings transmitted from other parts of the
                  structure.

       The main difference between the two is that the primary (tendon) loads are required to be
       strain compatible with the local concrete, whereas secondary loads are invariant of the
       local strain field. The primary prestress load is defined by the last parameter on the
       PRESTRESS-TENDON card as 1.0 MN and has been expanded into loads per unit width
       above. The secondary prestress is defined in the PRESTRESS-LOADS card:




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                   PRESTRESS-LOADS SECONDARY DIRECT 0.050 0.025 0.05 0.001 0.002 -0.0007 0.0 0.0

       The summation of primary and secondary prestress is termed total ptestress. Thus the total
       prestress loads for Example 2 are as follows:

                                                                        M
                                    Nx        Ny         Nxy                x       My            Mxy
             Primary              -0.667      0.000      0.000         -0.0667      0.000        0.0000
             Secondary             0.050      0.025      0.050          0.0010      0.002       -0.0007
             TOTAL                -0.617      0.025      0.050         -0.0657      0.002       -0.0007


       The SECONDARY option indicates that the eight loadings defined here are simply added
       to the primary prestress load defined in the PRESTRESS-TENDONS card; the alternative
       option TOTAL would be used where the secondary load has to be computed as the
       difference between the given loading and the primary prestress.

       The DIRECT option indicates that for this example the eight loadings are included with
       the command; the alternative options are ANALYSIS and RECOVER to obtain the loads
       from an FE analysis or CONCRETE-ENVELOPE backing files respectively.

4.2.2 Discussion of Results

       The summary output for this run is produced in Figure 4.2-2. The first thing to observe is
       that the pass/fail flag is now showing that the section failed the check.

       To see what caused the section to fail, we need to look at page nine of the detailed listing,
       see Figure 4.2-3, which shows that the layered solution for the section is diverging
       because the section cannot resist the applied direct loads and moment. Thus, assuming the
       analysis is at the design phase, the section must be redesigned. CONCRETE-CHECK can
       be set up to redesign the section by incrementing the size of rebars, this is demonstrated in
       section 4.3.

       Note that because the section has failed no shear results have been calculated and the
       detailed listing also clearly indicates failure by displaying the following banner across the
       page:
       ********************************************************
       UNSAFE      UNSAFE    UNSAFE    UNSAFE    UNSAFE    UNSAFE
       ********************************************************


4.3    SLAB SECTION REDESIGN FUNCTION


       The redesign facility is invoked by the following instruction:
                  REDESIGN 10




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          which allows the program to redesign the slab cross-section by incrementing the area of
          all rebars which have a non-zero TOP/BOTTOM-STEEL resize parameter. In the above
          instruction up to ten iterations are allowed.

          The section in Example 2 failed to meet the limit state requirement, so the problem was
          rerun with the above REDESIGN instruction. To allow the rebars to be resized the
          TOP/BOTTOM STEEL instructions have been modified as follows:


                    TOP-STEEL             REBARS   1   25.0 0   0.25
                    TOP-STEEL             REBARS   1   50.090   0.25
                    BOTTOM-STEEL          REBARS   1   50.090   0.25
                    BOTTOM-STEEL          REBARS   1   25.090   0.25

          The output from the redesign run is shown in Figures 4.3-1 and 4.3-2. The summary
          output shows that the section has successfully been redesigned, with a required total rebar
          area of 9.35mm2 per mm. The detailed listing shows that three iterations were required
          before the section passed the check. After the iterations, with a 25% increase in area per
          iteration, each rebar area had increased to (1.25)3 = 1.953 times the original area. Now that
          the section passes the check, the shear check is also performed using the redesigned
          section and is also satisfactory.


4.4       USE OF MULTIPLE INPUT FILES (SEE NOTE 1)


          When analysing large structures, some data will be common to all runs, for example
          material properties. CONCRETE-CHECK allows the user to segregate data into several
          input files, the next file being referenced from the current input file by a CHANGE-
          INPUT-STREAM card. This instruction switches the program from reading data on the
          default input stream 5, to the stream number specified on the card. To avoid clashes with
          other default input/output streams, it is recommended that numbers in the range 54 to 99
          are used. As well as specifying a stream number within the program, the user must make
          the link between the file and the input stream for the operating system before running the
          program. The commands to achieve this are detailed in Section 3.0 of the User Manual.

          To demonstrate the multiple file capability, the previous example will be split into three
          files; the root data file containing the run control data and required strength checks, a slab
          definition file to define the material properties and dimensions on input stream 54 and
          finally a loading data file on stream 55. The file logic is shown diagrammatically in Figure
          4.4-1. The root data file EXAMPLE2.DAT might comprise the following instructions:

                    !
                    !   APPLICATION MANUAL EXAMPLE 2
                    !   ===========================
                    !
                    !   SIMPLE REINFORCED/PRESTRESSED CONCRETE SLAB
                    !   ULTIMATE STRENGTH CHECK USING LAYERED METHOD
                    !   AND DEMONSTRATING MULTIPLE FILE CAPABILITY




      1
           Not all operating systems allow the use of the CHANGE-INPUT-STREAM command, check under the relevant operating system
           in Section 3.0 of the User Manual.




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                  !
                  !
                  ! RUN CONTROL DATA
                  !
                  ! TITLE APPLICATION MANUAL EXAMPLE 2
                  *
                  ANALYSE-NODE-CLASSES 1
                  CODE-CHECK ON
                  !
                  ! SWITCH TO INPUT STREAM 54 FOR SLAB DATA
                  !
                  CHANGE-INPUT-STREAM 54
                  !
                  ! RETURN POINT FROM LOAD DATA FILE
                  !
                  ! SELECT STRENGTH CHECKS, SET LAYERED METHOD PARAMETERS
                  !
                  STRENGTH-CHECK ON
                  METHOD LAYER 10 500 0.02 10
                  !
                  ! SWITCH REDESIGN FACILITY ON AND ECHO DATA
                  !
                  REDESIGN 10
                  PRINT-DATA
                  !
                  ! PERFORM STRENGTH CHECKS
                  !
                  DO-CHECKS
                  END


       The slab material properties and dimensions would then be defined in the file SLAB.DAT
       which must be assigned to input stream 54.

                  !
                  ! SECOND INPUT FILE TO DEFINE THE SLAB DATA
                  ! THIS FILE SHOULD BE ASSIGNED TO INPUT STREAM 54
                  !
                  MATERIAL-PARTIAL-SAFETY-FACTORS 1.50 1.15 1.15 1.25
                  CONCRETE-DEPTH 300.0
                  CONCRETE-PROPERTIES BS8110 50.0 0.2
                  REBAR-PROPERTIES       1 410.0
                  REBAR-PROPERTIES       3 400.0    190000.0
                  REINFORCEMENT-BARS 1 1 0 20.0 500.0 25.0
                  REINFORCEMENT-BARS 2 3 0 25.0 200.0 200.0
                  TOP-STEEL      REBARS 1 25.0 0.0
                  TOP-STEEL      REBARS 1 50.0 90.0
                  BOTTOM-STEEL   REBARS   1 50.0 90.0
                  BOTTOM-STEEL   REBARS   1 25.0 0.0
                  TENDON-PROPERTIES 3 1500.0 195000.0 0.005
                  PRESTRESS-TENDONS 1 3 0 10 25.0 1500.0 1.0
                  BOTTOM-STEEL TENDONS 1 50.0 0.0
                  SHEAR-REINFORCEMENT 20 1 300 300
                  !
                  ! SWITCH TO STREAM 55 TO INPUT LOAD DATA
                  !
                  CHANGE-INPUT-STREAM 55

       Finally the load data would be defined in the following file LOAD.DAT, which must be
       assigned to input stream 55. Note that this file returns to the initial input stream at the
       end, so that the last half of the root file can be read in.

          !
          ! PROVIDE LOAD DATA AND SECONDARY PRESTRESS DATA
          !
          ENVELOPE-NAME SINGLE LOAD CASE WITH PRESTRESS
          ENVELOPE MAXIMUM -1.00 -0.50 0.30 0.40 0.22 0.0002 0.050 0.050
          ENVELOPE MINIMUM -1.00 -0.50 0.30 0.40 0.22 0.0002 0.050 0.050
          PRESTRESS-LOADS SECONDARY DIRECT 0.050 0.025 0.05 0.001 0.002 -0.0007 0.0 0.0
          !
          ! RETURN TO PRIMARY INPUT FILE FOR ANALYSIS COMMANDS
          !
          CHANGE-INPUT-STREAM



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       The additional input files have to be associated to input streams 54 and 55 using operating
       system commands, see the User Manual for more details. For programs running under
       VMS, this is achieved by adding the following lines in the command file used to initiate
       the program:

                  ASSIGN/USER_MODE SLAB.DAT FOR054
                  ASSIGN/USER_MODE LOAD.DAT FOR055


4.5    ANALYSIS OF MULTIPLE LOCATIONS


       So far the checks have concentrated on one location. In general, a large number of
       locations around the structure will be checked, therefore the program includes
       powerful facilities for classifying locations. Using Example 3 the basics of specifying
       multiple locations will be introduced. The capacity to analyse multiple locations is
       especially important when the program is used in conjunction with FE models, and
       data is available for a large number of points. Thus a detailed explanation of location
       selection will be included in Chapter 8, when more realistic examples can be
       incorporated.

4.5.1 Data File for Example 3

       The data file for example 3 comprises the following instructions:

                  !
                  ! APPLICATION MANUAL EXAMPLE 3
                  ! = = = = = = = = = = = = = = = = = = = = =
                  !
                  ! SIMPLE CONCRETE SLAB ULTIMATE STRENGTH CHECK SHOWING USE
                  ! OF BEGIN-PLOT AND FINISH-PLOT TO CONTROL PLOTTING
                  !
                  ! RUN CONTROL DATA
                  !
                  TITLE APPLICATION MANUAL EXAMPLE 3
                  *
                  ANALYSE-NODE-CLASSES 4
                  GROUP 1
                  CODE-CHECK ON
                  !
                  ! PROVIDE SLAB DATA
                  !
                  MATERIAL-PARTIAL-SAFETY-FACTORS       1.50 1.15 1.15 1.25
                  CONCRETE-DEPTH 300.0
                  CONCRETE-PROPERTIES BS8110 50.0 0.2
                  REBAR-PROPERTIES 1 410.0
                  REBAR-PROPERTIES 3 400.0 190000.0
                  REINFORCEMENT-BARS 1 1 0 25.0 200.0 25.0
                  REINFORCEMENT-BARS 2 3 0 25.0 200.0 200.0
                  TOP-STEEL          REBARS 1 25.0 0.0 0.25
                  TOP-STEEL          REBARS 2 50.0 90.0 0.25
                  BOTTOM-STEEL REBARS 2 25.0 0.0 0.25
                  BOTTOM-STEEL REBARS 1 50.0 90.0 0.25
                  SHEAR-REINFORCEMENT 20 1 300 300
                  !
                  ! SELECT LAYERED METHOD, STRENGTH CHECKS, REDESIGN AND ECHO INPUT DATA
                  !
                  METHOD LAYER 10 1000 0.02
                  STRENGTH-CHECK ON
                  REDESIGN 10
                  PRINT-DATA
                  !
                  ! PERFORM CHECKS AT SIX LOCATIONS AROUND SECTION, CHANGING LOADS EACH TIME


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Concrete Suite – Application Manual                                                                     Advanced Features
                  !
                  BEGIN-PLOT
                  SECTION 1 LIST 0.0
                  ENVELOPE-NAME LOADS AT LOCATION        1
                  ENVELOPE MAXIMUM -0.50 -0.40           0.100     0.100 0.060 0.005           0.150 0.050
                  ENVELOPE MINIMUM      -0.50 -0.40       0.100     0.100 0.060 0.005           0.150 0.050
                  DO-CHECKS
                  SECTION 1 LIST 2.0
                  ENVELOPE-NAME LOADS AT LOCATION        2
                  ENVELOPE MAXIMUM -0.60 -0.45           0.110     0.200 0.080 0.006           0.255 0.060
                  ENVELOPE MINIMUM      -0.60 -0.45       0.110     0.200 0.080 0.006           0.255 0.060
                  DO-CHECKS
                  SECTION 1 LIST 2.0
                  ENVELOPE-NAME LOADS AT LOCATION 3

                  ENVELOPE MAXIMUM -0.70 -0.50 0.120              0.300 0.100 0.007          0.360 0.080
                  ENVELOPE MINIMUM -0.70 -0.50 0.120               0.300 0.100 0.007          0.360 0.080
                  DO-CHECKS
                  SECTION 1 LIST 3.0
                  ENVELOPE-NAME LOADS AT LOCATION 4
                  ENVELOPE MAXIMUM -0.50 -0.55 0.130              0.400 0.120 0.008          0.465 0.100
                  ENVELOPE MINIMUM -0.50 -0.55 0.130               0.400 0.120 0.008          0.465 0.100
                  DO-CHECKS
                  SECTION 1 LIST 4.0
                  ENVELOPE-NAME LOADS AT LOCATION 5
                  ENVELOPE MAXIMUM -0.50 -0.60 0.140              0.500 0.140 0.009          0.570 0.120
                  ENVELOPE MINIMUM -0.50 -0.60 0.140               0.500 0.140 0.009          0.570 0.120
                  DO-CHECKS
                  FINISH-PLOT
                  !
                  END

      In this simple example the SECTION instruction is merely used to associate the results
      produced by the next DO-CHECKS instruction with a location. In total, five locations are
      created. At each location a new loading is defined and the slab section analysed. The
      loadings are increased at each location, so that although the first two locations pass the
      ULS check the other three have to be redesigned with larger rebar area before they pass
      the check.

4.5.2 Plotting Facility

      Example 3 also provides an introduction to the limited plot data facilities available in
      CONCRETE-CHECK. This facility is only available when the SECTION command is
      used to specify code check locations, i.e. when class 4 locations are being checked. The
      main use for the plot file is for processing by the PLOTIT program, although the data can
      also be incorporated into user written programs and spreadsheets.

      Two commands are used to control the output, BEGIN-PLOT commences the transfer of
      data to the output file and FINISH-PLOT terminates the transfer. A transfer of plot data
      occurs whenever a DO-CHECKS instruction is encountered. The information transferred
      depends on the type of checks being performed, currently the following results can be
      output by this method:

                 ULS        -      Total Main Steel Areas
                 ULS        -      Link Steel Areas
                 SLS        -      Maximum Crack Width
                 SLS        -      Maximum Rebar Stress
                 FLS        -      Concrete Fatigue Life
                 FLS        -      Minimum Tendon Fatigue Life
                 FLS        -      Minimum Tendon Fatigue Life

      Example 3 only performs a ULS analysis, therefore only the total main steel area and link
      steel area will be output. When the plot facility is used, a file should be assigned to unit 53

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Concrete Suite – Application Manual                                                                     Advanced Features
       to receive the result data. Assigning files to data streams is covered in Chapter 3 of the
       CONCRETE-CHECK User Manual.

       The output produced by the plot instructions incorporated into Example 3 is shown in
       Figure 4.5-1. The file contains the values for the required total steel area at each section
       location considered in the run. In addition the file includes data labels to identify what
       results are contained in the file.




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       Concrete Suite – Application Manual                                                                     Advanced Feature




0.3m




       NOTE: REINFORCEMENT          AS PER EXAMPLE 1




              Figure 4.2-1 Section For Example 2 Showing Prestress Tendons



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Concrete Suite – Application Manual                                                                     Advanced Features




                                                                                                                    Figure 4.2-2 Summary Output File – Example 2




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Concrete Suite – Application Manual                                                                     Advanced Features




                                                                                                                     Figure 4.2-3 ULS Section Analysis Results – Example 2




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Concrete Suite – Application Manual                                                                     Advanced Features




                                                                                                               Figure 4.3-1 Summary Output File (After Redesign) – Example 2




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Concrete Suite – Application Manual                                                                     Advanced Features




                                                                                                               Figure 4.3-2 Redesigned Section Analysis Results – Example 2




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Concrete Suite – Application Manual                                                                     Advanced Features




                                                                                                                       Figure 4.3-2 (Cont.) Redesigned Section Analysis Results – Example 2




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Concrete Suite – Application Manual                                                                     Advanced Features




             Figure 4.4-1 Diagrammatic Representation Of CHANGE-INPUT-STREAM
                                   Commands For Example 2




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Concrete Suite – Application Manual                                                                     Advanced Features




HEADING
RESULT T YPE : ULS REIN FORCEMENT AREA (MM2/MM)
FIGURE
SECTION      1
SURFACE LONG
SMOOTHX
4.5.2.1. 1.1 LABELX
LOCATION AROU N D SECTIO N (DEG)
LABELY
ULS REIN FORCE M ENT AREA (MM2/MM)
DATASET
     .00000E+ 00      .13635E+02
     .10000E+ 01      .13635E+02
     .20000E+ 01      .17044E+02
     .30000E+ 01      .26632E+02
     .40000E+ 01      .33290E+02
LINE
XZERO
END




                    Figure 4.5-1 Data Resulting From Plot Output Facilities




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Concrete Suite – Application Manual                                                 Serviceability Limit State Checks



5     SERVICEABILITY LIMIT STATE CHECKS


5.1    INTRODUCTION

       The purpose of this chapter is to demonstrate the serviceability limit state (SLS) checking
       facilities of CONCRETE-CHECK. Limit states of serviceability include:

                 − Deflection
                 − Cracking

       The deflection of the structure can be obtained from other analysis methods, for example
       FE analysis, for direct evaluation by the designer. The main SLS considered by
       CONCRETE-CHECK is crack width, which is evaluated and compared to a user specified
       limit. No permanent damage should occur in service, so the user is also expected to supply
       a working limit for rebar stresses.

       Using Example 4 the text discusses the difference between an SLS and a ULS input data
       file and introduces those commands specific to this type of analysis.


5.2    SLS EXAMPLE PROBLEM


       The input data file for Example 4 contains the following instructions:

                 !
                 ! APPLICATION MANUAL EXAMPLE 4
                 !
                 ! SIMPLE REINFORCED/PRESTRESSED CONCRETE SLAB
                 ! SERVICEABILITY LIMIT STATE CHECKS USING STRIP AND LAYERED METHOD
                 !
                 ! RUN CONTROL DATA
                 !
                 TITLE APPLICATION MANUAL EXAMPLE 4
                 *
                 ANALYSE-NODE-CLASSES 1
                 CODE-CHECK ON
                 !
                 ! PROVIDE SLAB DATA
                 !
                 MATERIAL-PARTIAL-SAFETY-FACTORS 1.00 1.00 1.00 1.00
                 CONCRETE-DEPTH 300.0
                 CONCRETE-PROPERTIES BS8110 50.0 0.2
                 REBAR-PROPERTIES 1 410.0
                 REBAR-PROPERTIES 3 400.0 190000.0
                 REINFORCEMENT-BARS 1 1 0 20.0 500.0 25.0
                 REINFORCEMENT-BARS 2 3 0 25.0 200.0 200.0
                 TOP-STEEL    REBARS 1 25.0 0.0 0.25
                 TOP-STEEL    REBARS 1 50.0 90.0 0.25
                 BOTTOM-STEEL REBARS 1 50.0 90.0 0.25
                 BOTTOM-STEEL REBARS 1 25.0 0.0 0.25
                 TENDON-PROPERTIES 3 1500.0 195000.0 0.005
                 PRESTRESS-ENDONS 1 3 0 10 25.0 1500.0 1.0
                 BOTTOM-STEEL TENDONS 1 50.0 0.0
                 SHEAR-REINFORCEMENT 20 1 300 300
                 COMPRESSION-STEEL INEFFECTIVE
                 !
                 ! PROVIDE LOAD AND SECONDARY PRESTRESS DATA
                 !
                 ENVELOPE-NAME SIGNED MOMENT WITH PRESTRESS
                 ENVELOPE MAXIMUM 0.30 -0.100 0.1 0.30 0.12       0.0002
                 ENVELOPE MINIMUM 0.30 -0.100 0.1 0.30 0.12       0.0002


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Concrete Suite – Application Manual                                                 Serviceability Limit State Checks
                 PRESTRESS-LOADS SECONDARY DIRECT 0.05 0.025 0.05 0.001 0.002 -0.0007
                 !
                 ! SET STRIP METHOD, ECHO DATA AND PERFORM SERVICE CHECKS AT 0 AND 90 DEGREES
                 !
                 SERVICE-CHECK ON
                 SERVICE-CRITERIA 0.25 140.0
                  METHOD STRIP 0.0
                  PRINT-DATA
                  DO-CHECKS
                  METHOD STRIP 90.0
                  DO-CHECKS
                  !
                  ! SET LAYERED METHOD PARAMETERS, ECHO DATA AND PERFORM SERVICE CHECKS
                  !
                  METHOD LAYER 10 500 0.02 10
                  PRINT-DATA
                  DO-CHECKS
                  END



5.3    SLS SPECIFIC INSTRUCTIONS


       The following commands are specific to an SLS analysis:

                  SERVICE-CHECK ON
                  SERVICE-CRITERIA 0.25 140.0


       SERVICE-CHECK ON indicates that an SLS analysis is to be performed at the next DO-
       CHECKS instruction, it is the SLS equivalent of the ULS command STRENGTH-
       CHECK ON. At this point in the manual the various limit state checks are being
       introduced in independent examples, but it should be noted that the program does allow
       the user to perform several types of check in one run.

       The SERVICE-CRITERIA instruction allows the user to define the maximum allowable
       crack width and the rebar stress at which permanent damage occurs.

       The material partial safety factors need to be modified from those used in the ULS runs,
       typically for an SLS analysis all factors take a value of 1.0. Only biaxial in plane loads
       have been specified because it is not necessary to perform shear checks.


5.4    RESULTS FROM SLS CHECK


       The summary results file produced by Example 4 is shown in Figure 5.3-1. It shows that
       all three checks failed to satisfy the user specified criteria. The strip theory results show
       that both sections are stressed beyond the user specified point of permanent deformation
       (140 Nmm-2 in this case), and the crack width for the 90° section also exceeds the user
       specified maximum of 0.25 mm. The results from the layered method show that it too
       produced stresses in the rebars and crack widths greater than the maximum allowable
       values. The detailed listings for each check are produced in Figure 5.3-2.




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Concrete Suite – Application Manual                                                 Serviceability Limit State Checks




                                                                                                                        Figure 5.3-1 Summary Output File – Example 4




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                                                                                                                        Figure 5.3-2 Summary Output File – Example 4




                                                           0




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Concrete Suite – Application Manual                                                 Serviceability Limit State Checks




                                                                                                                        Figure 5.3-2 (Cont.) Summary Output File – Example 4




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Concrete Suite – Application Manual                                                 Serviceability Limit State Checks




                                                                                                                        Figure 5.3-2 (Cont.) Summary Output File – Example 4




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




6     FATIGUE LIMIT STATE CHECK


6.1    INTRODUCTION

       This section describes the use of a deterministic approach to evaluating the cumulative
       damage and fatigue life of both concrete and reinforcing steel components in a structure
       subjected to cyclic loading. As explained in the Theoretical Manual, the major advantage of
       this approach is that it can consider the non-linearity in stress response of the structure with
       respect to wave height (resulting from the non-linear dynamic response of the structure).

       Example 5 is designed to demonstrate FLS checks on a reinforced/prestressed concrete slab
       using both the layered and strip methods.


6.2    FLS EXAMPLE PROBLEM


       The input data file for Example 5 contains the following instructions:
                !
                ! APPLICATION MANUAL EXAMPLE 5
                ! = = = = = = = = = = = = = = = = = = = = =
                ! EXAMPLE TO DEMONSTRATE FATIGUE LIMIT STATE CHECKS
                ! USING THE LAYERED AND STRIP METHODS.
                !
                ! RUN CONTROL DATA
                !
                TITLE APPLICATION MANUAL EXAMPLE 5 (FLS CHECKS)
                *
                ANALYSE-NODE-CLASSES 1
                CODE-CHECK ON
                UNITS 1.0 10.0
                !
                ! SLAB GEOMETRY
                !
                MATERIAL-PARTIAL-SAFETY-FACTORS 1.30       1.0   1.0   1.0
                CONCRETE-DEPTH 1050.0
                CONCRETE-PROPERTIES BS8110     60.0     0.2
                REBAR-PROPERTIES       1 400.0
                REINFORCEMENT-BARS     1 1 1    20.0      170.0 20.0
                REINFORCEMENT-BARS     2 1 1    20.0      75.0    20.0
                REINFORCEMENT-BARS     3 1 1    20.0      190.0 20.0
                TOP-STEEL      REBARS 2    75.0 0.0       0.10
                TOP-STEEL      REBARS 3    95.0 90.0      0.10
                TOP-STEEL      REBARS 3    115.0 90.0     0.10
                BOTTOM-STEEL   REBARS 3    115.0 90.0     0.10
                BOTTOM-STEEL   REBARS 3    95.0 90.0      0.10
                BOTTOM-STEEL   REBARS 1    75.0 0.0       0.10
                TENDON-PROPERTIES      1         1755.0     195000.0   0.005
                PRESTRESS-TENDONS      1         1    1    12   13   420.0   1.43351
                TOP-STEEL TENDON       1         140.0     90.0
                BOTTOM-STEEL TENDON    1         140.0     90.0
                !
                ! FATIGUE DATA
                !
                FATIGUE-CHECK ON
                FATIGUE-LIFE 60.0
                CONCRETE-S-N-CURVE 10.0 8.0
                STEEL-S-N-CURVE 1 400 10177.5 6.0 235 251773.5 2.8 65 8831122.1                           4.8
                !
                ! ANALYSE USING STEPPED WAVE
                !      1 - STRIP METHOD 0 DEGREES
                !      2 - STRIP METHOD 90 DEGREES
                !



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                COMBINATION 1 DIRECT           4.0    4.0     -0.4    0.0     -0.30 0.03 0.0   0.0
                COMBINATION 2 DIRECT           3.0    6.0     -1.0    -0.4    -0.36 0.06 0.0   0.0
                COMBINATION 3 DIRECT           0.0    4.0     -1.0    -1.6    -0.42 0.15 0.0   0.0
                COMBINATION 4 DIRECT           -3.0 1.0       -0.4    -0.4    -0.36 0.15 0.0   0.0
                COMBINATION 5 DIRECT           -3.0 -1.0      0.0     0.0     -0.30 0.10 0.0   0.0
                COMBINATION 6 DIRECT           0.0    -1.0    1.0     0.4     -0.21 0.05 0.0   0.0
                COMBINATION 7 DIRECT           3.0    1.0     0.0     0.4     -0.21 0.00 0.0   0.0
                STATIC-COMBINATION DIRECT -5.0 -4.0           0.8     0.3     0.15 0.06  0.0   0.0
                FATIGUE-CYCLE 500000.0 STEPPED       1    2    3    4     5    6    7
                METHOD STRIP 0.0
                PRINT-DATA
                DO-CHECKS
                METHOD STRIP 90.0
                PRINT-DATA
                DO-CHECKS
                !
                ! CHANGE TO LAYERED METHOD OF ANALYSIS
                !
                METHOD LAYER 10 200
                !
                ! ANALYSE USING COMPLEX WAVE
                !
                FATIGUE-RESET
                COMBINATION 11 DIRECT 0.2             2.0 0.0 0.4 0.30 0.06 0.0 0.0
                COMBINATION 12 DIRECT 3.8             0.0 -0.8 0.0 0.00 0.00 0.0 0.0
                COMBINATION 13 DIRECT 0.0             4.0 0.8 -0.4 0.12 0.03 0.0 0.0
                FATIGUE-CYCLE     500000.0 COMPLEX 7 11 12 13
                PRINT-DATA
                DO-CHECKS
                !
                ! SIMULATE ABOVE COMPLEX ANALYSIS USING A SEVEN ELEMENT STEPPED ANALYSIS
                !
                FATIGUE-RESET
                COMBINATION 1    DIRECT      4.000 2.000      -0.800 0.400 0.300 0.060      0.0   0.0
                COMBINATION 2    DIRECT      2.569 5.127        0.127 0.087 0.394 0.083     0.0   0.0
                COMBINATION 3    DIRECT     -0.646 5.900        0.958 0.010 0.417 0.089     0.0   0.0
                COMBINATION 4    DIRECT     -3.224 3.736        1.068 0.226 0.352 0.073     0.0   0.0
                COMBINATION 5    DIRECT     -3.224 0.264        0.374 0.574 0.248 0.047     0.0   0.0
                COMBINATION 6    DIRECT      –0.646 -1.900     -0.602 0.790 0.183 0.031     0.0   0.0
                COMBINATION 7    DIRECT      2.569 –1.127      -1.124 0.713 0.206 0.037     0.0   0.0
                FATIGUE-CYCLE    500000.0 STEPPED       1 2 3       4    5 6 7
                DO-CHECKS
                STOP




6.3    FLS SPECIFIC INSTRUCTIONS


6.3.1 Initialisation Instructions

       The following instructions are used to setup the FLS check:
                FATIGUE-CHECK ON
                FATIGUE-LIFE 60.0
                CONCRETE-S-N-CURVE 10.0 8.0
                STEEL-S-N-CURVE 1 400 10177.5 6.0 235 251773.5 2.8 65 8831122.1 4.8

       FATIGUE-CHECK ON indicates that an FLS analysis is required at the next DO-
       CHECKS instruction, as opposed to a STRENGTH-CHECK or SERVICE-CHECK. The
       output from the check will be an expected life for the structure, in years. To allow the
       program to decide whether this value is acceptable the user needs to specify a design life
       (in years) as a parameter to the FATIGUE-LIFE instruction, in this example sixty years.

       The program also needs information on the number of cycles to failure at each of a range
       of stress magnitudes, i.e. an S-N curve, for all materials in the structure. A multi-linear
       log(S)-log(N) curve is assumed for each type of steel. A data set stressn, cyclesn, slopen is
       required to define the linear portion of the curve, where:

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Concrete Suite – Application Manual                                                                 Fatigue Limit State Check


                  stressn             - is the stress at one point on the nth line segment;
                  cyclesn             - is the number of cycles to failure at stressn;
                  slopen              - is the slope of the line (log(S)/log(N)) through the point.

       Up to three linear segments may be defined for the steel S-N curve.

       For concrete, two S-N curves are required, one for compression-compression cycling the
       other for tension-compression cycles. Both are assumed to be linear S-log(N), so only the
       gradients ccfact and ccfact are required. The changeover point for the two S-N curves is
       dependent on the mean stress level in the concrete, therefore a series of S-N curves result,
       depending on S (the mean stress level), see the Theoretical Manual for further details.

       The concrete S-N curves and the tri-linear S-N curve for Type 1 steel defined in the
       Example 5 data file are shown in Figure 6.3-1.

       Each rebar and tendon definition must reference a valid S-N curve, therefore the following
       instructions all reference steel S-N curve 1 via the third numerical parameter.
                REINFORCEMENT-BARS        1 1    1 20.0 170.0 20.0
                REINFORCEMENT-BARS        2 1    1 20.0 75.0   20.0
                REINFORCEMENT-BARS        3 1    1 20.0 190.0 20.0
                PRESTRESS-TENDONS        1 1 1   12 13 420.0 1.43351


6.3.2 Load Combination Data

       Example 5 demonstrates both possible methods for defining the cyclic loading. The first is
       a time history definition, using the STEPPED option, the second, a harmonic definition
       using the COMPLEX option.

       For the time history approach the loading on the slab has been defined at seven distinct
       points using the following COMBINATION instructions:

                 COMBINATION     1 DIRECT           4.0    4.0   -0.4     0.0 -0.30   0.03    0.0   0.0
                 COMBINATION     2 DIRECT           3.0    6.0   -1.0    -0.4 -0.36   0.06    0.0   0.0
                 COMBINATION     3 DIRECT           0.0    4.0   -1.0    -1.6 -0.42   0.15    0.0   0.0
                 COMBINATION     4 DIRECT          -3.0    1.0   -0.4    -0.4 -0.36   0.15    0.0   0.0
                 COMBINATION     5 DIRECT          -3.0   -1.0    0.0     0.0 -0.30   0.10    0.0   0.0
                 COMBINATION     6 DIRECT           0.0   -1.0    1.0     0.4 -0.21   0.05    0.0   0.0
                 COMBINATION     7 DIRECT           3.0    1.0    0.0     0.4 -0.21   0.00    0.0   0.0

       Each COMBINATION card assigns a reference number to a set of loading data. In the
       example the data is input DIRECTly and is therefore followed by eight load values. Other
       possible options are ANALYSIS when the data is to be recovered from an FE run, and
       NONE to specify a null loading (all zero). The program allows up to two hundred and fifty
       combinations to be specified simultaneously.

       A general static loading, which will be added to each combination in turn, has been
       defined by using the following instruction:

                  STATIC-COMBINATION DIRECT            -5.0       -4.0     0.8               0.3    0.15    0.06 0.0 0.0




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Concrete Suite – Application Manual                                                             Fatigue Limit State Check



       Again the loading is specified DIRECTly, i.e within the instruction line. The actual cyclic
       loading is defined by the FATIGUE-CYCLE command as follows:

                FATIGUE-CYCLE 500000.0 STEPPED 1 2 3 4 5 6 7


       The first parameter specifies that five hundred thousand occurrences of this cycle are
       expected in one year. The STEPPED option indicates that the cycle is being defined by a
       sequence of load combinations (or time history), in this case the seven combinations
       above. The static combination plus one load combination at a time is applied to the
       structure. At every loading step the extreme concrete fibre stresses and each rebar strain
       (which is later converted to a stress) are evaluated. For any location, the maximum and
       minimum stress values through the cycle specify the stress range and using the S-N curves
       this can be related to an amount of damage per cycle. Multiplying the damage per cycle by
       the annual number of occurrences gives the damage per year for that particular item.
       Multiple FATIGUE-CYCLEs can be defined, the annual damage being summated. Finally
       inverting the total annual damage produces the calculated fatigue life in years for the
       particular location.

       After a fatigue analysis has been completed, the fatigue cycle information must be reset
       before commencing another analysis as part of the same data file. This is achieved using
       the following instruction:

              FATIGUE-RESET

       Note: The FATIGUE-RESET command does not reset or alter the COMBINATION data,
       only the FATIGUE-CYCLE data.

       The COMPLEX approach is slightly different in that the loading throughout the cycle is
       defined by the summation of three harmonic components; static, real (0° phase) and
       imaginary (90° phase) components. This is best explained by reference to Example 5. The
       static, real and imaginary components are defined as load combinations 11 to 13 and
       associated as a COMPLEX fatigue cycle by the following instructions:
                  COMBINATION 11 DIRECT       0.2            2.0 0.0       0.4    0.30   0.06      0.0   0.0
                  COMBINATION 12 DIRECT       3.8            0.0 -0.8      0.0    0.00   0.00      0.0   0.0
                  COMBINATION 13 DIRECT       0.0            4.0 0.8      -0.4    0.12   0.03      0.0   0.0
                  FATIGUE-CYCLE 500000.0 COMPLEX 7           11 12 13


       As an example, for Nx the equivalent equation to the above cyclic loading definition is:

                N x ( θ ) = 0.2 + 3.8 COS ( θ ) + 0.0 SIN ( θ )

       similarly for NY:

                N y ( θ ) = 2.0 + 0.0 COS ( θ ) + 4.0 SIN ( θ )

       These two equations are plotted as curves in Figure 6.3-2.

       The COMPLEX analysis procedure samples each harmonic loading at a series of discrete
       points through a cycle; the number of sample points used is specified in the FATIGUE-
       CYCLE command, in this case seven points. The sampling of the harmonic load is
       demonstrated in


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Concrete Suite – Application Manual                                                            Fatigue Limit State Check



       Figure 6.3-2 for loads Nx and NY. Once the COMPLEX loads have been sampled the
       requisite number of times, the rest of the analysis procedure is identical to that for a
       STEPPED definition.

       The correspondence between the COMPLEX and STEPPED methods is illustrated in the
       final part of Example 5 using the following instructions:

                  COMBINATION    1 DIRECT    4.000 2.000 -0.800 0.400 0.300 0.060 0.0 0.0
                  COMBINATION    2 DIRECT    2.569 5.127 0.127 0.087 0.394 0.083 0.0 0.0
                  COMBINATION    3 DIRECT   -0.646 5.900 0.958 0.010 0.417 0.089 0.0 0.0
                  COMBINATION    4 DIRECT   -3.224 3.736 1.068 0.226 0.352 0.073 0.0 0.0
                  COMBINATION    5 DIRECT   -3.224 0.264 0.374 0.574 0.248 0.047 0.0 0.0
                  COMBINATION    6 DIRECT   -0.646 -1.900 -0.602 0.790 0.183 0.031 0.0 0.0
                  COMBINATION    7 DIRECT    2.569 -1.127 -1.124 0.713 0.206 0.037 0.0 0.0

       Load combinations 1-7 have been redefined with the values calculated to correspond to
       the seven sampling points. The analysis is then run using a STEPPED fatigue cycle. In
       section 6.4 it will be shown that the results obtained are identical to those for the
       COMPLEX analysis.


6.4    OUTPUT DESCRIPTION


       The PRINT-DATA command produces a separate summary page for fatigue data. An
       example of this output is shown in Figure 6.4-1.

       The first two results tables produced by the example FLS run are for the STEPPED strip
       analysis on the 0° and 90° sections and are shown in Figures 6.4-2 and 6.4-3. Each table
       can be subdivided into four sections. Section one gives a brief summary of the input data.
       The second lists the stress in the various components for each of the seven load steps in
       turn. Obviously items parallel to the plane will show no load from the cycle, hence in the
       first table (0° section), the four centre rebars and both tendons see zero stress from the
       cyclic loading. The third section details the stress range endured through the cycle and
       gives the calculated annual damage. Finally a summary of the fatigue results, including
       the predicted fatigue life, is shown for all components as well as the usual Pass/Fail
       banner to clearly indicate the status of the FLS check. The 90° section passed the FLS
       check, but both the concrete extreme fibres and rebars failed the check on the 0° section.

       The third results table, shown in Figure 6.4-4 details the results obtained using the
       COMPLEX fatigue cycle. The analysis method has also been changed, to the layered
       approach, simply to illustrate that both methods are applicable to FLS analysis.

       The final part of the results listing, shown in Figure 6.4-5, demonstrates the exact
       synthesis of the COMPLEX method by the STEPPED analysis methods, i.e. that the
       COMPLEX method can be made to simulate the STEPPED method.




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                              Figure 6.3-1 S-N Curves Used in Example 5




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                   Figure 6.3-2 Method of Sampling Harmonic Loading




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                                                                                                                           Figure 6.4-1 PRINT-DATA Output Specific To An FLS Analysis




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                                                                                                                       Figure 6.4-2 (C ont.) STEPPED Analysis Results for 0° Section




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                                                                                                                           Figure 6.4-3 (C ont.) STEPPED Analysis Results for 90° Section




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                                                                                                                           •




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                                                                                                                       Figure 6.4-4 (Cont.) Results Using COMPLLEX Fatigue Cycle




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                                                                                                                       Figure 6.4-5 STEPPED Analysis Simulating Previous COMPLEX Results




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




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Concrete Suite – Application Manual                                                            Fatigue Limit State Check




                                                                                                                       Figure 6.4-5 (C ont.) STEPPED Analysis Simulating Previous COMPLEX Results




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks



7      IMPLOSION AND PANEL STABILITY CHECKS


7.1    INTRODUCTION


       This section discusses how implosion and panel stability checks are performed on
       cylindrical components and flat panels. Both of these checks cannot be interfaced with an
       FE analysis system; all data, including loadings, must be input directly by the user.

       The implosion check involves assessing the buckling and stability capacity of a concrete
       cylinder or partial cylinder (curved panel) subjected to external pressure loading in
       combination with other applied loads. The panel stability check calculates the buckling
       capacity of a flat concrete slab.

       The underlying methods used in performing implosion and panel stability checks are
       described in detail in the Theoretical Manual.


7.2    IMPLOSION EXAMPLE PROBLEM


       The cylinder and partial cylinder shown in Figures 7.2-1 and 7.2-2 are analysed in
       Example 6 for implosion failure using the input data file below:


                  !
                  ! APPLICATION MANUAL EXAMPLE 6
                  ! ===================================
                  !
                  ! IMPLOSION CHECKS
                  !
                  ! RUN CONTROL DATA
                  !
                  TITLE APPLICATION MANUAL EXAMPLE 6 (IMPLOSION CHECKS)
                  *
                  CODE-CHECK ON
                  !
                  ! PROVIDE SLAB DATA
                  !
                  MATERIAL-PARTIAL-SAFETY-FACTORS    1.30 1.00 1.00 1.00
                  CONCRETE-PROPERTIES BS8110 50.0 0.2
                  REBAR-PROPERTIES 1 365.0
                  REBAR-PROPERTIES 3 400.0 190000.0
                  REINFORCEMENT-BARS     1    1 0 25.0 800.0    25.0
                  REINFORCEMENT-BARS     2    3 0 25.0 750.0 750.0
                  TOP-STEEL     REBARS 1 25.0   0.0
                  TOP-STEEL     REBARS 2 50.0 90.0
                  BOTTOM-STEEL REBARS 2 25.0    0.0
                  BOTTOM-STEEL REBARS 1 50.0 90.0
                  !
                  ! IMPLOSION CHECK DATA
                  !
                  IMPLOSION-CHECK ON
                  IMPLOSION-CYLINDER 140.0 30.0
                  IMPLOSION-IMPERFECTION 75.0
                  IMPLOSION-LOADS 0.010 -3.0 -1.5 0.40 0.30
                  !
                  ! PERFORM IMPLOSION CHECK FOR TWO THICKNESSES OF SLAB
                  !
                  # 300 MM SLAB
                  CONCRETE-DEPTH 300.0
                  DO-CHECKS
                  #



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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks
                  # 350 MM SLAB
                  CONCRETE-DEPTH 350.0
                  DO-CHECKS!
                  ! PERFORM IMPLOSION CHECK FOR PARTIAL CYLINDER
                  !
                  IMPLOSION-CYLINDER 150.0      25.0   10.0    1.0
                  IMPLOSION-LOADS 0.20 0.50     0.65   0.50    0.10
                  #
                  # PARTIAL CYLINDER
                  DO-CHECKS
                  !
                  END


7.2.1 Implosion Check Specific Input Data

       The commands specific to an implosion analysis comprise the following:

                  IMPLOSION-CHECK ON
                  IMPLOSION-CYLINDER 140.0 30.0
                  IMPLOSION-IMPERFECTION 75.0
                  IMPLOSION-LOADS 0.010 -3.0 -1.5 0.40 0.30


       IMPLOSION-CHECK ON specifies that an implosion check is to be performed on the
       data at the next DO-CHECKS command. The dimensions (length and radius) of the
       cylinder are specified in the IMPLOSION-CYLINDER command. Note that the units of
       all arguments to this command are in metres, i.e. the cylinder specified is 140m long and
       60m in diameter. The maximum imperfection is specified as 75 millimetres and is used in
       the evaluation of the imperfection bending moment.

       The IMPLOSION-LOADS command defines the following loading:

                  Pressure                   0.01     MNm-2              (external)
                  Axial Load                 -3.0     MN per metre width
                  Bending Load               -1.5         ”        “     (maximum)
                  Shear                       0.4             ”            “

                  Torsion                     0.3             ”            “



       The properties of the slab section are specified in exactly the same manner as before, but
       it is worth noting that the X direction is assumed along the length of the cylinder and the
       Y axis is circumferential. Therefore all 0° reinforcement is axial and 90° reinforcement is
       radial.

       Example 6 includes a second check to illustrate the facilities available for checking partial
       cylinders. The partial cylinder is defined by specifying additional parameters to the
       IMPLOSION-CYLINDER command as follows:

                  IMPLOSION-CYLINDER 150.0 25.0 10.0 1.0


       The third parameter specifies the arc length of the partial cylinder (ten metres), the fourth
       parameter specifies the edge fixity as fully fixed. Note that for this check the loads have
       also been modified.




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks



7.2.2 Output Description

       Output from Example 6 comprises three main pages; the first two, shown in Figures 7.2-3
       and 7.2-4, represent output for implosion checks performed on full cylinders of different
       thickness, while Figure 7.2-5 shows output for the checks performed on the partial
       cylinder.

       The formats of the three pages are identical, the first section shows the specified and
       derived input data for the implosion checks. This is followed by results for each of the
       three methods used in the analysis namely; DnV Appendix D, Chrapowicki and DnV
       Appendix C. The modified DnV Appendix C approach is considered to produce the most
       realistic and accurate results for implosion checks, therefore the results from this method
       are used when calculating the interaction factor of safety. The final section displays the
       results of the imperfection bending moment evaluation. Since the interaction factors of
       safety all exceed unity, the cylinder and partial cylinder sections are considered to be
       satisfactory for the implosion checks. This is further indicated by the ‘SAFE’ banner at
       the bottom of each page of output.

       It should be noted that for the partial cylinder implosion check the pre-buckling applied
       stresses are listed as zero in the DnV Appendix C results; this is because they were input
       as tensile loads, and are therefore assumed not to contribute to buckling.


7.3    PANEL STABILITY EXAMPLE PROBLEM


       Example 7 performs a buckling check on the flat panel detailed in Figure 7.3-1, when it is
       subjected to the in-plane loadings shown. The data file used is listed below:
                  !
                  ! APPLICATION MANUAL EXAMPLE 7
                  ! ==============================
                  !
                  ! PANEL STABILITY CHECKS
                  !
                  ! RUN CONTROL DATA
                  !
                  TITLE APPLICATION MANUAL EXAMPLE 7 (PANEL STABILITY CHECKS)
                  *
                  CODE-CHECK ON
                  !
                  ! PROVIDE SLAB DATA
                  !
                  MATERIAL-PARTIAL-SAFETY-FACTORS      1.30    1.00   1.00    1.00
                  CONCRETE-PROPERTIES BS8110 50.0 0.2
                  REBAR-PROPERTIES1 365.0
                  REBAR-PROPERTIES3 400.0 190000.0
                  REINFORCEMENT-BARS 1 1 0 25.0 800.0          25.0
                  REINFORCEMENT-BARS 2 3 0 25.0 750.0          750.0
                  TOP-STEEL     REBARS 1 25.0   0.0
                  TOP-STEEL     REBARS 2 50.0    90.0
                  BOTTOM-STEEL REBARS 2 25.0     0.0
                  BOTTOM-STEEL REBARS 1 50.0     90.0
                  !
                  ! PANEL STABILITY CHECK DATA
                  !
                  PANEL-STABILITY-CHECK ON
                  PANEL-DIMENSIONS 80.0 50.0
                  PANEL-IMPERFECTION 75.0
                  PANEL-LOADS 0.10 -3.0 -0.05 0.10
                  !
                  ! PERFORM PANEL STABILITY CHECK FOR TWO DIFFERENT SLAB THICKNESSES
                  !



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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks
                  # 300 MM SLAB
                  CONCRETE-DEPTH 300.0
                  DO-CHECKS
                  #
                  # 350 MM SLAB
                  CONCRETE-DEPTH
                  350.0 DO-CHECKS
                  !
                  END


7.3.1 Panel Stability Specific Input Data

       The commands specific to a panel buckling analysis are as follows:

                  PANEL-STABILITY-CHECK ON
                  PANEL-DIMENSIONS 80.0 50.0
                  PANEL-IMPERFECTION 75.0
                  PANEL-LOADS 0.10 -3.0 -0.05 0.10


       PANEL-STABILITY-CHECK ON specifies that a panel buckling analysis is to be
       performed at the next DO-CHECKS instruction. The dimensions of the panel (length and
       width) are specified using the PANEL-DIMENSIONS command, again note that both
       values must be specified in metres. The dimensions also define the panel axis system,
       length is measured in the X-axis, width in the Y-axis direction. This orientation is
       important when specifying the slab section properties and panel loadings. The final
       parameter to the PANEL-DIMENSIONS command specifies the panel edge fixity, in this
       case, imply supported.

       The PANEL-LOADS command is used to define the out-of-plane uniform pressure and
       in-plane loads acting on the panel. The four parameters specify the following loads:

        Out-of-plane Pressure Load                                   0.10 MN - 2
        In-plane Load (X-direction)                                  -0.30 MN per metre width
        In-plane Load (Y-direction)                                  -0.05 "     "
        Shear                                                        0.10      "        "




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks


       The PANEL-IMPERFECTION command specifies the maximum out-of-plane
       imperfection in the flat panel. This facility is not implemented in the analysis method at
       present, but because the value of the parameter is included in the results listing, a
       description has been included here.

7.3.2 Output Description

       The main output from Example 7 essentially comprises two pages, one for each thickness
       of panel analysed.

       The first section of output shows the specified and derived input data. The second section
       lists the results for the panel in both the simply supported (IDWR) and fully fixed support
       (Roark/Levy) conditions. The results displayed include the applied stress, critical
       buckling stress, factors of safety and combined factor of safety.

       For both panels analysed the combined factors of safety exceed unity, therefore they are
       considered to be satisfactory. Again this is highlighted by the banner at the bottom of each
       page of output.




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




                           Figure 7.2.-1 Cylinder to be Analysed in Example 6




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




                    Figure 7.2-2 Partial Cylinder to be Analysed in Example 6


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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




                                                                                                                       Figure 7.2-3 Example 6 – Full Cylinder Implosion Check Results (300mm Thick)




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




                                                                                                                       Figure 7.2-4 Example 6 – Full Cylinder Implosion Check Results (350mm Thick)




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




                                0.1 MN PER
                               METRE WIDTH




                 Figure 7.3-1 Panel Dimensions and Loads Used in Example 7




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




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Concrete Suite – Application Manual                                             Implosion and Panel Stability Checks




                                                                                                                          Figure 7.3-3 Example 7 – Stability Check: 350mm Thick Panel




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Concrete Suite – Application Manual                                               Post-Processing of SESAM Models


8     POST PROCESSING OF SESAM MODELS


8.1    GENERAL CAPABILITIES

       Concrete structures modelled using the SESAM PE analysis program can be code checked
       using the CONCRETE Suite of programs, with the current limitation that the programs
       can only operate on solid element models.

       Before any CONCRETE program can be used to process the results from a SESAM FE
       analysis, some pre-processing must be performed. First the combined load cases must be
       generated from the basic (generally unit) load cases used in the FE analysis, this is
       generally performed using the PREPOST program. The final pre-processing involves
       nodally averaging the gauss point data produced by SESAM using the SIFAVERAGE
       program. A quick guide to SIF-AVERAGE, using examples, is provided in Section 8.3;
       full details of the program are provided in the SIF-AVERAGE User Manual.

       Once a CONCRETE compatible results file has been produced, the processing can follow
       two routes:

             − enveloping of load cases using CONCRETE-ENVELOPE followed by code
               checking using CONCRETE-CHECK;

             − code checking directly from the FE results using CONCRETE-CHECK.

       Only the latter option, code checking directly from the FE results, will be covered in this
       chapter.


8.2    EXAMPLE PROBLEMS


       The examples considered in this chapter are based on analysing the SESAM PE model of
       an offshore concrete platform. The examples perform ULS, SLS and FLS checks on
       superelement BB00T103 which models the outer skirt of the Brent Bravo platform. The
       location and details of this superelement are shown in Figures 8.2-1 and 8.2-2.

       Prior to using SIF-AVERAGE, the basic SESAM results for superelement BB00T103
       have to be converted using the PREPOST utility to produce a NORSAM formatted
       SESAM Interface (SIN) file containing the basic load cases. In turn this file may be
       processed, again using PREPOST, to extend the SIN file to contain the combined load
       case results if so required. The details of how this processing is performed is beyond the
       scope of this manual (refer to the relevant SESAM documentation). It will simply be
       assumed that the file BB00T103C.SIN exists. Note that the C has been added to the
       standard SESAM filename to denote that the SIN file contains combined results.




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Concrete Suite – Application Manual                                               Post-Processing of SESAM Models




8.3    USE OF SIF-AVERAGE PROGRAM


       Besides nodally averaging the SESAM results, the SIF-AVERAGE program also allows
       the user to associate subsets of elements into groups within the superelement for selective
       processing by the CONCRETE Suite. This section details how two groups have been
       selected and averaged for superelement BB00T103.

       The data file used to SIF-AVERAGE the BB00T103 superelement is listed below:

              ECHO ON
              SUPER-ELEMENT BB00 T103C
              LOAD   70   71   72   73   74   75   76   77   78   79   80   81
              ORIGIN   20000.0   0.0   3400
              SELECT INSIDE
              GROUP 1
              ADD BOX   10307.7641 10307.7641 5000 –10000 2500 0 –10000 –2500 0 0 0 1
              AVERAGE
              GROUP 2
              ADD CYL   5000   10200   0   0   1
              SUB BOX   10307.7641 10307.7641 5000 –10000 2500 0 –10000 –2500 0 0 0 1
              AVERAGE
              END

       The purpose of each instruction is as follows. The ECHO ON simply instructs the
       program that the user requires the input data to be echoed in the output file. The SUPER-
       ELEMENT command selects the model and superelement to be averaged. In this case, the
       BB00 model and superelement T103. The additional C appended to the superelement
       name specifies that the combined results file BB00T103C.SIN is to be used.

       The LOADCASES instruction specifies which of the combined loadcases in the results
       file are to be averaged, for this example twelve loadcases have been selected.

       By default SIF-AVERAGE uses the superelement origin as its own origin. This may not
       be the most suitable; therefore an ORIGIN command can be used to define a point
       relative to the superelement origin which will be used by all subsequent SIF-AVERAGE
       commands. In the data file a SIF-AVERAGE origin has been defined at the point (20000,
       0, 3400).

       To facilitate the selection of subsets of elements for the current group, the program allows
       the user to define volumetric shapes. The user can then select all elements which lie
       wholly INSIDE, wholly OUTSIDE or are CROSSING the volume boundary. In this case
       the SELECT INSIDE command indicates that all elements completely INSIDE the
       boundary will be selected.

       The GROUP command initiates the creation of a new list of elements to be associated
       with the specified group number. All elements chosen, using the available selection
       methods, will be added or deleted from the element list for the group. In total two groups
       are defined in this example.

       The ADD BOX command is quite complex and therefore requires detailed explanation.
       The parameters following the first occurrence of the command can be subdivided into
       four definitions as follows:



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Concrete Suite – Application Manual                                               Post-Processing of SESAM Models




                  10307.7641 10307.7641 5000                      - defines dimensions of box
                  -10000    2500 0                                - defines vector 1
                  -10000 -2500 0                                  - defines vector 2
                  0        0     1                                - defines vector 3

       Figure 8.3-1 shows how the three vectors and dimensions above define the selection
       volume. Note that the dimensions are all measured from the SIF-AVERAGE origin. The
       result of the ADD BOX command is that eight elements are selected for the current group
       (GROUP 1).

       The AVERAGE command causes SIF-AVERAGE to temporarily suspend the input of
       data and to produce nodally averaged stresses using the latest input data. These derived
       nodal stresses are stored back to the interface file along with the current group
       information.

       A different selection method has been adopted for the second group. The ADD CYL
       defines a cylindrical volume, centred on the SIF-AVERAGE origin, radius 10200mm.
       The axis of the cylinder is defined by the vector (0, 0, 1) i.e. parallel to the Z-axis and the
       length of the cylinder is 5000mm along this vector. The cylinder and its position relative
       to the superelement are shown in Figure 8.3-2.

       The ADD BOX command has actually selected some of the elements included in GROUP
       1. The SUB BOX command defines an identical box volume to the ADD BOX used to
       select the first group, but instead of being added to the list, the elements selected are
       subtracted from the current group element list. The command is used here to subtract
       unwanted elements captured by the preceding ADD CYLINDER command. In total the
       ADD and SUB commands select twenty elements for the current group (GROUP 2).

       The END command is used to terminate the current run, closing all files and returning to
       the operating system. It is identical to the STOP command and either can be used.


8.4    CODE CHECKING SUPERELEMENT BB00T103

       The data file used in Example 8 is listed below:
              SUPER-ELEMENT BB00 T103C
              ECHO ON
              OUTPUT-LEVEL DETAILED FULL
              * STRESS RECOVERY DIRECTLY FROM SESAM
              LIST-INPUT-DATA ON
              !
              ! CONCRETE-CHECK RECOVERY DIRECTLY FROM SESAM
              !
              ! RUN CONTROL DATA
              !
              ANALYSE-NODE-CLASSES 4
              TITLE EXAMPLE 8 - CONCRETE-CHECK STRESS RECOVERY DIRECTLY FROM SESAM
              GROUP 1
              ORIGIN 10000.0 50.0 3500.0
              SURFACE PLANE 0 -1 0
              DATUM 1 0 0
              UNITS 1.0 1.0
              BEGIN-PLOT
              SECTION 1 LIST 50.0 300.0 900.0 1200.0 1600.0 2000.0 2500.0 3200.0
              DATA-CHECK-ONLY
              CODE-CHECK ON


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Concrete Suite – Application Manual                                               Post-Processing of SESAM Models
              ENVELOPE-NUMBER 1
              ENVELOPE-NAME LOAD CASE 71 0 DEG OPERATING
              MATERIAL-PARTIAL-SAFETY-FACTORS 1.50 1.15 1.15 1.25
              METHOD LAYER 10 200
              !
              ! SLAB GEOMETRY
              !
              CONCRETE-DEPTH 1710.0
              CONCRETE-PROPERTIES BS8110 60.0 0.2
              REBAR-PROPERTIES 1 400.0
              !
              ! REINFORCEMENT REFERENCE
              ! DRAWING 3951-416-02-202c (SECTION 3-3)
              !
              ! HOOP REINFORCEMENT
              !
              REINFORCEMENT-BARS 1 1 1 25.0 240.0 240.0
              !
              ! VERTICAL REINFORCEMENT
              !
              REINFORCEMENT-BARS 2 1 1 25.0 130.0 25.0
              REINFORCEMENT-BARS 3 1 1 25.0 130.0 130.0
              TOP-STEEL   REBARS 1 75.0 90.0 0.25
              TOP-STEEL   REBARS 2 100.0 0.0 0.25
              TOP-STEEL   REBARS 3 755.0 0.0 0.25
              TOP-STEEL   REBARS 1 780.0 90.0 0.25
              BOTTOM-STEEL       REBARS 1 780.0 90.0 0.25
              BOTTOM-STEEL       REBARS 3 755.0 0.0 0.25
              BOTTOM-STEEL       REBARS 2 100.0 0.0 0.25
              BOTTOM-STEEL       REBARS 1 75.0 90.0 0.25
              TENDON-PROPERTIES 1 1755.0 195000.0 0.005
              PRESTRESS-TENDONS 1 1 1 12 13 150.0 1.43351
              TOP-STEEL TENDONS 1 427.5 90.0
              TOP-STEEL TENDONS 1 780.0 90.0
              BOTTOM-STEEL TENDONS 1 780.0 90.0
              BOTTOM-STEEL TENDONS 1 427.5 90.0
              !
              ! LOAD DATA
              !
              ENVELOPE ANALYSIS 71
              PRESTRESS-LOADS TOTAL ANALYSIS 79
              #
              # STRENGTH, SERVICE AND FATIGUE CHECKS
              # ******************************************
              !
              ! ULTIMATE AND STRENGTH CHECK DATA
              !
              STRENGTH-CHECK ON
              SHEAR-REINFORCEMENT 20 1 200 200
              REDESIGN 10
              !
              ! PRINT DATA AND PERFORM CHECKS
              !
              PRINT-DATA
              DO-CHECKS
              STRENGTH-CHECK OFF
              !
              ! SERVICE CHECK DATA
              !
              MATERIAL-PARTIAL-SAFETY-FACTORS 1.30 1.0 1.0 1.25
              SERVICE-CHECK ON
              SERVICE-CRITERIA 0.25 150.0
              !
              ! PERFORM CHECKS
              !
              DO-CHECKS
              SERVICE-CHECK OFF
              !
              ! FATIGUE CHECK DATA
              !
              MATERIAL-PARTIAL-SAFETY-FACTORS 1.30 1.0 1.0 1.25
              FATIGUE-CHECK ON
              FATIGUE-LIFE 60.0
              CONCRETE-S-N-CURVE 10.0 8.0
              STEEL-S-N-CURVE 1 400 10177.5 6.0 235 251773.5 2.8 65 8831122.1 4.8
              !
              ! ANALYSE USING STEPPED WAVE
              !
              COMBINATION 1 ANALYSIS 80
              COMBINATION 2 ANALYSIS 81


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              STATIC-COMBINATION ANALYSIS 70
              FATIGUE-CYCLE 500000.0 STEPPED 1 2
              !
              ! PERFORM CHECKS
              !
              DO-CHECKS
              FINISH-PLOT
              END


8.4.1 Run Control Data

       When CONCRETE-CHECK is used to analyse the results from an FE analysis, a
       SUPER-ELEMENT command has to be included to specify which file contains the
       results data. In this example the command:

                   SUPER-ELEMENT BB00 T103C

       is used to specify the prefix and filename of the results file, in this case B00T103C.SIN.

8.4.2 Definition Of Locations To Be Checked

       The basic concept of using sections was introduced in Chapter 4, but at that stage the
       program was being run in stand-alone mode with the sections merely acting as location
       identifiers. Now that the structure has been modelled as a three-dimensional solid, with
       stresses defined at every element node, the full section facilities can be exploited. A
       section is taken through the model by intersecting a surface with a subset of elements.
       Locations can then be specified around the section, either by distance or angle, from a
       start position on the section defined by a datum vector. Available surfaces are PLANE,
       CYLINDER and CONE, which must be specified by an ORIGIN and either a unit normal
       vector or an axis vector and a physical dimension. Full details on how to define sections is
       given in Section 4.10 of the CONCRETE-CHECK User Manual.

       In Example 8 a subset of elements and a PLANE surface are defined by the following
       instructions:

              GROUP 1
              ORIGIN 10000.0 50.0 3500.0
              SURFACE PLANE 0 -1 0
              DATUM 1 0 0
              SECTION 1 LIST 50.0 300.0 900.0 1200.0 1600.0 2000.0 2500.0 3200.0

       The surface and locations defined by the above instruction are shown in Figure 8.4-1

8.4.3 Load Case Data

       In previous examples the loading had to be specified in the data file using ENVELOPE,
       PRESTRESS-LOADS and COMBINATION instructions with the DIRECT option. The
       loads had to be entered via the command line. When CONCRETE is interfaced with an
       FE system, the loadings can be obtained directly from the FE results file. This operation
       requires a slight alteration to the ENVELOPE and PRESTRESS-LOADS commands. In
       Example 8 the following instructions are used:
                  ENVELOPE ANALYSIS 71
                  PRESTRESS-LOADS TOTAL ANALYSIS 79
                  COMBINATION 1 ANALYSIS 80
                  COMBI NATI ON 2 ANA LYSI S 81




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       The ANALYSIS parameter signifies that the data is to be obtained from the FE results file
       pointed to by the SUPER-ELEMENT command. The ENVELOPE instruction accesses
       the data in load case 71 and the prestress data is obtained from load case 79. The loading
       data for the fatigue analysis is obtained from load cases 80 and 81.


8.5    OUTPUT FROM EXAMPLE 8


       When a section is defined, the first data output after a DO-CHECKS instruction gives
       details of which elements were intersected by the surface along with the coordinates of
       the intersecting edges. This output is shown in Figure 8.5-1.

       The SECTION instruction includes a list of eight locations to be checked. Results are
       output for each location in turn. Typical results, in this case for the last list point, are
       displayed in Figures 8.5-2 to 8.5-4. It should be noted that for this example, which checks
       eight locations for ULS, SLS and FLS, fifty-nine pages of detailed output are produced.
       This explains why the user is recommended to reference the summary output shown in
       Figure 8.5-5 first.




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                   Figure 8.2-1 Location of Brent Bravo Superelement T103



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                          Figure 8.2-2 Details of Superelement T103



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                                                                                                                    Figure 8.3-1 Selection using ADD BOX Of Elements for GROUP 1 From Superelement BB00T103




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                                                                                                                    Figure 8.3-2 Selection using ADD CYL & SUB BOX Of Elements for GROUP 2




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        /




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                                                                                                                    Figure 8.5-1 Intersection of Plane With Elements Information




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                                                                                                                    Figure 8.5-2 Example 9 – ULS Results For Section 1, Location 8




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                                                                                                                    Figure 8.5-2 (Cont.) Example 8 – ULS Results for Section 1, Location 8




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                                                                                                                    Figure 8.5-4 Example 8 – FLS Results for Section 1, Location 8




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                                                                                                                    Figure 8.5-4 (Cont.) Example 8 – FLS Results for Section 1, Location 8




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                                                                                                                    Figure 8.5-5 Summary Output for Example 8




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