Ready Mix Concrete Quality Management System Procedures

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            dvancements in cementitious materials, admix-           pervious concrete that,
            tures, and reinforcing are expanding the applica-       according to the com-
            tions and durability of concrete in all its forms       pany, is a viable solution
            — ready mixed, precast, and prestressed. Addi-          for stormwater man-
tionally, non-destructive testing techniques and equipment          agement, better land
enhance asset management by providing a more accurate               utilization, and LEED
evaluation of the condition and performance of existing con-        credits. BASF Admix-
crete pavements and structures. In response to a request from       tures’ pervious mixture
CE News, companies provided the following information               combines Polyheed polycarboxylate-based, mid-range water-
about their concrete products and related components.               reducing admixtures, Delvo Stabilizer hydration-controlling
                                                                    admixtures, and Rheomac VMA viscosity-modifying ad-
   AltusGroup,	Inc., continued expanding the network of             mixtures. This combination assists in achieving the desired
companies that can provide its CarbonCast precast technol-          strength by creating a strong paste-to-coarse-aggregate bond
ogy. Recent additions include Heldenfels Enterprises, Inc.,         and maximizing cement hydration and a longer working
San Marcos, Texas, with markets along the Western Gulf              window for placement, BASF says. It eliminates the need
Coast; Encon United, Denver, Colo., focusing on transpor-           to retemper the mix on the jobsite and adds body and helps
tation-related products; and GPRM Prestress, Kapolei, Ha-           lubricate the mix. The result is better flow, faster discharge
waii, focusing on architectural and structural components.          time, and easier placement and compaction.
In addition, North American cement producer Essroc will
research how its TX Active photocatalytic cement technol-              The Concrete	 Reinforcing	
ogy for self-cleaning and pollution-mitigating concrete can         Steel	Institute	(CRSI) offers a
add to CarbonCast’s sustainability benefits. CarbonCast             reprint of a six-page article, “Re-
uses a non-corrosive, high-strength carbon fiber grid called        sisting Corrosion,” which origi-
C-GRID as secondary reinforcing in precast concrete prod-           nally appeared in Public Roads, a
ucts. According to the company, C-GRID allows design and            Federal Highway Administration
production of thinner precast sections with improved corro-         (FHWA) publication. The article
sion resistance and durability.                                     discusses the ability of various
                                                                    types of concrete steel reinforcing
    The	 American	 Concrete	 Pavement	 Association’s	               bar to resist corrosion, based on
technical publication, Design of Concrete Pavement for              two FHWA corrosion research
Streets and Roads, provides an overview of all major variables      projects that tested a variety of reinforcing materials. Also
in street and roadway design and also offers tips and techni-       provided in the article are several charts that provide side-
cal information to assist designers, consultants, contractors,      by-side comparisons of uncoated (black) steel reinforcing,
and others involved in pavement design. The publication is          epoxy-coated steel reinforcing, and non-magnetic stainless
organized into seven topic areas: street classification and traf-   steel reinforcing. The research projects were conducted from
fic, geometric design considerations, subgrades and subbases,       1993 to 2002 on concrete slabs. According to CRSI, one of
concrete quality, thickness design, jointing, and construction      the most notable conclusions of the research is that when
specifications. The 16-page publication includes more than          epoxy-coated bar is used in a top mat directly above uncoated
a dozen charts, including reliability, projected slab cracking      bar, its susceptibility to corrosion is cut by at least 50 percent
values, traffic and thickness correlations, axle load distribu-     when compared with using only black bar.
tions, and subgrade/subbase strength models. The reference
resource also includes engineering drawings showing typical            Cortec’s Migratory Cor-
cross sections of joint types, typical two-lane roadway sections,   rosion Inhibitor (MCI)-2005
two-lane sections with parking, and three-lane sections.            AL water-based concrete
                                                                    admixture, based on ami-
   BASF	Admixtures developed a proprietary mix design               nocarboxylate     technology,
using its Master Builders brand of products to produce              tolerates extreme cold and	                                                                                    JANUARY 2007 CE NEWS            49	

hot temperatures. According to the company, the admixture         broad range of nondestructive testing, including inspection
forms a protective layer on embedded reinforcement that           of walls, floors, decks, slabs, tunnels, balconies, and garages.
prevents corrosion caused by carbonation, chlorides, and          The system can also locate rebar, tension cables, conduits,
atmospheric attacks, providing corrosion protection for           and voids, or it can be used to measure slab thickness. Data is
steel reinforcement, carbon steel, galvanized steel, and other    collected with an optical reader, which provides the user the
metals embedded in concrete structures. Tests performed on        ability to resolve smaller targets in concrete with precision
MCI-2005 AL showed a significant reduction in corrosion           and ease. The StructureScan system also combines GSSI’s
rates, improvement in compressive and flexural strengths,         most advanced GPR system with a rugged laptop computer
and no effect on concrete set times. MCI-2005 AL can              to produce advanced 3-D concrete inspection data.
be added directly to the mix at the ready-mix plant, to the
ready-mix truck drum, or used in portable mixers.                    Gilson’s          HM-251
                                                                  Concrete Thermal Expan-
   Creative	 Design	                                              sion (CTE) unit, the first
Resolutions,	 Inc.	                                               commercially available CTE
(CDR), designs con-                                               unit, is a fully automated
text-sensitive highway                                            system that allows testing
and     transportation                                            of a single, 4-inch concrete
infrastructure      and                                           core or cylinder specimen
amenities, including                                              for length change at varying
sound barriers, sidewalks, facades, and fountains. CDR says it    temperatures in accordance
uses site-specific and cost-effective approaches that consider    with AASHTO TP-60. Length measurements are reported
the surrounding architecture, philosophy, history, aesthetics,    accurately using an LVDT, and temperature is controlled and
natural environment, needs, values, and visions of the commu-     reported accurately using a thermistor. Software is included
nity. Precast concrete highway barrier walls can be built using   for logging length change and temperature change, as well
custom or off-the-shelf form liners and normal construction       as calculated thermal expansion and contraction coefficients.
methods. Many of the company’s designs are modular and            HM-251 features include computer-controlled water bath
can be reconfigured to create miles of unique designs using a     temperature, stainless calibration bar, a re-circulator capable
finite number of original form liner patterns.                    of complete water exchange every 30 seconds for minimized
                                                                  temperature gradients in the water bath, and automatic wa-
   FORTA	 Corporation intro-                                      ter-level control to maximize test accuracy.
duced synthetic fibers to the U.S.
market in 1978 to control cracking                                    Hilti’s PROFIS Anchor software
in concrete. Since that time, stan-                               provides 3-D anchor design. The pro-
dard fiber types have been used in                                gram, which supports allowable stress
relatively low dosages — 1.0 to 1.5                               design and load-resistance factor de-
pounds per cubic yard — to control                                sign in accordance with ACI-318-02
cracking caused by shrinkage and                                  Appendix D/AC193 and ICC, allows
temperature-related concrete issues.                              users to choose the level of detail or
In the past six years, FORTA has                                  complexity needed for each project, from quick calculation in
introduced what it calls the next-generation of structural        a few steps to full definition of all variables. PROFIS also
or macro synthetic fibers, which are used at higher dosages       features a comprehensive, easy-to-use anchor selector, a da-
and longer lengths, to allow for a much greater replacement       tabase of exportable CAD drawings for all Hilti anchors, and
level of conventional steel reinforcement in a wide variety of    a library of anchor approvals and specifications. A full-screen
flatwork, precast, and shotcrete applications.                    graphical input includes all dimensions for visualization.

   Geophysical	Survey	Systems,	                                      Hydrotimer introduced a self-contained
Inc.’s	 (GSSI), StructureScan ground                              outflow meter to test surface drainage on
penetrating radar (GPR) features a                                concrete and asphalt pavements. The purpose
1-GHz antenna that, according to                                  of the device is to measure the ability of the
the company, can penetrate concrete                               pavement to relieve water pressure at the tire
to a depth of 24 inches or more in                                footprint, thus giving an indication of vehicu-
3-D. The StructureScan concrete                                   lar skidding and hydroplaning potential under
inspection system can be used for a                               wet weather conditions. The outflow meter

50	      CE NEWS JANUARY 2007                                                                          
can be operated by a single person, and is not operator-sensi-      Precast	       Specialties	
tive. It contains an on-board digital readout displaying test    Corporation	 (PSC) offers
results, and conforms to the ASTM International E-2380-          a wide range of Precast Con-
05 specification.                                                crete Roadway Products in
                                                                 standard configurations from
   The	      International	      Code	                           stock, or in custom sizes to
Council’s (ICC) field practices                                  meet project specifications.
guide, Concrete Manual, has been                                 PSC roadway products in-
updated to the requirements of the                               clude 18-inch- or 24-inch-high straight curbing in lengths
2006 International Building Code                                 from 2 to 6 feet, radius curbing in many standard radii
and ACI 318-05. In addition to be-                               from 2 to 70 feet, radius corners, angled corners, inlets, and
ing a required reference for ICC’s                               sidewalk ramps (straight or radius). PSC also offers park-
Reinforced Concrete Special Inspec-                              ing-lot bumpers in car or truck size; custom light-pole bases;
tion certification exam, the Concrete                            and standard city of Boston light and traffic-signal bases,
Manual provides guidance and information to become more          handholes, pull boxes, pull-box extenders, posts, and survey
proficient in concrete field practices. The guide introduces     bounds. All PSC roadway products are made from air-en-
concrete and its behavior, explains conventional construction    trained, superplasticized, 5,000-psi concrete.
procedures, discusses control and inspection procedures,
explores statistical quality control methods and their ap-          Saint-Gobain	Vetrotex’s
plication to concrete construction, and details proper field     Specialty       Reinforcement
testing procedures and proper placement of reinforcement.        Group offers a full line of
The Concrete Manual also includes contact information for        products for fiber-reinforced
industry and technical organizations, as well as a CD-ROM        concrete. Its FibraFLEX,
containing the complete Concrete Manual in PDF format.           an engineered stainless alloy
                                                                 fiber, was developed in the
   The Post-Tensioning	 Institute’s (PTI) third edition          early 1980s through a process that freezes the alloy of iron
of its manual, Design of Post-Tensioned Slabs-on-Ground,         and chromium in an amorphous state. The design has been
focuses on geotechnical design parameters for two types of       used in Europe to manufacture fiber-reinforced concrete
post-tensioned, ground-supported foundations — ribbed            containers for the final disposal of low- and medium-level
foundations and uniform thickness foundations. All proce-        radioactive waste. According to the company, the fiber never
dures are provided to guide the designer to the applicable       rusts, even when in contact with sewage, salt water, deicing
design system and its limitations. Major areas covered in-       conditions, and other aggressive environments. FibraFLEX
clude slabs-on-stable soils, geotechnical investigation, soil-   fibers are extremely thin strips, in the range of 3.71 Denier,
structure interaction, and structural design procedure for       which helps maintain higher fiber count compared with steel
shallow post-tensioned foundations. Appendices provide           fibers. The higher fiber count improves toughness, impact,
design examples of residential foundations on expansive soil     shatter, and abrasion resistance, and reduces plastic shrink-
in different climates.                                           age and settlement cracking.

   The Precast/Prestressed	Concrete	Institute	(PCI)	                Sensors	 &	 Software,	
produced a bridge-repair manual, Manual for the Evalu-           Inc.’s, ground penetrating radar
ation and Repair of Precast, Prestressed Concrete Bridge         systems are used worldwide for
Products, to aid designers and state agency officials in         applications such as buried util-
evaluating damage that can occur with precast concrete           ity mapping, road and concrete
components during early stages in the precast plant,             structure inspection, forensics,
in transit, or during erection of a beam, deck panels, or        and archaeological investiga-
similar products. The manual also presents methods to re-        tions. Its Conquest systems are
pair defects to keep bridge construction on schedule. The        designed for quick evaluation
manual has chapters on troubleshooting approaches, stan-         of concrete. According to the
dard repair procedures, patching methods, epoxy-injection        company, Conquest delivers fast, real-time imaging for us-
procedures, and references for additional information. The       ers who need to evaluate, drill, or cut structures on the spot.
troubleshooting guide features sections on causes and pre-       The system locates rebar, conduits, post-tension cables, and
vention of common damage, as well as engineering effects         reinforcing wire mesh, and transfers data to a PC for further
and repair considerations.                                       enhancement or inclusion in reports.	                                                                                JANUARY 2007 CE NEWS          51	

   StructureWorks’ PrecastMC has been developed as an                one to three times faster than nor-
electronic workbook for Mathcad 13. The electronic work-             mal for mortar and concrete, and
book contains files to aid in the design and development of          improves workability and strength
precast, prestressed engineering connections; members; and           while hastening cement hydra-
projects, including plate and weld design. The worksheets            tion. Removing forms and other
have been developed around the latest design codes — ACI             protection earlier and initiating
318-99, ACI 318-02, and the PCI 6th edition Design Hand-             concrete finishing saves time and
book. The worksheets have common design elements for                 labor. HYDRASET-FREE is
input and output. They reference additional worksheets and           recommended for use during cool
DLL functions so users can develop their own worksheets.             and cold weather to accelerate the
PrecastMC includes the reference function requirements for           set time and reduce the risk of frozen mortar and concrete
input and output.                                                    mixes, but it also can increase workability and earlier strength
                                                                     when temperatures are in the 50° to 65° F range.
   The	Transtec	Group,	Inc., launched a website at www. to provide a single source of informa-
tion for transportation agencies and the precast concrete
and concrete paving industries to become more informed                    To obtain more information about any of the products
about the benefits of precast, prestressed concrete pavement           featured in this Product Guide, click on the InfoDirect
technology. The concept for precast, prestressed, concrete             link at and enter the appropriate
pavement, originally developed in the late 1990s under a               InfoDirect number indicated below, or mail the reader
Federal Highway Administration-sponsored feasibility study,            response card found in the back of this issue. See our
provides an alternative to traditional rapid pavement reha-
                                                                       Reader Resource listing on page 57 for details.
bilitation techniques such as hot-mix asphalt and fast-setting
concretes. Use of precast concrete panels reduces user delays          Company Name                                InfoDirect No.
during construction while providing a durable, long-term so-
                                                                       AltusGroup, Inc.                                 940
lution. The website includes background information on the
concept, benefits, articles and reports about precast pavement,        American Concrete Pavement Association           941
and a list of upcoming events related to precast pavement.             BASF Admixtures                                  942
                                                                       Concrete Reinforcing Steel Institute             943
   V&A	 Consulting	 Engineers developed the VANDA
Concrete Corrosion Index, a simplified, four-level visual rat-         Cortec                                           944
ing system for characterizing the type and amount of degra-            Creative Design Resolutions, Inc.                945
dation observed on reinforced concrete tanks, pipelines, and
                                                                       FORTA Corporation                                946
other structures. According to the firm, the index makes it
easier to deliver accurate, quantitative reports based on specific     Geophysical Survey Systems, Inc.                 947
field observations of the overall appearance, smoothness, loss         Gilson                                           948
of hardness, cracking, spalling, and condition of reinforcing
                                                                       Hilti                                            949
steel. Additionally, it provides senior-level decision-makers,
who may never inspect the site themselves, a more hands-on             Hydrotimer                                       950
understanding of field conditions. It can make GASB 34                 International Code Council                       951
compliance easier for utilities and municipalities, V&A says,
                                                                       Post-Tensioning Institute                        952
by facilitating assessment of infrastructure assets.
                                                                       Precast/Prestressed Concrete Institute           953
                                                                       Precast Specialties Corporation                  954
                                                                       Saint-Gobain Vetrotex                            955
                                                                       Sensors & Software, Inc.                         956
                                                                       StructureWorks                                   957
                                                                       The Transtec Group, Inc.                         958
  W.R.	 Meadows’	 HYDRASET-FREE Non-Chloride                           V&A Consulting Engineers                         959
Concrete Set Accelerator is a ready-to-use, liquid admixture.          W.R. Meadows                                     960
According to the company, it accelerates initial setting time

52	      CE NEWS JANUARY 2007                                                                             

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