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    <title>Transport Research International Documentation (TRID)</title>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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    <item>
      <title>Rehabilitation of Continuously Reinforced Concrete Pavement with Bonded Overlay</title>
      <link>https://trid.trb.org/View/890495</link>
      <description><![CDATA[In Texas, many miles of old Portland cement concrete (PCC) pavement need rehabilitation due to their deficient structural capacity and resulting pavement distresses. Bonded concrete overlay (BCO) presents one of the rehabilitation strategies to strengthen PCCP systems. In 1986, the Texas Department of Transportation (TxDOT) constructed a 4-inch BCO on existing continuously reinforced concrete pavement (CRCP) in Houston. A factorial design was developed to evaluate the effects of different materials/design features and the condition of existing pavement. Test sections were placed in accordance with the factorial experiment. Materials included were siliceous river gravel and crushed limestone as coarse aggregates. The use of welded wire fabric and steel fibers was the factors included as design features. Field evaluations were conducted to identify factors responsible for the difference in the performance. Overall, 4-inch BCO provided good performance for the last 20 years. From the surveyed results, welded wire fabric showed better performance than steel fibers. Crushed limestone also provided better performance than siliceous river gravel. The combinations of steel fiber and siliceous river gravel did not perform as well. The conditions of pavements prior to overlay do not appear to have substantial effects on BCO performance.]]></description>
      <pubDate>Wed, 17 Jun 2009 12:07:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/890495</guid>
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    <item>
      <title>Best Practices for the Use of Siliceous River Gravel in Concrete Paving</title>
      <link>https://trid.trb.org/View/887694</link>
      <description><![CDATA[Fracture toughness (K sub IC) value at early ages of concrete was used to represent the interfacial bond between aggregate and mortar of a variety of coarse aggregates types and concrete mixtures. A fractional factorial design based on Taguchi’s orthogonal array using four factors (i.e., aggregate type, w/cm, replacement of ultra-fine fly ash, and curing method) was selected to conduct the detailed laboratory study. The statistical analysis indicated the following decreasing rank order with respect to the relative importance of each factor to K sub IC: aggregate type, curing method, w/cm, and ultra-fine fly ash content. A comprehensive investigation of aggregate properties relative to physical, geometric, and chemical characteristics was conducted. The research findings indicated that the aggregate-mortar interfacial bond for a given cement paste was found not to be a simple function of any one of the aggregate properties, but a function of all three properties aggregated together. The application of utility theory to the evaluation of overall contribution of aggregate properties to the bonding performance of concrete, and feasibility of design combinations enables agencies to select the best aggregate type, modify aggregates by blending different aggregates, and optimize the design combinations for concrete paving construction, to relieve delamination and further spalling distresses. The interfacial fracture energy can be predicted once a design combination is known based on the linear relation with both concrete and mortar fracture energy. A fracture mechanics based approach was proposed with the facilitation of numerical analysis to predict the occurrence of delamination. The criterion for predicting early age delamination occurrence is that delamination occurs when the stress intensity factor (K sub I) > K sub IC. Through examples of practical design and construction methods, this approach is able to assess the probability of delamination occurrence, which will facilitate selection and evaluation of the effectiveness of pavement design methods to prevent delamination and spalling problems in concrete paving. Test sections of both winter and summer were established based on the research finding from laboratory investigations, theoretical modeling, and numerical analysis. Future performance of these sections will determine if the measures taken to arrest delamination were successful or not.]]></description>
      <pubDate>Fri, 17 Apr 2009 15:57:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/887694</guid>
    </item>
    <item>
      <title>Evaluation of Bonded Concrete Overlay on IH 610 in Houston, Texas</title>
      <link>https://trid.trb.org/View/873788</link>
      <description><![CDATA[Bonded concrete overlays could provide cost-effective rehabilitation methods for structurally deficient portland cement concrete (PCC) pavements. Four-inch bonded concrete overlay (BCO) placed in 1986 on Houston’s IH 610 North has provided quite satisfactory performance for more than 20 years. Ten test sections were placed as a part of the BCO project during the construction, and after 20 years, they provide invaluable information on the long-term performance of BCO. The variables included in the test sections are reinforcement, coarse aggregate type, and existing pavement condition. The overall performance of 4-in. BCO has been excellent, even though there were a few patches made to address partial depth punchouts. Four-inch BCO over 8-in. continuously reinforced concrete pavement (CRCP) reduced deflections by about one-third, which is good evidence for BCO’s ability to enhance the structural capacity of under-designed PCC pavements. Between the two reinforcement types used, welded wire fabric and steel fibers, welded wire fabric provided better performance. It appears that welded wire fabric provided more effective restraint on concrete volume change potential, thus improving bonds between BCO and existing concrete. Two coarse aggregate types were used in the test sections: siliceous river gravel (SRG) and limestone (LS). For the comparable condition, LS provided better performance than SRG. This finding is consistent with the performance in new CRCP, where more spalling and mid-depth horizontal cracking problems occur in sections with SRG. The condition of existing pavement, at least as evaluated with the method adopted in this study, does not appear to have substantial effects on the performance of BCOs. Delaminations and resulting partial depth punchouts were the primary structural distresses. Delaminations were along longitudinal warping joints, as well as under the wheel paths. Those along the longitudinal warping joints appear to be due to environmental loading, while those under the wheel paths were due to wheel load stresses. Full saw cuts through BCO at longitudinal warping joints will minimize delaminations.]]></description>
      <pubDate>Tue, 25 Nov 2008 07:32:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/873788</guid>
    </item>
    <item>
      <title>Fiber in Continuously Reinforced Concrete Pavements</title>
      <link>https://trid.trb.org/View/811305</link>
      <description><![CDATA[Continuously reinforced concrete pavement (CRCP) is a major form of highway pavement in Texas due to its increase in ride quality, minimal maintenance, and extended service life. However, CRCP may sometimes experience pavement distress that results in early failure, either due to under-design or the use of poor construction materials. Significant effort has been made to improve the performance of some of these materials (e.g. siliceous river gravel) to achieve an acceptable level of performance but has been unable to provide a practical solution. This research study investigates whether fiber reinforcement may solve some of the problems associated with siliceous river gravel, particularly spalling. The main objectives of this study were to: (1) Conduct a comprehensive literature review in order to determine the current state of the art regarding CRCP design and behavior as well as the role that fiber reinforcement may have in improving its performance; (2) Perform field investigations in order to verify constructability and workability of fibers in CRCP construction; (3) Perform frequent monitoring to evaluate the effect of fibers on crack spacing, crack width, and spalling development; (4) Perform laboratory testing that validates the effect of fibers on typical concrete paving mixes; (5) Provide the Texas Department of Transportation with recommendations as to possible changes in the construction and design specifications of CRCP, which could serve to reduce or prevent spalling. Because the manifestation of spalling in CRCP may sometimes take several years, it is difficult to draw firm conclusions from this two-year study. However, based on the findings within the time frame of this project, fiber reinforcement did appear to prevent or limit spalling in the field test sections, when compared to the control sections that did not contain fibers. It is recommended that future monitoring of these test sections be performed to fully characterize the long-term efficacy of fibers in reducing or preventing spalling of CRCP.]]></description>
      <pubDate>Tue, 26 Jun 2007 14:32:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/811305</guid>
    </item>
    <item>
      <title>Long-Term Performance of Thin Bonded Concrete Overlay in Texas</title>
      <link>https://trid.trb.org/View/800894</link>
      <description><![CDATA[The Texas Department of Transportation (TxDOT) has many miles of old Portland cement concrete pavements (PCCP) that need rehabilitation due to their deficient structural capacity.  Bonded concrete overlay (BCO) presents one of the rehabilitation strategies to strengthen PCCP systems.  In 1986, TxDOT constructed a 4-inch BCO on existing continuously reinforced concrete pavement (CRCP) in Houston.  A factorial design was developed to evaluate the effects of different materials/design features and the condition of existing pavement.  Test sections were placed in accordance with the factorial experiment.  Materials included were siliceous river gravel and crushed limestone as coarse aggregates.  The use of welded wire fabric and steel fibers was the factors included as design features.  Overall, 4-inch BCO provided very good performance for the last 20 years.  Some sections have performed superbly without any distress, while some sections experienced surface distresses that required patching.  There were good correlations between materials/design features and performance.  Welded wire fabric provided better performance than steel fibers.  Crushed limestone also provided better performance than siliceous river gravel.  Sections with welded wire fabric and crushed limestone provided the best performance, with no single distress for the last 20 years.  Sections with welded wire fabric and siliceous river gravel performed very well.  The combinations of steel fiber and siliceous river gravel did not provide good performance.  The conditions of pavements prior to overlay do not appear to have substantial effects on BCO performance.  Based on the findings, efforts are under way in TxDOT to revise BCO design/material/construction practices.]]></description>
      <pubDate>Thu, 15 Mar 2007 06:42:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/800894</guid>
    </item>
    <item>
      <title>Performance of Porous Asphalt Concrete</title>
      <link>https://trid.trb.org/View/798296</link>
      <description><![CDATA[Because of its noise reducing capacity, porous asphalt concrete is commonly used nowadays in the Netherlands for wearing courses on highways. Traditionally a single layer of porous asphalt concrete (PAC) (gradation 6/16 mm) is applied with a thickness of 50 mm. Investigations however have shown that double layer PAC, consisting of a 30 mm top layer of fine graded (2/6 or 4/8 mm) PAC on top of 50 mm coarse graded (11/16 mm) PAC, have better noise reducing capabilities. These mixtures are therefore going to be used on a large scale on highways in densely populated areas. The lifetime of PAC shows a large variation and in order to keep the maintenance costs under control, measures are sought to extend the mean lifetime and to reduce the variation there in. More and more it is believed that the lifetime of PAC and its variation are strongly influenced by the construction process. A study was therefore undertaken to determine to what extent the development of the main defect type, being raveling, is determined by the composition of the mixture as laid and factors like traffic and climate. For this, the PAC sections in the SHRP-NL database were analyzed by means of Artificial Neural Network techniques (the SHRP-NL data base only contained information on single layer PAC). This study revealed that the quality of the mixture as laid has a very large influence on the performance of the mixture and it was shown e.g. that bitumen contents lower than 4% should not be accepted. Also siliceous river gravel should not be used. Furthermore a study was undertaken to determine to what extent the initial quality of single layer PAC was influenced by the working conditions. For this a particular paving job was intensively monitored and it appeared that the composition of the mixture as laid is highly variable. From the data an equation could be developed that relates the void content, being of PAC, to mixture composition, temperature of the mixture and compaction effort. Finally research was done on double layer PAC. This double layer offers a better reduction in traffic noise than the conventional single layer PAC but problems may arise with the permeability because of a low void content in the interface between top and bottom layer. It will be shown that selection of the gradation is of prime importance for noise reduction and permeability purposes and an optimal gradation for both layers will be proposed.]]></description>
      <pubDate>Tue, 30 Jan 2007 13:29:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/798296</guid>
    </item>
    <item>
      <title>Selection of Optimum Gravel Aggregate Size to Resist Permanent Deformation in Hot-Mix Asphalt</title>
      <link>https://trid.trb.org/View/777354</link>
      <description><![CDATA[Siliceous river gravels form a significant fraction of the different types of aggregates used in the construction of hot-mix asphalt (HMA) pavements. Even after gravel particles are crushed into smaller-size fractions, a significant proportion of the larger-size fractions retain their original shape and surface texture. As a result, HMA with a larger nominal maximum aggregate size (NMAS) has a higher percentage of rounded and low-angularity particles, which might make it more susceptible to rutting. Using a smaller NMAS may decrease the percentage of rounded and angular aggregates in the mix, but potentially at the expense of loss in shear strength of the mix. This study evaluated the effect of increasing aggregate angularity by decreasing NMAS on the rutting potential of HMA mixes containing siliceous gravels. Nine mix designs composed of three different NMASs and siliceous aggregates from three different sources were included in this study. The percentage of rounded and angular aggregates in each mix was quantified using image analysis and crushed-face count. The rutting potential of HMA mixes was assessed on the basis of Hamburg, dynamic modulus, flow time, and flow number tests. Results verify that a decrease in NMAS results in a decrease in the percentage of rounded and angular aggregates. However, rutting performance improves initially with a decrease in NMAS but then decreases; this indicates an optimum size that maximizes the rut resistance of HMA with siliceous aggregates. Results from this study are especially useful in selecting an optimum aggregate size for HMA mixes in locations where river gravels are the main source of locally available aggregates.]]></description>
      <pubDate>Thu, 29 Jun 2006 07:39:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/777354</guid>
    </item>
    <item>
      <title>Analysis of South Texas Aggregates for Use in Hot Mix Asphalt</title>
      <link>https://trid.trb.org/View/756699</link>
      <description><![CDATA[The primary locally available aggregates in the South Texas districts for highway construction are siliceous river gravels, which typically exhibit a rounded shape.  The warm South Texas climate combined with heavy truck traffic aggravates any rutting problems that may occur due to the use of low angularity aggregates in hot mix asphalt (HMA) paving mixtures.  The objective of this study was to determine the effect of aggregate angularity and nominal maximum size of siliceous aggregates on performance of selected HMA surface pavement mixtures.  The research approach was guided by the realization that engineers can use the results for mixture design, especially for South Texas districts.  Aggregates and mixture designs were obtained from the Corpus Christi, Laredo, and Pharr Districts.  The selected aggregates were characterized using image analysis, crushed face count, flat and elongated particles, and Micro-Deval tests.  Researchers assessed performance of the HMA based on the simple performance tests and the Hamburg test.  Comparison of aggregate properties with mixture performance yielded important information about optimal design of mixtures containing siliceous gravels.  These findings do not support the use of finer South Texas gravel mixtures (Type D and 9.5 mm) with more crushed faces in the coarse aggregate to maximize rutting resistance.  In fact, the finer mixes most often demonstrated the least rutting resistance in the simple performance tests.  A decrease in nominal maximum aggregate size (NMAS) may adversely affect HMA rutting resistance unless it is offset by improved aggregate shape characteristics.  Type C and 12.5-mm materials generally demonstrated the optimum rutting performance in the simple performance tests, however, the fine-graded 12.5-mm mixture performed poorly in the Hamburg test.  Cracking resistance of the mixes was not significantly affected by the change in NMAS.]]></description>
      <pubDate>Thu, 16 Jun 2005 16:49:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/756699</guid>
    </item>
    <item>
      <title>A FOLLOW-UP EVALUATION OF HOT-MIX PAVEMENT PERFORMANCE IN NORTHEAST TEXAS</title>
      <link>https://trid.trb.org/View/697091</link>
      <description><![CDATA[A task group was formed in late 1997 to evaluate the specifications and practices being used in northeast Texas districts in the construction of hot-mix asphaltic concrete pavements.  Specifically, the objective of that task group was to determine if the implemented recommendations from a 1995 task group were effective in improving the performance of crushed gravel asphaltic pavements in that area of the state.  The task group selected and evaluated the performance of 35 pavements constructed using a wide variety of materials over the prior nine years.  Seven of the pavements had been constructed in 1997, some of which had incorporated a number of the earlier task group recommendations.  Pavement performance evaluations in early 1998 included a visual distress survey, ground-penetrating radar analysis, pavement management information system data, and testing and visual evaluation of pavement cores.  The early age of pavements evaluated in the spring of 1998 prevented a definitive determination of the long-term performance of northeast Texas asphalt pavements.  Therefore, the task force recommended evaluation of the performance of these sections in three years.  In the spring of 2001 the task force was reconvened to conduct the follow-up study on the 35 pavements evaluated in 1998.  The task force was composed of personnel from Atlanta, Tyler, and Lufkin districts as well as representatives from Design and Construction Divisions, the Research and Technology Implementation Office, Texas Transportation Institute, and two consultants.  The study presented in this report indicates that many of the recommendations implemented in 1997 by the Atlanta District have resulted in improved pavement performance.  Utilization of hydrated lime as an antistripping additive appears to have a positive influence on performance of the mixtures containing crushed siliceous river gravel.  It is recommended that the findings of the 1995 task group be considered for implementation by all districts that use crushed siliceous river gravel in hot mix.]]></description>
      <pubDate>Fri, 30 Apr 2004 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/697091</guid>
    </item>
    <item>
      <title>IMPORTANCE OF CONCRETE TEMPERATURE CONTROL DURING CONCRETE PAVEMENT CONSTRUCTION IN HOT WEATHER CONDITIONS</title>
      <link>https://trid.trb.org/View/731928</link>
      <description><![CDATA[The development of high concrete temperatures could cause a number of effects that have been shown to be detrimental to long-term concrete performance.  High concrete temperatures increase the rate of hydration, thermal stresses, the tendency for drying shrinkage cracking, and permeability and decrease long-term concrete strengths and durability as a result of cracking.  Data from the Texas Rigid Pavement database were analyzed to reveal whether there are increased numbers of failures as the air temperature at placement increases. It was shown that this was the case for both major coarse aggregate types: limestone and siliceous river gravel.  The results of the analysis emphasize the importance of concrete temperature control during concrete pavement construction in hot weather conditions.  Most states specify a maximum concrete temperature at placement to mitigate the detrimental effects of placement during hot weather.  The specified limit remains the same irrespective of the type of mineral or chemical admixtures used. To produce specifications that encourage contractor innovation and the use of improved materials, modern specifications should account for these materials to ensure improved concrete performance under all placement conditions.  To provide improved performance for sections paved under hot weather conditions, it is proposed that the continuously reinforced concrete pavement reinforcement standards be redesigned to provide steel quantities for specific use during hot weather conditions and that an end-result specification that limits the maximum in-place concrete temperature during hydration be implemented.]]></description>
      <pubDate>Tue, 14 Jan 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/731928</guid>
    </item>
    <item>
      <title>EVALUATION OF THE EFFECT OF COARSE AGGREGATE TYPE ON CRCP THICKNESS</title>
      <link>https://trid.trb.org/View/716179</link>
      <description><![CDATA[The significant effect of the coarse-aggregate type (CAT) on the performance of concrete pavements has not been fully accounted for in the design-construction process. Among the main properties of concrete that vary with CAT are the modulus of elasticity, the coefficient of contraction and expansion, and tensile strength; these properties, in turn, influence the performance of concrete pavements. However, the selection of CAT is often left to the contractor without having evaluated the consequences of using an aggregate whose properties were not considered during the design stage. To illustrate the variation of CRCP performance with the 2 CATs most often used Texas (crushed limestone and siliceous river gravel), typical values of the physical properties of concrete produced with these 2 aggregates were selected from lab results. Three different approaches were used to estimate thickness equivalencies between limestone and siliceous river gravel CRCPs and are described. Results of theoretical analyses from this research indicate that, for the 2 CATs tested, generally less distress was observed in limestone CRCP. Findings developed could be used to determine approximate equivalent thicknesses for the 2 aggregate types considered here if there is no need for detailed analysis. By using recommended thickness equivalencies, the designer has enough information to estimate costs of construction of a CRCP section when permitted to employ either limestone or siliceous river gravel coarse aggregate.]]></description>
      <pubDate>Mon, 21 Jan 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/716179</guid>
    </item>
    <item>
      <title>EARLY AGE PERFORMANCE OF CONTINUOUSLY REINFORCED CONCRETE PAVEMENT WITH DIFFERENT TYPES OF AGGREGATE</title>
      <link>https://trid.trb.org/View/576097</link>
      <description><![CDATA[The effect of coarse aggregate on pavement performance has been attributed to the volume of aggregate used in pavement construction.  The different patterns of crack development for limestone (LS) and siliceous river gravel (SRG) are a typical example of aggregate-induced variable performance in continuously reinforced concrete pavement (CRCP).  An attempt was made to find a reasonable solution for pavements with SRG. As a way to solve the performance problem observed from the SRG pavement, a blended aggregates mixture was suggested. Laboratory and field tests were performed to check the feasibility of their application in pavements.  From the laboratory test, a 50:50 blending ratio was suggested after considering the effect on tensile strength and thermal coefficient of expansion.  Field test sections were also constructed to verify previous performance observations for the two aggregates and to provide performance data for new variables such as blended aggregates and special curing methods. Unexpectedly, the blended mixture did not improve the performance of SRG pavement; rather it experienced worse cracking than SRG alone.  A controlled experiment with additional field test sections is needed to verify or disprove this finding.  The only definitive finding was that selection of aggregate in the concrete pavement is a vital consideration for the design of the pavement.  The CRCP8 analytical program reasonably predicted crack spacing for both SRG and LS pavements, predicting mean crack spacing of 0.99 m (3.25 ft) for SRG and 1.98 m (6.41 ft) for the limestone.  These values are somewhat below the actual spacing observed at 100 days.  Data collected after the first winter period will be required to calibrate the program.]]></description>
      <pubDate>Mon, 25 Aug 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/576097</guid>
    </item>
    <item>
      <title>EFFECT OF AGGREGATES ON PAVEMENT PERFORMANCE. FINAL REPORT</title>
      <link>https://trid.trb.org/View/454659</link>
      <description><![CDATA[In Texas, rigid (or portland cement concrete) pavements and flexible (or asphaltic concrete) pavements are most often constructed using crushed limestone and/or siliceous river gravel as the coarse aggregate.  Project 1244, sponsored by the Texas Department of Transportation (TxDOT), evaluated the performance of rigid pavements and flexible pavements made with siliceous river gravel and with crushed limestone as coarse aggregates, in order to develop specifications that obtain equal and adequate performance from the different aggregates.]]></description>
      <pubDate>Wed, 24 Apr 1996 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/454659</guid>
    </item>
    <item>
      <title>EFFECTS OF AGGREGATE BLENDS ON THE PROPERTIES OF PORTLAND CEMENT CONCRETE PAVEMENTS. INTERIM REPORT</title>
      <link>https://trid.trb.org/View/421340</link>
      <description><![CDATA[Although recent studies have shown that pavement performance does vary by aggregate type, current portland cement concrete pavement design tools do not fully incorporate aggregate properties into the design process.  Aggregate characteristics shown to affect pavement performance include strength, thermal properties, and shrinkage properties.  The objective of this study was to investigate the material properties of crushed limestone and siliceous river gravel, two aggregates predominantly used in current pavement construction, and to determine a relationship between the properties of single-aggregate concrete and concrete made with predetermined blends of limestone and gravel.  This report continues the work of Project 422/1244, which way limited to single-aggregate concretes.  Additional models were developed to predict concrete properties of blended aggregate concrete for use in the design tools, CRCP and JRCP, described in previous 422/1244 reports.  A computer program, CHEM2, was developed, which allows the pavement designer to estimate the material properties of concrete from an inexpensive chemical test.  CHEM2 also predicts the properties of blended aggregates so that the user can determine the necessary blending ratio to control such troublesome properties as thermal coefficient of expansion and drying shrinkage.]]></description>
      <pubDate>Mon, 17 Apr 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/421340</guid>
    </item>
    <item>
      <title>MONITORING OF SILICEOUS RIVER GRAVEL AND LIMESTONE CONTINUOUSLY REINFORCED CONCRETE PAVEMENT TEST SECTIONS IN HOUSTON 2 YEARS AFTER PLACEMENT, AND DEVELOPMENT OF A CRACK WIDTH MODEL FOR THE CRCP-7 PROGRAM. INTERIM REPORT</title>
      <link>https://trid.trb.org/View/368017</link>
      <description><![CDATA[In describing the effect of coarse aggregate type on the performance of CRCP, this report documents the design, construction, and monitoring of 32 test sections in Houston, Texas.  Constructed to evaluate the performance of pavements built in accordance with the CRCP-89(B) design detail recently developed by TxDOT, these test sections were monitored to determine the field performance of CRCP 2 years after construction, looking in particular at crack spacings and crack width.  Then, using the observed performance of the different coarse aggregates, the study team evaluated the recently developed CRCP-89(B) design detail.  Finally, using the CRCP-7 computer program, the predicted performance was compared with the measured performance of the CRCP test sections.  Based on this comparison, a new model to be used with the CRCP-7 program -- one capable of predicting crack widths -- was developed.]]></description>
      <pubDate>Thu, 16 Dec 1993 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/368017</guid>
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