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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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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>Designing Mixes for Top Performance</title>
      <link>https://trid.trb.org/View/1322281</link>
      <description><![CDATA[This article familiarizes readers with some of the design mixes that can be used for top pavement performance.  The author notes that pavement engineers have a wealth of materials from which to choose, including dense-graded mixes, open-graded (permeable) mixes, stone matrix asphalts (SMAs), and mixes with various reclaimed components and numerous modifiers.  The author covers the purpose of mix design, the steps involved in designing a mix, mix designs that use high amounts of reclaimed asphalt pavement (RAP), the Bailey Method of assessing aggregate particles, performance testing, and different types of cracking that may occur.  Performance testing, which evaluates rutting and cracking of the pavement, can including the Marshall stability and Hveen stabilometer tests, loaded wheel testing (LWT), the Hamburg wheel-tracking test, and the Asphalt Mixture Performance Test (flow number test).   Readers are referred to the Asphalt Institute for more detailed resources about pavement mixes.]]></description>
      <pubDate>Fri, 26 Sep 2014 14:43:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/1322281</guid>
    </item>
    <item>
      <title>Using critical state theory for modelling of asphalt mix compaction</title>
      <link>https://trid.trb.org/View/1307167</link>
      <description><![CDATA[This paper focuses on modeling of Hot Mix Asphalt (HMA) material behavior during compaction. During compaction the particle configuration inside the HMA is changing from a relatively loose into a denser one while the bitumen is fluid. Initially particle reorientation is easily possible due to the HMA's loose configuration. The material behavior predominantly falls in the elastic-plastic domain. Critical state theory from soil mechanics is proposed as a basis for modeling this behavior. An extensive laboratory testing program was undertaken using a modified Hveem stabilometer as a tool for parameterization. The program included: different mixtures, different stages of mixture density and different material temperatures. In this paper, the authors discuss how well the critical state principles suit HMA behavior, and what the critical state material parameters are for HMA with respect to different material temperatures, different compaction stages and different stress states. They show that HMA compaction behavior can be modeled using the critical state theory and that material behavior is bi-linear in the p':q stress space.]]></description>
      <pubDate>Tue, 27 May 2014 09:41:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/1307167</guid>
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    <item>
      <title>Stability Relationships Of Gyratory-Compacted Bituminous Mixtures</title>
      <link>https://trid.trb.org/View/1219276</link>
      <description><![CDATA[A laboratory study was made of the stability relationships of bituminous mixtures compacted in the gyratory testing machine. Compaction in the gyratory testing machine was imposed on the bituminous mixtures in an attempt to simulate compaction that would be imposed by construction and traffic compaction. The study consisted, in part, of stability measurement of specimens compacted under varying levels of simulated construction and traffic compaction. Two aggregate gradations were used to study the effects of compaction on dense- and open-graded mixtures. Compactive effort was varied by changing ram pressure and number of revolutions as well as type of operation in the gyratory testing machine. Stability measurements were made with the Hveem stabilometer.  Statistical analyses were used to evaluate the effect of each of the variables on specimen stability. The results of the study indicated that the load imposed on specimens during the course of the stabilometer test increased density and decreased voids in some compacted specimens.]]></description>
      <pubDate>Tue, 11 Dec 2012 11:56:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/1219276</guid>
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    <item>
      <title>Application of the Kneading Compactor and Hveem Stabilometer to Bituminous Concrete Design in Indiana</title>
      <link>https://trid.trb.org/View/1219374</link>
      <description><![CDATA[This study was undertaken with the intention of indicating a suitable Hveem design procedure to be employed in the design of Indiana bituminous mixtures under heavy traffic conditions. The study had two major purposes t l) to study the validity of using the present Hveem design method, as employed by the California Highway Department, for design of Indiana surface and binder mixtures, and 2) if some modification of the standard California, procedure was indicated for Indiana surface and binder mixtures, the laboratory compaction pressure would be altered until test results for field and laboratory specimens were in substantial agreement. The study required sampling of bituminous pavements by taking 4-in. diameter cores and performing a laboratory correlation. Marshall tests were made on composite samples for four samplings over a five-year period and Hveem tests were made on composite and individual-course samples for the final sampling in 1959. A mechanical kneading compactor was used for fabricating laboratory specimens with mixture properties comparable to the properties for cored specimens taken from the pavements, and samples of each mixture were also compacted with the Marshall hammer and tested for further information. The Hveem Stabilometer and Marshall stability machine were used for measuring the strength of both field and laboratory specimens. Mixture void contents were measured for field and laboratory-compacted specimens using Rice specific gravity values. Aggregate degradation was studied in a very limited way by comparing aggregate gradations and the percent of mix retained on the No. 6 sieve, for field-compacted samples and laboratory-compacted samples, to the original aggregate gradation used at the time of construction. Tests were also made to determine the effect of kneading compaction on specimen uniformity by determining density, asphalt content, and aggregate degradation variation throughout compacted specimens. Pavement cores were recompacted using the kneading compactor and the standard compaction procedure in an effort to reproduce field density and Hveem stability values. It is concluded from this study that, generally, the normal 500 psi compaction pressure can be used for Indiana binder mixtures, but a lower design compaction pressure should be employed for compacting more sensitive mixtures. These sensitive mixtures are usually surface mixtures, especially those surface mixtures containing high percentages of crushed limestone aggregate and a high asphalt content.]]></description>
      <pubDate>Fri, 30 Nov 2012 08:56:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1219374</guid>
    </item>
    <item>
      <title>The Effect of Density on the Repeated-Load Strength Properties of Bituminous Concrete</title>
      <link>https://trid.trb.org/View/1219389</link>
      <description><![CDATA[This study is concerned primarily with the plastic deformations obtained through the repeated-load testing of bituminous concrete surfacing mixtures. Parameters were calculated from these plastic deformations and were compared with results from the Hveem Stabilometer test. In the initial part of this investigation an attempt was made to obtain a slab-type specimen which would produce realistic results by the repeated-load test. Since means were not found to compact a slab-type specimen to a uniformly high density, a cylindrical-type specimen was used as an alternative for the repeated-load test. In comparing the results of the repeated-load test with the Hveem Stabilometer test results, it appears that the mixtures are evaluated differently by the two methods. The results from this investigation are not suitable for evaluating bituminous concrete surface mixtures in regard to rutting and shoving.]]></description>
      <pubDate>Fri, 30 Nov 2012 08:56:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1219389</guid>
    </item>
    <item>
      <title>Application of the Hveem Stabilometer to the Testing of Open-Graded Bituminous Mixtures</title>
      <link>https://trid.trb.org/View/1219381</link>
      <description><![CDATA[This laboratory investigation was conducted with the purpose of determining the applicability of the Hveem Stabilometer to the testing of open-graded bituminous mixtures.The study was divided into two major sections. The first of these investigated the validity of the Stabilometer displacement measurement when applied to open-graded specimens having large surface air voids. The second portion of the study had two specific purposes: (l) to investigate the stress-strain characteristics of open-graded mixtures tested in the Hveem Stabilometer and (2) to determine whether surface voids on the ends of Stabilometer test specimens influenced Hveem stability values.To check the validity of the displacement measurement, Stabilometer tests were, conducted over a wide range of displacement values for duplicate specimens molded from three different mixtures. Displacement readings were varied by altering the surfaces of test specimens and by adjusting the quantity of air inside the Stabilometer oil chamber. In studying the stress-strain characteristics of open-graded mixes, Stabilometer values and specimen deformation readings were obtained for two mixtures. The first of these open-type mixes was well-graded, but the second was essentially "one-sized" in gradation. Results of this investigation showed that the final displacement value, when substituted into the Hveem stability equation, did not compensate for the variations in lateral pressure caused by large changes(one or more turns) in the final displacement measurement. Stress-strain relationships for the well-graded, open-type mixture indicated that the quantity of strain permitted a Stabilometer test specimen conformed closely with the amount of strain developed at the maximum shearing strength of a rational triaxial test specimen subjected to confining pressures similar to those present in a Stabilometer test. Strain measurements recorded for Stabilometer specimens of the one-sized mixture used in this study were much lower than those obtained at the peak value of shearing resistance for triaxial test specimens of the same mixture and for similar confining pressures. Surface air voids on the ends of Stabilometer test specimens had a small effect on test results. When these voids were filled, Hveem stability values were not significantly higher, but the reproducibility of test results was greatly improved by coating test specimens. To improve the consistency of Stabilometer test results obtained from open-graded mixtures, certain modifications in the testing technique were suggested. These changes involved the filling of air voids on the surface of test specimens and the admittance of an increased amount of air in the Stabilometer oil chamber during the calibration of the testing apparatus.]]></description>
      <pubDate>Fri, 30 Nov 2012 08:56:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1219381</guid>
    </item>
    <item>
      <title>JHRP-ISHD Cooperative Study Using Kneading Compactor and Hveem Stabilometer</title>
      <link>https://trid.trb.org/View/1219330</link>
      <description><![CDATA[This is the final report of results of a cooperative study using a kneading compactor and Hveem Stabilometer done between the Indiana State Highway Department and Joint Highway Research Project bituminous laboratories. The final phase of the Purdue work is presented in the first section. The sections following present comparisons of the data obtained in the two laboratories for the final phase of the program in which a type B surface gradation was used. Comparisons are made by presenting average test values in tabular form, by graphical illustrations, and by statistical evaluation of the data. Conclusions and recommendations are presented.]]></description>
      <pubDate>Mon, 19 Nov 2012 10:08:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/1219330</guid>
    </item>
    <item>
      <title>Testing Open-Graded Bituminous Mixtures in the Hveem Stabilometer : Technical Paper</title>
      <link>https://trid.trb.org/View/1219398</link>
      <description><![CDATA[The problem of designing stable bituminous paving mixtures has resulted in the development of a number of laboratory stability tests. One of the more prominent of these was originated by Francis N Hveem and has been used by the California Division of Highways for several years. In the past, most of the bituminous mixtures tested in the Hveem Stabilometer have been of the dense-graded type (22). Consequently, the significance of Stabilometer test results obtained from the testing of open-graded mixtures is subject to some question. Since the use of the open-graded mixes has been quite widespread, especially in the State of Indiana, a laboratory investigation was conducted at Purdue University which attempted to determine the applicability of the Stabilometer to the testing of these mixtures. This paper reports a portion of the results obtained from that study.]]></description>
      <pubDate>Thu, 15 Nov 2012 14:02:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1219398</guid>
    </item>
    <item>
      <title>A Practical Look at the Simple Performance Tests: Louisiana's Experience (With Discussion)</title>
      <link>https://trid.trb.org/View/776094</link>
      <description><![CDATA[The Superpave volumetric mix design procedure developed during the Asphalt Research Program of the Strategic Highway Research Program did not include a mechanical “proof” test similar to the ones commonly used in the Marshall mix design or Hveem mix design such as the Marshall stability and flow tests or the Hveem stabilometer method, respectively. The Superpave mix design method, however, did use strict requirement to material specifications and volumetric mix criteria to ensure satisfactory performance of mix designs that were intended for low volume traffic. In addition, the original Superpave mix design protocol required mix verification for intermediate and high volume traffic through advanced materials characterizations tests utilizing the Superpave Shear Tester test protocols. It was quickly recognized the complexity of those test protocols for routine mix design application and that a simple performance test is needed to complement the Superpave volumetric mix design procedure. In response to this need, National Cooperative Highway Research Program (NCHRP) Project 9-19, Superpave Support and Performance Models Management, recently recommended three candidate Simple Performance Tests (SPTs) to complement the Superpave volumetric mixture design method. These are flow time (FT), flow number (FN), and dynamic modulus |E*| tests. In addition, the dynamic modulus test was selected for the hot mix asphalt (HMA) materials characterization input utilized in the 2002 Empirical and Mechanistic Guide for Design of New and Rehabilitated Pavement Structures, developed under NCHRP Project 1-37A. This paper presents a practical look at the results of a cooperative evaluation of similar Superpave mixtures utilizing two tests of the SPTs: the Dynamic Modulus and Flow Number. Two different dynamic modulus predictive models, Witczak and Hirsch, were also evaluated.]]></description>
      <pubDate>Mon, 27 Mar 2006 11:07:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/776094</guid>
    </item>
    <item>
      <title>RELATIONSHIP BETWEEN DENSITY AND STABILITY OF SUBGRADE SOILS</title>
      <link>https://trid.trb.org/View/122592</link>
      <description><![CDATA[THIS PAPER DISCUSSES SOME OF THE LIMITATIONS OF THE CONCEPTS THAT THE STABILITY OF A COMPACTED SOIL INCREASES WITH AN INCREASE IN DENSITY AND THAT EVERY EFFORT SHOULD BE MADE TO ATTAIN THE HIGHEST PRACTICAL DENSITY IN FIELD COMPACTION. COMPREHENSIVE TEST DATA ON THE RELATIONSHIP BETWEEN DENSITY, STABILITY, WATER CONTENT, AND DEGREE OF SATURATION FOR TWO SOILS COMPACTED BY KNEADING ACTION ARE PRESENTED, TOGETHER WITH A DESCRIPTION OF THE TRIAXIAL INSTITUTE KNEADING COMPACTOR. IN THE TESTS, STABILITY IS MEASURED BY TRIAXIAL-COMPRESSION TESTS AND BY THE HVEEM STABILOMETER. THE SIGNIFICANCE OF THE CRITERION OF STABILITY ADOPTED WITH RESPECT TO THE RELATIONSHIP BETWEEN DENSITY AND STABILITY IS DISCUSSED. THE RELATIONSHIP BETWEEN THE ATTAINABLE STABILITIES AND THOSE DETERMINED BY SPECIFICATIONS BASED ON THE STANDARD PROCTOR AND MODIFIED AASHO COMPACTION TESTS IS DEMONSTRATED. DATA ARE ALSO PRESENTED ON THE DENSITY-VERSUS-STABILITY RELATIONSHIPS OF SOILS COMPACTED BY IMPACT AND STATIC PROCEDURES, AND THE EFFECT OF COMPACTION METHOD ON THE DENSITY-VERSUS-STABILITY RELATIONSHIP IS SHOWN. THE CONFLICTING CONCLUSIONS WHICH MAY BE REACHED ON THE BASIS OF TESTS ON SAMPLES PREPARED BY STATIC AND IMPACT METHODS OR BY STATIC AND KNEADING METHODS ARE INDICATED. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:44:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/122592</guid>
    </item>
    <item>
      <title>DETERMINATION OF MODULUS OF SOIL REACTION FROM STANDARD SOIL TESTS</title>
      <link>https://trid.trb.org/View/121421</link>
      <description><![CDATA[IN 1942, SPANGLER PRESENTED AN EQUATION FOR DETERMINING THE DEFLECTION OF FLEXIBLE METAL PIPE EMBEDDED IN SOIL. THE FORMULA INVOLVED A SOIL MODULUS CALLED THE MODULUS OF SOIL REACTION. TO DATE, NO PRACTICAL MEANS HAVE BEEN PRESENTED FOR DETERMINING THIS MODULUS FOR DESIGN PURPOSES. THE OBJECTIVE OF THIS RESEARCH PROGRAM WAS TO FIND A CORRELATION BETWEEN THE MODULUS OF SOIL REACTION (E') AND THE RESULTS OBTAINED FROM THE CBR TEST, HVEEM'S STABILOMETER TEST AND STANDARD SOIL PROPERTIES SUCH AS DENSITY, COMPACTION, MOISTURE CONTENT, AND PLASTICITY INDEX. THE THEORY OF ELASTICITY WAS USED TO DETERMINE THE RELATIONSHIP BETWEEN E' AND THE CBR VALUE. LABORATORY TESTS SHOW THAT THE RELATIONSHIP OBTAINED YIELDS RESULTS SATISFACTORY FOR MOST DESIGN SITUATIONS. SUGGESTED DESIGN VALUES BASED ON THE CBR TEST ARE ALSO GIVEN. THE RELATIONSHIP BETWEEN E' AND THE R- VALUE DETERMINED FROM HVEEM'S STABILOMETER TEST WAS DETERMINED BY USING AN EMPIRICAL CORRELATION PRESENTED BY THE CALIFORNIA DIVISION OF HIGHWAYS BETWEEN THE R-VALUE AND THE PLATE-BEARING TEST. THE THEORY OF ELASTICITY WAS THEN USED TO RELATE THE PLATE-BEARING TEST TO THE MODULUS OF SOIL REACTION. SLIGHT EMPIRICAL ADJUSTMENTS HAD TO BE MADE IN THE CALIFORNIA CORRELATION; HOWEVER, LABORATORY RESULTS INDICATE A SATISFACTORY CORRELATION. FOR THE SITUATION WHERE THE INSTALLATION IS TO BE SMALL AND LABORATORY TESTS SUCH AS THE ONES JUST DESCRIBED ARE NOT FEASIBLE, THE MODULUS OF SOIL REACTION HAS BEEN RELATED TO RELATIVE COMPACTION OF THE SOIL. OTHER ITEMS INCLUDED IN THE DIMENSIONAL ANALYSIS WERE UNIT WEIGHT, PLASTICITY INDEX, MOISTURE CONTENT AND THE DIFFERENCE IN DENSITY BETWEEN THE AASHO DESIGNATION T180 AND T99 STANDARD COMPACTION TESTS. THE RESULTS OF THE STUDY INDICATE THAT APPROXIMATE VALUE FOR THE MODULUS OF SOIL REACTION CAN BE OBTAINED FROM A SIMPLE COMPACTION TEST. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:39:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/121421</guid>
    </item>
    <item>
      <title>A CORRELATION STUDY OF CALIFORNIA R-VALUE AND AASHO GROUP INDEX FOR ARKANSAS SOILS</title>
      <link>https://trid.trb.org/View/119358</link>
      <description><![CDATA[THIS IS THE FINAL REPORT ON THE FIRST PHASE OF THE RESEARCH STUDY ENTITLED ADAPTATION OF THE AASHO ROAD TEST EQUATION TO ARKANSAS CONDITIONS. THE OVERALL OBJECTIVE OF THIS PHASE OF THE STUDY IS TO INVESTIGATE THE POSSIBILITY OF OBTAINING THE AASHO SOIL SUPPORT VALUE FROM THE GROUP INDEX OF REPRESENTATIVE ARKANSAS SOILS. THE SPECIFIC OBJECTIVES ARE /1/ TO DETERMINE THE RELATIONSHIP BETWEEN R-VALUE AND THE GROUP INDEX AND /2/ TO EVALUATE THE RELATIONSHIPS OBTAINED. THE AASHO CLASSIFICATION, THE GROUP INDEX AND THE R-VALUE AT 240 P.S.I. EXUDATION PRESSURE WERE OBTAINED FOR EACH OF 159 SAMPLES SELECTED AT RANDOM FROM 21 OF 75 COUNTIES. THE FOLLOWING ANALYSES WERE MADE' /1/ CORRELATIONS BETWEEN R-VALUE AND THE GROUP INDEX USING SEVERAL DIFFERENT MATHEMATICAL MODELS, /2/ CORRELATIONS BETWEEN R-VALUE AND CERTAIN GRADATION AND PLASTICITY CHARACTERISTICS OF THE PLASTIC SOILS, AND /3/ CORRELATIONS BETWEEN R-VALUE AND CERTAIN GRADATION CHARACTERISTICS OF THE NONPLASTIC SOILS. CONFIDENCE LIMITS FOR THE R-VALUE-GROUP INDEX CORRELATIONS WERE DETERMINED. COMPARISONS OF THE ACTUAL /MEASURED/ R-VALUES WITH THOSE ESTIMATED FROM THE RELATIONS DEVELOPED FOR PLASTIC AND FOR NONPLASTIC SOIL ARE PRESENTED. THE AUTHORS CONCLUDE THAT THE GROUP INDEX IS NOT A RELIABLE PREDICTOR OF R-VALUE. THEY RECCOMMEND THAT USE OF THE GROUP INDEX AS A BASIS FOR DESIGN BE CONTINUED ONLY WITH EXTREME CAUTION AND THAT THIS PRACTICE CEASE AS SOON AS POSSIBLE. /BPR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:18:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/119358</guid>
    </item>
    <item>
      <title>FIELD EVALUATION OF A PORTABLE GYRATORY COMPACTOR</title>
      <link>https://trid.trb.org/View/718627</link>
      <description><![CDATA[Application of quality management concepts to asphalt paving evolved because recipe specifications frequently proved inadequate for ensuring pavement performance. Quality management of asphalt concrete is founded on the premise that the producer controls the end-quality of the product, including the in-place void content on which pavement performance is highly dependent. In its quality management program the Oregon Department of Transportation (ODOT) originally used the Marshall hammer, since neither the Hveem (kneading) nor Superpave prototype compactor was suitable for field quality control/assurance (QC/QA). Post-SHRP research led to the development of truly portable gyratory compactors, ie, those of 70 kg to 140 kg mass. Although selecting and proportioning materials as well as compaction are integral parts of the Superpave technology, there is some apprehension given the fact that no strength test is required at low traffic levels. Given ODOT's long and successful use of the Hveem method of mix design, the primary objective of this research was to assess the effectiveness of a portable gyratory compactor for field quality control purposes. A secondary objective was to determine the quality of Superpave mixes as measured by Hveem stability. To achieve these objectives plant-produced material was sampled during construction and compacted with both portable and prototype gyratory compactors. Shortly after construction, cores were extracted. All samples (gyratory compacted and field cores) were subsequently tested in the Hveem stabilometer. The following conclusions are noteworthy: Overall, the operational characteristics of the portable gyratory, including calibration and maintenance, were satisfactory. There was essentially no difference between the portable and prototype gyratory compactors as measured by air void content of 150 mm samples. In no case was the difference in air void content greater than 0.5 percent. Comparison of 100 mm and 150 mm samples compacted in the prototype gyratory was instructive in that the latter were consistently lower in air void content, typically by 0.5 to 1.5 percent. The air void content of plant mix samples compacted to Ndesign gyrations was consistently lower than that of the field cores, generally by at least 2 percent. The range in air void content of plant mix samples compacted to Ndesign gyrations was 3.0 to 8.8 percent, whereas the range in air void content of the field cores was 6.8 to 9.1 percent. The data indicate that there is virtually no difference in air void content between 100 mm and 150 mm field cores. Field cores generally had lower stabilities than did gyratory-or kneading-compacted samples. However, there was virtually no difference in the stability of lab compacted samples, regardless of gyratory type or specimen diameter. None of the field cores, regardless of project, met ODOT's minimum Hveem stability criterion of 35.]]></description>
      <pubDate>Mon, 15 Jul 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/718627</guid>
    </item>
    <item>
      <title>TESTING OF ASPHALT-RUBBER AND AGGREGATE MIXTURES</title>
      <link>https://trid.trb.org/View/144231</link>
      <description><![CDATA[This report is concerned with the development of a mixture design procedure for asphalt-rubber and aggregate. The investigation was aimed at finding a method for (a) mixing the high-viscosity asphalt-rubber with aggregate, (b) forming of test specimens made with the resilient material, and (c) testing the specimens obtained from compaction of the mixtures. Each of the above factors is discussed along with the test results obtained for Hveem stability, Hveem cohesiometer value, axial tension, double-punch tension and dynamic modulus of elasticity, and double-punch durability. In general, it was found that a normal high shear rate mechanical mixing procedure yielded good aggregate coating; tamping foot (T.I.) compaction was not possible; specimens compacted by static double plunger and also by vibratory-kneading procedures required three days of aging in the mold; specimens had high air void contents; 140 F (60 C) testing temperature was not feasible, and field trials will be needed to establish design criteria for laboratory prepared specimens. Durability measurements indicated the critical need of clean aggregates and high asphalt content.]]></description>
      <pubDate>Mon, 22 Apr 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/144231</guid>
    </item>
    <item>
      <title>HOT-MIX PAVEMENT STABILITY PERFORMANCE VERSUS LABORATORY TEST RESULTS</title>
      <link>https://trid.trb.org/View/267672</link>
      <description><![CDATA[The problem to be addressed by this study was to determine what characteristics of the Item 340 hot-mix material itself and its production, placement and service environments were significant in determining how well the hot-mix surface layer would function in the field.  SDHPT districts were asked for submission of well and/or poorly performing candidate pavements from a rutting or shoving distress standpoint.  In all, 18 separate locations or sites were included in this study.  The following types of data were obtained from these sites: (1) doing visual evaluations and taking rut depths on the surface, (2) taking roadway cores for subsequent laboratory testing.  Also a records search was made to determine pertinent facts affecting each roadway site from hot-mix design through production, laydown, compaction and service history of the roadway surface.  In general, the more rutted pavements contained softer asphalts, lower air voids and more temperature susceptible asphalts.  Indirect tensile strengths and Marshall stabilities tend to be lower for the more rutted pavements. The more rutted pavements tend to have grading curves with the higher humps avove the No. 30 sieve of the ASTM continuous grading curv.  Hveem stability appears to be no indication of rutting as found in this study.  (Author) study.  (Author)]]></description>
      <pubDate>Wed, 31 May 2000 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/267672</guid>
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