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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=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7Umhlb2xvZ2ljYWwgc3R1ZGllcyZxdW90OyIgb3JpZ2luYWxfdmFsdWU9IiZxdW90O1JoZW9sb2dpY2FsIHN0dWRpZXMmcXVvdDsiIC8+PC9maWx0ZXJzPjxyYW5nZXMgLz48c29ydHM+PHNvcnQgZmllbGQ9InB1Ymxpc2hlZCIgb3JkZXI9ImRlc2MiIC8+PC9zb3J0cz48cGVyc2lzdHM+PHBlcnNpc3QgbmFtZT0icmFuZ2V0eXBlIiB2YWx1ZT0icHVibGlzaGVkZGF0ZSIgLz48L3BlcnNpc3RzPjwvc2VhcmNoPg==" 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>EVALUATION OF SOIL COMPACTION BY RHEOLOGICAL TECHNIQUES</title>
      <link>https://trid.trb.org/View/121825</link>
      <description><![CDATA[THE ULTIMATE OBJECTIVE OF THIS STUDY IS TO FIND A QUANTITATIVE METHOD OF EVALUATING COMPACTION WHICH WILL AID HIGHWAY TECHNOLOGISTS TO: /1/ EVALUATE THE EFFICIENCY OF ROAD COMPACTION MACHINES, /2/ SELECT THE APPROPRIATE EQUIPMENT FOR A GIVEN MATERIAL, /3/ CHOOSE THE BEST COMPACTION PROGRAM FOR THE SPECIFIED DENSIFICATION OF A SOIL . THE OBJECT OF THE FIRST PHASE OF THIS STUDY WAS TO DETERMINE WHAT BASIC CHARACTERISTICS OF SOILS MUST BE USED TO SPECIFY DESIRED COMPACTION CORRECTLY. THE DENSIFICATION OF SOILS WAS STUDIED FROM A RHEOLOGICAL POINT OF VIEW USING DATA FROM LABORATORY TESTS. THE PLAN OF THIS STUDY WAS TO DESCRIBE THE MECHANICAL PROPERTIES OF HIGHWAYS SUBGRADE AND SUBBASE MATERIALS BY FUNDAMENTAL STRENGTH PROPERTIES, WHICH CAN BE USED TO SHOW CHANGES IN THE MECHANICAL PROPERTIES OF THE MATERIAL CAUSED BY THE TYPE OR AMOUNT OF COMPACTIVE ENERGY APPLIED. THIS PHASE OF THE STUDY WAS CONCERNED WITH CONVENTIONAL AND RHEOLOGICAL STRENGTH AND DEFORMATION PROPERTIES OF SOILS IN ORDER TO SUPPLY HIGHWAY TECHNOLOGISTS WITH IMPROVED TECHNIQUES TO EVALUATE SOIL COMPACTION. ONE METHOD ADVANCED FOR EVALUATING SOIL COMPACTION IS BASED ON THE CONFINED AND THE UNCONFINED CONSTANT-LOAD CREEP TESTS, THE STRESS-RELAXATION EXPERIMENTS, AND THE REPEATED LOADING RESEARCH PROGRAM USING A SINGLE RHEOLOGICAL SOIL STRENGTH PARAMETER. THE SOIL STRENGTH PARAMETER UTILIZED, AS FAR AS THIS STUDY IS CONCERNED, IS ANALOGOUS TO THE CONCEPT OF ELECTRICAL IMPEDANCE. THIS STUDY HAS UTILIZED THE ELECTRICAL -MECHANICAL ANALOGY AND THE COMPLEX ELEASTIC MODULUS TO DEFINE THE MECHANICAL RESPONSE OF SOILS. THE INVESTIGATION HAS SHOWN THAT THE STRENGTH PARAMETER USED IS INDEPENDENT OF THE TYPE OF TEST PERFORMED AND HENCE ONLY ONE TEST SUCH AS AN UNCONFINED CREEP TEST CAN BE EMPLOYED TO DEFINE SOIL COMPACTION BY RHEOLOGICAL MODULI. RHEOLOGICAL TESTS TO STUDY THE MECHANICAL RESPONSE OF SOILS PREPARED BY SEVERAL DIFFERENT TYPES OF COMPACTION METHODS WERE CARRIED OUT ON THE PHENOMENOLOGICAL LEVEL. ANALYSES OF THE DATA TO DETERMINE THE OPTIMUM MATERIAL SCIENCE PARAMETERS TO SPECIFY SOIL COMPACTION WERE COMPLETED, COGNIZANT OF THE FACT THAT THE PARAMETERS MUST BE EASILY AND QUICKLY EVALUATED IN THE LABORATORY AND FIELD CONDITIONS. EXPERIMENTS WERE PERFORMED TO VALIDATE THE APPLICATION OF THE LINEAR VISCOELASTIC THEORY AND MECHANISTIC MODELS TO SOILS AND TO DETERMINE THE LIMITATIONS OF SUCH APPROACHES TO COMPACTION PROBLEMS. VARIOUS TYPES AND AMOUNTS OF COMPACTION ENERGY HAVE BEEN PROGRAMMED FOR THE FOUR SELECTED SOILS. EXPERIMENTS WERE CONDUCTED USING UNSATURATED SOILS OVER A RANGE OF MOLDING WATER CONTENTS, INPUT OF COMPACTION ENERGIES, SATURATIONS, DRY DENSITIES, STRESS-STRAIN LEVELS, AND OTHER ENVIRONMENTAL CONDITIONS. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:40:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/121825</guid>
    </item>
    <item>
      <title>NON-NEWTONIAN BEHAVIOR OF ASPHALT CEMENTS</title>
      <link>https://trid.trb.org/View/100106</link>
      <description><![CDATA[THE NON-NEWTONIAN BEHAVIOR OF ASPHALT CEMENTS IS STUDIED BY APPLICATION OF MICRORHEOLOGICAL AND REACTION KINETIC PRINCIPLES. THIS INVESTIGATION INCLUDES BOTH THEORETICAL AND EXPERIMENTAL EVALUATION OF ANOMALOUS FLOW CHARACTERISTICS OF ASPHALTS THROUGH MEASUREMENTS OF VISCOSITY, COMPLEX FLOW, AND THIXOTROPY. THE THEORIES RELATED TO THE EFFECT OF INTERNAL STRUCTURE ON THE NON-NEWTONIAN BEHAVIOR OF ASPHALTS IS REVIEWED AND THE SHEAR DEPENDENCE OF VISCOSITY IS DISCUSSED. THE EFFECT OF THE FLOW OF MACROMOLECULAR UNITS AS DISTINGUISHED FROM THE FLOW OF A SINGLE MOLECULE ON THE OBSERVED NON-NEWTONIAN BEHAVIOR IS EMPHASIZED. IT IS INDICATED THAT THE DEGRADATION OF THESE FLOW UNITS IS THE CONTROLLING FACTOR IN THE ANOMALOUS FLOW CHARACTERISTICS. THE THEORETICAL ANALYSIS OF THE STRUCTURAL CHANGES OCCURRING IN THE MATERIAL AS A RESULT OF APPLICATION OF SHEAR STRESS IS PRESENTED. THE NEWTONIAN AND NON-NEWTONIAN BEHAVIORS WHICH ARE RELATED TO THESE STRUCTURAL CHANGES ARE STUDIED BY APPLICATION OF A REACTION KINETIC PRINCIPLE. THE UTILIZATION OF THIS PRINCIPLE YIELDS AN EQUILIBRIUM CONSTANT FOR THE REACTION BETWEEN THE BROKEN AND UNBROKEN PORTIONS OF THE INTERNAL STRUCTURE. TO CONIRM THE ABOVE THEORIES, EXPERIMENTS WERE CONDUCTED ON VARIOUS TYPES OF ASPHALT CEMENTS BY UTILIZATION OF A SLIDING PLATE MICROVISCOMETER. THE RHEOLOGICAL DATA WERE COLLECTED AT VARIOUS TEMPERATURES RANGING FROM 60 DEGREES F. TO 122 DEGREES F. /AUTHOR/]]></description>
      <pubDate>Mon, 01 Sep 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/100106</guid>
    </item>
    <item>
      <title>RELATIONSHIP BETWEEN THE RHEOLOGICAL PROPERTIES OF ASPHALT AND THE RHEOLOGICAL PROPERTIES OF MIXTURES AND PAVEMENTS. ASPHALT RHEOLOGY: RELATIONSHIP TO MIXTURE. A SYMPOSIUM SPONSORED BY ASTM COMMITTEE D-4 ON ROAD AND PAVING MATERIALS, NASHVILLE, TENNESSEE, 11 DECEMBER 1985. ASTM SPECIAL TECHNICAL PUBLICATION 941</title>
      <link>https://trid.trb.org/View/282561</link>
      <description><![CDATA[The central tenet of this paper is that a proper level of bearing capacity is essential to good asphalt pavement performance.  Methods for designing pavements with increased bearing capacity and methods for measuring this property are recommended.  Since the bearing capacity of asphalt pavements is seldom determined, the fact is often overlooked that many pavement failures that are attributed to stripping, inferior asphalt quality, and inferior stone quality are actually structural failures due to inadequate bearing capacity.  Increased truck tire pressures menace many pavements which were designed to traditional standards but which have bearing capacities too low to cope with the higher stress.  The only practical way to save these pavements from premature failure is to lower the stresses or tire pressure on them during hot weather.  The complexity of the rheology of asphalt and asphalt pavements and the poor precision of test methods used to measure these properties require that the conditions of test be carefully matched to road conditions in order that the results be meaningful. The use of aggregate graded to a high volume concentration and with a top size two-thirds the thickness of the pavement dramatically increases bearing capacity.  Low-viscosity asphalt and air voids of less than 3% greatly increase the durability of asphalt pavements.]]></description>
      <pubDate>Fri, 30 Jun 2000 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/282561</guid>
    </item>
    <item>
      <title>COMPUTATION FOR RHEOLOGICAL PHENOMENA OF ELASTIC-VISCOPLASTIC BODY</title>
      <link>https://trid.trb.org/View/542914</link>
      <description><![CDATA[A computational method is proposed for simulating rheological phenomena of a body composed of a material such as soft soil, powder, and granular material under large excitations.  These phenomena are considered to be elastic-viscoplastic (E-VP) flows with moving boundaries.  Fundamental equations for the dynamics are constructed from the Eulerian viewpoint.  The constitutive laws for pressure volume and deviatoric stress stain are E-VP and are expressed by differential equations.  The pressure and deviatoric stress are combined to satisfy yield conditions.  The equations construct the first-order partial differential equation system.  A domain containing an E-VP body is divided into cells by applying a finite difference method to the partial differential equation system.  The locations of markers distributed in the body are calculated to trace the moving free boundaries.  The collapse of an E-VP square body is shown as an application example.]]></description>
      <pubDate>Wed, 06 Jan 1999 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/542914</guid>
    </item>
    <item>
      <title>TIME-TEMPERATURE DEPENDENCY OF ASPHALT BINDERS -- AN IMPROVED MODEL (WITH DISCUSSION)</title>
      <link>https://trid.trb.org/View/487712</link>
      <description><![CDATA[Asphalt binders exhibit three regions of behavior: non-equilibrium behavior at temperatures below the glass transition temperature, thermal rheologically simple linear viscoelastic behavior in the temperature range between the glass transition temperature (Tg) and Tg + 100 degrees C, and Newtonian behavior at elevated temperatures, typically at temperatures greater than Tg + 100 degrees C. In this paper a recommended procedure for characterizing the rheological behavior in each of these regions is presented. The testing protocol, the statistical procedures used in shifting the data, and the accommodation of the three regions of behavior are considered. Physical hardening is accommodated by an additional parameter in the WLF equation.]]></description>
      <pubDate>Mon, 13 Jul 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/487712</guid>
    </item>
    <item>
      <title>INTERPRETATION OF DYNAMIC MECHANICAL TEST DATA FOR PAVING GRADE ASPHALT CEMENTS (WITH DISCUSSION)</title>
      <link>https://trid.trb.org/View/486935</link>
      <description><![CDATA[Dynamic mechanical analysis, and other methods of rheological testing, have been used for many years on asphalt cement. Unfortunately, there currently exists some confusion over the interpretation of dynamic mechanical data on asphalt cements. In order to clarify appropriate methods of interpreting rheological data on paving grade asphalts, test data for a number of asphalt cements having widely different properties must be analyzed in light of rheological theory and appropriate mathematical models. The purpose of this paper is to describe various useful techniques for interpreting viscoelastic data on asphalt cements. Dynamic mechanical test data is emphasized, although many of the principles presented apply equally well to other types of rheological data.]]></description>
      <pubDate>Fri, 26 Jun 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/486935</guid>
    </item>
    <item>
      <title>THE BENDING BEAM RHEOMETER; A SIMPLE DEVICE FOR MEASURING LOW-TEMPERATURE RHEOLOGY OF ASPHALT BINDERS (WITH DISCUSSION)</title>
      <link>https://trid.trb.org/View/486936</link>
      <description><![CDATA[During the 1970s two devices were introduced to measure low temperature properties of binders: the Schweyer forced capillary rheometer, and the sliding plate rheometer developed by Fenijin and Krooshof and modified by others. The first did not solve the problem because its range is limited to temperatures typically above 0.0 C, while the second suffered from practical problems in the preparation of specimens and analytical problems related to the loading mode under which the specimens were being tested. The bending beam device, introduced at The Pennsylvania State University as part of an FHWA project, solved many of the problems associated with the previous two devices and was used to measure rheological properties at extremely low temperatures with a reasonable degree of precision. As part of the SHRP A-002A project, a new version of the device has been developed and extensive testing has been carried out to improve the testing technique and enhance its repeatability. The new version, which is completely computerized, is being promoted as a specification test device that can give direct, accurate measurements of the creep characteristics of asphalt binders within the low-temperature range. This paper presents the basic ideas around which the device has been developed, describes the main features and capabilities of the new bending beam rheometer, and presents the results of an extensive testing program conducted to evaluate the rheometer.]]></description>
      <pubDate>Fri, 26 Jun 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/486936</guid>
    </item>
    <item>
      <title>CONTROL OF COATING QUALITY BY MECHANICAL RHEOLOGICAL TESTING</title>
      <link>https://trid.trb.org/View/477492</link>
      <description><![CDATA[Bituminous materials have a highly pronounced viscoelastic character. The only way to measure their mechanical properties precisely is to subject them to well-defined loading histories: references to tests at a "constant rate" or with a "constant loading law" are common. A special machine is needed to conduct the tests. It is to meet this need that the Equipment Building Departments of the LPC network have designed and built a servocontrolled machine for rheological testing (MAER). It incorporates the latest technologies; in particular, the servocontrol loop is digital, making it easy to adapt the machine to the materials to be tested. It can also carry out whole series of tests on a single specimen, substantially improving the cost-effectiveness of the machine.]]></description>
      <pubDate>Wed, 29 Apr 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/477492</guid>
    </item>
    <item>
      <title>PREDICTION AND CONTROL OF RUTTING IN ASPHALT PAVEMENTS</title>
      <link>https://trid.trb.org/View/469223</link>
      <description><![CDATA[In this paper a comprehensive research on the deformation behavior of asphalt mixtures is carried out by means of static and dynamic uniaxial creep tests.  Based on the test results an effective rheological model is developed to represent the deformation behavior of asphalt mixtures.  Model parameters of related asphalt mixtures are determined with curve fitting method.  A practical rutting prediction procedure is advanced in terms of both the rheological model and viscoelastic theory. Based on the travel safety analysis of vehicle and the expert consultation the allowable rut depths in asphalt pavements in China are recommended, which are crucial indexes to pavement design and maintenance.  The very significant factors influencing rutting in asphalt pavement are investigated, and several effective rutting control measures are suggested.  A pavement design procedure regarding rutting is developed.]]></description>
      <pubDate>Thu, 27 Nov 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/469223</guid>
    </item>
    <item>
      <title>CHARACTERIZATION OF ASPHALT CEMENTS MODIFIED WITH CRUMB RUBBER FROM DISCARDED TIRES</title>
      <link>https://trid.trb.org/View/577399</link>
      <description><![CDATA[Blends with up to 20% ground vulcanized rubber (both crumb and 200-mesh powder particles) from recycled tires were prepared with asphalt cements of various grades (AC-5 to AC-30) and evaluated using dynamic mechanical analysis (DMA).  Blends produced from powdered rubber particles exhibited Newtonian behavior at high temperatures.  Similar behavior was not observed with crumb rubber blends.  The mechanical properties of asphalt-rubber blends depend on the concentration of rubber additives, the particle sizes, and the chemical composition of the asphalt.  The dynamic mechanical characteristics of all blends are discussed in terms of the stiffness parameter; comparative data are presented according to the Strategic Highway Research Program binder specifications.  Pressure aging vessel (PAV) tests of the asphalt-rubber blends revealed a significant difference between crumb rubber and powdered rubber additives.  Simple blends of crumb rubber with asphalts ranging in grade from AC-5 to AC-30 exhibited phase separation during a thin-film oven aging test.  In contrast, blends with powdered rubber appeared to remain compatible or at least partially compatible through the PAV process, and the blends retained the physical properties associated with the additive.  The DMA data suggest that the low-temperature cracking resistance of asphalt-powdered rubber blends is enhanced.]]></description>
      <pubDate>Wed, 22 Oct 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/577399</guid>
    </item>
    <item>
      <title>MODIFIED ASPHALT PAVEMENT MATERIALS - THE EUROPEAN EXPERIENCE (WITH DISCUSSION)</title>
      <link>https://trid.trb.org/View/575987</link>
      <description><![CDATA[This paper shows that a wide variety of additives and modifiers have been used in conjunction with asphalt in an attempt to improve existing pavement mixtures or to create new paving applications.  A portion of these were selected to illustrate the current trend in technology.  A strong need for effective maintenance processes in the 1960s and 1970s in Europe explains why much of the technology using modifiers and additives has some roots in Europe and has evolved to where it represents a significant portion of the asphalt paving industry.  Today, families of "polymer modified asphalts" have progressively emerged in different countries and appear to have considerable merit.  The information in this paper addresses the nature of polymer modification and several of the applications through various products and processes.  These include chip seals, slurry seals, dense and open hot mix overlays and special mastic and patching systems.  As evidenced from the experience of the European pavement community, several observations and/or conclusions are suggested:  (1) The current growth in polymer modified asphalt appears to represent a trend rather than a fad; (2) Use of polymers and other additives in asphalt has become a practice, having moved beyond the research stage; (3) Modified binders are more versatile in their applications; (4) Modified asphalts are usually considered as quality products; (5) Along with the development of modified asphalt, improved mechanical and rheological tests have been introduced; and (6) Polymers provide considerable improvement in the physical properties of the binder as well as binder-aggregate combinations.]]></description>
      <pubDate>Wed, 06 Aug 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/575987</guid>
    </item>
    <item>
      <title>CHARACTERIZATION METHODOLOGY FOR PREFORMED COMPRESSION SEALS</title>
      <link>https://trid.trb.org/View/576326</link>
      <description><![CDATA[Preformed pavement polychloroprene compression seals were analyzed using dynamic shear rheology and numerical analysis to assess the feasibility of using these techniques to develop an improved methodology for designing and characterizing preformed seals, as well as predicting their field performance.  The investigation consisted of three phases:  (1) dynamic shear rheological analysis of unaged and aged polychloroprene materials to obtain material property input for numerical analysis; (2) numerical analysis of one preformed compression seal web design; and (3) numerical analysis verification through laboratory compression tests of unaged and aged seal materials.  The investigational results indicate advanced material modeling capabilities of finite-element analysis coupled with the material properties obtained through dynamic shear rheological analysis provide a significant capability to explore seal performance variations resulting from different joint seal geometrics, material compositions, and aging characteristics.  The techniques investigated accurately described the deformation of the seal and provided force-displacement relationships, including relaxation with time and stiffening with age.  Additional minor refinements in the techniques developed through this investigation would result in a powerful design and field performance predictive model.]]></description>
      <pubDate>Wed, 06 Aug 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/576326</guid>
    </item>
    <item>
      <title>RHEOLOGICAL PROPERTIES OF RUBBER-MODIFIED ASPHALT</title>
      <link>https://trid.trb.org/View/451517</link>
      <description><![CDATA[Experiments on the shear-flow properties and the creep-rupture behavior of modified asphalt cements were conducted to evaluate the performance of rubber (from used tires) as an asphalt cement modifier.  Results suggest that various asphalt/rubber samples display shear-thickening, Newtonian, and shear-thinning behavior depending on the shear rate.  The addition of rubber increased the shear viscosity, linear viscoelastic functions, elasticity, and creep resistance of the asphalt cement.  These increases suggest that the addition of rubber will improve the low temperature properties of asphalt cement, and that such modifications are essential to reduce the tendency of asphaltic-paving substances to crack in cold climates and to increase the life cycle of the road.]]></description>
      <pubDate>Wed, 25 Oct 1995 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/451517</guid>
    </item>
    <item>
      <title>A CRITICAL REVIEW OF PRESENT KNOWLEDGE OF THE PROBLEM OF RATIONAL THICKNESS DESIGN OF FLEXIBLE PAVEMENTS</title>
      <link>https://trid.trb.org/View/104472</link>
      <description><![CDATA[THE HYPOTHESIS THAT FLEXIBLE PAVEMENTS ARE PERFECTLY ELASTIC APPEARS TO BE VALID FOR LIMITED NUMBERS OF SAFE LEADS OF SHORT DURATION. HOWEVER, FOR SLOW-MOVING OR STATIC LEADS LARGE ENOUGH NEARLY TO OVERSTRESS THE PAVEMENT, A RHEOLOGICAL MODEL IS MORE APPLICABLE. PAVEMENT LAYERS LACKING TENSILE STRENGTH MAY ACCOUNT FOR A LARGE PART OF THE DIFFERENCE BETWEEN CALCULATED AND MEASURED DEFLECTIONS AND STRESSES. THERE MAY BE MERIT IN USING AN EQUIVALENT MODULUS OF ELASTICITY FOR THE SYSTEM. ALTHOUGH POISSONS RATIO HAS LITTLE EFFECT ON CALCULATED STRESSES, A VALUE OF 0.5 SEEMS TO BE APPROPRIATE FOR SOILS AND PAVEMENTS. THE DEFLECTION FACTOR IS IMPORTANT IN RELATION TO THE EFFECT OF PAVEMENT RIGIDITY ON PAVEMENT DEFLECTIONS. THE LAYERED SYSTEM MODEL OF FLEXIBLE PAVEMENTS SHOULD INCLUDE THE CONDITION OF ZERO TENSILE MODULUS OF THE COMPONENT MATERIALS. /RRL/]]></description>
      <pubDate>Mon, 12 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/104472</guid>
    </item>
    <item>
      <title>A NEW APPROACH IN ASPHALT RHEOLOGY</title>
      <link>https://trid.trb.org/View/101159</link>
      <description><![CDATA[ARGUMENTS ARE PRESENTED FOR THE NEED OF USING RHEOLOGY IN SPECIFICATIONS FOR PAVING ASPHALT. THE NEED FOR DETERMINING THE DEFORMATION CHARACTERISTICS EMPLOYING ASPHALT INVARIANT PARAMETERS WITH THE OBJECTIVE THAT SUCH RESULTS WILL BE USEFUL IN BRIDGING THE GAP FROM THE SCIENTIFIC MEASUREMENT OF ASPHALT TO THE UTILIZATION IN THE DESIGN OF BETTER FLEXIBLE PAVEMENTS. A REVIEW OF RECENT PUBLICATIONS PERTINENT TO THE SUBJECT IS INCLUDED AND REFERS IN PARTICULAR TO THE MORE SOPHISTICATED CONSIDERA- TIONS OF RHEOLOGY PHENOMENOLOGICAL BEHAVIOR. FROM THIS BACKGROUND, A NEW METHOD OF CHARACTERIZING THE RHEOLOGY OF ASPHALT IS PROPOSED AS BEING MORE RIGOROUS AND, IT IS HOPED, MORE USEFUL FOR DESIGN PURPOSES. THE PROCEDURE DESCRIBED USES THE INSTRON TESTING MACHINE WITH AN ENVIRONMENT CHAMBER AND A COMPRESSION TEST IN WHICH THE BASIC CONCEPT OF COMPRESSIBILITY IS UTILIZED FOR EVALUATING THREE RHEOLOGICAL PARAMETERS. THESE PARAMETERS ARE THE STRESS-STRAIN RELATION AT A ZERO RATE OF STRAIN CONDITION, A MEASUREMENT OF CONSISTENCY RELATED TO CLASSICAL VISCOSITY, AND A CHARACTERISTIC TIME, WHICH IS A MEASURE OF THE MEMORY OF PREVIOUS STRAINS THAT THE MATERIAL RETAINS AND THAT INFLUENCE ITS RHEOLOGICAL BEHAVIOR. THESE THREE INDEPENDENT MATERIAL PARAMETERS ARE SUFFICIENT TO DESCRIBE THE ASPHALT FOR ALL RHEOLOGICAL PURPOSES. LINE DIAGRAMS ARE PRESENTED TO ILLUSTRATE THE PROCEDURE AND AN EXAMPLE OF THE PROPOSED ANALYSIS FOR AN 85 TO 100 PENETRATION ASPHALT IS GIVEN. /AUTHOR/]]></description>
      <pubDate>Thu, 29 Sep 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101159</guid>
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