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    <title>Transport Research International Documentation (TRID)</title>
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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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      <link>https://trid.trb.org/</link>
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    <item>
      <title>COMPARISON OF AGGREGATE GRADINGS FOR HIGHWAYS BASED ON THEIR VOIDS CHARACTERISTICS</title>
      <link>https://trid.trb.org/View/269935</link>
      <description><![CDATA[The grading of aggregates for road construction can differ widely from one agency to the next.  In an effort to identify a specific parameter for the design of gradings, the packing and voids characteristics of aggregates of different sizes were studied.  It was observed that the voids structure in an aggregate mixture depends on the size ratios and volumetric proportions of the aggregates contained in the mixture.  The voids structure was defined as "composite" or "filler" type depending on the size ratios of the components.  The components were further subdivided into "balanced", "abundant in fine aggregate" and "abundant in coarse aggregate".  It was found that aggregate grading can be analysed for its voids structure if the size ratios and proportions of consecutive aggregate size fractions are known.  An experimental investigation was carried out to compare three standard specified gradings with skip gradings possessing the same voids ratios as standard grading, but with their components proportioned at or near the balanced stage.  The Marshall characteristics of such skip-graded mixtures were observed to be superior to those of the standard continuously-graded mixtures.  This shows that the strength characteristics of a pavement mixture are influenced by the voids structure as well as the voids volume.  Aggregate grading can therefore be designed by selecting the sizes of aggregate groups so as not to lose the composite structure and by selecting them in balanced proportions.  For the covering abstract see TRIS 450963. (TRRL)]]></description>
      <pubDate>Fri, 27 Aug 2004 21:57:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/269935</guid>
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      <title>AN INVESTIGATION OF THE STABILITY OF UNBOUND BASECOURSE PAVEMENTS</title>
      <link>https://trid.trb.org/View/139427</link>
      <description><![CDATA[This paper reviews one of the first projects initiated by the Pavements Sub-Committee of the Road Research Unit.  The investigation was designed to compare the aggregate characteristics of unbound base course pavements in sound and failing conditions in order to determine parameters controlling stability.  To explain the condition of each of the pavements tested, a theory was suggested linking the aggregate grading and density at end of construction with the possibility of deterioration of the pavement.  It was concluded that base courses with dense gradings were most likely to be stable while those with coarse grading coupled with a potential for high plasticity could experience shear failure.  The unbound base course pavements considered in this project comprised a close packed arrangement of angular shaped rock.  It has been suggested, on the basis of information obtianed from this project, that where the particle size distribution of the aggregate as constructed, was on the coarse side of an optimum grading that inter-particle movement could take place.  Such movement was considered to result in abrasion of the particles causing a change in the grading and in some cases the release of plastic fines and an increase in the base course density.  Densification was considered to be a function of traffic loading.  The development of ruts in a pavement could result in rupture of the surface seal, allowing water to enter.  The effect of moisture intrusion would depend on the permeability of the aggregate, which is also a function of grading.  An open graded aggregate would allow the intrusion of water.  Excess moisture combined with high plasticity could lead to shear failure.  Pore water pressure effects could also contribute in such circumstances.  Dense graded aggregates on the other hand compacted to maximum density would not be expected to suffer mechanical degradation nor densification.  Water intrusion would not be expected because of the lack of surface rutting and relatively low permeability of the base course.  Inclusion of cohesive plastic fines in the aggregate would appear to be an advantage in this case because of its effect in decreasing the permeability and adding cohesion.  Deformation of the subgrade under load could also have an influence on inter-particle movement. No information on pavement deflection was obtained in this project.  An extension of the brief to cover this aspect is being considered. /AUTHOR/]]></description>
      <pubDate>Mon, 16 Aug 2004 20:42:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/139427</guid>
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    <item>
      <title>SOIL AGGREGATE MIXTURES FOR HIGHWAY PAVEMENTS</title>
      <link>https://trid.trb.org/View/119389</link>
      <description><![CDATA[THIS STUDY INCLUDED A REVIEW OF THE AVAILABLE LITERATURE IN THE FIELD OF SOIL-AGGREGATE CONSTRUCTION. A COMPREHENSIVE ANNOTATED BIBLIOGRAPHY WAS PUBLISHED IN THREE PARTS. BASED ON INFORMATION OBTAINED IN PARTS ONE AND TWO OF THE BIBLIOGRAPHY, A COMPREHENSIVE REPORT, MANUAL OF CURRENT PRACTICE FOR THE DESIGN, CONSTRUCTION AND MAINTENANCE OF SOIL-AGGREGATE ROADS WAS PUBLISHED IN 1959. THE INFORMATION DEVELOPED LATER IN THIS STUDY WAS NOT SUFFICIENT TO REVISE THIS REPORT TO A MANUAL OF RECOMMENDED PRACTICE OR TO REVISE THE PRESENT SPECIFICATIONS FOR SOIL-AGGREGATE MIXTURES. THE LATER LABORATORY RESEARCH IS CONCERNED WITH THE EFFECTS OF /1/ AGGREGATE CHARACTERISTICS, /2/ AGGREGATE GRADATION, AND /3/ PLASTICITY INDEX ON THE DENSITY AND SHEAR STRENGTH OF SOIL AGGREGATE MIXTURES. THIS RESEARCH SHOWS THOSE AREAS OF THE PRESENT SPECIFICATION WHICH GIVE BEST RESULTS. THE LATER FIELD RESEARCH IS CONCERNED WITH THE CORRELATION OF IN-SITU SHEAR STRENGTH /BURGGRAF SHEAR APPARATUS/ WITH FIELD MOISTURE CONTENT, FIELD DRY DENSITY AND OTHER PROPERTIES. /BPR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:19:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/119389</guid>
    </item>
    <item>
      <title>HIGH-STRENGTH LIGHTWEIGHT CONCRETE MADE OF POROUS AGGREGATES FROM INDUSTRIAL WASTE</title>
      <link>https://trid.trb.org/View/100434</link>
      <description><![CDATA[AGLOPORITE, WHICH IS MANUFACTURED BY THE CONTACT SINTERING OF CLAY MATERIALS AND INDUSTRIAL WASTES ON SINTERING MACHINES, IS USED AS A LIGHTWEIGHT AGGREGATE FOR CONCRETE MIXES. AGLOPORITE HAS A RELATIVELY SIMPLE PRODUCTION FLOWSHEET AND IS ONE OF THE MOST EFFICIENT TYPES OF POROUS AGGREGATES. THE PRINCIPAL STARTING MATERIAL IS ZAGLIK ALUNITE. DURING PROCESSING, THE ORE YIELDS 50 PERCENT WASTE IN THE FORM OF SAND AND MUD FRACTIONS CONTAINING ABOUT 80 PERCENT SILICON OXIDE. A TRIAL BATCH OF AGLOPORITE POROUS AGGREGATES WAS OBTAINED AND A RESEARCH PROGRAM ON ITS MANUFACTURE WAS STARTED. THE PROPERTIES OF AGLOPORITE WERE STUDIED AND THE RESULTS ARE TABULATED. AGLOPORITE WAS USED IN THE MANUFACTURE OF STRUCTURAL LIGHTWEIGHT CONCRETES OF STRENGTH EQUAL TO OR GREATER THAN 400 KG PER SQUARE CENTIMETER. FOR CONCRETES OF BRAND 300 AND 400, CONSUMPTION OF BRAND-400 CEMENT DOES NOT EXCEED 400 AND 500 KG PER CUBIC METER OF CONCRETE MIX, RESPECTIVELY. FOR CONSTRUCTIONAL AGLOPORITE CONCRETE, THE DESIGNERS SUGGEST THE FOLLOWING PARTICLE-SIZE DISTRIBUTION AGGREGATE: SAND, 33-35 PERCENT; CRUSHED MATERIALS OF SIZE 50-10 MM, FROM 20 TO 25 PERCENT BY VOLUME; CRUSHED MATERIALS OF SIZE 10-20 MM, FROM 35 TO 40 PERCENT BY VOLUME. THE SPECIFIC WEIGHT OF THE CONCRETE AND THE SELECTION OF THE COMPOSITION FOR THE MIX OF HIGH STRENGTH AGLOPORITE CONCRETE IS DISCUSSED. RECENT STUDIES INDICATE THE POSSIBIL- ITY OF FURTHER REDUCING THE BULK WEIGHT OF AGGREGATE WITHOUT REDUCING ITS STRENGTH.]]></description>
      <pubDate>Thu, 11 Dec 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/100434</guid>
    </item>
    <item>
      <title>AGGREGATE PROPERTIES RELATED TO PAVEMENT PERFORMANCE (WITH DISCUSSION)</title>
      <link>https://trid.trb.org/View/486927</link>
      <description><![CDATA[Aggregate is produced from one of three sources: sand and gravel deposits, stone quarries, or synthetic. The sand and gravel most often comes from stream deposits, but may also be from glacial or alluvial fans. The quarried material comes from bedrock deposits. These are classified as igneous, metamorphic, or sedimentary. Synthetic aggregate is made from materials that have undergone a chemical synthesis that permanently changes the original components. Shale when heated will pop like popcorn. The resulting lightweight material makes an excellent, but expensive skid-resistant aggregate. Since synthetic aggregates are unique, they will not be further discussed. The rest of the paper discusses natural aggregates, their production and how their properties affect pavement performance.]]></description>
      <pubDate>Wed, 25 Jun 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/486927</guid>
    </item>
    <item>
      <title>IMPORTANCE OF ASPHALT-AGGREGATE INTERACTIONS IN ADHESION (WITH DISCUSSION)</title>
      <link>https://trid.trb.org/View/486836</link>
      <description><![CDATA[Asphalt-aggregate interactions are important for the adhesion of asphalt to aggregate and for the maintenance of that bond upon the intrusion of water. Research has been performed in SHRP A-003A at Oregon State University and in SHRP A-003B at Auburn University to examine the physicochemical phenomena occurring at the asphalt-aggregate interface and how the asphalt in the interstices of the aggregate affects bonding. The effect of these phenomena on the behavior of the mixture has been evaluated. In particular, the effect of water on the chemical interaction between asphalt and aggregate and on the longevity of the adhesive bond has been addressed. Through this research, these projects are developing tests that predict the resistivity of particular asphalt-aggregate pairs to water and describe and predict mix performance under wet and dry conditions.]]></description>
      <pubDate>Wed, 05 Jun 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/486836</guid>
    </item>
    <item>
      <title>QUALITY REQUIREMENTS FOR AGGREGATES. A LITERATURE SURVEY</title>
      <link>https://trid.trb.org/View/46152</link>
      <description><![CDATA[The Swedish cement and concrete research institute and the national Swedish road and traffic research institute made A joint attempt to carry out a survey of the literature with A view to investigating the effects of certain properties of aggregates. This survey deals with petrographic composition specific gravity, grading, particle shape, strength, bond to binders, durability (resistance to weathering) resistance to polishing (in road pavements), moisture content, thermal properties, percentage of organic impurities, degree of freedom from coatings of clay and the like, chloride content, and capacity for protection against radiation. /TRRL/]]></description>
      <pubDate>Sat, 13 Apr 2002 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/46152</guid>
    </item>
    <item>
      <title>ROLE OF CHEMICAL AND MINERAL ADMIXTURES ON PHYSICAL PROPERTIES AND FROST-RESISTANCE OF RECYCLED AGGREGATE CONCRETE</title>
      <link>https://trid.trb.org/View/542151</link>
      <description><![CDATA[Recycling demolished concrete as an alternative source of coarse aggregates for the production of new concrete can help solve the growing waste disposal crisis and the problem of depleted natural aggregates.  However, to make such recycling feasible, the strength and durability of the recycled aggregate concrete (RAC) must be assured.  Even though much is known about the mechanical properties of recycled aggregate concrete, an important question remains about its freeze-thaw durability, and it appears that widespread utilization of such concrete will be limited until this question is addressed.  This study was an attempt to investigate and compare how the frost resistance of the RAC and natural aggregate concrete (NAC) is affected by using mineral and chemical admixtures in their production.  From the strength point of view, the recycled aggregate compared well with the natural aggregate in all cases, and therefore, could be considered for various potential applications.  From the frost resistance point of view, the recycled aggregate had negative effects on durability performance.  However, with the use of chemical admixtures, particularly air entrainment, the RAC was found to be as durable as the NAC.]]></description>
      <pubDate>Sun, 27 Dec 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/542151</guid>
    </item>
    <item>
      <title>IMAGE ANALYSIS EVALUATION OF AGGREGATES FOR ASPHALT CONCRETE MIXTURES</title>
      <link>https://trid.trb.org/View/540311</link>
      <description><![CDATA[The performance of asphalt concrete mixtures is influenced by the properties of the included aggregates, such as grading, shape (angularity and elongation), and texture (roughness). Complete and accurate quantification of aggregate properties is essential for understanding their influence on asphalt concrete and for selecting aggregates to produce high-quality paving mixtures.  Recent developments in the use of digital image analysis techniques for quantifying aggregate morphological characteristics in asphalt concrete are summarized.  Image morphological characteristics were used to quantify flatness and elongation of coarse aggregates, to estimate the proportion of natural sand in fine aggregates, and to correlate aggregate characteristics with engineering properties of asphalt concrete mixtures.  Image analysis of sections also revealed information about the grading, shape, and orientation of coarse aggregates in a mixture.  An overview is presented of the broad range of useful pavement engineering applications of this relatively new approach for evaluating aggregate characteristics.]]></description>
      <pubDate>Fri, 30 Oct 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/540311</guid>
    </item>
    <item>
      <title>MUNICIPAL SOLID WASTE BOTTOM ASH AS PORTLAND CEMENT CONCRETE INGREDIENT</title>
      <link>https://trid.trb.org/View/635872</link>
      <description><![CDATA[The disposal of municipal solid waste ash has become a significant economic and environmental issue.  Municipal solid waste ash can be considered to have a fly ash and a bottom ash component.  Municipal solid waste bottom ash (MSWBA) from a refuse-derived fuel facility was evaluated as a potential portland cement concrete ingredient.  Portland cement-related ASTM methods and other analytical techniques such as x-ray diffraction were used.  The sample MSWBA was found to be a marginal concrete aggregate.  The sample MSWBA met most ASTM C 331 standards such as size gradation, but the high angularity and brittle nature of the MSWBA would significantly affect concrete workability.  The MSWBA sulfate and chloride concentrations also were high enough to create potential sulfate attack and reinforcing steel corrosion problems.  Iron removal and aggregate processes such as size control offer cost-effective methods to improve MSWBA for use as an aggregate.]]></description>
      <pubDate>Thu, 17 Sep 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/635872</guid>
    </item>
    <item>
      <title>T283 TEST BEING TAILORED TO SUPERPAVE</title>
      <link>https://trid.trb.org/View/635829</link>
      <description><![CDATA[The American Association of State Highway and Transportation Officials (AASHTO) T283 (Resistance of Compacted Bituminous Mixtures to Moisture Induced Damage) is the test procedure most highway agencies use when determining if asphalt pavements are susceptible to moisture-induced damage and thus would benefit from the addition of anti-stripping agents.  T283 is relatively inexpensive to use and can be accurate at identifying moisture-sensitive asphalt mixes.  The low cost and accuracy of the T283 test procedure led Strategic Highway Research Program researchers to select it for use with Superpave mixes.  However, T283 has not been calibrated for use with mix samples produced using the Superpave gyratory compactor.  Fine-tuning T283 for use with Superpave mixes should be reasonably straightforward.  Until new guidelines on the use of T283 with Superpave mix samples are available, however, highway agencies should pay close attention to the characteristics of their aggregates, which are the most common cause of stripping in asphalt pavements.]]></description>
      <pubDate>Sat, 12 Sep 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/635829</guid>
    </item>
    <item>
      <title>THE VDG 40 PARTICLE SIZE ANALYSER: AN INNOVATIVE TOOL FOR IMPROVED COMPETITION</title>
      <link>https://trid.trb.org/View/485302</link>
      <description><![CDATA[The VDG 40 is an innovative tool that will help improve the quality and productivity of aggregate manufacturing.  The VDG 40 analyzes the image of particles falling freely between a CCD camera and a light source.  A processing algorithm based on an ellipsoid of revolution provides the main geometrical characteristics of the analyzed particles.  Applications for the particle size analyzer might be to control any qualitative changes in the finished product or to gather data for the optimization of production controls and minimize the cost of rejects and of downtime in the quarry.]]></description>
      <pubDate>Mon, 03 Aug 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/485302</guid>
    </item>
    <item>
      <title>THE APPLICATION OF THE FOG SEAL TECHNOLOGY ON A MULTIPLE CHIP SEAL IN GHANA</title>
      <link>https://trid.trb.org/View/487721</link>
      <description><![CDATA[In Ghana, many surface-dressed major roads due for rehabilitation are being or have already been resurfaced with asphaltic overlays as part of a major effort to upgrade some of the country's roads. One major problem with surface-dressed roads is whip-off of loose and insufficiently-embedded aggregates when the roads are opened to traffic, leading eventually to insufficient aggregate cover on the pavement surface. To deal with this problem, a proposal for the application of fog seal technology on a trial basis on two roads due for rehabilitation and resurfacing by double surface dressing was accepted for implementation. This paper highlights the construction processes and the initial specifications adopted for the fog seal construction.]]></description>
      <pubDate>Mon, 13 Jul 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/487721</guid>
    </item>
    <item>
      <title>VALIDATION EXPERIMENTS FOR PERMANENT DEFORMATION TESTING OF BITUMINOUS MIXTURES (WITH DISCUSSION)</title>
      <link>https://trid.trb.org/View/487708</link>
      <description><![CDATA[Results from repeated load uniaxial compression and small-scale wheel tracking tests both correctly ranked four different asphalt concrete mixtures with respect to rutting performance in pilot-scale experiments. The mixtures involved a "good" and "poor" aggregate and a standard and an SBR modified binder. It was found to be desirable for the binder stiffness in the compression tests to match that in the pavement because of the significant influence which the binder has on permanent deformation resistance of dense mixtures. Using an internal partial vacuum to apply a confining stress in repeated load compression tests produced appropriate conditions for testing materials which rely strongly on aggregate characteristics to mobilize permanent deformation resistance.]]></description>
      <pubDate>Fri, 10 Jul 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/487708</guid>
    </item>
    <item>
      <title>AN EVALUATION OF THE WATER SENSITIVITY OF ACID RAIN ON MODIFIED ASPHALT CONCRETE IN TAIWAN</title>
      <link>https://trid.trb.org/View/485093</link>
      <description><![CDATA[Stripping is defined as the breaking of the adhesive bond between the aggregate surface and the asphalt cement in the asphalt concrete.  This study found that the best proportions for an asphalt concrete were 1% lime, 3% mineral filler and 5.5% asphalt content.  This mixture was found to be the most efficient in improvement of the stripping resistance of asphalt mixtures.  The use of lime in asphalt cement can reduce the temperature susceptibility and the penetration, increasing the viscosity and softening point of asphalt materials, which will improve the pavement resistance  to rutting, shoving, bleeding, cracking and aging.  The use of an artificial environmental conditioning system effectively simulates the conditions of acid rain on pavements, so it should be worthwhile to develop this system to study the behavior of immersed asphalt mixtures.]]></description>
      <pubDate>Wed, 08 Jul 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/485093</guid>
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