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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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>WEIGHT-IN-WATER METHODS OF DETERMINING THE MOISTURE CONTENT OF SOIL-CEMENT MIXTURES IN THE FIELD</title>
      <link>https://trid.trb.org/View/121163</link>
      <description><![CDATA[THE DEVELOPMENTS OF 'WEIGHT-IN-WATER' METHODS OF QUICKLY DETERMINING MOISTURE CONTENTS OF SOIL-CEMENT MIXTURES ARE DESCRIBED AND PROCEDURES OUTLINED FOR USE IN THE FIELD. A DISCUSSION OF THE PAPER BY E.E. BAUER IS PRESENTED POINTING OUT THE IMPORTANCE OF HAVING THE TEMPERATURE OF THE WATER USED IN MAKING BOTH THE SPECIFIC GRAVITY AND MOISTURE TESTS AT RELATIVELY THE SAME VALUE.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:38:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/121163</guid>
    </item>
    <item>
      <title>ENGINEER SOIL MECHANICS TESTS</title>
      <link>https://trid.trb.org/View/119011</link>
      <description><![CDATA[AN ENGINEERING SOIL INVESTIGATION OF AN AREA WAS MADE TO DETERMINE THE PHYSICAL CHARACTERISTICS AND PROPERTIES OF THE FOUNDATION SOIL. A SOIL-BORING PROGRAM WAS UNDERTAKEN FOR THE PURPOSE OF SECURING SAMPLES FOR LABORATORY EXAMINATION AND ANALYSIS. MECHANICAL ANALYSIS OR GRAIN-SIZE DISTRIBUTION, SPECIFIC-GRAVITY DETERMINATIONS, DIRECT SHEAR AND TRIAXIAL COMPRESSION TESTS AND MOISTURE-DENSITY RELATIONSHIPS WERE MADE ON THE RESULTING DISTURBED AND REMOLDED SAMPLES. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:10:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/119011</guid>
    </item>
    <item>
      <title>DENSITY, ABSORPTION AND SPECIFIC GRAVITY TESTS OF AGGREGATES, BITUMINOUS MATERIALS, BITUMINOUS MIXTURES AND SURFACES (ANNOTATED)</title>
      <link>https://trid.trb.org/View/95047</link>
      <description><![CDATA[A REVIEW IS PRESENTED OF AVAILABLE LITERATURE ON DENSITY, ABSORPTION AND SPECIFIC GRAVITY TESTS OF AGGREGATES FOR BITUMINOUS MIXTURES AND OF BITUMINOUS MATERIALS, BITUMINOUS MIXTURES AND SURFACES. THE ANNOTATED BIBLIOGRAPHY IS PRESENTED CHRONOLOGICALLY WITH AN AUTHOR INDEX.]]></description>
      <pubDate>Thu, 29 Jul 2004 17:20:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/95047</guid>
    </item>
    <item>
      <title>LIMESTONE WITH EXCELLENT NON-SKID PROPERTIES</title>
      <link>https://trid.trb.org/View/107084</link>
      <description><![CDATA[THE PROPERTIES OF LIMESTONE WERE INVESTIGATED TO DETERMINE THE FACTORS WHICH CAUSE GOOD SKID RESISTANCE. LIMESTONE IS DEFINED AS SEDIMENTARY ROCK IN WHICH THE CARBONATE FRACTION EXCEEDS THE NONCARBONATE FRACTION AND IN WHICH THE PREDOMINATING METALLIC ELEMENT OF THE CARBONATE IS CALCIUM. FIVE LIMESTONE AGGREGATES, EACH FROM A DIFFERENT SOURCE, WERE SELECTED FOR INCLUSION IN BITUMINOUS CONCRETE MIXES. REALISTIC TEST SECTIONS WERE PLACED IN A CIRCULAR TEST TRACK AND THEIR SKID RESISTANCE MEASURED WITH A SPECIAL DEVICE DESIGNED FOR THIS PURPOSE. THE FIVE BITUMINOUS MIXTURES WERE FOUND TO DIFFER WIDELY IN SKID RESISTANCE. SAMPLES OF EACH OF THE FIVE AGGREGATES WERE LEACHED WITH HYDROCHLORIC ACID AND THE REMAINDERS FILTERED, WASHED, DRIED, AND WEIGHED. THE PERCENTAGES OF CARBONATES AND INSOLUBLE RESIDUE WERE CALCULATED. THIS RESIDUE WAS TESTED FOR GRAIN SIZE DISTRIBUTION BY THE ASTM METHOD AND FOR SPECIFIC GRAVITY. TWO OF THE LIMESTONES TESTED WERE QUITE SLIPPERY. ONE HAD ONLY A SMALL PORTION OF INSOLUBLES WHILE THE OTHER CONTAINED AN APPRECIABLE AMOUNT OF INSOLUBLES. THERE IS EVIDENCE THAT THE SAND SIZED GRAINS OF THE INSOLUBLES IS THE FACTOR THAT IS EFFECTIVE IN PROMOTING SKID RESISTANCE. DATA INDICATE THAT A COMBINATION OF DIFFERENTIAL HARDNESS, AMOUNT OF INSOLUBLE RESIDUE, AND GRAIN SIZE DISTRIBUTION OF THE INSOLUBLE RESIDUE ARE FACTORS THAT DETERMINE THE SKID RESISTANCE OF LIMESTONE AGGREGATES. IT IS KNOWN THAT BLENDS OF LIMESTONE AGGREGATE AND SILICEOUS SAND IN BITUMINOUS MIXTURES CAN PROVIDE SURFACES WITH ADEQUATE SKID RESISTANCE. IT IS ALSO KNOWN THAT SOME CHERTY LIMESTONES (NODULES) HAVE BEEN USED SATISFACTORLY IN SURFACE COURSE MIXTURES HAVING GOOD SKID RESISTANCE. IT IS BELIEVED THAT THE DATA PRESENTED INDICATE THAT A LIMESTONE POSSESSING THE PROPERTIES GIVEN ABOVE COULD BE USED AS THE ENTIRE AGGREGATE IN SURFACE COURSE MIXTURES WHICH WOULD POSSESS ADEQUATE SKID RESISTANCE.]]></description>
      <pubDate>Tue, 01 Jul 2003 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/107084</guid>
    </item>
    <item>
      <title>LABORATORY DEVELOPMENT OF THIRD/FOURTH GENERATION SULPHLEX BINDERS</title>
      <link>https://trid.trb.org/View/472780</link>
      <description><![CDATA[This report presents the findings of a 2-year, multitask study to provide a new generation of Sulphlex binders with enhanced low-temperature fracture resistance.  The initial phases of the program dealt with the preparation and base-line characterization of Sulphlex 233 and 198, First and Second Generation Sulphlex, respectively, considered the more promising of a broad series of formulations developed under earlier Federal Highway Administration programs.  These binders were prepared individually and blended at ratios of 50/50 and 75/25 (198/233) and designated as Third Generation Sulphlex.  The former was prepared by directly blending the two binders as well as by a one-pot synthesis.  These binders were subjected to a series of screening tests including (a) Penetration @ 25 deg C, (b) Viscosity @ 135 deg C, (c) Specific Gravity, (d) Solubility in CHCl3, (e) Storage Stability, and (f) Glass Transition temperature.  A "new and improved" Sulphlex binder designated as Fourth Generation was formulated utilizing the rationale derived from the earlier systems.  Sulphlex mixtures along with a control using an AC-20 asphalt were prepared using a crushed limestone aggregate and tested in accordance with Asphalt Aggregate Mixture Analysis System (AAMAS), American Association of State Highway and Transportation Officials (AASHTO), Strategic Highway Research Program (SHRP or Superpave), and Viscoelastic Systems (VESYS) procedures including (a) Indirect Tension, (b) Diametral Resilient Modulus, (c) IDT Creep, (d) Compressive Creep, (e) Unconfined Compression, (f) Repeated Load Permanent Deformation, and (g) Aging using Resilient Modulus.  A set of generic manufacturing plans and procedures were generated for the production of Sulphlex in sufficient quantity to satisfy the requirements of an hypothetical test road section.]]></description>
      <pubDate>Fri, 27 Feb 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/472780</guid>
    </item>
    <item>
      <title>A STUDY OF CHERT AND SHALE GRAVEL IN CONCRETE</title>
      <link>https://trid.trb.org/View/101796</link>
      <description><![CDATA[CERTAIN CHERT AND SHALE GRAVELS HAVE LONG BEEN RECOGNIZED AS HARMFUL WHEN INCLUDED IN PORTLAND CEMENT CONCRETE EXPOSED TO FREEZING AND THAWING. MANY ORGANIZATIONS HAVE SPECIFICATIONS LIMITING PERCENTAGES OF THESE MATERIALS IN CONCRETE AGGREGATES, BUT FEW OF THESE SPECIFICATIONS DISTINGUISH BETWEEN TYPES OF CHERT AND SHALE FROM DIFFERENT GEOGRAPHICAL AREAS NOR DO THEY ALWAYS TAKE INTO ACCOUNT THE BASIC PHYSICAL PROPERTIES OF THESE MATERIALS. IN THIS STUDY, PORE CHARACTERISTICS, MINERALOGY, TEXTURE, AND STRUCTURE WERE DETERMINED FOR CHERTS AND SHALES FROM NINE INDIANA GLACIAL GRAVEL DEPOSITS BY MEANS OF MICROSCOPIC PETROGRAPHY, X-RAY DIFFRACTION, AND THE COMMON SPECIFIC GRAVITY AND ABSORPTION TECHNIQUES. BLENDS OF 2, 4, 6, AND 10 PERCENT OF CHERT OR SHALE FROM EACH SOURCE WERE MADE WITH A STANDARD DURABLE CRUSHED LIMESTONE COARSE AGGREGATE, AND THESE BLENDS WERE USED IN 3- X 4- X 16-IN. AIR-ENTRAINED CONCRETE BEAMS SUBJECTED TO UP TO 300 CYCLES OF FREEZING AND THAWING. A MEASURE OF THE AMOUNT OF DEEP-SEATED DETERIORATION OF THE BEAMS WAS PROVIDED BY DURABILITY FACTORS CALCULATED FROM THE RESULTS OF NON-DESTRUCTIVE SONIC TESTING OF THE BEAMS AT INTERVALS DURING FREEZE-THAW TESTING. SEVERITY OF SURFACE DETERIORATION WAS ALSO EVALUATED. THE INFLUENCE OF THE BASIC PROPERTIES OF THE CHERT AND SHALE GRAVELS ON THE RESULTS OF THE FREEZE-THAW TESTS WAS THEN DETERMINED. ON THE BASIS OF THE RESULTS OF THESE TESTS, THE EXISTING SPECIFICATIONS ON CHERTS AND SHALES WERE STUDIED TO DETERMINE WHETHER THE SPECIFICATIONS REALISTICALLY CATEGORIZE THESE MATERIALS. DESPITE SIGNIFICANT DIFFERENCES IN THEIR MINERALOGIES, NO DIFFERENCE WAS NOTED IN THE FREEZE-THAW DURABILITIES OF THE VARIOUS CHERT SAMPLES. FOR ALL THE CHERTS, SIGNIFICANT DEEP- SEATED AND SURFACE DETERIORATION OCCURRED ONLY IN BEAMS CONTAINING 6 TO 10 PERCENT OF MATERIAL WITH A BULK SPECIFIC GRAVITY (SATURATED SURFACE-DRY BASIS) OF LESS THAN 2.45. ALTHOUGH THE BASIC PROPERTIES OF THE SHALES VARIED EVEN MORE WIDELY THAN THOSE OF THE CHERTS, NONE OF THE SHALES CAUSED DEEP-SEATED FAILURE OF THE CONCRETE. HOWEVER, THE MOST POROUS SHALES CAUSED POPOUT DAMAGE, WHICH WAS ESPECIALLY SEVERE AT THE 6 AND 10 PERCENT LEVELS. /AUTHOR/]]></description>
      <pubDate>Mon, 12 Sep 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101796</guid>
    </item>
    <item>
      <title>LABORATORY AND FIELD DENSITIES OF HOT-MIX ASPHALTIC CONCRETE IN TEXAS</title>
      <link>https://trid.trb.org/View/101106</link>
      <description><![CDATA[LABORATORY AND FIELD DATA HAVE BEEN COLLECTED FROM TWELVE REGULAR CONTRACT HOT-MIX ASPHALTIC CONCRETE PAVING PROJECTS IN VARIOUS AREAS OF TEXAS FOR THE PURPOSE OF COMPARING LABORATORY AND FIELD DENSITIES. DATA FROM ROAD SAMPLES TAKEN FROM TWO TO NINE MONTHS AFTER THE ROADS WERE BUILT SHOW THAT FIVE OF THE PAVEMENTS EXCEEDED LABORATORY DENSITY BY 1 TO 3 PERCENT AS DETERMINED BY CALCULATION METHODS CURRENTLY USED BY THE TEXAS HIGHWAY DEPARTMENT. NONE OF THE ROAD SAMPLES MEASURED BY THIS METHOD HAD A DENSITY LOWER THAN 97.2 PERCENT (2.8 PERCENT VOIDS). THE AVERAGE DENSITY OF THE TWELVE DIFFERENT SAMPLES WAS 100.0 PERCENT. THE MAXIMUM DENSITY MEASURED 103+ PERCENT. THE SPECIFIC GRAVITIES OF THE MIXES WERE THEN REDETERMINED SO AS TO INCLUDE MOST OF THE ABSORPTION OF ASPHALT CEMENT BY THE AGGREGATE. THESE DATA SHOW AN AVERAGE OF 94.6 PERCENT, WITH A MAXIMUM OF 97.3 PERCENT. THE RANGE OF DIFFERENCES BROUGHT OUT BY THE TWO METHODS WAS FROM 1.9 TO 12.7 PERCENT. DATA ON MIX DESIGN, TRAFFIC AND FIELD CONSTRUCTION ARE INCLUDED FOR BACKGROUND INFORMATION. /AUTHOR/]]></description>
      <pubDate>Sun, 28 Aug 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101106</guid>
    </item>
    <item>
      <title>DELETERIOUS CONSTITUENTS OF INDIANA GRAVELS</title>
      <link>https://trid.trb.org/View/107125</link>
      <description><![CDATA[RESULTS ARE REPORTED OF TESTS ON INDIANA GRAVELS RANGING FROM GOOD TO POOR IN FIELD PERFORMANCE IN PORTLAND-CEMENT CONCRETE. THE GRAVELS WERE SEPARATED BY LIQUID FLOTATION INTO VARIOUS SPECIFIC-GRAVITY RANGES. THE GRAVEL FRACTIONS THUS OBTAINED WERE TESTED TO DETERMINE THE ABSORPTION, SPECIFIC GRAVITY, DEGREE OF SATURATION, LITHOLOGIC COMPOSITION AND DURABILITYIN AIR-ENTRAINED CONCRETE SUBJECTED TO FREEZING AND THAWING. THE RESULTS SHOW THAT THE PRINCIPAL DELETERIOUS CONSTITUENTS OF INDIANA GRAVELS ARE SANDSTONES AND CHERTS. THEY ARE CHARACTERIZED BY LOW SPECIFIC GRAVITY, HIGH ABSORPTION AND DEGREE OF SATURATION, AND PRODUCE NONDURABLE CONCRETE WHEN USED AS THE COARSE AGGREGATE. THE CONCRETE DURABILITY CAN BE IMPROVED BY HEAVY-MEDIA SEPARATION OF THE AGGREGATE. GREATER DURABILITY IS OBTAINED AS THE SPECIFIC GRAVITY AT WHICH THE SEPARATION IS MADE IS INCREASED. /AUTHOR/]]></description>
      <pubDate>Thu, 28 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/107125</guid>
    </item>
    <item>
      <title>PAVEMENT DENSITY-WHAT INFLUENCES IT</title>
      <link>https://trid.trb.org/View/100929</link>
      <description><![CDATA[A RESEARCH PROJECT IS REPORTED WHICH WAS CONDUCTED TO STUDY THE PHYSICAL CHARACTERISTICS OF NEWLY CONSTRUCTED ASPHALT CONCRETE PAVEMENTS. A PORTION OF THE STUDY WAS UNDERTAKEN TO ESTABLISH INHERENT VARIABILITY AND TO DETERMINE THE INFLUENCE OF SUCH VARIABLES AS MIX COMPOSITION, PAVEMENT THICKNESS, MIX TEMPERATURE, AND NUMBER OF ROLLER PASSES ON PAVEMENT DENSITY. FORTY-SEVEN TEST SECTIONS, ONE LANE WIDE AND THE LENGTH OF LAYDOWN OF A TRUCK LOAD WERE STUDIED FROM 12 CONSTRUCTION PROJECTS THROUGHOUT THE STATE. TEMPERATURE MEASUREMENTS WERE MADE OF THE MIXTURE DURING COMPACTION, AND ALL ROLLER PASSES WERE RECORDED. BULK DENSITY, ASPHALT EXTRACTION, AGGREGATE GRADATION AND SPECIFIC GRAVITY TESTS WERE CONDUCTED ON PAVEMENT CORES AND MARSHALL SPECIMENS AS WERE PLASTIC FLOW DETERMINATIONS MADE ON THE MARSHALL SPECIMENS. IT WAS CONCLUDED FROM AN ANALYSIS OF THE DATA AS TO PAVEMENT DENSITY VARIABILITY THAT: (1) DENSITY DOES NOT VARY SIGNIFICANTLY IN THE LONGITUDINAL DIRECTION, (2) INITIAL PAVEMENT DENSITY VARIES SIGNIFICANTLY ACROSS THE LANE, BEING GREATEST IN THE CENTER AND LEAST NEAR THE EDGE, (3) TRAFFIC INCREASES PAVEMENT DENSITY AND DECREASES VARIATION, (4) INITIALLY, 29 PERCENT OF THE PAVEMENT AREAS HAD A DENSITY LESS THAN 95 PERCENT MARSHALL, WHICH AFTER ONE YEAR OF TRAFFIC WAS REDUCED TO 8 PERCENT AND AFTER 2 YEARS TO 4 PERCENT, AND (5) AFTER TWO YEARS' SERVICE, THE PAVEMENTS ARE SMOOTH-RIDING WITH NO OBSERVABLE SURFACE DEFECTS. A SERIES OF REGRESSION ANALYSES PERFORMED BY ELECTRONIC COMPUTER SHOWED THE FOLLOWING FACTORS WHICH AFFECTED VOIDS IN THE FOLLOWING ORDER: (1) ASPHALT CEMENT CONTENT, (2) PAVEMENT REBOUND DEFLECTION, (3) AGGREGATE GRADATION, (4) ASPHALT CEMENT VISCOSITY, (5) INTERMEDIATE ROLLER PASSES, (6) BREAKDOWN ROLLER PASSES, AND (7) FINAL ROLLER PASSES. THE NEW YORK STATE SPECIFICATION CONTROL ON TEMPERATURE AND ROLLING OF HOT-MIX ASPHALT CONCRETE WAS DETERMINED TO BE ADEQUATE TO PRODUCE PAVEMENTS OF PROPER DENSITY FOR GOOD PERFORMANCE.]]></description>
      <pubDate>Tue, 24 May 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/100929</guid>
    </item>
    <item>
      <title>SIGNIFICANCE OF TESTS FOR ASPHALTIC MATERIALS</title>
      <link>https://trid.trb.org/View/97990</link>
      <description><![CDATA[STANDARD ROUTINE TESTS ARE PRESENTED ON SPECIFIC GRAVITY, CONSISTENCY, SOLUBILITY, HEATING, DISTILLATION, DUCTILITY, CURING INDEX TEST AND VACUUM DISTILLATION TEST.]]></description>
      <pubDate>Thu, 21 Apr 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/97990</guid>
    </item>
    <item>
      <title>EVALUATION OF SKID RESISTANCE FOR HIGH-TYPE BITUMINOUS SURFACES. FINAL REPORT</title>
      <link>https://trid.trb.org/View/380825</link>
      <description><![CDATA[Investigations of 13 field test sections indicated that the key to preventing early loss in skid resistance is to ensure that field air-void contents do not fall below 3.4% for ID-2 mixtures and 3.0% for ID-3 mixtures.  The existing mixture design and acceptance procedures employed by PennDOT, as well as existing field control and acceptance procedures, were determined to be primary contributors to the design and acceptance of mixtures that are likely to have low air-void contents and associated problems with early loss in skid resistance.  A new procedure was developed and recommended to determine optimum asphalt content and to screen mixture designs that are particularly sensitive to changes in asphalt content.  The modified Texas gyratory compactor, using the new SHRP protocol, was found to do a better job than Marshall compaction in the production of laboratory mixtures that are more representative of the field. However, additional studies were recommended to identify and validate the best laboratory compaction method.  It was also determined that stricter acceptance criteria should be established on the air-void content of laboratory-compacted, plant-produced mixtures.  Additional field controls were recommended to ensure that accurate estimates of maximum specific gravity are obtained during production to allow for better control of air voids.]]></description>
      <pubDate>Wed, 01 Dec 1993 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/380825</guid>
    </item>
    <item>
      <title>FREEZE-THAW EVALUATION OF SELECTED ROCK TYPES FROM A COMPOSITE SAMPLE OF MICHIGAN GRAVEL</title>
      <link>https://trid.trb.org/View/344414</link>
      <description><![CDATA[The glacial gravels of Michigan contain a mixture of durable and non-durable rock types.  The Michigan Department of Transportation (MDOT) classification that defines the gravel constituents (friable sandstone, siltstone, shale, clay ironstone and chert) as deleterious rock types is based upon primarily visual evidence of distress in concrete, such as exposure in pop-outs.  Laboratory test documentation to support the classification has been lacking.  24 rock types sorted from glacial gravel obtained from 49 selected sources were subjected to the standard MDOT laboratory acceptance tests for aggregates, including those for freeze-thaw durability, abrasion loss, and sulfate soundness loss. Additional information was obtained from specific gravity, absorption, and Iowa Pore Index determinations.  Results of the laboratory tests supported the MDOT classification.  The deleterious rock types showed low freeze-thaw durability in concrete; the durable rock types showed high durability. The durable rock types exhibited no ill effects from vacuum saturation pre-treatment for freeze-thaw testing.  Most of the deleterious rock types displayed undesirable pore characteristics similar to the D-cracking carbonates investigated in Iowa.  The deleterious rock types also recorded lower specific gravities and higher absorptions than the durable rock types indicating that heavy media separation can remove most of the deleterious rock types from Michigan glacial gravels.  The carbonate rock constituents including possible D-cracking particles were not evaluated, but will be investigated in a separate study.]]></description>
      <pubDate>Fri, 30 Nov 1990 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/344414</guid>
    </item>
    <item>
      <title>EVALUATION OF THE SUPPLEMENTAL PROCEDURE OF THE MAXIMUM SPECIFIC GRAVITY TEST FOR BITUMINOUS PAVING MIXTURES. FINAL REPORT</title>
      <link>https://trid.trb.org/View/344009</link>
      <description><![CDATA[The objective of this study was to investigate the effects of performing the supplemental procedure of AASHTO T 209 (or ASTM D 2041) on the percent air voids, the effective aggregate specific gravity, and the maximum specific gravity of a bituminous paving mixture, using both thoroughly coated aggregates and partially coated aggregates.  The supplemental procedure should correct the test data for water absorbed into the aggregate during the test.  Although the supplemental procedure can be used when designing mixtures, it is most often used for determining the maximum specific gravities of moisture damaged pavement samples, or cores or specimens where sawing has exposed a significant amount of aggregate.  The majority of aggregates used in this study had water absorptions below 2.5% and thus were not highly absorptive.  It is recommended that the supplemental procedure not be peformed on laboratory mixtures or pavement cores having aggregates with water absorptions below 2.5%.  When testing any mixture prepared in the laboratory during the mixture design process, the procedure for determining the maximum specific gravity should only be performed on well coated mixtures so that the supplemental procedure does not have to be used.  For highly absorptive aggregates, it is recommended that the test only be performed at high binder contents which provide thick coatings.  Only binder contents close to or slightly above the optimal binder content should be used.  The maximum specific gravities for the lower binder contents can be calculated using the effective specific gravity of the aggregate.  For laboratory mixtures containing highly absorptive aggregates, the supplemental procedure may indicate whether the coating is sufficient.]]></description>
      <pubDate>Wed, 31 Oct 1990 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/344009</guid>
    </item>
    <item>
      <title>EVALUATION OF ALTERNATIVE METHODS TO OBTAIN SPECIFIC GRAVITY OF COARSE AGGREGATE. FINAL REPORT</title>
      <link>https://trid.trb.org/View/344184</link>
      <description><![CDATA[AASHTO has a standard test method for determining the specific gravity of aggregates.  The people in the Aggregate Section of the Central Materials Laboratory perform the AASHTO T-85 test for AMRL inspections and reference samples. Iowa's test method 201B, for specific gravity determinations, requires more time and more care to perform than the AASHTO procedure.  The major difference between the two procedures is that T-85 requires the sample to be weighed in water and 201B requires the 2 quart pycnometer jar.  Efficiency in the Central Laboratory would be increased if the AASHTO procedure for coarse aggregate specific gravity determinations was adopted.  The questions to be answered were:  (1) Do the two procedures yield the same test results?  (2) Do the two procedures yield the same precision?  An experiment was conducted to study the different test methods.  From the experimental results, specific gravity determinations by AASHTO T-85 method were found to correlate to those obtained by the Iowa 201B method with an R-squared value of 0.99.  The absorption values correlated with an R-squared value of 0.98.  The single operator precision was equivalent for the two methods. Hence, this procedure was recommended to be adopted in the Central Laboratory.]]></description>
      <pubDate>Wed, 31 Oct 1990 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/344184</guid>
    </item>
    <item>
      <title>MAXIMIUM THEORETICAL SPECIFIC GRAVITY OF BITUMINOUS PAVING MIXTURES</title>
      <link>https://trid.trb.org/View/275237</link>
      <description><![CDATA[To calculate the percentage of voids in a bituminous pavement mixture, it is necessary to determine the maximum theoretical specific gravity of the mixture. Test procedures being used to determine the maximum theoretical specific gravity of bituminous mixtures made with absorptive aggregates have proved to be troublesome.  The specified procedure has also been found to be questionable when used for recycled asphalt pavement testing.  This report discusses and compares test results and void calculations when different test procedures are used to determine the maximum theoretical specific gravity of absorptive aggregates in bituminous mixtures.]]></description>
      <pubDate>Mon, 29 Feb 1988 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/275237</guid>
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