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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <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>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>USE OF NONDESTRUCTIVE TESTING IN THE DESIGN OF OVERLAYS FOR FLEXIBLE PAVEMENTS</title>
      <link>https://trid.trb.org/View/270797</link>
      <description><![CDATA[The results of a recent study conducted for FHWA are described in this paper. The objective of the study was to develop a ready reference that describes available nondestructive testing (NDT) devices and methods for use in designing the thickness of asphalt concrete overlays for flexible pavements. The report was developed to serve as a guide to practicing highway engineers who are considering the purchase of new equipment or developing (or modifying) overlay design procedures for flexible pavements. Selected overlay design procedures that use NDT input are reviewed. Important components related to the use of NDT data with overlay design procedures are discussed. The following items and their relation to overlay design of flexible pavements using deflection data are discussed in depth: seasonal influences on deflections, location of test points on the pavement surface, frequency of testing, need for cores and laboratory testing, type of NDT measurements (i.e., maximum deflection, basin characterization), additional field measurements that are required, corrections to NDT measurements for temperature and so forth, pavement properties calculated or inferred from the NDT measurements, method used to distinguish between different design sections, relationships that are used to convert NDT measurements to design parameters, relationships that relate design parameters to the useful life of the pavement, and the NDT devices that are available for use.]]></description>
      <pubDate>Fri, 27 Aug 2004 21:59:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/270797</guid>
    </item>
    <item>
      <title>COMPUTER SIMULATION OF THE AASHO ROAD TEST</title>
      <link>https://trid.trb.org/View/269587</link>
      <description><![CDATA[The paper describes the verification of a computer program capable of predicting the functional and structural performance of a road as a function of loads, climate and structural design.  The fundamental principle in the computer program is to divide the road into 0.3 metre long sections.  For each section stochastic parameter values are assigned and calculations are carried out week by week for the desired period of time.  Consequently the output as well as the input are stochastic.  In order to test the computer program 180 sections of the AASHT road test were selected for simulation.  These sections covered a large number of different design thicknesses and magnitudes of axle loads. Numerous calculations were carried out, leading to a number of changes to the original submodels. The ultimate results from the simulations proved to be very close to the actual performance measurements.  The effects of a different driving schedule and that of applying Danish climate conditions were studied.  Simulations were also carried out by replacing the accelerated axle application, existing in the AASHT road test, by non-accelerated in service conditions.  This was done both for an AASHT road test climate and for Danish climatic conditions.  Finally sensitivity tests of some of the parameters in the computer program were performed.  For the covering abstract of the proceedings see TRIS 450538.  (TRRL)]]></description>
      <pubDate>Fri, 27 Aug 2004 21:56:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/269587</guid>
    </item>
    <item>
      <title>RESEARCH ON THICKNESS DESIGN FOR SOIL CEMENT PAVEMENTS</title>
      <link>https://trid.trb.org/View/122611</link>
      <description><![CDATA[A PROCEDURE IS PRESENTED FOR THE THICKNESS DESIGN OF SOIL-CEMENT PAVEMENTS. A THEORETICAL EXPRESSION IS DERIVED TO OBTAIN A COMBINED FUNCTION RELATING DEFLECTION AND RADIUS OF CURVATURE. EXPERIMENTAL DATA ARE USED TO MODIFY THE THEORETICAL FUNCTION AND TO OBTAIN AGREEMENT WITH LOAD TEST RESULTS. THE MODIFIED FUNCTION IS COMBINED WITH A LOAD- DEFLECTION RELATIONSHIP FOR SOIL-CEMENT DEVELOPED IN 1965 AND THE FATIGUE PROPERTIES DETERMINED IN 1966, TO FORMULATE A THICKNESS DESIGN PROCEDURE. THE DESIGN EQUATIONS ARE PRESENTED IN THE FORM OF NOMOGRAPHS, AND THE PROCEDURE FOR DETERMINING DESIGN THICKNESS IS ILLUSTRATED BY TWO EXAMPLES. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:44:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/122611</guid>
    </item>
    <item>
      <title>DEVELOPMENT OF APPROPRIATE METHODS FOR EVALUATING THE EFFECTIVENESS OF STABILIZING AGENTS</title>
      <link>https://trid.trb.org/View/122531</link>
      <description><![CDATA[A SUMMARY IS PRESENTED OF A STUDY TO IMPROVE EXISTING METHODS OR DEVELOP NEW METHODS FOR MEASURING THE PERFORMANCE UNDER IN-SERVICE CONDITIONS OF STABILIZED MATERIALS USED IN DESIGN AND CONSTRUCTION OF HIGHWAYS. TYPE I PORTLAND CEMENT WAS SELECTED AS A NONVISCOUS STABILIZING AGENT FOR ONE PART OF THE INVESTIGATION, AND A PENETRATION-GRADE ASPHALT AS A REPRESENTATIVE VISCOUS STABILIZING AGENT FOR THE OTHER PART OF THE STUDY. LABORATORY EXPERIMENTS WERE CONDUCTED ON SEVEN SOILS TO EVALUATE VARIOUS APPROACHES TO THE MEASUREMENT OF THE CHARACTERISTICS OF STABILIZED MATERIALS, FOLLOWED BY A LIMITED AMOUNT OF TEST TRACK STUDY FOR THE PURPOSE OR CORRELATING LABORATORY RESULTS WITH BEHAVIOR OF MODEL PAVEMENTS. THE PROGRAM WAS DESIGNED TO EVALUATE AND DEVELOP TEST PROCEDURES WHICH WILL PRODUCE DEFINITIVE DATA FOR A WIDE RANGE OF MATERIALS HAVING SIMILAR CHARACTERISTICS. FINDINGS FROM THE STUDY ON NONVISCOUS-STABILIZED MATERIALS INDICATE THAT: (1) MINOR VARIATIONS IN THE RELATIVE DENSITY OF THE MATERIALS WILL HAVE A SIGNIFICANT INFLUENCE ON MANY OF THE PHYSICAL PROPERTIES OF THESE MATERIALS, (2) FINE GRAINED SOILS SHOW LARGE VOLUME CHANGE CHARACTERISTICS BOTH WHEN FROZEN AND THAWED IN THE PRESENCE OF FREE WATER AND UNDER VERY LOW HUMIDITY CONDITIONS, (3) SOME MATERIALS LOSE SIGNIFICANT STRENGTH WHEN SUBJECTED TO FREEZE-THAW CYCLES EVEN THOUGH THESE MATERIALS SHOWED LITTLE OR NO LOSS DURING THE STANDARD FREEZE-THAW DURABILITY TEST, AND (4) THE FLEXURAL STRENGTH OF NON-VISCOUS MATERIALS CAN BE ESTIMATED FROM THE COMPRESSIVE STRENGTH TEST, BUT A RELATIVELY LARGE NUMBER OF TESTS ARE NECESSARY TO OBTAIN A REALISTIC ESTIMATE. CREEP STRAIN TEST RESULTS WERE COVERTED FROM THE TIME DOMAIN TO THE FREQUENCY DOMAIN BY THE USE OF FOURIER TRANSFORM. THIS PERMITTED A DETERMINATION OF THE DYNAMIC RESPONSE OF THESE MATERIALS UNDER LOAD FOR THE ENTIRE FREQUENCY RANGE WITH ONLY A SINGLE TEST. MINOR VARIATIONS IN THE TEMPERATURE AT THE TIME OF THE TEST CAUSED SUBSTANTIAL CHANGES IN THE STIFFNESS OF THE MIXTURES.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:43:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/122531</guid>
    </item>
    <item>
      <title>GRANULAR STABILIZED BASE CONSTRUCTION OF ACCESS AND RELOCATION ROADS BY TENNESSEE VALLEY AUTHORITY</title>
      <link>https://trid.trb.org/View/122036</link>
      <description><![CDATA[THE EXPERIENCE OF THE TENNESSEE VALLEY AUTHORITY IN THE CONSTRUCTION OF GRANULAR STABILIZED BASE COARSE IS OUTLINED. THE AUTHORITY HAS CONSTRUCTED APPROXIMATELY 128 MILES OF GRANULAR STABILIZED BASE COURSE, OF WHICH 47.5 MILES HAVE BEEN ACCESS ROADS AND 80.7 MILES RELOCATIONS. CALCIUM CHLORIDE HAS BEEN USED IN THE PROPORTION OF ONE LB. PER SQ. YD. PER 3-IN. COMPACTED LAYER. IT HAS BEEN FOUND EFFECTIVE IN INCREASING COMPACTED DENSITY, HOLDING MOISTURE AND INCREASING BONDS. THE MAINTENANCE COST ON THE COMPLETED SURFACE HAS BEEN EXTREMELY LOW AND HAS AVERAGED LESS THAN $100 PER MILE PER YEAR. THE PERFORMANCE OF THE CRUSHED STONE STABILIZED BASE HAS BEEN CONSIDERABLY BETTER THAN THAT OF THE GRAVEL BASE. STABILIZED GRANULAR BASE COURSES WITH LIGHT BITUMINOUS SURFACES WERE USED TO PROVIDE ACCESS TO 11 DAMS. THE TRAFFIC ON THESE ACCESS ROADS HAS AVERAGED FROM 1,000 TO 1,500 VEHICLES PER DAY FOR PERIODS FROM 2 YEARS TO 5 YEARS. STABILIZED GRANULAR BASE AND LIGHT BITUMINOUS SURFACING HAVE ALSO BEEN USED BY THE AUTHORITY ON BOTH STATE AND COUNTY HIGHWAY RELOCATIONS ON ROADS CONSTRUCTED TO REPLACE EXISTING ROADS THAT WERE FLOODED BY THE VARIOUS RESERVOIRS. THICKNESSES ARE DISCUSSED OF THE STABILIZED BASES. COSTS OF THE STABILIZED BASE CONSTRUCTION ARE DESCRIBED.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:41:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/122036</guid>
    </item>
    <item>
      <title>SUB-BASES - ITALY</title>
      <link>https://trid.trb.org/View/121928</link>
      <description><![CDATA[IT IS KNOWN THAT THE EXECUTION OF STABLE FOUNDATIONS IS AN IMPORTANT ELEMENT FOR THE BEHAVIOR OF SURFACINGS. THIS HAS BEEN CONFIRMED BY THE BEHAVIOR OF SOME CONCRETE CARRIAGEWAYS OBSERVED IN OPEN COUNTRY. WHATEVER THE TYPE OF FOUNDATION IT IS GOOD PRACTICE TO MAKE CERTAIN THAT THE SURFACE LAYERS ARE NOT BOUND TO THE FOUNDATIONS IN ORDER TO AVOID EXPANSIONS AND CONTRACTIONS DUE TO ATMOSPHERIC INFLUENCES BEING CONTRADICTED BY THESE BONDS. IT IS CONSEQUENTLY ADVISABLE TO INTERPOSE BITUMINIZED CARDBOARD SHEETS RESTING ON A THIN LAYER OF SAND BETWEEN THE FOUNDATION AND THE SURFACE LAYERS. THE FOUNDATIONS SHOULD BE CARRIED ON A NON PLASTIC SUB-GRADE WITHOUT A TENDENCY TO BECOME PLASTIC UNDER THE ACTION OF RISING OF WATER OR LATERAL INFILTRATION. FOUNDATIONS ON PLASTIC SOIL HAVE BEEN CORRECTED BY MODIFYING THE GRADING COMPOSITION USING ADEQUATE GRANULAR MATERIALS AND BY CONSTRUCTING A SUB-BASE OR INCREASING THE THICKNESS OF THE FOUNDATION. A SUB-BASE WAS CONSTRUCTED WITH AN APPROPRIATE MIXTURE OF GRAVEL AND SAND, A FOUNDATION IN STABILIZED SOIL BY AN APPROPRIATE GRADING AND ON THE UPPER PART OF THE SUB- BASE AS ON THE FOUNDATION, A SMALL QUANTITY OF BITUMINOUS LIQUID WAS SPREAD TO PLAY THE ROLE OF SURFACE BINDER AND WATERPROOFING AGENT. FOUNDATIONS IN CEMENT STABILIZED SOILS HAVE BEEN CARRIED OUT IN ITALY FOR A FLEXIBLE HIGHWAY BUT THEY HAVE NOT BEEN USED FOR CONCRETE HIGHWAYS.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:41:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/121928</guid>
    </item>
    <item>
      <title>RIGID PAVEMENTS-BELGIUM</title>
      <link>https://trid.trb.org/View/121927</link>
      <description><![CDATA[THE IMPORTANCE OF THE HYGROMETRIC EFFECTS IS EXAMINED, AS WELL AS THE RESISTANCE TO FROST AND REPEATED BENDING FORCES OF LEAN CONCRETE SUB-BASES. A STUDY IS PRESENTED OF: (1) THE STABILIZATION OF SOILS CONTAINING ORGANIC MATTERS, AND (2) THE REACTION OF CEMENT AND THE FINE FRACTION OF SOILS AS A FUNCTION OF THE NATURE OF THE TWO MATERIALS. THE EXCELLENT BEHAVIOR OF REINFORCED CONCRETE SURFACINGS HAS LED TO THE RECENT USE IN: (1) CONTINUOUS SURFACING IN REINFORCED CONCRETE OVER AN OLD CONCRETE CARRIAGEWAY ON A LENGTH OF 3,800 M, AND (2) ON AN OLD BASE IN LEAN CONCRETE - LENGTH 1 KM. THE THICKNESS FOR THESE TWO LENGTHS IS 18 CM, AND THE REINFORCEMENT IS 0.7 PERCENT STEEL TOR AT 42 KG/MILLIMETERS SQUARED ELASTIC LIMIT. MACHINES USED FOR THE MANUFACTURE AND PLACING OF CONCRETE ON HIGHWAYS ARE DESCRIBED. JOINT TECHNIQUES HAVE BEEN IMPROVED BY MECHANICAL FINISH OF JOINTS EXECUTED IN FRESH CONCRETE. A SLIP-FORM PAVER HAS BEEN TRIED. BEHAVIOR OF PRESTRESSED CONCRETE IN RUNWAYS IS DESCRIBED. SPECIAL MIXES OF CONCRETE HAVE BEEN TRIED TO REDUCE THE VARIATION OF TENSIONS UNDER THE INFLUENCE OF TEMPERATURE VARIATIONS. AIR ENTRAINMENT AGENTS ARE NOT REQUIRED IN BELGIUM CONCRETE TO REDUCE FROST AND DEICING SALTS EFFECTS BECAUSE OF THE VERY HIGH DEGREE OF COMPACTION AND HIGH RESISTANCE OF COMPRESSION. THE USE OF WATER REDUCING ADDITIVES, CAN MAKE CONCRETE MORE PLASTIC, THUS EFFECTING MORE EASY PLACING THE SHAPING OF THE SURFACE.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:41:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/121927</guid>
    </item>
    <item>
      <title>LOAD-DEFLECTION CHARACTERISTICS OF SOIL-CEMENT PAVEMENTS</title>
      <link>https://trid.trb.org/View/121691</link>
      <description><![CDATA[A COMPREHENSIVE RESEARCH PROGRAM TO DEVELOP A THICKNESS DESIGN PROCDURE FOR SOIL-CEMENT PAVEMENTS IS IN PROGRESS AT THE LABORATORIES OF THE PORTLAND CEMENT ASSOCIATION. THE PROGRAM HAS BEEN DIVIDED INTO THE FOLLOWING AREAS OF STUDY' /A/ THE ESTABLISHMENT OF A RELATIONSHIP BETWEEN LOAD AND DEFLECTION FOR SOIL-CEMENT PAVEMENT, AND /B/ AN EVALUATION OF THE FATIGUE PROPERTIES OF SOIL-CEMENT. DATA FROM THESE STUDIES MAY BE CORRELATED BY THEORETICAL CONCEPTS TO FORMULATE A THICKNESS DESIGN PROCEDURE. THIS PAPER REPORTS THE FINDINGS OF THE SUDY TO DEVELOP A RELATIONSHIP BETWEEN LOAD AND DEFLECTION FOR SOIL-CEMENT. AN EQUATION WAS DERIVED WHICH PREDICTS LOAD CAPACITY AS A FUNCTION OF DEFLECTION, THICKNESS OF SOIL-CEMENT, RADIUS OF BEARING AREA, AND MODULUS OF SUBGRADE REACTION. NEITHER THE TYPE OF MATERIAL STABILIZED NOR THE CEMENT CONTENT WAS STATISTICALLY SIGNIFICANT IN DETERMINING THE PARAMETERS OF THE EQUATION FOR SOIL-CEMENT. THIS SUGGESTS THAT IF ASTM PROCEDURES ARE FOLLOWED AND PCA CRITERIA ARE MET, A MATERIAL WITH UNIQUE STRUCTURAL CHARACTERISTICS IS PRODUCED. A COMPARISON BETWEEN THE LOAD CAPACITY OF SOIL-CEMENT AND A HIGH-QUALITY GRANULAR MATERIAL INDICATED THAT IF DEFLECTIONS WERE MAINTAINED EQUAL , THE CAPACITY OF SOIL-CEMENT WAS 1.5 TIMES GREATER FOR THE 4-IN. AND 3.3 TIMES GREATER FOR THE 10-IN. BASE THICKNESSES: /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:40:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/121691</guid>
    </item>
    <item>
      <title>APPLICATION OF SOIL SURVEY DATA TO HIGHWAY ENGINEERING IN KANSAS</title>
      <link>https://trid.trb.org/View/121379</link>
      <description><![CDATA[SOIL SURVEYS CONDUCTED BY THE KANSAS HIGHWAY DEPARTMENT ARE DIVIDED INTO THE FOLLOWING THREE TYPES: (1) PRELIMINARY SOIL SURVEYS CONDUCTED IN CONJUNCTION WITH PRELIMINARY PLAN SURVEYS ON LOCATIONS THAT ARE TO BE COMPLETELY REGRADED, (2) AFTER GRADING IS COMPLETED ON EACH PROJECT A SUBGRADE SURVEY IS MADE ON LOCATIONS WHERE A FLEXIBLE SURFACE IS PLANNED TO DETERMINE THE FINAL SUBGRADE STABILITY AND THE BASE AND SURFACE THICKNESS REQUIREMENTS, AND (3) ON A FEW PROJECTS EACH YEAR, HIGH EMBANKMENTS ARE PLANNED ACROSS LOCATIONS WHERE THE FOUNDATION SOILS APPEAR TO BE SO WEAK THAT A SUBSURFACE INVESTIGATION IS DEEMED ADVISABLE TO DETERMINE SAFE FILL HEIGHTS AND SLOPES. PRIMARY USES OF THESE DATA ARE IN: (1) THE COMPUTATION OF EARTH-WORK QUANTITIES, (2) SOIL SELECTION DURING PLAN PREPARATION, (3) THE ADVANCE PREDICTION OF THE APPROXIMATE THICKNESS OF BASE COURSE AND WEARING SURFACE THAT WILL BE REQUIRED TO CARRY EXPECTED TRAFFIC LOADS OVER THE SOILS THAT ARE AVAILABLE FOR SUBGRADE CONSTRUCTION, AND (4) MATERIALS INVESTIGATION AND SURVEY TO ESTIMATE CONSTRUCTION COSTS AND AS A GUIDE IN WRITING PROJECT SPECIFICATIONS.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:39:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/121379</guid>
    </item>
    <item>
      <title>DESIGN CORRELATIONS FOR RED AND KENYA RED-BROWN SOILS</title>
      <link>https://trid.trb.org/View/121314</link>
      <description><![CDATA[PEDOLOGICAL DESIGN CURVES WERE OBTAINED FOR CERTAIN SPECIFIC ROADS IN KENYA COLONY. IT IS OBSERVED THAT IN RELATIVELY YOUNG SOILS, THE PARENT MATERIAL SEEMS TO EXERCISE A CONTROL OVER THE ROAD ENGINEERING PROPERTIES OF ALL HORIZONS OVER THAT MATERIAL. THERE IS THE APPARENT TRANSITION BETWEEN PARENT MATERIAL AND THE SUBSOIL LAYER WHICH TAKES THE FORM: (1) BASIC TUFF YIELDING DECOMPOSED TUFF CONTAINING MAINLY HYDRATED, (2) HALLOYSITE YIELDS DEHYDRATED HALLOYSITE WHERE THE DEGREE OF HYDRATION DECREASES AS THE SURFACE LAYER IS APPROACHED. THE DECOMPOSED TUFF APPEARS TO CONTAIN MONTMORILLONITE BUT THERE IS NO KNOWN RECORD OF THE MONTMORILLONITE PERSISTING IN THE SOILS OVER THAT HORIZON. A LOW CBR SOIL WAS RECENTLY INVESTIGATED TO DETERMINE THE REASON FOR ITS LOW LOAD CARRYING CAPACITY. THOUGH THE SWELLING PRESSURE WAS FOUND TO BE LOW, THE ONLY CLAY MINERALS RECOGNIZED WERE METAHALLOYSITE AND POSSIBLY A SMALL AMOUNT OF HYDRATED HALLOYSITE WITH FELDSPAR AND QUARTZ. AN ATTEMPT WAS MADE TO GROUP THE VARIOUS MATERIALS ON THE BASIS OF THEIR CLAY ACTIVITY, BUT NO RECOGNIZABLE RELATIONSHIP WAS EVIDENT IN RESPECT TO PAVEMENT THICKNESS.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:38:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/121314</guid>
    </item>
    <item>
      <title>A REVIEW AND EVALUATION OF SOIL-CEMENT PAVEMENTS</title>
      <link>https://trid.trb.org/View/120441</link>
      <description><![CDATA[THE FACTORS AFFECTING THE PROPERTIES OF SOIL-CEMENT ARE REVIEWED. QUALITY AND THICKNESS DESIGN PROCEDURES FOR SOIL- CEMENT BASE COURSES ARE CRITICALLY EXAMINED. FIELD TEST SECTION AND AIRFIELD PERFORMANCE DATA ARE ANALYZED AND COMPARED WITH THE PERFORMANCE OF CONVENTIONAL FLEXIBLE PAVEMENTS.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:35:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/120441</guid>
    </item>
    <item>
      <title>STABILIZED SOIL-BOUND SURFACES WITH CALCIUM CHLORIDE AS AN ADMIXTURE</title>
      <link>https://trid.trb.org/View/119585</link>
      <description><![CDATA[A LABORATORY RESEARCH PROJECT ON STABILIZED SOIL MIXTURES WAS CONDUCTED TO STUDY THE FACTORS THAT INFLUENCE THE SERVICE BEHAVIOR OF STABILIZED AND SURFACE-CONSOLIDATED SOIL-AGGREGATE MIXTURES WHEN CALCIUM CHLORIDE IS USED EITHER AS AN ADMIXTURE, OR AS A SURFACE APPLICATION, OR BOTH. THE PHYSICAL CHARACTERISTICS OF GRAVEL WHICH DETERMINED ITS SUITABILITY FOR USE IN SURFACING A ROAD ARE: (1) DURABILITY OF PEBBLES OR ROCK FRAGMENTS, (2) QUALITY OF BINDER, (3) CREATING OF PEBBLES, AND (4) PROPORTION IN WHICH BINDER IS PRESENT. A CIRCULAR TEST TRACK WAS USED TO INVESTIGATE DIRECTLY THE BEHAVIOR OF MATERIALS SUITABLE FOR LOW-COST CONSTRUCTION UNDER CONTROLLED TRAFFIC AND MOISTURE CONDITIONS. COMPARABLE RESULTS ARE GIVEN WHICH ARE PARTICULARLY USEFUL FOR THE FOLLOWING: (1) DETERMINING AND ESTABLISHING LIMITING VALUES FOR THE PRESCRIBED PHYSICAL TEST USED IN GENERAL SPECIFICATIONS FROM MATERIALS FOR STABILIZED BASE AND SURFACE COURSE CONSTRUCTION, (2) INVESTIGATING POSSIBILITIES OF USING SPECIAL MATERIALS AVAILABLE IN ONLY PARTICULAR LOCALITIES, OR OF TREATING THEM TO RENDER THEM SATISFACTORILY SERVICEABLE, AND (3) DETERMINING THE LIMITING FACTORS OF THICKNESS OF WEARING COURSES OF STABILIZED MATERIAL AND CORRELATING THE PROPOSED LABORATORY TESTS WITH VARIOUS DESIGN REQUIREMENTS. RESULTS ARE SUMMARIZED OBTAINED FROM STUDIES OF SAND-CLAY-GRAVEL MATERIALS BOTH TREATED AND NON-TREATED WITH CALCIUM CHLORIDE. IT WAS DETERMINED THAT NON-PLASTIC GRANULAR MIXTURES OF MATERIALS WITH GRADING MEETING THE AASHO SPECIFICATIONS, BUT WITH LOWER PLASTICITY INDICES, MAY BE MAINTAINED IN AN EXCELLENT SERVICEABLE CONDITION WHEN KEPT DAMP BY CAPILLARY WATER SUFFICIENT TO HOLD THE MOISTURE CONTENT AT THE OPTIMUM OF THE MATERIAL IN QUESTION. BECAUSE OF THE GREATER DENSITY AND STABILITY A WELL GRADED SAND- CLAY-GRAVEL HAVING A LOW PLASTICITY INDEX IS PREFERRED TO AN ABSOLUTELY NON-PLASTIC MATERIAL FOR BASE COURSE CONSTRUCTION. BINDING OF AGGREGATES SECURELY IN PLACE WITH STABLE SOIL MIXTURES AND CALCIUM CHLORIDE ELIMINATES MOST OF THE DESTRUCTION AND LOSS OF ROAD MATERIAL DUE TO THE ACTION OF TRAFFIC. CONTROL OF GRADING IS ESSENTIAL TO ENSURE STABILITY. THE USE OF AN EXCESSIVE AMOUNT OF FINE MATERIAL SEEMS TO RETARD OR PREVENT EFFECTIVE COMPACTION.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:24:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/119585</guid>
    </item>
    <item>
      <title>INVESTIGATION AND APPRAISAL OF THE PERFORMANCE OF CEMENT TREATED BASES AS USED IN COMPOSITE PAVEMENTS IN CALIFORNIA</title>
      <link>https://trid.trb.org/View/119420</link>
      <description><![CDATA[ONE HUNDRED SEVENTY-FIVE CLASS A AND CLASS B CEMENT TREATED BASE B (CTB) PROJECTS BUILT BETWEEN 1950 AND 1962 WERE EVALUATED. SIXTY-FOUR PERCENT ARE GIVING EXCELLENT SERVICE, SEVENTEEN PERCENT WERE RATED GOOD, EIGHT PERCENT FAIR AND ELEVEN PERCENT REQUIRED EXTENSIVE MAINTENANCE EARLY IN THEIR DESIGN LIVES. THE MAIN CAUSES OF FAILURE APPEARED TO BE: INSUFFICIENT CEMENT CONTENT, POOR MIXING OF CEMENT, EXCESSIVE TRIMMING OF THE COMPACTED CTB, INSUFFICIENT CTB THICKNESS, INADEQUATE CTB COMPACTION OR DEFICIENCIES IN THE AC SURFACING THICKNESS OR QUALITY. A SIGNIFICANT IMPROVEMENT IN THE PERFORMANCE OF CTB COMPOSITE PAVEMENTS WAS CAUSED BY: (1) EXTENDING THE CTB AT LEAST ONE FOOT INTO THE SHOULDER, (2) PLANT MIXING THE CTB, (3) BUILDING THE PROJECT IN A TEMPERATE CLIMATE, (4) INCREASING THE THICKNESS OF THE AC SURFACING, (5) LIMITING THE COMPACTED THICKNESS OF ANY ONE LAYER OF CTB TO 0.50 FOOT, (6) USING TYPE II CEMENT RATHER THAN TYPE I, (7) USING A MINIMUM CTB THICKNESS OF 0.50 FOOT, AND (8) PROVIDING A MINIMUM IN SITU CTB COMPRESSIVE STRENGTH OF 500 PSI. FIELD SAMPLING OBSERVATIONS SHOWED THERE WAS GENERALLY VERY LITTLE BOND BETWEEN LAYERS OF CTB BUT THE AC WAS NEARLY ALWAYS WELL BONDED TO THE TOP OF THE CTB. EXCESSIVE TRIMMING OF A COMPACTED CTB WAS SHOWN TO CAUSE DISINTEGRATION OF A THIN LAYER AT THE TOP OF THE CTB WHICH SUBSEQUENTLY CAUSED EXTENSIVE PUMPING AND CRACKING OF THE AC SURFACING. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:20:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/119420</guid>
    </item>
    <item>
      <title>GTM METHODS OF TEST FOR SOILS AND BITUMINOUS MIXTURES</title>
      <link>https://trid.trb.org/View/119082</link>
      <description><![CDATA[THE FOLLOWING PHYSICAL PROPERTIES ARE DETERMINED OF ANY PROPOSED AGGREGATE BLEND FOR USE IN THE FLEXIBLE PAVEMENT TO CARRY ANY SPECIFIED WHEEL LOAD: OPTIMUM BITUMEN CONTENT, REQUIRED DENSITY, AND BEARING RESISTANCE. THE GYRATORY TESTING MACHINE IS DESCRIBED AS THE PRIMARY APPARATUS REQUIRED FOR THIS TEST. THE GYRATORY TESTING MACHINE USAGE IS DESCRIBED AS A TEST FOR THE COMPACTION METHOD WHICH IS INTENDED TO PROVIDE RATIONAL COMPACTION REQUIREMENTS FOR FLEXIBLE PAVEMENTS. THE FLEXIBLE PAVEMENT THICKNESS DESIGN TEST IS BASED ON THE PREMISE THAT NO PART OF THE PAVEMENT BASE OR SUBGRADE SHOULD EXPERIENCE A MAXIMUM THEORETICAL SHEAR STRESS THAT IS IN EXCESS OF THE SHEARING STRENGTH AS MEASURED BY THE GYRATORY TESTING MACHINE. THE THEORETICALLY INDUCED MAXIMUM SHEAR STRESS AND THE MEASURED SHEAR STRENGTH ARE PLOTTED VERSES DEPTH BENEATH THE WHEEL CONTACT AREA. IT IS EMPHASIZED THAT THE MAGNITUDE OF THE MEASURED STRENGTH WILL VARY WITH THE AMOUNT OF STRAIN (GYRATORY ANGLE) AND THE SELECTION OF THIS VALUE MUST BE BASED ON ENGINEERING JUDGMENT TAKING INTO CONSIDERATION ENVIRONMENTAL AND STRUCTURAL FEATURES AS WELL AS ANTICIPATED INTENSITY OF TRAFFIC AND DEFLECTION OF THE PAVEMENT.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:11:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/119082</guid>
    </item>
    <item>
      <title>ALABAMA EXPERIENCES WITH PORTLAND CEMENT-TREATED BASES FOR FLEXIBLE PAVEMENTS</title>
      <link>https://trid.trb.org/View/118419</link>
      <description><![CDATA[MIX DESIGN, THICKNESS DESIGN AND COST COMPARISONS ARE MADE. CEMENT FACTORS RANGE FROM 3-1/2 TO 6 PERCENT BY VOLUME - THE AMOUNT REQUIRED TO DEVELOP 400 PSI UNCONFINED COMPRESSIVE STRENGTH AT 7-DAYS ON CYLINDERS MOULDED BY ASSHO T-134. TWO-LAYER SOIL CEMENT DESIGNS ARE DISCUSSED. CONCLUSIONS: CEMENT-TREATED BASES ARE DESIGNES TO MEET STRUCTURAL STRENGTH REQUIREMENTS WITHOUT CEMENT. THE CEMENT IS USED TO PREVENT EXCESSIVE DEFLECTIONS, RUTTING AND LOSS OF RIDING SURFACE; THEY CAN BE PLACED RAPIDLY; CRACKING CAN BE CONTROLLED TO REASONABLE TOLERANCES BY REDUCING CEMENT CONTENT; THE COST OF CEMENT-TREATED BASE IS ONLY SLIGHTLY MORE THAN CONVENTIONAL TYPE BASE.]]></description>
      <pubDate>Sun, 15 Aug 2004 01:54:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/118419</guid>
    </item>
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