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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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>MICHIGANS EXPERIENCE WITH NUCLEAR GAGES FOR MEASURING SOIL COMPACTION</title>
      <link>https://trid.trb.org/View/119536</link>
      <description><![CDATA[MICHIGANS RESEARCH IN NUCLEAR METHODS FOR HIGHWAY FOUNDATION COMPACTION CONTROL IS DESCRIBED FROM ITS INCEPTION IN 1952 THROUGH A MAJOR FIELD EXPERIMENT IN 1955- 66 DURING FREEWAY CONSTRUCTION. THE EQUIPMENT USED IS DISCUSSED AS WELL AS GAGE CALIBRATION PROCEDURES, TRAINING OF INSPECTION PERSONNEL, FIELD TESTING PROCEDURES, AND SAFETY PRECAUTIONS. THE NUCLEAR METHOD HAS PROVED SUITABLE FOR FIELD USE, IN WHICH IT SAVES TIME AND REDUCES OPERATOR FATIGUE. SPECIAL STUDIES, IN ADDITION TO DEVELOPMENT OF THE MICHIGAN COMBINATION DENSITY-MOISTURE GAGE, ARE OUTLINED, INCLUDING EVALUATION OF OTHER EQUIPMENT AND USE OF STATISTICAL CONTROL METHODS. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:23:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/119536</guid>
    </item>
    <item>
      <title>EFFECTS OF TYPE OF MATERIAL ON NUCLEAR DENSITY MEASUREMENTS</title>
      <link>https://trid.trb.org/View/110045</link>
      <description><![CDATA[THE PAPER DESCRIBES LABORATORY AND FIELD INVESTIGATIONS CARRIED OUT TO IMPROVE THE PRACTICAL APPLICATION OF THE NUCLEAR METHOD IN HIGHWAY CONSTRUCTION. VARIOUS FACTORS HAVE BEEN STUDIED, INCLUDING THE EFFECTS OF DENSITY GRADIENT, SOURCE ENERGY, AND PARTICULARLY SOIL TYPE, ON DENSITY MEASUREMENTS. TWO METHODS ARE DESCRIBED FOR THE POSSIBLE ELIMINATION OF THE EFFECT OF SOIL TYPE IN PRACTICAL DENSITY MEASUREMENTS. IN THE FIRST, DIRECT TRANSMISSION IS USED AS AN AUXILIARY TEST WITH BACKSCATTER MEASUREMENTS. RESULTS ARE GIVEN TO ILLUSTRATE THE ADVANTAGES OF THIS METHOD FOR DETERMINING THE CORRECT CALIBRATION CURVE FOR THE BACKSCATTER METHOD AND ALSO FOR THE EVALUATION OF ANY DENSITY GRADIENT IN THE SOIL LAYER. IN THE SECOND METHOD INTRODUCTION OF A CERTAIN AIR GAP BETWEEN THE SURFACE PROBE AND THE SOIL SURFACE IS USED TO OBTAIN A COUNT RATIO WHICH, WHEN PLOTTED AGAINST DENSITY, GIVES A POSITIVE SLOPE RELATIONSHIP INDEPENDENT OF SOIL TYPE FOR DENSITIES UP TO 400 PCF. THIS METHOD ONLY EMPLOYS THE BACKSCATTER TECHNIQUE AND IS THEREFORE COMPLETELY NONDESTRUCTIVE. IT IS SHOWN FURTHER HOW THE AIR-GAP METHOD CAN BE USED FOR EFFECTIVE DENSITY MEASUREMENTS ON SOIL LAYERS. MEASUREMENTS AT PREDETERMINED AIR GAPS FURTHER PERMIT CONTINUOUS RECORDS OF DENSITY TO BE OBTAINED BY USING A SUITABLE RATEMETER. /AUTHOR/]]></description>
      <pubDate>Mon, 12 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/110045</guid>
    </item>
    <item>
      <title>FROST ACTION IN SOILS: A SYMPOSIUM</title>
      <link>https://trid.trb.org/View/128060</link>
      <description><![CDATA[THIS REPORT CONTAINS 35 REPORTS PRESENTED AT A SYMPOSIUM ON FROST ACTION IN SOILS.]]></description>
      <pubDate>Fri, 12 Aug 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/128060</guid>
    </item>
    <item>
      <title>COMPACTION CONTROL WITH MOBILE NUCLEAR RADIATION EQUIPMENT</title>
      <link>https://trid.trb.org/View/96791</link>
      <description><![CDATA[THIS PAPER IS AN EVALUATION OF A MOBILE NUCLEAR RADIATION DEVICE NOW BEING TESTED BY THE SASKATCHEWAN DEPARTMENT OF HIGHWAYS AND TRANSPORTATION. THE DEVICE IS USED FOR FIELD TESTING OF COMPACTION, I.E. MEASURING SUBGRADE AND SURFACING MOISTURE CONTENTS AND DENSITIES. THE RESULTS ARE NOT CONCLUSIVE, BUT INDICATE THE POSSIBILITY OF SUCCESS. /CGRA/]]></description>
      <pubDate>Fri, 29 Jul 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/96791</guid>
    </item>
    <item>
      <title>PRACTICAL APPLICATIONS OF THE AREA CONCEPT TO COMPACTION CONTROL USING NUCLEAR GAGES</title>
      <link>https://trid.trb.org/View/102546</link>
      <description><![CDATA[THE RATE OF PLACEMENT OF EARTHWORK IN HIGHWAY CONSTRUCTION HAS GREATLY EXPANDED SINCE WORLD WAR II; HOWEVER, THE ACCEPTANCE OR REJECTION OF THIS EARTHWORK COMPACTION HAS BEEN BASED ON PREWAR METHODS THAT ARE GEARED TO LOWER PRODUCTION RATES. THE CALIFORNIA DIVISION OF HIGHWAYS HAS BEEN DEVELOPING A NEW TEST METHOD FOR ACCEPTING OR REJECTING EARTHWORK COMPACTION. THIS METHOD HAS THREE IMPORTANT FACETS: /1/ A MODIFIED STATISTICAL APPROACH, /2/ THE USE OF NUCLEAR SOIL GAGES, AND /3/ AN AREA CONCEPT. THE STATISTICAL APPROACH CONSISTS OF OBTAINING SEVERAL IN PLACE DENSITIES OF THE COMPACTED EARTHWORK IN AN AREA TO BE TESTED. THE ACCEPTANCE OR REJECTION IS BASED ON THE AVERAGE RELATIVE COMPACTION AND THE PERCENTAGE FALLING BELOW THE REQUIRED RELATIVE COMPACTION VALUE. THE TEST SITES ARE SOMEWHAT RANDOMLY SELECTED IN AN AREA READY FOR TESTING. THE AREA IS PASSED OR FAILED ACCORDING TO THE TEST RESULTS. THE DENSITY OF THE COMPACTED MATERIAL IS DETERMINED BY USE OF NUCLEAR SOIL MOISTURE AND DENSITY GAGES. THIS NEW TEST METHOD WAS USED EXPERIMENTALLY ON A PROJECT DURING 1964 AND THE RESULTS WERE SATISFACTORY. AFTER SOME MODIFICATION OF THE TEST PROCEDURE IT WAS USED ON SEVERAL PROJECTS IN THE 1965 AND 1966 CONSTRUCTION SEASONS. THIS COMPACTION CONTROL CONCEPT WAS SUCCESSFUL FROM BOTH THE STATE AND CONTRACTORS POINTS OF VIEW. /AUTHOR/]]></description>
      <pubDate>Sun, 20 Feb 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/102546</guid>
    </item>
    <item>
      <title>CONTROL OF MOISTURE CONTENT IN AN AGGLOMERATED MIXTURE BY MEANS OF A SURFACE NEUTRON PROBE /IN GERMAN/</title>
      <link>https://trid.trb.org/View/99501</link>
      <description><![CDATA[DETAILS ARE GIVEN OF MEASURING MOISTURE CONTENT METHODS IN AGGOLMERATED MIXTURES, AND OF THE NEUTRON PROBE USED AND ITS OPERATION. /LCPC/RRL/]]></description>
      <pubDate>Wed, 09 Sep 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/99501</guid>
    </item>
    <item>
      <title>WEST VIRGINIA TEST ROAD - BITUMINOUS MIXTURES STUDIES</title>
      <link>https://trid.trb.org/View/101147</link>
      <description><![CDATA[TEST ROADS WERE CONSTRUCTED IN WEST VIRGINIA TO PROVIDE FIELD DATA TO SUPPLEMENT LABORATORY STUDIES TO: (1) DEFINE THE EFFECT OF MIXING AND PLACEMENT TEMPERATURES ON THE ENGINEERING PROPERTIES OF ASPHALTIC CONCRETE, AND (2) EVALUATE THE ADEQUACY OF A TENTATIVE DESIGN PROCEDURE FOR HOT-MIXED ASPHALTIC CONCRETE IN WEST VIRGINIA. RELATED STUDIES WERE PERFORMED DURING THE CONSTRUCTION OF THE TEST ROAD TO EVALUATE NUCLEAR DENSITY AND AIR PERMEABILITY CONTROL OF PLACEMENT OF BITUMINOUS MIXTURES, BENKELMAN BEAM DEFLECTIONS BEFORE AND AFTER CONSTRUCTION OF THE SURFACING, AND PRELIMINARY STUDIES OF THE EFFECT OF ROLLER PASSES ON COMPACTION OF HOT-MIXED MATERIAL. THE TEST ROAD CONSTRUCTION AND RESULTS OBTAINED ARE BRIEFLY SUMMARIZED. THE PAVEMENT SECTION CONSISTED OF THE FOLLOWING COURSES: (1) 2-IN EXPERIMENTAL WEARING COURSE, (2) 3/4-IN HOT-LAID ASPHALTIC CONCRETE WEARING COURSE OF LIMESTONE, (3) 2-IN HOT-LAID ASPHALTIC CONCRETE BOTTOM COURSE OF LIMESTONE, AND (4) 16-IN CRUSHED STONE BASE. A TYPICAL COOLING CURVE IS PRESENTED WHICH WAS OBTAINED BY THE THERMOCOUPLE MEASUREMENTS OF THE MIXTURE TEMPERATURE AFTER PLACEMENT AND DURING THE FOLLING OPERATION. THIS CURVE ILLUSTRATES THE TYPICAL INCREASE AND THEN DECREASE IN TEMPERATURE THAT OCCURS AT THE TOP RECORDER AND THE GENERAL DECREASE IN TEMPERATURE THAT OCCURS FOR OTHER LEVELS. THE LOSS OF HEAT AT THE MIXTURE SURFACE AND TO THE BASE APPARENTLY KEEPS THE MIDDLE OF THE MIXTURE AT A HIGHER TEMPERATURE THAN THE TEMPERATURES AT THE TOP AND BOTTOM OF THE LAYER THROUGHOUT THE PERIOD OF OBSERVATION. A GYRATORY TESTING MACHINE FOR COMPATION WAS USED OF THE HOT-MIX TO STIMULATE FIELD COMPACTION. LABORATORY COMPACTION WAS ATTAINED BY THE FIXED-ROLLER EQUIPPED GYRATORY TESTING MACHINE USING A ONE-DEGREE ANGLE OF GYRATION, 100 PSI RAM PRESSURE, AND 30 REVOLUTIONS. TABLES ARE PRESENTED WHICH SHOW THE RESULTS OF CORES TAKEN FROM THE VARIOUS TEST SECTIONS WHICH WERE EVALUATED FOR MEAN DENSITY AND STANDARD DEVIATION. CONTINUOUS OBSERVATION OF THE TEST ROAD PAVEMENT SECTIONS SINCE THEIR CONSTRUCTION APPROXIMATELY THREE YEARS AGO WAS PERFORMED. COMPARISON OF THE AIR FLOW RATE VERSUS AIR CONTENT CURVES FOR THE DIFFERENT MIXTURES SHOWED A CONSIDERABLE VARIATION IN AIR VOID CONTENTS FOR ANY SELECTED FLOWRATE VALUE. IF EXACTING COMPACTION CONTROL IS NOT REQUIRED, IT APPEARS THAT AIR VOID CONTENT MAY BE MAINTAINED WITHIN A RANGE OF 4.0 TO 8.0 PERCENT FOR ALL MIXTURES STUDIED IF A FLOW RATE OF 300 ML./MIN. IS USED AS A FIELD CONTROL CRITERION.]]></description>
      <pubDate>Wed, 12 Aug 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/101147</guid>
    </item>
    <item>
      <title>NUCLEAR SUBSURFACE MOISTURE AND DENSITY MEASUREMENTS</title>
      <link>https://trid.trb.org/View/118490</link>
      <description><![CDATA[A QUESTIONNAIRE LETTER WAS SENT TO THE HIGHWAY RESEARCH DEPARTMENTS OF THE 50 STATES, THE DISTRICT OF COLUMBIA, PUERTO RICO, AND OTHER GOVERNMENTAL AGENCIES BY THE OKLAHOMA DEPARTMENT OF HIGHWAYS TO DETERMINE THE EXPERIENCE OF THESE ORGANIZATIONS IN UTILIZING NUCLEAR EQUIPMENT FOR MEASURING SUBSURFACE MOISTURE AND DENSITY VARIATIONS. THE HIGHWAY RESEARCH BOARD SUGGESTED FOUR TECHNIQUES FOR ACCESS TUBE INSTALLATION AND LISTED PROBLEMS ASSOCIATED WITH EACH METHOD: (1) DRILLING A HOLE AND INSERTING THE ACCESS TUBE, (2) DRILLING WITH A SMALL AUGER INSIDE THE ACCESS TUBE AS IT IS INSERTED INTO THE SOIL, (3) FORCING CLOSED TUBING TO A DESIRED DEPTH, AND (4) FORCING OPEN-END TUBING FOR THREE TO FOUR FEET, ALLOWING MATERIAL TO ENTER THE BOTTOM OF THE TUBE. IT WAS DECIDED TO USE PROCEDURES USED IN MISSISSIPPI, WHICH WERE OUTLINED IN A REPORT ENTITLED "A METHOD OF INSTALLING ACCESS TUBES FOR SOIL MOISTURE MEASUREMENT BY THE NEUTRON PROCEDURE", JOHN KOZACHYN AND J. ROGER MCHENRY. THE NUCLEAR EQUIPMENT USED CONSISTED OF: (1) ELECTRONIC SCALER, (2) DEPTH DENSITY PROBE, AND (3) DEPTH MOISTURE PROBE. THIRTY TEST SITES WERE INSTALLED. THE PERFORMANCE OF THE DRILLING EQUIPMENT WAS SATISFACTORY. WHEN USING THE PRESCRIBED PROCEDURE, IT WAS POSSIBLE TO DRILL THREE HOLES, INSTALL ACCESS TUBES, AND TAKE INITIAL DATA READINGS IN A 4 TO 6 HOUR PERIOD. IT IS CONCLUDED THAT THIS EQUIPMENT PROVIDES A SATISFACTORY METHOD OF INSTALLING TEST SITES FOR MEASUREMENT OF SUBSURFACE SOIL MOISTURE AND DENSITY WITH NUCLEAR INSTRUMENTS.]]></description>
      <pubDate>Mon, 09 Feb 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/118490</guid>
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