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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
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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>A Generalized Investigation of Potentially Poor Soil Support by Regional Geomorphic Units within the Adjacent 48 States : Preprint</title>
      <link>https://trid.trb.org/View/1219075</link>
      <description><![CDATA[This report qualitatively assesses the potential for poor soil support within the adjacent 48 states. For each of 97 physiographic sections, an estimate was made of: (a) the frequency of occurrence of organic deposits, and (b) the combined frequency of occurrence-severity rating of clayey deposits. In order to assess the regional character of the poor support problem, a national soil textural map was developed. Frequency of occurrence ratings for organic deposits were determined directly from this map for each section. For clayey deposits, a severity scale, based upon a relationship between the soil texture and the Unified Soil Classification System, was combined with the frequency of occurrence rating of clayey deposits obtained from the national soils map. The poor support potential was rated at five levels: (VW) very widespread, (M-W) medium to widespread, (L-M) limited to medium, (N-L) non-existent to limited, and (NE) non-existent. The study indicated the limited regional distribution of organic terrain in the Adjacent 48 States. This distribution is concentrated in youthful (geomorphic) glacial and coastal terrain due to the rather poorly integrated drainage system often associated with these regional geomorphic areas. Although clayey deposits occur throughout the Adjacent 48 States, the greater concentration of them is east of the Rocky Mountains. The climatic, topographic and parent material factors are generally more favorable in the latter areas for the development of clay minerals.]]></description>
      <pubDate>Wed, 19 Dec 2012 09:01:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1219075</guid>
    </item>
    <item>
      <title>Stabilization of Marginal Soils Using Recycled Materials</title>
      <link>https://trid.trb.org/View/782959</link>
      <description><![CDATA[Loose sand, soft clays, and organic deposits are often unsuitable for use in construction due to their less-than-desirable engineering properties. Traditional methods of stabilizing these soils through in-situ ground improvement or replacement techniques are costly. Recycled materials such as scrap tires, plastics, ash, slag, and construction debris provide a viable alternative both for their relatively lower cost and desirable engineering properties. Furthermore, use of recycled materials prevents their disposal into landfills, which are approaching capacity in Florida and across the nation. This report provides a comprehensive assessment of various recycled materials that can be used to stabilize marginal soils in Florida. Particular attention is given to material availability and environmental properties in addition to engineering properties. A methodology is proposed to guide Florida Department of Transportation (FDOT) personnel in evaluating, testing, and approving any new material for use as a highway construction material.]]></description>
      <pubDate>Tue, 27 Jun 2006 10:26:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/782959</guid>
    </item>
    <item>
      <title>SURFACE CHEMICAL FACTORS OF IMPORTANCE IN THE HARDENING OF SOILS BY MEANS OR PORTLAND CEMENT</title>
      <link>https://trid.trb.org/View/122056</link>
      <description><![CDATA[THE RESULTS SHOW:(1) THAT THE SURFACE-CHEMICAL ALONG WITH OTHER PHYSICAL FACTORS INFLUENCE THE HARDENING OF CLAY SOILS WITH PORTLAND CEMENT, (2) THAT IONIC TREATMENT CAN IMPROVE THE HARDENING ACTION, (3) THAT THE DIFFERENCE BETWEEN THE OPTIMUM MOISTURE CONTENT AND SHRINKAGE LIMIT OF INORGANIC CLAY SOILS IS A MEASURE OF ITS SUSCEPTIBILITY TO STABILIZATION, (4) THAT THE WATER AFFINITY AND THE ACCESSIBILITY OF THE INTERNAL SURFACE OF THE SOIL-CEMENT SYSTEM CONTROLS ITS BEHAVIOR IN THE WET-DRY TESTS, (5) THAT THE PERMEABILITY OF THE SYSTEM AND THE AMOUNT OF PORE SPACE FILLED WITH UNADSORBED WATER DETERMINES ITS BEHAVIOR IN THE FREEZING AND THAWING TESTS, AND (6) THAT ORGANIC MATTER OF AN ACID NATURE AFFECTS THE SOIL-CEMENT SYSTEM ADVERSELY.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:41:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/122056</guid>
    </item>
    <item>
      <title>CONSTRUCTION ON MARSHLAND DEPOSITS: TREATMENTS AND RESULTS</title>
      <link>https://trid.trb.org/View/121703</link>
      <description><![CDATA[FOUR FIELD CASES ARE EXAMINED OF POST-CONSTRUCTION SETTLE- MENTS OF STRUCTURES /BUILDINGS AND PAVED AREAS/ BUILT OVER COMPRESSIBLE ORGANIC SOIL DEPOSITS /MARSHLANDS/. LABORATORY TESTS SHOW THAT THESE SOILS EXHIBIT SUBSTANTIAL RATES OF SECONDARY COMPRESSION. ALL SITES WERE STABILIZED BY SURCHARGE FILLS, ONE SITE INVOLVED THE USE OF SAND DRAINS. TWO ADJOINING BUILDINGS ARE COMPARED, ONE WITH SAND DRAINS AND ONE WITHOUT. SURCHARGE SETTLEMENT RECORDS AND PIEZOMETER DATA ARE EVALUATED TO ESTIMATE THE EFFECTIVE CONSOLIDATION PRESSURES WHICH WERE ACHIEVED DUE TO SURCHARGING.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:40:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/121703</guid>
    </item>
    <item>
      <title>AN ENGINEERING GROUPING OF NEW YORK STATE SOILS</title>
      <link>https://trid.trb.org/View/121302</link>
      <description><![CDATA[DURING THE PAST YEAR THE BUREAU OF SOIL MECHANICS HAS PREPARED FOR THE NEW YORK STATE DEPARTMENT OF PUBLIC WORKS ENGINEERING SOIL MAPS FOR CURRENT PROJECTS COVERING A TOTAL OF 3,360 SQUARE MILES. A DISCUSSION IS PRESENTED OF THE ENGINEERING SOIL GROUPING USED IN NEW YORK STATE, THE DEVELOPMENT OF SOIL MAPS, AND THE APPLICATION OF THE MAPS AS AIDS IN PRESENTING THE SOIL INFORMATION FOR HIGHWAY DESIGN AND CONSTRUCTION. THE ENGINEERING GROUP OF NEW YORK STATE SOILS IS BASED UPON THE FOLLOWING: (1) THE DIVISION OF THE STATE INTO ITS PHYSIOGRAPHIC PROVINCES WITH ANALYSES OF THE GEOLOGIC HISTORY, TOPOGRAPHY, SOIL, ROCKS, AND HIGHWAY PROBLEMS ASSOCIATED WITH EACH PROVINCE, AND (2) A GROUPING OF THE SOILS ON THE BASIS OF THEIR DEPOSITION, PARENT MATERIAL, SOIL AND ROCK PROFILE, LAND FORM AND DRAINAGE CHARACTERISTICS AS THESE FACTORS AFFECT HIGHWAY PROBLEMS. THE ENGINEERING SOIL MAPS ARE PREPARED TO SHOW THE AREAL DISTRIBUTION OF SOILS TO BE ENCOUNTERED IN THE PARTICULAR REGION. THE MAPS ARE ASSEMBLED ON THE BASIS OF EXISTING SOIL AND GEOLOGIC INFORMATION AND WITH THE AID OF AERIAL PHOTOGRAPHS. SOIL DEPOSITS, ARE GROUPED AS GLACIAL AND POST- GLACIAL AND ARE FURTHER DIVIDED INTO GLACIAL ICE DEPOSITS, GLACIAL STREAM DEPOSITS, GLACIAL LAKE DEPOSITS, GLACIAL MARINE DEPOSITS, WEATHERED BED ROCKS, RECENT STREAM DEPOSITS AND ORGANIC DEPOSITS. THE GROUPING AT THE PRESENT TIME CONSISTS OF THE FOLLOWING: THICK TILL, THIN TILL, DRUMLINS, MAJOR MORAINES, OUTWASH, KAME FIELDS, ESKERS, LAKE BOTTOM SEDIMENTS, DELTAS, BARS AND BEACHES, MARINE BOTTOM SEDIMENTS, RESIDUAL, ALLUVIAL, MUCK AND PEAT, MEADOW, AND MUCK OVER MARL. THE ENGINEERING SOIL MAPS FORM A PART OF BOTH THE PRELIMINARY AND FINAL SOIL REPORT FOR EACH PROJECT AND CONSTITUTE A BASIS FOR THE PLANNING, CONTROL AND REVIEW OF SOIL WORK IN THE DESIGN AND CONSTRUCTION OF HIGHWAYS. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:38:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/121302</guid>
    </item>
    <item>
      <title>ANALYSIS OF PLASTICS BY ATR SPECTROSCOPY</title>
      <link>https://trid.trb.org/View/106802</link>
      <description><![CDATA[A BRIEF DISCUSSION IS PRESENTED OF THE PRINCIPLES OF THE ATTENUATED TOTAL REFLECTANCE (ATR) METHOD. THE ATR METHOD OF INFRARED SPECTROSCOPY HAS PROVIDED THE INDUSTRIAL SPECTROSCOPIST WITH A METHOD OF ANALYSIS FOR DIFFICULT OR IMPOSSIBLE TO HANDLE SAMPLES. IN THE ATR ACCESSORY UNIT, THE SAMPLE IS PLACED IN CONTACT WITH A PRISM WHICH IS IN TURN PLACED IN THE SAMPLE BEAM AREA OF THE SPECTROPHOTOMETER. THE MIRRORS AND PRISM IN THE OPTICAL PATH OF THE ATR UNIT ARE MOUNTED ON ROTATABLE STAGES ENABLING THE ANGLE OF INCIDENT RADIATION TO BE VARIED FROM 40 TO 65 DEG. IN ORDER TO OBTAIN THE MOST USEFUL SPECTRUM OF THE SAMPLE. WHEN A BEAM OF RADIATION ENTERS THE PRISM AND IS TOTALLY REFLECTED FROM ONE FACE, THERE IS AN EXCHANGE OF ENERGY BETWEEN THE PRISM AND THE SAMPLE SINCE THE SAMPLE IS IN INTIMATE CONTACT WITH ONE FACE OF THE PRISM. SOME OF THE ENERGY INCIDENT ON THE TOTALLY REFLECTING INNER SURFACE OF THE PRISM ESCAPES AND PENETRATES A FEW MICRONS INTO THE SURFACE OF THE SAMPLE. THE ENERGY EXCHANGE IS APPROXIMATELY INVERSELY PROPORTIONAL TO THE INDEX OF REFRACTION OF THE SAMPLE. THE PRISM MATERIAL MUST HAVE A HIGHER INDEX OF REFRACTION THAN THE SAMPLE. A KRS-5 PRISM HAS BEEN USED IN THE WORK REPORTED. IT IS THALLIUM BROMIDE-IODIDE AND HAS AN INDEX OF REFRACTION OF 2.380, WHICH IS HIGHER THAN MOST ORGANIC MATERIALS. FROM APPLICATIONS REVIEWED, IT IS CONCLUDED THAT ATR IS PARTICULARLY VALUABLE FOR SURFACE STUDIES, SUCH AS THOSE ON THE EPOXY CIRCUIT BOARDS AND CELLULOSE ACETATE BUTYRATE DESCRIBED. THE ATR TECHNIQUE MAY BE USED TO DETECT ORGANIC CONTAMINATION ON A SUBSTRATE IF THE ABSORPTION BANDS FROM THE MATERIAL OF INTEREST ARE OF SUFFICIENT INTENSITY TO PRESENT A USABLE SPECTRAL CURVE, AND THE ABSORPTION BANDS FROM THE MATERIAL ARE DIFFERENTIATED FROM ANY ARISING FROM THE SUBSTRATE. THE METHOD HAS BEEN USED TO DETERMINE THE TYPES OF PLASTICIZERS IN THERMOPLASTICS SUCH AS CELLULOSE ACETATE BUTYRATE. EXPERIMENTAL EVIDENCE INDICATES THAT ATR SHOULD PROVE FEASIBLE IN DETERMINING THE DEGREE OF CURE OF EPOXY SYSTEMS BY SURFACE STUDIES OF THE SOLID, CURED MATERIAL.]]></description>
      <pubDate>Thu, 10 Mar 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/106802</guid>
    </item>
    <item>
      <title>ORGANIC IMPURITIES IN SAND THAT INTERFERE WITH THE HYDRATION OF PORTLAND CEMENT: A TEST FOR DETECTING THEIR PRESENCE</title>
      <link>https://trid.trb.org/View/95555</link>
      <description><![CDATA[AS A RESULT OF THE INVESTIGATION, IT WAS CONCLUDED THAT: (1) THE TEST PROVIDES A SIMPLE AND RAPID METHOD THAT WOULD DISTINGUISH BETWEEN CONTAMINATED AND UNCONTAMINATED SANDS. HOWEVER, THE DISTINCTION WAS NOT CLEARLY DEFINED AND WAS MASKED BY THE EXPERIMENTAL ERROR BETWEEN LABORATORIES. THEREFORE, ONLY SANDS GIVING PH VALUES ABOVE 12.4 OR BELOW 12.2 COULD BE PLACED IN DISTINCT CATEGORIES. CONSEQUENTLY SANDS WITH PH VALUES BETWEEN 12.2 AND 12.4 WERE PLACED IN A BORDER-LINE CATEGORY. (2) THE REPRODUCIBILITY OF THE PH RESULTS WITHIN A LABORATORY WAS ONLY PLUS OR MINUS 0.05 PH UNITS AND BETWEEN LABORATORIES IT WAS PLUS OR MINUS 0.1 PH UNITS. (3) SANDS IN THE BORDER-LINE CATEGORY COULD BE ASSESSED BY HEATING THEM AT 600 DEGREES C FOR ONE HOUR. IF THE RESULTING INCREASE IN PH WAS MORE THAN 0.2 PH UNITS THEY WERE CONTAMINATED. (4) THE SUSCEPTIBILITY OF PORTLAND CEMENT TO ORGANIC CONTAMINATION VARIED FROM BATCH TO BATCH. CEMENTS THAT WERE LESS SUSCEPTIBLE TO ORGANIC CONTAMINATION WERE NOT SUITABLE FOR THE TEST AND COULD BE ELIMINATED BY DETERMINATION OF THE PH THAT THEY GAVE WHEN MIXED WITH A STANDARD SAND CONTAMINATED WITH 0.4 PER CENT OF TANNIC ACID. /AUTHOR/]]></description>
      <pubDate>Sun, 16 Jan 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/95555</guid>
    </item>
    <item>
      <title>EFFECT OF OPERATING CONDITIONS OF THE PARTICULATES FROM A SINGLE CYLINDER DIESEL ENGINE</title>
      <link>https://trid.trb.org/View/195670</link>
      <description><![CDATA[Particulates were collected from the exhaust of a single cylinder diesel engine at different speeds and fuel-air equivalence ratios.  The filters were rated to capture 99.99% of all particulates greater than 0.3 microns in diameter.  Samples were taken at 1500 RPM and equivalence ratios varying from about 0.2 to 0.7, and at an equivalence ratio of about 0.3 and engine speeds varying from 1000 to 2500 RPM.  A base point with an equivalence ratio of 0.3 with an engine speed of 1500 RPM was repeated several times to establish the expected test variation of the particulate data.  The particulate properties investigated were the total mass of particulate produced per mass of fuel burned, the mass fraction of extractable organic material in the sample, and the mutagenic potency of the extract as measured by a bacterial bioassay.  Variation in fuel-air ratio (engine load) affected the particulate and extractable organic production much more than variations in engine speed.  The ratio of mass of particulates produced was three to four times higher at both high and low equivalence ratios, than in the equivalence ratio range between 0.3 and 0.6.  At low equivalence ratios, the particulates has a soluable fraction approximately five times higher than mid-range.  The soluable fraction decreased rapidly until the equivalence ratio reached 0.4 remaining relatively constant above that point.  The mutagenic potency of the extract was constant across both speed and equivalence ratio ranges within the accuracy of the bioassay.]]></description>
      <pubDate>Fri, 30 Sep 1983 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/195670</guid>
    </item>
    <item>
      <title>SOME FACTORS AFFECTING THE PROPERTIES OF UNSTABILIZED LAYERS, ESPECIALLY GRAVEL WEARING COURSES. A STUDY OF LITERATURE</title>
      <link>https://trid.trb.org/View/77098</link>
      <description><![CDATA[A study of international literature concerning the properties of unstabilized layers, especially gravel wearing courses, was carried out.  The following main factors were studied: particle size distribution, the quality of gravel and binder soil and their effect on bearing and wear properties.  The influence of organic materials coming from roadsides at grading maintenance is dealt with.  Effects of dust binder on matrerial properties is discussed. /TRRL/]]></description>
      <pubDate>Wed, 28 Mar 1979 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/77098</guid>
    </item>
    <item>
      <title>ALTERNATE FUELS FOR AUTOMOBILES</title>
      <link>https://trid.trb.org/View/60351</link>
      <description><![CDATA[Research on alternative fuels relating to alcholol, fuel from biomass, gasoline of modified composition, hydrogen, and synthetic fuels are reported.  Studies have confirmed the feasibility of using alcholo/gasoline blends as well as neat alcohols in engines; the major problems relate to fuel volatility anbd cold starts.  The 2 alcohols under investigation are ethyl alcohol and methyl alcohol. Research in Brazil has centered on the fermentation products of sugar cane.  Two bioconverson processes with commercial potential are: anaerobic digestion of organic waste to generate methane and bacterial fermentation to yield ethanol.  Research is also underway to formulate a special gasoline blend optimized for starting and first mile economy.  An important consideration in alternate fuel research is fuel tolerance; it would be advantageous to use more than one fuel in emergencies.  Feasibility studies indicate: gasoline from oil shale, distillate oils from oil shale or coal and gasoline/alcohol blends for near term (through 1985); gasoline from coal or oil shale, distillate oils from coal or oil shale and methanol from coal for the mid term (1985-2000); and gasoline from coal or oil shale, distillate oils from coal or oil shale, methanol from coal and hydrogen for the far term (beyond 2000).]]></description>
      <pubDate>Tue, 27 Dec 1977 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/60351</guid>
    </item>
    <item>
      <title>A GENERALIZED INVESTIGATION OF POTENTIALLY POOR SOIL SUPPORT BY REGIONAL GEOMORPHIC UNITS WITHIN THE CONTERMINOUS 48 STATES</title>
      <link>https://trid.trb.org/View/121659</link>
      <description><![CDATA[FOR EACH OF 97 PHYSIOGRAPHIC SECTIONS, AN ESTIMATE WAS MADE OF (A) THE FREQUENCY OF OCCURRENCE OF ORGANIC DEPOSITS AND (B) THE COMBINED FREQUENCY OF OCCURRENCE-SEVERITY RATING OF CLAYEY DEPOSITS. IN ORDER TO ASSESS THE REGIONAL CHARACTER OF THE POOR SUPPORT PROBLEM, A NATIONAL SOIL TEXTURAL MAP WAS DEVELOPED. FREQUENCY OF OCCURRENCE RATINGS FOR ORGANIC DEPOSITS WERE DETERMINED DIRECTLY FROM THIS MAP FOR EACH SECTION. FOR CLAYEY DEPOSITS, A SEVERITY SCALE, BASED ON A RELATIONSHIP BETWEEN THE SOIL TEXTURE AND THE UNIFIED SOIL CLASSIFICATION SYSTEM, WAS COMBINED WITH THE FREQUENCY OF OCCURRENCE RATINGS OF CLAYEY DEPOSITS OBTAINED FROM THE NATIONAL SOILS MAP. THE STUDY INDICATED THE LIMITED REGIONAL DISTRIBUTION OF ORGANIC TERRAIN IN THE 48 STATES. THIS DISTRIBUTION IS CONCENTRATED IN YOUTHFUL (GEOMORPHIC) GLACIAL AND COASTAL TERRAIN DUE TO THE RATHER POORLY INTEGRATED DRAINAGE SYSTEM OFTEN ASSOCIATED WITH THESE REGIONAL GEOMORPHIC AREAS. ALTHOUGH CLAYEY DEPOSITS OCCUR THROUGHOUT THE 48 STATES, MOST ARE FOUND EAST OF THE ROCKY MOUNTAINS BECAUSE THE CLIMATIC, TOPOGRAPHIC, AND PARENT MATERIAL FACTORS ARE GENERALLY MORE FAVORABLE THERE. /AUTHOR/]]></description>
      <pubDate>Tue, 16 May 1972 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/121659</guid>
    </item>
    <item>
      <title>CONQUEST OF THE DARIEN</title>
      <link>https://trid.trb.org/View/121444</link>
      <description><![CDATA[A MEANS OF UNITING THE AMERICAS BY LAND COMMUNICATION HAS BEEN FRUSTRATED BY THE INACCESSIBILITY OF THE VAST JUNGLE REGION ADJOINING THE REPUBLICS OF PANAMA AND COLOMBIA IN THE REGION KNOWN AS THE DARIEN GAP. THE BUREAU OF PUBLIC ROADS NEGOTIATED AN AGREEMENT WITH THE COLOMBIAN MINISTER OF PUBLIC WORKS PERMITTING RECONNAISSANCE SURVEYS IN 1964 OF THE ATRATO SWAMPS. THESE STUDIES AND THE SUBSEQUENT DETAILED GEOPHYSICAL SURVEYS CONDUCTED ARE DESCRIBED. THE ATRATO RIVER SWAMPS ARE APPROXIMATELY 65 TO 100 K WIDE AND MORE THAN 250 K LONG. ALL SOURCES OF AERIAL PHOTOGRAPHY, AND PARTIAL PHOTOGRAPHIC COVERAGE OF THE AREA WERE ASSEMBLED AND STEREOSCOPIC EXAMINATION AND PHOTOGRAPHIC INTERPRETATION MADE OF THESE UNCONTROLLED EARLY PHOTOGRAPHS. INFORMATION FROM THESE PHOTOGRAPHS LED TO THE SELECTION OF FIVE POSSIBLE ROUTE LOCATIONS THAT MET THE CRITERIA ESTABLISHED FOR THE LEAST DIFFICULT CROSSINGS OF THE SWAMP. THE FIVE SELECTED ROUTES WERE DELINEATED ON THE UNCONTROLLED PHOTOMOSIAC AND COMPARATIVE INTERPRETATION OF THE FIVE TENTATIVE ROUTES WAS PLANNED USING AERIAL INFRARED IMAGERY. THE INFRARED IMAGERY OBTAINED DID NOT CONTAIN SUFFICIENT THERMAL DIFFERENCES TO REVEAL SUBSURFACE CONDITIONS AND MATERIALS. THE ONLY OTHER ALTERNATIVE WAS VISUAL INSPECTION ON THE GROUND IN THE SWAMP BY HELICOPTER ACCESS. A LIMITED GEOPHYSICAL SURVEY WAS UNDERTAKEN, UTILIZING ELECTRORESISTIVITY METHODS AUGMENTED BY SOUNDINGS WITH A PEAT SAMPLER AND BY PROBING. THESE TESTS LEAD TO THE CONCLUSION THAT THE HIGHWAY CROSSING OF THE SWAMP APPEARED FEASIBLE. IN 1967, THE DARIEN SUBCOMMITTEE OF THE PAN AMERICAN HIGHWAY CONGRESS PROVIDED FUNDING AND REQUESTED THE BUREAU OF PUBLIC ROADS TO DIRECT THE COMPREHENSIVE GEOPHYSICAL STUDIES OF THE ATRATO AREA. THREE METHODS OF CONSTRUCTION ARE CONSIDERED ACCEPTABLE ALTHOUGH THE FIRST IS RECOMMENDED AS LEAST COSTLY: (1) PLACEMENT OF FILL MATERIAL OBTAINED FROM THE LOMAS LAS AISLADAS AND THE HILLS WEST OF THE ATRATO RIVER ON THE ROGANIC MAT WITH CONSEQUENT COMPRESSION OF THE ORGANIC MATERIAL AND THE SOFT SUBSURFACE LAYERS, (2) REMOVAL OF ORGANIC MATERIAL AND THE SOFTER SUBSURFACE MATERIAL AND REPLACEMENT WITH FILL MATERIAL OBTAINED FORM THE LOMAS LAS AISLADAS, AND (3) USE OF TRESTLE CONSTRUCTION ACROSS THE ENTIRE SWAMP.]]></description>
      <pubDate>Mon, 09 Mar 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/121444</guid>
    </item>
    <item>
      <title>SOIL STABILIZATION BY CHEMICAL METHODS</title>
      <link>https://trid.trb.org/View/119604</link>
      <description><![CDATA[ATTEMPTS TO FIND A GENERAL FORMULATION OF SODIUM ADDITIVES FOR ALL SOIL TYPES BY COMBINING SODIUM HYDROXIDE AND SODIUM SULFITE AT VARIOUS MOLAR RATIOS HAVE NOT BEEN SUCCESSFUL. PRETREATMENT OF HEAVY CLAYS WITH 1% OCTYLAMINE OR FERRIC CHLORIDE (0.1%) INCREASES THE STRENGTH OF CLAY STABILIZED WITH 5% CEMENT AND 1% SODIUM HYDROXIDE BY REDUCING THE VOLUME EXPANSION OF SOIL DURING IMMERSION. THE REMOVAL OF ORGANIC MATTER FROM AN ORGANIC-CONTAINING SAND CONFIRMS THE BELIEF THAT THE ORGANIC MATTER PRESENT IN THE SAND IS THE ONLY REASON FOR THE INEFFECTIVENESS OF TREATMENT OF THIS SOIL WITH CEMENT AND PREVIOUSLY USED ADDITIVES. CALCIUM SULFATE ANHYDRITE, GYPSUM, AND MAGNESIUM SULFATE ARE VERY EFFECTIVE IN INCREASING STRENGTH OF ORGANIC SAND STABILIZED WITH CEMENT. STUDY OF THE EFFECTS OF SODA-TO-SILICA RATIO IN SODIUM SILICATES AS ADDITIVES TO CEMENT-STABILIZED SILT INDICATES THAT THE SILICATES OF HIGH SODA CONTENT ARE VERY EFFECTIVE IN STRENGTH IMPROVEMENT.]]></description>
      <pubDate>Mon, 16 Feb 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/119604</guid>
    </item>
    <item>
      <title>AN INVESTIGATION OF SOIL ORGANIC MATTER ON THE SETTING OF ORDINARY PORTLAND CEMENT - CHEMICAL STUDIES ON THE ACTIVE FRACTION</title>
      <link>https://trid.trb.org/View/122088</link>
      <description><![CDATA[THE NATURE OF THE ORGANIC COMPOUNDS IN SOIL THAT AFFECT THE HARDENING OF ORDINARY PORTLAND CEMENT (IN SOIL-CEMENT) IS DESCRIBED. HUMIC ACID CONTAINED A FRACTION THAT IS PARTICULARLY ACTIVE TOWARDS CEMENT. FULVIC ACID WILL ALSO RETARD THE HARDENING OF CEMENT. THE MAIN CONCLUSION IS: THE ACTIVE COMPOUNDS IN SOIL ORGANIC MATTER ARE COMPOUNDS OF THE HYDROXY-QUINONE TYPE WHICH BIND METAL IONS SUCH AS CALCIUM, AND THIS PROPERTY IS PROBABLY THE CAUSE OF THE ACTIVITY OF THE SOIL COMPOUNDS TOWARDS CEMENT. THE ABILITY TO IMMOBILIZE CALCIUM IONS MIGHT BE THE BASIS FOR A RAPID TEST TO DETECT THE PRESENCE OF DELETERIOUS ORGANIC MATTER.]]></description>
      <pubDate>Mon, 16 Feb 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/122088</guid>
    </item>
    <item>
      <title>STABILIZED SOIL ROAD BASE</title>
      <link>https://trid.trb.org/View/122073</link>
      <description><![CDATA[A BRIEF DESCRIPTION IS GIVEN OF STABILIZING A MIXTURE OF GRAVEL AND INORGANIC CLAY OF HIGH PLASTICITY. ORGANIC MATTER HAS 4% PH VALUES OF 6 TO 7.5. SITE CROSSED OLD PASTURE FIELDS AND SUBSOIL WAS HEAVY WITH NITRATES SO A DRESSING OF PERMANGANATE OF POTASH WAS FIRST GIVEN. SOIL WAS STABILIZED WITH 8% PORTLAND CEMENT AND 2% CALCIUM CHLORIDE APPLIED PARTLY IN SOLUTION AND PARTLY IN POWDER FORM.]]></description>
      <pubDate>Mon, 19 Jan 1970 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/122073</guid>
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