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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>TRANSAMAZONICA'S GEOTECHNICS</title>
      <link>https://trid.trb.org/View/122985</link>
      <description><![CDATA[THIS PAPER CORRELATES GEOLOGICAL, PEDOLOGICAL AND GEOTECHNICAL DATA OF THE SECTION ESTREITO (STATE OF MARANHAO) - ITAITUBA (STATE OF PARA) OF THE TRANSAMAZONICA HIGHWAY.  THE SECTION ESTREITO - ITAITUBA HAS AN EXTENSION OF 1,240 KM, AND CORRESPONDS TO A PIONEER SETTLEMENT IN THE MIDDLE OF THE AMAZONICA JUNGLE.  GENERAL CHARACTERISTICS OF THE REGION ARE DESCRIBED, INCLUDING GEOGRAPHICAL SITUATION, CLIMATE, VEGETATION AND GEOLOGY.  AN ASSOCIATION IS MADE BETWEEN THE DIFFERENT TYPES OF SOILS, WHICH HAVE BEEN IDENTIFIED IN THE PEDOLOGICAL SURVEY PERFORMED BY THE INSTITUTO DE PESQUISAS AGROSPECURIO DO NORTE - IPEAN, WITH VARIOUS FORMATIONS LITHOLOGY, AS ALL SOILS ARE RESIDUAL, EXCEPT THE GREAT RIVERS ALLUVIAL TERRACES.  CORRELATION IS ALSO MADE BETWEEN THE PEDOLOGICAL AND GEOTECHNICAL CHARACTERISTICS OF THE DIFFERENT TYPES OF SOILS. GOETECHNICAL CHARACTERISTICS ARE PRESENTED OF ROCK EMERGENCES, WHICH ARE TO BE USED AS QUARRIES.  THE CONCEPT OF LATERITE AND LATERITIC SOILS IN BRAZIL IS PRESENTED TOGETHER WITH THE GEOTECHNICAL CHARACTERISTICS OF SOME OCCURRENCES OF THOSE SOILS.  CONSIDERATIONS ARE MADE ABOUT THE UTILIZATION OF LATERITIC CONCRETIONS IN BITUMINOUS SURFACING.  A MEANINGFUL EXAMPLE OF THAT UTILIZATION IS COMMENTED UPON, SUGGESTING THE POSSIBILITY OF THAT UTILIZATION IN THE TRANSAMAZONICA'S FUTURE PAVEMENT.  AN EXPERIENCE PERFORMED IN THE TRANSAMAZONICA FOR THE BITUMINOUS STABILIZATION OF THE PRIMARY SURFACING IS DESCRIBED.  /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 18:44:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/122985</guid>
    </item>
    <item>
      <title>PRINCIPLES OF THE CLASSIFICATION OF ARABLE SOILS</title>
      <link>https://trid.trb.org/View/121060</link>
      <description><![CDATA[THE GENETIC BASIS FOR THE CLASSIFICATION OF ARABLE SOD-PODZOLIC SOILS SHOULD BE THEIR SUBDIVISION ACCORDING TO DEGREE OF DEVELOPMENT OF THE SOD PROCESS /THE INTENSITY OF WHICH CORRESPONDS GENERALLY TO THE PROCESS OF CULTIVATION/, THE PODZOLIC PROCESS, AND SURFACE ABLATION. ZONAL SOIL FORMATION IN AGRICULTURAL SOILS MEANS THAT GRASSLAND AND ARABLE PODZOLIC SOILS SHOULD BE JOINED INTO SOME SORT OF LARGE TAXONOMIC UNIT OF CLASSIFICATION. NATURAL AND ARABLE SOILS SHOULD BE SUBDIVIDED AT DIFFERENT TAXONOMIC LEVELS FOR DIFFERENT SORTS OF THESE SOILS. FURTHER SUBDIVISION OF THE GENERAL GROUP OF ARABLE SOILS OF THE FOREST ZONE SHOULD BE BASED ON A GEOGRAPHIC-GENETIC CLASSIFICATION. ONLY WHEN THIS IS DONE WILL IT BE POSSIBLE TO DEFINE THE ARABLE SOILS ACCORDING TO THEIR DEGREE OF CULTIVATION. THIS PROBABLY SHOULD FOLLOW DIVISION INTO GENERA, WHICH, OF COURSE, ARE DISTINGUISHED ON THE BASIS OF THE SOIL-FORMING PARENT MATERIAL. /AUTHOR/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:37:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/121060</guid>
    </item>
    <item>
      <title>LATERITE AND LATERITIC SOIL IN COASTAL NATAL SOUTH AFRICA</title>
      <link>https://trid.trb.org/View/120990</link>
      <description><![CDATA[A DESCRIPTION IS GIVEN OF THE DISTRIBUTION AND CHARACTERISTICS OF A VESICULAR LATERITE ASSOCIATED WITH THE EARLY CAINOZOIC EROSION SURFACE IN COASTAL NATAL, TOGETHER WITH THE CHEMICAL AND MINERALOGICAL CHARACTERISTICS OF THE SOIL FORMED BY ITS DECOMPOSITION. THE RELATIONSHIP BETWEEN CYCLIC EROSION SURFACES, THE LATERITE, PRE-WEATHERING, AND THE DOMINANCE OF PARENT MATERIAL IN SOIL FORMATION IN COASTAL NATAL CLEARLY INDICATE THE DEPENDENCE OF THE PROCESSES OF SOIL FORMATION ON THE GEOMORPHIO HISTORY OF THIS REGION. /RRL/A/]]></description>
      <pubDate>Sun, 15 Aug 2004 02:37:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/120990</guid>
    </item>
    <item>
      <title>FOUNDATION EXPLORATION</title>
      <link>https://trid.trb.org/View/120554</link>
      <description><![CDATA[CONTENTS: SOIL FORMATION SOIL IDENTIFICATION EXPLORATION AIMS RECONNAISSANCE GEOPHYSICS BORINGS SAMPLING FIELD TESTS LOGGING PROGRAM REFERENCES]]></description>
      <pubDate>Sun, 15 Aug 2004 02:35:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/120554</guid>
    </item>
    <item>
      <title>AIRPHOTO INTERPRETATION OF ENGINEERING SOILS OF INTERSTATE ROUTE I-65 IN TIPPECANOE, CLINTON AND BOONE COUNTIES, INDIANA</title>
      <link>https://trid.trb.org/View/118916</link>
      <description><![CDATA[THIS STUDY PROVIDES AN ENGINEERING SOILS STRIP MAP ALONG A PROPOSED INTERSTATE ROUTE, THAT CAN BE USED FOR PLANNING A DETAILED SOIL SURVEY, FOR MATERIALS LOCATION, TO PREDICT CONSTRUCTION PROBLEMS AND FOR OTHER USES RELATING TO HIGHWAY CONSTRUCTION. THIS IS PART OF AN OVERALL PROGRAM FOR PREPARING ENGINEERING SOIL MAPS ON A COUNTY BASIS. THE ENGINEERING SOILS MAPS PRESENTED WERE PREPARED BY AIRPHOTO INTERPRETATION METHODS ON A PHOTO MOSAIC BASE AT AN APPROXIMATE SCALE OF ONE INCH REPRESENTING 1500 FEET /1/18,000/. THE MAPPED SOIL AREAS ARE GENERALLY DESIGNATED BY LAND FORMS SUCH AS SAND DUNES, RIDGE MORAINES AND TERRACES. NO FIELD CHECKS OR SOIL EXPLORATIONS WERE MADE OF THE MAPPED AREAS. A DESCRIPTION IS GIVEN OF THE PHYSIOGRAPHY , TOPOGRAPHY AND GEOLOGY OF THE AREA AS WELL AS GENERALIZED PROFILES OF THE SOIL AREAS OUTLINED ON THE MAP. VARIOUS LAND FORMS AND ENGINEERING SOIL AREAS ENCOUNTERED ALONG THE ALIGNMENT ARE ALSO DESCRIBED.]]></description>
      <pubDate>Sun, 15 Aug 2004 02:07:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/118916</guid>
    </item>
    <item>
      <title>FACTORS AFFECTING THE FREQUENCY DISTRIBUTION OF CLAY MINERALS IN SOILS</title>
      <link>https://trid.trb.org/View/127983</link>
      <description><![CDATA[AN EXTENSIVE SURVEY OF THE CLAY MINERALS AND THE OTHER MINERAL COLLIODS OF MANY SOILS LED TO THE CONCLUSIONS THAT THE CHEMICAL ENVIRONMENT THAT EXISTS IN A SOIL DURING ITS DEVELOPMENT DETERMINES THE KIND OF CLAY MINERALS THAT ARE BEING FORMED AND THAT THE FREQUENCY DISTRIBUTION OF THE CLAY MINERALS AND THE OTHER MINERAL COLLOIDS, EXCLUSIVE OF THOSE INHERITED FROM THE PARENT MATERIAL, ARE DETERMINED BY THE CHEMICAL ENVIRONMENT OCCURRING DURING SOIL FORMATION. FUTHERMORE, THE CHEMICAL ENVIRONMENT ALSO DETERMINES THE NATURE AND EXTENT OF THE ALTERATION THAT BIOTITE AND MUSCOVITE UNDERGO DURING BREAKDOWN TO COLLOIDAL DIMENSIONS. BECAUSE THE CHEMICAL ENVIRONMENT OF A SOIL IS DETERMINED BY THE FACTORS OF SOIL FORMATION, A GOOD CORRELATION EXISTS BETWEEN THESE FACTORS AND THE FREQUENCY DISTRIBUTION OF THE CLAY MINERALS. ANY OF THE FACTORS OF SOIL FORMATION THAT FUNCTION TO MAINTAIN A NEUTRAL OR AN ALKALINE ENVIRONMENT AND TO ACCUMULATE CACO ALSO INDUCE THE FORMATION AND ACCUMULATION OF MONTMORILLONITE--WHETHER THIS FORMATION IS THROUGH SYNTHESIS OR THROUGH THE ALTERATION OF MICAS AND VERMICULITES. ANY OF THE FACTORS, HOWEVER, THAT FUNCTION TO MAINTAIN A HIGHLY BASE-DEPLETING ENVIRONMENT, SUCH AS HIGH RAINFALL, GOOD DRAINAGE AND A HIGH PERMEABILITY, OR THE POSITION OF A SOIL IN THE PROFILE AS SURFACE HORIZONS, ARE CONDUCIVE TO KAOLINITE AND HALLOYSITE FORMATION. ANY OF THE FACTORS THAT FUNCTION TO MAINTAIN AN INTERMEDIATE ENVIRONMENT, I.E. BETWEEN A HIGHLY ACCUMULATING AND A HIGHLY DEPLETING ONE, INDUCE THE FORMATION OF VERMICULITE EITHER BY SYNTHESIS OR BY THE ALTERATION OF THE MICAS. /AUTHOR/]]></description>
      <pubDate>Fri, 11 Aug 2000 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/127983</guid>
    </item>
    <item>
      <title>USE OF SOIL-CEMENT IN DEEP FOUNDATIONS</title>
      <link>https://trid.trb.org/View/476520</link>
      <description><![CDATA[Superficial porous collapsible soils reaching several meters in depth may be found in large portions of the Brazilian territory, particularly in the Federal District region.  This collapsible and weak layer generally leads to the adoption of deep foundations, even for relatively low loads.  In these cases, the load capacity of conventional deep foundations, such as auger bored piles or caissons in concrete, is generally overestimated when compared to the external loads.  In order to reduce costs, the University of Brasilia together with local firms, has been studying the use of soil-cement as a structural element for deep foundation submitted to axial loads up to 400 kN.  Such a limit has been fixed on an economical basis.  This paper presents results of laboratory and field tests on soil-cement piles. Numerical analyses comparing the influence of the relative stiffness of the materials on the soil-structure interface behavior are also presented.]]></description>
      <pubDate>Thu, 05 Mar 1998 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/476520</guid>
    </item>
    <item>
      <title>EFFECT OF DEGREE OF WEATHERING ON DYNAMIC PROPERTIES OF RESIDUAL SOILS</title>
      <link>https://trid.trb.org/View/469184</link>
      <description><![CDATA[The process of soil formation in the tropics is very different than the same process in more temperate regions.  Weathering processes intensify in warm and humid climates that are prevalent in tropical regions.  Chemical weathering processes that dominate in these regions, such as decomposition and dissolution, are fairly well understood.  The effect this weathering has on the physical, mechanical, and dynamic properties of the rock/soil is not completely clear.  Investigators present laboratory results and correlations that reveal behavioral trends caused by the effects of weathering on residual soil from the western coast of Puerto Rico.  The study focuses on the dynamic shear modulus and material damping ratio of both natural and remolded samples for low- to mid-level amplitudes of vibration.  Better understanding of these effects will lead to more accurate prediction of phenomena, such as soil amplification that may trigger landslides in these soil formations.  A computerized resonant column device was used in the study.  Correlations and empirical formulations are presented that show the effects that the degree of weathering has on the dynamic properties of these residual soils for undisturbed and remolded samples.]]></description>
      <pubDate>Wed, 01 Jan 1997 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/469184</guid>
    </item>
    <item>
      <title>HIGHWAYS AS ENVIRONMENTAL ELEMENTS</title>
      <link>https://trid.trb.org/View/104040</link>
      <description><![CDATA[THE HISTORY OF HIGHWAY DEVELOPMENT IS REVIEWED WITH THE CONCLUSION GIVEN THAT WE HAVE DEVELOPED AN ENCYCLOPEDIA OF GEOMETRIC DESIGN PRINCIPLES THAT MADE ROADS GOOD FOR VEHICLES IF NOT FOR PEOPLE. STIMULATED BY THE PROJECTED INTERSTATE HIGHWAY SYSTEM, THE CONCEPT WAS RECOGNIZED THAT HIGHWAYS WERE NOT MERELY PAVEMENTS IN SELECTED RIGHT-OF-WAY CORRIDORS BUT IMPORTANT ELEMENTS IN THE ENVIRONMENTS THEY PASS THROUGH. THE PRINCIPLES OF ENVIRONMENTAL DESIGN ARE AIMED AT CREATING ORDER AMONG ITS INTERRELATED PARTS. GEOMORPHOLOGY PRODUCES BOTH REGIONAL AND LOCAL CHARACTERISTICS WHICH GIVE EACH LAND AREA DISTINCTIVE FORM AND TOGETHER WITH ITS VEGETATIVE MANTLE CREATES A FUNCTIONAL AND VISUAL STABILITY NECESSARY TO MANS PHYSICAL WELL BEING AND MENTAL HEALTH. HIGHWAY LOCATIONS SHOULD BE DEVELOPED IN RELATION TO PERMANENT RATHER THAN TRANSITORY FEATURES. WE NEED FINALLY TO ACCEPT THE FACT THAT WE ARE DEALING WITH A SOCIAL ENVIRONMENT AS WELL AS A PHYSICAL ONE AND THAT A SOCIAL ENVIRONMENT IS TIED AS CLOSELY TO VISUAL VALUES AS IT IS TO ECONOMICS AND TECHNOLOGY.]]></description>
      <pubDate>Mon, 12 Dec 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/104040</guid>
    </item>
    <item>
      <title>RELATIONSHIPS BETWEEN THE DAILY TEMPERATURE WAVE AND THE DEVELOPMENT OF THE NATURAL SOIL PROFILE</title>
      <link>https://trid.trb.org/View/128154</link>
      <description><![CDATA[MORAINES ARE INVESTIGATED WHICH ARE MIXTURES OF CALCAREOUS AND SILICEOUS MATERIALS. THE FIRST PHASE OF SOLUTION WEATHERING IS A DECALCIFICATION. THE REMNANT IS A COLLOIDAL CLAYEY SUBSTANCE THAT IN TEMPERATE CLIMATES IS AT FIRST QUITE MOBILE. THIS SUBSTANCE CHARACTERIZES THE FUNDAMENTAL PROCESS OF SOIL FORMATION THAT IS OF SPECIAL INTEREST IN THIS CONNECTION: THE LESSIVAGE OR CLAY PERMEATION. THE REGULARITY IN THE VARIATION OF SOIL DEVELOPMENT WITH VARIATION IN EXPOSURE CONDITION, AND THE CONSTANCY OF THE BOUNDARY BETWEEN THE UPPER AND LOWER SOIL HORIZONS AT ABOUT 40 CM, RENDER PAIRS OF OPPOSITE DRUMLIN FLANKS FAVORABLE OBJECTS FOR THE STUDY OF THE INFLUENCE OF THE COURSE OF SOIL TEMPERATURE ON SOIL FORMATION. FOR THIS PURPOSE A FOREST-FREE DRUMLIN, NAMED THE WALZENBERG, LOCATED AT THE VILLAGE BOUNDARY OF ALLENSBACH, WAS CHOSEN. THE MICROCLIMATIC INVESTIGATIONS ARE BASED ON THE FOLLOWING CONDITIONS: (1) THE TWO TEST AREAS ARE SITUATED AT AN ELEVATION OF 450 AND 500 M ABOVE SEA LEVEL, IN THE UPPER THIRD OF THE UNFORESTED DRUMLIN, SLOPES OF AN AVERAGE SLOPE ANGLE OF 20 DEGREES TOWARD SOUTHWEST-SOUTH AND NORTHEAST-NORTH, RESPECTIVELY, (2) THE ARTIFICIAL FILLING OF RAW LIME-RICH MORAINE MATERIAL HAS A SINGLE-GRAIN STRUCTURE OF GOOD PERMEABILITY, AND IS NONPLASTIC AND HARDLY SUSCEPTIBLE TO EROSION, AND (3) THE SURFACES OF THE ARTIFICIAL SOIL FILLS WERE FITTED TO THE NATURAL SLOPE AND WERE KEPT CONTINUOUSLY FREE OF VEGETATION. THE FOLLOWING MICROCLIMATIC FACTORS WERE DETERMINED: (1) SOIL TEMPERATURES AT DEPTHS OF 2, 5, 10, 20, 35, 50, 75 AND 100 CM BY CONTINUOUS MECHANICAL RECORDING, (2) PRECIPITATION AND SEEPAGE WATER, AND (3) DRAINAGE. THESE INVESTIGATIONS OF SOIL TEMPERATURES ON BOTH SLOPES OF THE WALZENBERG PRODUCED THE FOLLOWING PRELIMINARY RESULTS:(1) ANALYSIS OF THE 4 GEOTHERM FIELDS RENDERED A GIVEN THERMAL PROFILE, (2) WITH THE AID OF TAUTOCHRONES, A DIVISION INTO 3 PARTS WAS VISUALIZED: THE FANNING OUT OF THE TAUTOCHRONES IN THE ACTIVE UPPER ZONE, THE BOUNDARY LAYER WITH THE LOCALIZED TEMPERATURE INVERSION DURING THE NIGHT HOURS, AND THE ALIGNMENT OF THE TAUTOCHRONES IN THE SAME DIRECTION IN THE PASSIVE LOWER ZONE, AND (3) THE OVERVIEW OBTAINED WITH REGARD TO THE COURSE OF SOIL TEMPERATURES DURING THE GROWING SEASON BY MEANS OF SELECTED TAUTOCHRONE PAIRS LEADS TO THE RECOGNITION OF SUBDIVISIONS THAT ARE FUNCTIONS OF TIME.]]></description>
      <pubDate>Thu, 25 Aug 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/128154</guid>
    </item>
    <item>
      <title>PATTERNED GROUND IN SOUTHEASTERN NEWFOUNDLAND</title>
      <link>https://trid.trb.org/View/128141</link>
      <description><![CDATA[PATTERNED GROUND IS PRESENT AND ACTIVE ON THE AVALON PENINSULA OF NEWFOUNDLAND, THOUGH IN THE MAIN IT IS RESTRICTED TO HIGHER EXPOSED AREAS OF THE SOUTHERN HALF OF THAT PENINSULA. THE PATTERNED GROUND FORMS RESEMBLE TYPES PREVIOUSLY CONSIDERED CONFINED, IF AT LOW ELEVATIONS, TO MORE NORTHERLY LATITUDES. ALSO, A PERMAFROST BASE HAD BEEN ASSUMED NECESSARY FOR CONSTRUCTION OF CERTAIN STRUCTURES, BUT THERE IS PRESENTLY NO PERMAFROST ANYWHERE ON THE AVALON PENINSULA. FORMATION OF THE PATTERNED GROUND WAS CAUSED LARGELY BY LOW SUMMER TEMPERATURES, GENERAL THINNESS OR ABSENCE OF SNOW COVER IN WINTER AND A STRONGLY MARITIME CLIMATE. THOSE FACTORS, WHERE COMBINED WITH SPARSE VEGETATION, AND A HARD TILL UNDERLYING FROST-CHURNED SOILS, CAN PRODUCE THE MOST TYPICAL PATTERNED GROUND FORMS. PRESENCE OF SUCH WELL-DEVELOPED FEATURES ON THE AVALON PENINSULA INDICATES THAT FOSSIL FROST STRUCTURES ELSEWHERE SHOULD NOT EVERYWHERE BE ASSUMED TO INDICATE MUCH MORE SEVERE CLIMATE, PERHAPS WITH PERMAFROST, IN THE PAST. THEY MAY MERELY INDICATE AN EARLIER, INTENSELY MARITIME-TYPE CLIMATE WITH A MODERATE WINTER, BUT LOW MEAN ANNUAL TEMPERATURE. /AUTHOR/]]></description>
      <pubDate>Thu, 24 Mar 1994 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/128141</guid>
    </item>
    <item>
      <title>EFFECT OF WETTING AND DRYING ON SHEAR STRENGTH</title>
      <link>https://trid.trb.org/View/167406</link>
      <description><![CDATA[Climatic changes, such as repeated wetting and drying over geological ages, lead to the degeneration of the parent rock to form soil.  Simultaneously these actions can also cause some aggregation of soil particles and the production of bonds, called desiccation bonds, which impart an intrinsic effective stress to the soil.  This intrinsic effective stress can influence the shear strength behavior of soils subjected to such climatic actions.  When a soil is subjected to repeated wetting and drying in the laboratory, an intrinsic effective stress is imparted to it which results in greater shear strength and in a stiffer stress-strain response.  This intrinsic effective stress may be attributed to chemical bonds.  (ASCE)]]></description>
      <pubDate>Wed, 16 Sep 1981 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/167406</guid>
    </item>
    <item>
      <title>NEW LOGGING FOR EXPLORATORY BORING BY MEANS OF ULTRASONIC WAVE REFLECTION</title>
      <link>https://trid.trb.org/View/35637</link>
      <description><![CDATA[The reflection of ultrasonic short waves on the sides of soil formations gives echo characteristic of their acoustic impedance. The reflected intensity   can be related to the velocity of sound, and the density and porosity of reflecting layers. A measuring probe, to which a transducer and an electronic system for picking the signals have been attached, was developed for investigating shaft walls. A computer program was written for interpreting the measurements. It takes into account the theoretical relations, which define the principles of the method and the data characteristics of the materials encountered. The ultrasonic reflection charts obtained for two shafts, translated into porosity as a function of the levels, are correlated with standard nuclear porosity logging and laboratory measurements or cores taken from those shafts. The comparative results are very satisfactory. It was also shown that the signal received is a function of the permeability. /TRRL/]]></description>
      <pubDate>Wed, 21 Apr 1976 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/35637</guid>
    </item>
    <item>
      <title>GROUTING HEATHROW'S NEW TUBE</title>
      <link>https://trid.trb.org/View/34714</link>
      <description><![CDATA[This short article describes the stabilization of the sandy gravel above the new Piccadilly Line station tunnels at Heathrow Airport.  The soil formation comprises 5m of water-bearing sandy gravel overlying clay, the crown of the twin 7.5 diameter tunnels coinciding approximately with the top of the clay.  A series of 80 grout holes were drilled in a fan-shaped arc across the entire width of the twin tunnels.  A multi-sleeved grout tube was fitted in each hole for the two-stage grouting operation, the tube being sealed into the ground with a bentonite/cement sleeve grout. Primary injections of a cement/bentonite grout were followed by a chemical-solution grout consisting of sodium silicate and mixed esters, which filled the remaining pores and provided an impermeable mass of high strength.  /TRRL/]]></description>
      <pubDate>Thu, 19 Feb 1976 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/34714</guid>
    </item>
    <item>
      <title>ROCK WEATHERING AND SOIL FOUNDATION</title>
      <link>https://trid.trb.org/View/39851</link>
      <description><![CDATA[The phenomenon of rock weathering is described in simplified but complete terms.  Also described are the ways in which forces and agents of nature can change relatively dense, solid rock materials into relatively loose, fragmented soil materials and how the composition and structure of the rock compares with the composition and structure of the resulting soil.  The contribution of mechanical, biological and chemical processes are delineated with a thorough description and discussion of the role played by chemical processes.  The relative contributions of climate, topographic relief, and rock composition and structure to the process of weathering are discussed and the overriding importance of climate and topograohic relief is demonstrated.  The paper concludes with a description of typical soil profiles that develop in North American climates.]]></description>
      <pubDate>Tue, 30 Sep 1975 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/39851</guid>
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