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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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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <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>Unmanned soil sampling vehicle path planning based on improved genetic algorithm with dynamic A* algorithm</title>
      <link>https://trid.trb.org/View/2598693</link>
      <description><![CDATA[Unmanned sampling vehicles encounter path planning challenges due to complex terrain and vehicle kinematics constraints; hence, this paper proposes an Improved Genetic Algorithm (IGA) path planning method. The study frames the soil sampling path optimisation problem as a Single Depot Multi-Traveller Problem with capacity constraints (SDMTSP) and develops a three-chain encoding. Strategies such as a curvature penalty mechanism, adaptive cross-variance strategy and dynamic population management enhance global search capability. A* algorithm employs an improved heuristic function and eight-neighbourhood search for local optimisation, alongside segmented spline interpolation for path smoothing. Experiments demonstrate that the paths formulated by the improved genetic algorithm are shortened by 19.20%, 20.12% and 3.59% compared to the Particle Swarm Algorithm (PSO), traditional Genetic Algorithm (GA) and swarm ant algorithm (ACO), respectively, while also exhibiting strong robustness. This method can offer an efficient and safe path planning scheme for the automated operation of unmanned soil sampling vehicles.]]></description>
      <pubDate>Mon, 05 Jan 2026 09:54:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/2598693</guid>
    </item>
    <item>
      <title>Performance of GCL after 10 Years in Service in the Arctic</title>
      <link>https://trid.trb.org/View/1314256</link>
      <description><![CDATA[The performance of a geosynthetic clay liner (GCL) installed as part of a geocomposite barrier (geomembrane/GCL) to contain a hydrocarbon spill adjacent to the Arctic Ocean was evaluated by examining sacrificial samples exhumed after 1, 4, 6, 7, and 10 years in service. The hydraulic and chemical characteristics of the GCL were most affected by the location within the soil profile relative to the water table (typically about 1.3 m below ground level). The bentonite in the GCL samples exhumed from a depth of 0.0-0.8 m was well hydrated with a dispersed structure. Despite the significant cation exchange that took place between these GCL samples and the surrounding soil (the percentage of the exchangeable sodium decreased from 68% to 10-15%), there was no change in the hydraulic conductivity (k) of GCL for tap water or jet fuel. A similar bentonite structure was observed for GCL samples exhumed from 0.8 to 1.3 m below ground level; however, an observed network of horizontal and vertical microcracks (200-400 μm wide) in the bentonite layer was attributed to the formation of ice lenses. As a result, the k of these GCL samples increased by one to two orders of magnitude when permeated by both tap water and jet fuel. The bentonite in GCL samples exhumed from below the water table after 6 and 10 years was flocculated with relatively high free pore space. The k values of these samples increased by one to four orders of magnitude for tap water and jet fuel. Despite this increase in k at some depths, there was no evidence of migration of hydrocarbons through the barrier over the last 10 years, indirectly suggesting that the subsurface geocomposite barrier system is still performing well.]]></description>
      <pubDate>Thu, 24 Jul 2014 15:21:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1314256</guid>
    </item>
    <item>
      <title>Current Practices in Soil Sampling</title>
      <link>https://trid.trb.org/View/1285658</link>
      <description><![CDATA[No abstract]]></description>
      <pubDate>Mon, 27 Jan 2014 10:14:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/1285658</guid>
    </item>
    <item>
      <title>Evaluating Compaction Quality Using Elastic Seismic P Wave</title>
      <link>https://trid.trb.org/View/1250446</link>
      <description><![CDATA[Seismic refraction using the longitudinal or P wave method of survey was carried out at some highway locations with the object of evaluating the compaction quality of subgrade and subbase at the locations. These highways traverse different geologic terrain. The survey delineated two layers in most of the locations with various values of velocities that generally increase with depth. Soil samples were also obtained for the different subgrades. Compaction and classification tests were carried out on the soil samples. Seismic refraction theory was reviewed and was used to obtain a profile of the layers. The profile pattern of the layers was found to be indicative of the quality of compaction of the subgrade.]]></description>
      <pubDate>Wed, 22 May 2013 13:07:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/1250446</guid>
    </item>
    <item>
      <title>Seismic Response Characteristics of Saturated Sand Deposits Mixed with Tire Chips</title>
      <link>https://trid.trb.org/View/1247025</link>
      <description><![CDATA[With the objective of better and more environmentally friendly recycling methods, many researchers are now examining the use of scrap tires as a new geomaterial. Based on past research, it was clear that tire chips reduce the rise of excess pore-water pressure when subjected to earthquake shaking. Based on such characteristics, online pseudodynamic response tests were conducted in this study on model grounds consisting of either tire chip-mixed sand or alternating layers of sand and tire chips with the aim of clarifying the seismic response characteristics of tire chips and tire chip-sand mixtures. Online testing is a method of feeding soil response characteristics directly from soil samples into a one-dimensional modeling algorithm. The test results showed that when tire chips with low stiffness were either mixed with sand or placed as layers, more significant damping and seismic isolation effects were observed. The presence of tire chips also reduced the accumulation of excess pore-water pressure in the layer, preventing the occurrence of liquefaction. In addition, when tire chips are installed as layers beneath the sand, liquefaction is not generated in the upper sandy layer because the amplitudes of the seismic waves are attenuated. Finally, the effectiveness of tire chips mixed with sand increased as the mix ratio was increased. When they were installed as pure layers, tire chips were more effective when placed at a deeper location or when the layer was thicker.]]></description>
      <pubDate>Mon, 15 Apr 2013 13:14:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/1247025</guid>
    </item>
    <item>
      <title>Development of Electronic Miniature Cone Penetrometer and Penetration Test in Silty Clay</title>
      <link>https://trid.trb.org/View/1110098</link>
      <description><![CDATA[A new kind of electronic miniature cone penetrometer is developed for miniature cone penetration test (MCPT), with which the cone penetration resistance and penetration depth can be acquired automatically. In order to form homogeneous soil specimens for MCPT, a new experimental facility is designed. A series of MCPTs in silty soil are carried out and it is found that, for silty soil, the curves of the penetration resistance vs. the depth have no correlation with the cone angles. For MCPTs in silty clay, the initial segment of the penetration curve is straight and the cone tip resistance tends to be stable when the cone is intruded into a certain depth, i.e. the critical depth. For silty clay, the critical depth effect of the cone tip resistance is related with the different failure mechanism of soil under different confining pressure. The relation between the characteristic values of the penetration curve and soil strength parameters is analyzed. The cone resistance factor is linear with the tangent of the internal friction angle of soil. The ultimate cone penetration resistance is found to be closely related to the critical depth.]]></description>
      <pubDate>Mon, 08 Aug 2011 14:21:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/1110098</guid>
    </item>
    <item>
      <title>Analysis of FWD Data and Characterization of Airfield Pavement Materials in New Mexico</title>
      <link>https://trid.trb.org/View/1104864</link>
      <description><![CDATA[This paper describes in detail the laboratory and field evaluation of runways at two airports: Double Eagle II at Albuquerque and Sierra Blanca at Ruidoso, New Mexico. Field skid resistance test, Falling Weight Deflectometer (FWD) test, and coring are carried out. Cores and soil samples are collected and tested in the laboratory. The CBR values and the skid numbers were compared to the tables in Advisory Circulars 150/5320-6D and 150/5320-12C to make an assessment. The modulus values from FWD data are presented in a 2D contour plot to determine the distress area of each runway. The structural health of the pavement of runway 17-35 at Double Eagle II airport is in a good condition while runway 4-22 of the same airport is not in good condition based on the resilient modulus and CBR values. As for Sierra Blanca airport, runway 6-24 is in a good condition while the surface of the runway 12-30 needs attention.]]></description>
      <pubDate>Tue, 28 Jun 2011 15:07:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/1104864</guid>
    </item>
    <item>
      <title>Strength and Deformation Characteristics of Lagoonal Clay Deposits in Lixia River Area by Seismic Piezocone Tests</title>
      <link>https://trid.trb.org/View/968052</link>
      <description><![CDATA[The results of a site investigation on the soft, normally to slightly overconsolidated, Lixia River Lagoonal clay deposit underlying several expressway lines based on seismic piezocone penetration tests (SCPTUs), undisturbed soil sampling from an adjacent borehole, and laboratory tests, are reported here. SCPTU data were used both in the determination of soil profile and the interpretation of strength and deformation properties. The investigation demonstrated a close agreement between strength parameters derived from the field vane tests, and laboratory tests and interpreted SCPTU parameters with a cone factor of Nkt = 16.5. Comparison of the results reveals the validity of SCPTU tests to interpret the strength and deformation properties of Lixia River Lagoonal clay deposits.]]></description>
      <pubDate>Wed, 13 Oct 2010 14:53:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/968052</guid>
    </item>
    <item>
      <title>Development and Validation of the Downhole Freestanding Shear Device (DFSD) for Measuring the Dynamic Properties of Clay</title>
      <link>https://trid.trb.org/View/912674</link>
      <description><![CDATA[The Downhole Freestanding Shear Device (DFSD) is an innovative tool developed for in situ measurement of dynamic properties (modulus and damping) of clay soils over a broad range of strains. The device essentially performs laboratory-quality torsional shear testing on a “freestanding” column of soil carved below the bottom of a borehole. Other shear testing modes may also be accommodated. The DFSD design and testing procedure minimizes sample disturbance by maintaining estimated values of the original in situ effective stress throughout the sample preparation, instrumentation, and testing processes. As a result, the sample is not significantly unloaded, and therefore does not experience the stress-relief disturbance associated with the removal and reapplication of stresses. This report documents design, development and validation work that has yielded a field-capable prototype DFSD tool that is capable of meeting or exceeding the best current laboratory testing capabilities for measurement of dynamic properties of clay soils used in earthquake site response analysis. Mechanical, pneumatic, electrical and sensor systems used to remotely create a test specimen, maintain continuous control of its anisotropic stress state, and test the specimen over a wide strain range of shear strain are described. Validation tests comparing DFSD results to state-ofthe-art laboratory results are presented as well as results from a series of tests that quantify and compare reduced sample disturbance caused by the DSFD relative to conventional high-quality sampling methods.]]></description>
      <pubDate>Fri, 19 Feb 2010 10:57:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/912674</guid>
    </item>
    <item>
      <title>Remediation of the SR 15 Welcome Center Landslide</title>
      <link>https://trid.trb.org/View/902610</link>
      <description><![CDATA[This paper will discuss a 2004 landslide that resulted in the closure of the southbound lanes of SR 15 in northern Tioga County approximately one half mile north of the Pennsylvania Welcome Center and 6 miles south of the New York State border. The landslide measured approximately 800 feet along the head scarp and 400 feet from the head scarp to the toe. Total vertical displacement at the head scarp was approximately 20 feet. Forty‐four borings were drilled to investigate the subsurface conditions in the area of the landslide. Soil samples collected from the borings were tested in the laboratory to estimate the engineering properties of the site soils. The tests included direct and triaxial shear. Inclinometer casing was installed in 13 of the borings, and piezometers were constructed in 12 of the borings. The computer program PASTABL was used to perform the slope stability analyses. Numerous alternatives were considered to remediate the landslide. The selected alternative included: realignment of SR 15 and Park Hill Road, load reduction (excavation) at the landslide head, construction of a soil berm at the toe, and placement of a chimney (blanket) drain behind the toe berm. Construction was completed in 2007 for a cost of approximately 3 million dollars. Inclinometer readings continue to be obtained to monitor the area.]]></description>
      <pubDate>Wed, 21 Oct 2009 08:29:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/902610</guid>
    </item>
    <item>
      <title>Laboratory Subgrade Resilient Modulus Design Values for Michigan</title>
      <link>https://trid.trb.org/View/880976</link>
      <description><![CDATA[The Michigan Department of Transportation (MDOT) currently uses several different procedures for estimating the resilient modulus (MR) of the roadbed soil.  Therefore, MDOT sponsored a research study to develop a consistent and unified procedure to determine MR of the roadbed soil that meets the requirements of the various design-levels of the American Association of State and Highway Transportation Official (AASHTO) Mechanistic-Empirical Pavement Design Guide (M-E PDG).  To do this, the State of Michigan was divided, by soil type, into 15 clusters and 99 areas.  From most areas, disturbed and undisturbed roadbed soil samples were collected and Falling Weight Deflectometer (FWD) tests were conducted. The samples were then tested in the laboratory to determine their natural moisture contents, grain size distributions, Atterberg limits and MR using cyclic load triaxial tests. Statistical analysis were conducted and empirical correlations were developed relating the MR value for the different soil types to their moisture contents, grain size distributions, dry unit weights, and Atterberg limits. The resulting equations can be used for design levels I and II of the M-EPDG. These equations are presented and discussed in this paper. Results of the FWD tests and backcalculation of the MR values of the roadbed soils are presented elsewhere.]]></description>
      <pubDate>Mon, 16 Mar 2009 07:22:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/880976</guid>
    </item>
    <item>
      <title>Development of a Sampler for Measurement of Gas Content in Soils</title>
      <link>https://trid.trb.org/View/796169</link>
      <description><![CDATA[The problem of wave-induced liquefaction is an important feature in coastal and marine engineering, and is one of the main research topics in the European Union project Liquefaction around Marine Structures (LIMAS). In this context, the gas content of a soil is one topic of interest, as the presence of gas influences the pore pressure response and the gradient distribution in the seabed during wave action. The main objective of the work described herein has been to develop a new sampler that enables in situ measurement of gas content in the seabed, and at the same time retrieves a representative sample of the soil. The sampler should be able to maintain the natural soil structure and amount of gas in the pores to a high degree, and should primarily be used in sandy and silty materials. The major challenge in the project was to achieve perfect sealing of the sample container after sample shearing. This was finally obtained by use of a ball valve and backpressurized ball-valve housing in the lower end of the sample container, and a piston in the upper end. The main problem with the ball-valve concept was wear and clogging from sand particles inside the ball valve, and various sampler designs were tested and evaluated before the final, robust design was chosen. The gas content in the soil is determined in situ, using backpressure for compression of the gas in the sample container, enabling deaired water to be injected in the sample. This water volume is recorded on a burette and is used to determine the total amount of gas in the sample. To obtain the degree of saturation Sr in the soil, the weight and volume of the soil grains is determined after dismantling of the sampler. Laboratory calibration tests show that a known gas volume of 100 mL may be measured with ±0.75 mL accuracy with the new sampler. The new sampler was used successfully at the LIMAS research site in Capbreton, France, where gas measurements were carried out under various wave and tidal conditions in a sandy seabed. The obtained results showed that the gas content could vary significantly in the upper 0.3–0.6 m top layer of the soil. The smallest gas contents, representing 0.2–0.65% of the sample volume, were measured under falling tide conditions after repeated cycles of strong waves. The tests showed that the new sampler can be used successfully under field conditions, provided that great care is taken during mounting and preparation of the equipment.]]></description>
      <pubDate>Tue, 30 Jan 2007 13:27:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/796169</guid>
    </item>
    <item>
      <title>Soil Variability Assessment with Fractal Techniques</title>
      <link>https://trid.trb.org/View/790233</link>
      <description><![CDATA[Understanding soil variability becomes imperative as the management tools become more sophisticated and soil uses become more multifaceted.  The importance of spatial and temporal variations in soil properties has long been recognized in soil knowledge and applying the knowledge in soil use.  Scientists and practitioners have come to the realization that the significance of soil variability needs to be quantified.  The statistics of soil properties have become essential components of soil descriptions.  A correct model of variability is necessary to interpret and use results of soil sampling.  Several models of the spatial variability have been proposed and are used to characterize soil structure and soil cover.  Fractal models have become popular in soil studies because they are designed to mimic and parameterize irregular objects that have similar features at different scales.  This similarity is common in soil matrix.  This chapter discusses the applicability of fractal models to spatial variations in soil properties.]]></description>
      <pubDate>Fri, 29 Sep 2006 10:37:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/790233</guid>
    </item>
    <item>
      <title>Geospatial Measurements of Apparent Soil Electrical Conductivity for Characterizing Soil Spatial Variability</title>
      <link>https://trid.trb.org/View/790237</link>
      <description><![CDATA[This chapter provides an overview of the characterization of soil spatial variability using EC(a) directed soil sampling for three different landscape-scale applications; (1) solute transport modeling in the vadose zone; (2) site-specific crop management; and (3) soil quality assessment.  Guidelines, methodology, strengths and limitations are presented for characterizing spatial and temporal variation in soil physiochemical properties using EC(a) directed soil sampling.]]></description>
      <pubDate>Fri, 29 Sep 2006 10:37:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/790237</guid>
    </item>
    <item>
      <title>Comparison of Methods for Determining Specific Surface Area of Soils</title>
      <link>https://trid.trb.org/View/786697</link>
      <description><![CDATA[The present study was undertaken to compare the capabilities of four of the known methods; more specifically, N subset 2 adsorption, methylene blue (MB)-titration, MB-spot test, and ethylene glycol monoethyl ether (EGME) methods were evaluated to determine the specific surface area (SSA) of 16 different clayey soils. The study showed that N subset 2 adsorption method underpredicts the SSA of soils, especially for smectitic soils. No significant differences were observed between N subset 2 SSA, MB SSA-titration, or MB-spot test for kaolinitic soils. The SSA estimates of MB-titration and MB-spot test methods were highly correlated for all soils. The EGME method has a very different procedure from the MB methods; however, it was highly correlated with MB methods (r squared 2=0.95). The N subset 2 adsorption method had no correlation to other methods. The cation exchange capacity of tested soils was highly correlated to the SSA, as high as r squared 2=0.77. No unique relationship was determined between the clay fraction and SSA.]]></description>
      <pubDate>Wed, 23 Aug 2006 07:58:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/786697</guid>
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