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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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    <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>
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      <link>https://trid.trb.org/</link>
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      <title>Quantitative analysis of the mechanical behavior of granular sands subjected to particle pre-crushing</title>
      <link>https://trid.trb.org/View/2692410</link>
      <description><![CDATA[Particle crushing is a critical mechanism governing the macro-mechanical response of granular materials, yet current research predominantly focuses on thebehavior ofpristine sands, leaving a significant gap in understanding the quantitative effects of stress history. To address this, this study employs drained triaxial shearing tests coupled with high-performance Acoustic Emission (AE) monitoring to capture the multi-scale evolution of silica sands with varying degrees of pre-crushing. The results reveal that pre-crushing proportionally enhances peak shear strength and friction angle while suppressing particle re-crushing, volumetric contraction, andcrushing-induced high-frequency (>100 kHz) AE activities. By establishing quantitative characterization frameworks based on dissipated energy and high-frequency AE signatures, a fundamental transition in energy dissipation pathways from crushing-dominated to frictional rearrangement-dominated modes is deduced. This transition is attributed to the enhanced packing efficiency resulting from the combined influence of particle cushioning and a lower initial void ratio. Furthermore, a robust linear correlation between high-frequency AE hits and the breakage index is validated for both pristine and pre-crushed series.These findings highlight the feasibility of frequency-based AE analysis as a continuous, non-invasive tool for quantifying particle crushing under complex testing conditions.]]></description>
      <pubDate>Thu, 23 Jul 2026 09:14:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2692410</guid>
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    <item>
      <title>Temporal Evolution of Stormwater Basin Soil Properties and Infiltration Rates</title>
      <link>https://trid.trb.org/View/2566016</link>
      <description><![CDATA[Maintaining the soil infiltration capacity of stormwater infiltration practices is essential to long-term performance and resilience to changing land use and climate conditions. To date, however, the ability to predict how infiltration capacities change over time has been limited by a lack of understanding of how soil properties evolve with the age of the practice and the associated impacts on infiltration rates. To address this limitation, this study measured soil properties and infiltration rates in 28 stormwater infiltration basins ranging in age from 2 to 20 years. Soil organic matter, clay content, and silt content increased with age, while bulk density decreased with age, indicating both vegetation and soil biota activity and fine sediment accumulation contribute to soil profile evolution. Infiltration rates decreased with age, with a precipitous decline at approximately 12 years. Silt content was the best predictor of infiltration rate. However, age alone provided some predictive power, allowing infiltration practices to be prioritized for inspection and maintenance based on age. Visual indicators of basin failure included the presence of hydric soils, ponding, sediment accumulation, impaired vegetation, and presence of wetland vegetation. Therefore, a combination of age, visual inspection, and measurement of soil properties and infiltration rates is recommended to identify practices for rehabilitation. Inspection at 5-year intervals is recommended and is consistent with the requirements of the Minnesota Department of Transportation (MnDOT) MS4 permit.]]></description>
      <pubDate>Wed, 16 Jul 2025 09:51:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2566016</guid>
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    <item>
      <title>Discrete Element Method Study of Micro–Macro Mechanical Behavior of Unsaturated Granular Soils</title>
      <link>https://trid.trb.org/View/2516442</link>
      <description><![CDATA[This study investigated contact distribution and force anisotropy associated with elliptical particles in granular soils within the pendular state of unsaturated soils, employing the discrete element method. The high cost of determining the micromechanical factors through laboratory tests justifies the use of this method. The macromechanical behavior of unsaturated granular soils depends on interparticle contact characteristics and liquid bridge behavior. The findings indicated that as the degree of saturation increased, both the shear strength and the anisotropy of the normal and shear forces initially rose before subsequently declining. Notably, the contact normal anisotropy exhibited minimal variation with changes in saturation. Furthermore, it was observed that as confining pressure increased at a specific eccentricity and degree of saturation, the associated anisotropies exhibited a continuous increase. In this context, as the eccentricity of the particles increased, the peak shear strength and its corresponding anisotropies initially increased and then decreased. Conversely, residual soil strength showed a consistent increase in shear strength and anisotropy with rising eccentricity.Graphical Abstract]]></description>
      <pubDate>Tue, 27 May 2025 09:33:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2516442</guid>
    </item>
    <item>
      <title>Incorporating the Site Variability and Laboratory/ In-situ Testing Variability of Soil Properties in Geotechnical Engineering Design</title>
      <link>https://trid.trb.org/View/2255653</link>
      <description><![CDATA[The properties of geomaterials usually vary from one location to another within the same site, in both the vertical and horizontal directions. The variability of soil properties is a complex phenomenon that results from several sources of uncertainties, including inherited spatial variability, measurement error, statistical error, and model bias error. This study aimed at investigating the different methods and techniques used to evaluate the spatial variability of soil properties; the different sources of geotechnical variability; quantifying the variability of soil properties for inclusion in analysis; and design of different geotechnical engineering applications. This included conducting in-box tests and field tests on constructed sections at the Accelerated Load Facility (ALF) site and under-construction sections from different projects using different devices, such as Dynamic Cone Penetrometer (DCP), Light Falling Weight Deflectometer (LFWD), and Geogauge. Typical laboratory tests, such as Atterberg limits, unconsolidated undrained (UU) triaxial, small direct shear, consolidation, and California bearing ratio (CBR) tests, were also conducted to evaluate the specimen and operator-related variability of different soil properties. In addition, the specific site variability was also evaluated using the results from soil borings with laboratory tests and/or the results of in-situ tests such as cone penetration test (CPT) and standard penetration tests (SPT).]]></description>
      <pubDate>Thu, 28 Sep 2023 09:16:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2255653</guid>
    </item>
    <item>
      <title>Effect of spatial variability of soil properties and geostatistical conditional simulation on reliability characteristics and critical slip surfaces of soil slopes</title>
      <link>https://trid.trb.org/View/2100429</link>
      <description><![CDATA[Evaluation of the stability and determination of the Critical Slip Surface (CSS) of soil slopes are salient topics in geotechnical engineering. On the other hand, the stability and CSS are not only affected by soil heterogeneity but also by the boreholes’ location and method of predicting soil parameters in the domain of analysis. The unconditional simulation in which known data and its location are not incorporated may lead to results far from reality. Moreover, in some conditional simulations, the borehole data are directly mapped into the analysis section without taking the location of the known data into account, which can either overestimate or underestimate the stability of the slope. In the current study, the Finite Element Method (FEM) is coupled with the geostatistical method to evaluate the reliability characteristics and CSS distribution with consideration of the known data, location of boreholes, uncertainty of surcharge load, and soil heterogeneity. The results of a real case demonstrate that in comparison to the unconditional simulation, utilizing the conditional simulation improves the distribution of Factor of Safety (FS) by up to 14% while decreasing the related standard deviation by 4% to 40%. Moreover, conditional simulation offers a significant reduction in uncertainty of the slip surface and unsafe distance from the edge of the slope. Besides, it is concluded that soil heterogeneity has a major impact on CSS distribution and induces the local CSS, which cannot occur on a homogeneous slope.]]></description>
      <pubDate>Wed, 22 Feb 2023 09:57:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2100429</guid>
    </item>
    <item>
      <title>Grain-Size Distribution Effects on the Mechanical Behavior of Granular Soil in Response to EPBS Tunneling</title>
      <link>https://trid.trb.org/View/2030276</link>
      <description><![CDATA[A set of model tests using a miniature Earth Pressure Balanced Shield (EPBS) machine are carried out to examine the effects of grain-size distribution on the mechanical behavior of granular soil in response to EPBS tunneling. The combined effects of particle size (D₅₀) and tunnel depth on the vertical movement and volume loss of ground are studied. A discussion of the implications of the soil arching effect and volumetric strain associated with D₅₀ to the results is also provided. The results show that the deformation patterns of ground are highly dependent on the grain-size distribution of the soil, especially for relatively deep tunnels. The value of trough width parameter (k) for fine soil exhibits an obvious nonlinear increase with the depth. However, it is linear for the soil with a relative large grain size. The particle size has a significant influence on the variation of soil volume loss at the surface level, especially for relatively deep tunnels.]]></description>
      <pubDate>Mon, 28 Nov 2022 09:17:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2030276</guid>
    </item>
    <item>
      <title>Effect of Soluble Salts on Mechanical Properties of Granular Subgrade for Road Pavements</title>
      <link>https://trid.trb.org/View/2022976</link>
      <description><![CDATA[The existence of soluble salts in granular materials of highway pavements has become a widely spread problem in Iraq. This research is performed to evaluate the influence of soluble salts on the engineering properties of a soil-aggregate material brought out from a road fill of a newly constructed rural road in Samawah city, south of Iraq. Soluble salts, represented by sodium chloride (NaCl), sodium sulphate (Na₂SO₄) and gypsum (CaSO₄·2H₂O), were added to the granular material by different percentages ranging from zero to 15% by weight of the dry soil. The influence of soluble salts on the maximum dry density, performed using the modified proctor compaction test, was obtained and plotted. The effect of soluble salts on the resilient modulus was investigated. Consolidated undrained triaxial results indicate that soluble salts may not adversely affect the main component of shear strength of the granular material. However, findings obtained using California Bearing Ratio (CBR) test show that the existence of soluble salts in the granular material can significantly reduce the CBR value, especially when the soaking period exceeds 15 days. The physical effect of soluble salts depends mainly on their solubility and rate of dissolution in addition to the amount of water that exists.]]></description>
      <pubDate>Fri, 23 Sep 2022 13:13:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2022976</guid>
    </item>
    <item>
      <title>Critique of CANDE/AASHTO Soil Groups</title>
      <link>https://trid.trb.org/View/1869277</link>
      <description><![CDATA[CANDE and AASHTO pipe design documents inappropriately group soil types that have greatly varying strength and compressibility properties leading to unnecessary design uncertainty. Most notably, fine-grained elastic silt (MH) is grouped with coarse-grained clayey gravel (GC). There are other groupings that also do not seem appropriate. A defensible design of buried pipe requires acceptable limits on uncertainty. The CANDE and AASHTO groups exhibit an unjustifiably broad range of soil behavior and therefore may often not result in designs of acceptable uncertainty. Additionally, the CANDE and AASHTO naming convention causes problems in referring to the soil groups by using redundant symbols. The inappropriate grouping of some of the soil classifications will be illustrated by comparing their engineering properties. An alternate grouping is proposed.]]></description>
      <pubDate>Mon, 30 Aug 2021 14:50:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1869277</guid>
    </item>
    <item>
      <title>Development of Prediction Models for Resilient Modulus of Soils</title>
      <link>https://trid.trb.org/View/1846519</link>
      <description><![CDATA[Proper structural design of pavement systems requires knowing the resilient modulus of the soil, as this parameter is a proven predictor of the stress-dependent elastic modulus of soil materials under traffic loading. One of the common methods for estimating resilient modulus, in lieu of laboratory testing, involves using verified prediction models that are based on a soil’s basic index properties. These models can save considerable laboratory testing time and cost for the repeated load triaxial testing process. However, similar regression models developed for different soils may not represent the behavior of regional soils, especially given the typically limited number of soil specimens systematically studied for development of the models. A multiple regression analysis and stepwise regression analysis were performed to correlate the experimentally measured resilient modulus values with the fundamental soil properties (such as standard Proctor test, sieve analysis, hydrometer testing, and Atterberg limits). The regression models for a specific AASHTO soil type for Colorado were shown in this study to provide superior performance over the existing published models. The use of these developed prediction models can be expected to save a considerable amount of time and money in testing and analyzing soil properties.]]></description>
      <pubDate>Fri, 23 Apr 2021 15:14:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1846519</guid>
    </item>
    <item>
      <title>Geo-Congress 2020: Modeling, Geomaterials, and Site Characterization</title>
      <link>https://trid.trb.org/View/1693048</link>
      <description><![CDATA[This Geotechnical Special Publication contains 68 peer-reviewed papers on modeling, geomaterials, and site characterization. The papers are selected from sessions of Geo-Congress 2020, held in Minneapolis, Minnesota in February 2020. Topics include: computational geotechnics; soil properties and modeling; geophysical engineering; advances in geomechanics; and engineering geology and site characterization. GSP 317 will be useful to researchers and practitioners in all areas of geotechnical site characterization.]]></description>
      <pubDate>Wed, 08 Apr 2020 08:52:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1693048</guid>
    </item>
    <item>
      <title>A Study of Tensile Stress with Suction by Restrained Ring Method</title>
      <link>https://trid.trb.org/View/1671512</link>
      <description><![CDATA[In expansive soils, tensile strength and tensile stress are two main factors that control the development of cracks due to drying shrinkage. Numerous experimental methods and theoretical models have been proposed for the measurement and prediction of tensile strength. However, there are only few studies that focus on the measurement and prediction of tensile stresses in expansive soils. Understanding the mechanism behind the crack initiation due to an increase in suction in expansive soils is of paramount importance in geotechnical engineering. In this study, the restrained ring method was modified for studying the variation of tensile stress with suction. Strain gauges were installed in the restrained ring to measure tensile strain, and a tensiometer and filter paper method were utilized to measure the suction. The experimental test results indicate that the change of tensile tress with suction can be generally simulated by the model proposed by Chen and Bulut [10]. It is noted that tensile stress increases nearly linearly with suction expressed in the unit of pF (i.e., in logarithmic scale, pF=log (10kPa)). In addition, it is found that the maximum tensile stress measured from the specimens initially at optimum water content is approximately twice the value of the maximum tensile stress measured from the specimens at near-saturation state. The test results also indicate that the suction change from the initial moisture state to crack initiation is about 0.2–0.3pF for the specimens at optimum water content, and is about 0.5–0.7 pF for the specimens at near-saturation moisture state.]]></description>
      <pubDate>Wed, 29 Jan 2020 14:59:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/1671512</guid>
    </item>
    <item>
      <title>Study of a Natural Unsaturated Clay and Its Effect on Railroads</title>
      <link>https://trid.trb.org/View/1559887</link>
      <description><![CDATA[Subgrades and embankments of railroads on unsaturated clay are subjected to not only climatic variation (and its corresponding volume change), but also to increasing dynamic train loading. Shrink/swell soils are known to exacerbate railroad track conditions. In this study, field investigation, laboratory tests, and numerical modeling are integrated to advance current understanding the impact of shrink/swell soil on railroad behavior. A test site in Texas at an actual union pacific (UP) railroad section was selected to study in detail the interactions between railroad dynamic loading, natural (shrink/swell) foundation soils, local topographic conditions (controlling the drainage), and climatic variations. A comprehensive set of ongoing laboratory tests are being conducted to investigate hydraulic, volumetric, and dynamic soil properties. The ongoing study examined soil hydro-mechanical and dynamic properties and the results obtained from the laboratory tests are to be used in numerical modeling which can help in extrapolating the behavior of railroad on shrink/swell soils in various scenarios. Using the aforementioned (field, laboratory, and numerical) methodologies, the actual behavior of railroad under different weather conditions and dynamic loading is studied; the mechanism of railroad deformation due to train loading and weather change is examined; and dynamic numerical models are validated for simulations of future study.]]></description>
      <pubDate>Tue, 16 Oct 2018 09:40:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/1559887</guid>
    </item>
    <item>
      <title>Spatial Delineation of Corrosion Zones for Metal Culverts Based on Coastal Louisiana Soil Characteristics</title>
      <link>https://trid.trb.org/View/1495804</link>
      <description><![CDATA[Corrosion of metal pipes used as culverts is a problem that affect many agencies directly involved in designing and maintaining these culverts. The corrosive environment of soil types found in a region could vary in a significant way (mildly corrosive to extremely corrosive) based on soil characteristics. Environmental conditions such as high water table, acidity and presence of various salts could make a soil corrosive to metal pipes. In this article, authors have applied a methodology of processing readily available soil data such as spatial distribution of soil types and soil characteristics (e.g. pH and conductivity) in delineating spatial corrosion zones in Coastal Louisiana. A combination of data, obtained from field surveys provided by the Louisiana Department of Transportation & Development and the Web Soil Survey Data provided by Natural Resources Conservation Service, were used to create an interpolated surface representing zones corrosive to metal culverts. The corrosion zones are classified based on expected service life spans of these culverts. The soil characteristics were incorporated in to previously established corrosion models to assess expected service life of metal culverts. Results suggest that about 80% area of the Coastal Louisiana is either highly corrosive or extremely corrosive resulting in expected service life of metal culverts 40 years or less.]]></description>
      <pubDate>Wed, 07 Feb 2018 13:41:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1495804</guid>
    </item>
    <item>
      <title>Suffusion Patterns for Granular Soils: Observations from Numerical Simulations</title>
      <link>https://trid.trb.org/View/1438519</link>
      <description><![CDATA[Fine particles migrate through voids of coarse fabrics by seepage force in a process called suffusion. A coarse soil structure resulting from fines loss will lead to changes in hydraulic and mechanical properties, including increased permeability, decreased strength and decreased stability that will bring significant settlement or failure of the levees, embankments and dams. This paper presents a coupled computational fluid dynamics and discrete element method (CFD-DEM) approach to model the suffusion process. Suffusion erosion is activated by maintaining a constant hydraulic gradient across the soil samples. The concept of a transition layer is used to explain the process and patterns of suffusion. The effects of particle size distribution, seepage velocity, fines content and initial void ratio on the transition layer in suffusion are investigated. In addition, four commonly used internal stability assessment criteria were compared with micromechanical properties of the particles.]]></description>
      <pubDate>Tue, 07 Mar 2017 10:25:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1438519</guid>
    </item>
    <item>
      <title>Development of Next Generation Liquefaction (NGL) Database for Liquefaction-Induced Lateral Spread</title>
      <link>https://trid.trb.org/View/1435355</link>
      <description><![CDATA[The primary outcome of this research is a vetted and community database of seismic, topographical, geotechnical and horizontal displacement measurements pertaining to case histories of liquefaction-induced lateral spread for further research and model development by other researchers and investigators under the auspices of the Pacific Earthquake Engineering Research (PEER) Center (http://peer.berkeley.edu/). Secondary outcomes will be web host and publishing required to house and disseminate this database and its supporting information.  This project has the following research objectives: (1) develop peer-reviewed and consistent methodology for data documentation and archiving of lateral spread case histories, (2) develop quality assurance protocols for assessing and documenting data quality, (3) develop methods and/or protocols to quantify uncertainties associated with the collected data, (4) populate the case history database with well-documented examples of liquefaction-induced lateral spread, (5) review screening criterion used in evaluating lateral spread potential, (6) disseminate the database for general use using web-based software tools.]]></description>
      <pubDate>Tue, 22 Nov 2016 07:07:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1435355</guid>
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