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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <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>Evaluation of Safety Operational Thresholds for Dynamic Compaction Techniques in Saturated Clayey Sands</title>
      <link>https://trid.trb.org/View/2690965</link>
      <description><![CDATA[The safety and operational thresholds of dynamic compaction techniques in loose clayey sand layers with high groundwater tables were investigated using stress-controlled cyclic triaxial tests. Simulations of intermittent and continuous loading patterns were conducted at confinement pressures of 32 kPa and 53 kPa. Results identified a critical threshold at a cyclic stress ratio greater than 0.35, where the soil transitioned from efficient densification to unstable dilation, accompanied by a spike in the excess pore-water pressure ratio above 0.30. Analysis of the stiffness degradation index established maximum effective cycle limits of 3–5 blows for high-energy intermittent loading and 30 blows for shallow continuous loading. Continuous loading induced significant shear strains at the higher confinement pressure of 53 kPa, dictating depth-dependent operational parameters. The findings supported an operational protocol integrating cumulative and impact-control strategies, analytically linked to the applied energy factor through a site-specific constant derived from geophysical testing.]]></description>
      <pubDate>Mon, 27 Apr 2026 14:58:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2690965</guid>
    </item>
    <item>
      <title>Numerical study on seismic dynamics of shallowly-buried immersed tunnel in sandy-clay seabed foundation</title>
      <link>https://trid.trb.org/View/2690567</link>
      <description><![CDATA[Immersed tunnels are critical components of urban transport infrastructure and are highly vulnerable to seismic activity in high-intensity zones. Understanding their dynamic response and potential failure modes is therefore essential for developing effective aseismic design criteria. This study employs the coupled numerical software FssiCAS, incorporating the PZIII and Soft Clay constitutive models, to systematically analyze the seismic behavior of an immersed tunnel embedded in a clay-over-sand marine stratum. The simulation successfully identified the potential failure mechanism induced by seismic loading. The results indicate that seismic waves cause significant pore pressure accumulation and a reduction in effective stress within seabed foundation. This triggers liquefaction in the underlying sand stratum. Interestingly, the liquefied layer acts as a seismic isolator, attenuating the upward propagation of horizontal shear waves, while simultaneously generating pronounced shear zones at the clay-sand interface. The tunnel undergoes notable vertical (buoyant) displacement, pronounced horizontal oscillation, and limited rotation. An analysis of differential displacements at the joints between adjacent tunnel segments reveals three primary instability modes. Collectively, these results demonstrate that the seismic response is governed by a complex soil-structure interaction, effectively captured by the FssiCAS platform, providing critical insights for the performance-based design of such infrastructures.]]></description>
      <pubDate>Mon, 27 Apr 2026 14:58:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2690567</guid>
    </item>
    <item>
      <title>Case History: Finite Element Analysis of Time Dependent Settlement of Lake Jessup Bridge Embankment in Central Florida</title>
      <link>https://trid.trb.org/View/2192012</link>
      <description><![CDATA[Finite Element Analysis (FEA) was performed to evaluate time dependent settlement of a three-stage approach embankment of Lake Jessup Bridge in Central Florida. The subsoil consisted of fine silty to clayey sands with interbedded shallow clays. FEA was performed utilizing Mohr-Coulomb and Soft Soil Creep models, which captured settlement and pore water pressure profiles during construction stages. The Soft Soil Creep model provided better predictions for the long term secondary settlement. Settlement plates were installed to monitor the in-field settlement during and after construction. The monitoring program continued for 8 months, at which, settlement rates substantially decreased. The recorded settlement-time profile was in general agreement with the settlement profile predicted using numerical analysis.]]></description>
      <pubDate>Mon, 23 Mar 2026 15:24:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2192012</guid>
    </item>
    <item>
      <title>Hybrid FEM-MLP Approach for Evaluating the Ultimate Load Capacity of Bored Piles in Sandy Clay Soil</title>
      <link>https://trid.trb.org/View/2668440</link>
      <description><![CDATA[This study developed a machine learning model based on a multi-layer feedforward neural network to predict the settlement and ultimate load capacity of bored piles using data from three-dimensional finite element simulations. A finite element model was established for sandy clay soil with elastic modulus ranging from 14,000 to 26,500 kN/m², internal friction angle from 28° to 34°, and cohesion from 3 to 6 kN/m². A bored pile with a diameter of 800 mm, a length of 43 m, an elastic modulus of 34.5 × 10⁶ kN/m², and a unit weight of 25 kN/m³ was analyzed under incremental static loading. The simulation results were used to train a neural network with three hidden layers (64–64–32 neurons) and a ReLU activation function. The model achieved high predictive accuracy, with R² = 0.9983, MAE = 6.60 mm, and RMSE = 11.43 mm, indicating effective representation of the nonlinear load–settlement relationship. The ultimate load capacity was estimated using piecewise linear regression, curvature-based analysis, and the slope ratio method, yielding values between 14,400 and 15,900 kN/m², with deviations of less than 10% compared to field static load test results. The results indicate that the proposed FEM–MLP framework can supplement finite element analyses.]]></description>
      <pubDate>Wed, 18 Feb 2026 12:00:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/2668440</guid>
    </item>
    <item>
      <title>Non-Isothermal Mechanical Response of Clayey Sands</title>
      <link>https://trid.trb.org/View/2636640</link>
      <description><![CDATA[The mechanical characteristics of clayey sands are crucial for evaluating behaviors pertinent to temperature-related geotechnical engineering. The undrained triaxial shear response of clayey sands, characterized by a constant skeleton void ratio, is experimentally investigated under varying fines contents, temperatures, and initial mean effective stresses. The effects of fines content and temperature on heating induced volumetric strain, peak deviatoric stress, peak excess pore pressure, stress ratio at the undrained instability state, and collapsibility index are comprehensively investigated. Furthermore, a unified critical state line is proposed in the equivalent intergranular void ratio versus mean effective stress plane for clean sands, sand-slit mixtures, and sand-clay mixtures, irrespective of temperature. Additionally, the equivalent intergranular state parameter can be utilized to predict the mechanical responses of binary mixtures under both undrained instability state and critical state. It is valuable to use the equivalent skeleton void ratio to assess the stability in thermally influenced geotechnical engineering involving binary mixtures, particularly sand-dominated mixtures.]]></description>
      <pubDate>Thu, 05 Feb 2026 09:16:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2636640</guid>
    </item>
    <item>
      <title>Internal instability evolution mechanism of tunnel face in sand-clay composite strata: Transparent soil model tests and DEM simulations</title>
      <link>https://trid.trb.org/View/2636281</link>
      <description><![CDATA[Tunnel face stability plays a decisive role in construction safety, particularly in sand-clay composite strata where the risks are significantly heightened. A thorough understanding of the instability evolution mechanism is therefore essential. Existing studies have not adequately revealed the internal instability evolution process under such composite strata conditions. In this study, accurately formulated transparent soil was employed in model tests at ambient temperature of 20 °C and constant humidity of 60 % RH, combined with discrete element method (DEM) simulations, to investigate the failure modes, evolution process, support pressure, and soil arching effect of tunnel face in sand-clay composite strata. The results demonstrate that the failure mode shows a basin-shaped global failure under shallow burial conditions, while a teardrop-shaped local failure under deep burial conditions. The soil arching effect restrains failure propagation toward the ground surface. Three critical ratios of tunnel face movement (s) to tunnel diameter (D) were identified at s/D = 3.0 %, 6.0 %, and 12.0 %, corresponding to initial instability, accelerated instability, and complete instability, respectively. The support pressure variation resembles that observed in pure clay, characterized by a rapid decline phase followed by a slow decline phase, with their intersection defining the limit support pressure. At the microscopic level, the deflection of principal stress direction dominates the soil arching effect. The arching zone in the composite strata spans approximately 0.94D. Furthermore, the soil arching effect intensifies as the stratum interface locates closer to the tunnel. The findings in this paper provide theoretical and practical insights into instability mechanisms and safety control for shield tunnelling in sand-clay composite strata.]]></description>
      <pubDate>Wed, 04 Feb 2026 16:28:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2636281</guid>
    </item>
    <item>
      <title>A Study on Soil Behavior and Safety in Dynamic Compaction of Clayey Sand with High Fines Content and High Groundwater Table</title>
      <link>https://trid.trb.org/View/2628347</link>
      <description><![CDATA[This study investigated the behavior of clayey sand with high fines content subjected to dynamic compaction using two methods: Finite Element Method (FEM) modeling and cyclic triaxial testing. Researchers developed an axisymmetric numerical model to simulate the dynamic compaction process and calculate acceleration values and Cyclic Stress Ratios (CSR) with distance from impact. The model was verified against field acceleration measurements, achieving an error margin of ± 20%. Cyclic triaxial tests, conducted under 32 kPa (2-m depth) and 53 kPa (4-m depth) confining stresses, subjected samples to CSR values ranging from 0.05 to 0.60. Laboratory tests revealed distinct, stress-dependent deformation patterns: lower confining stress samples exhibited continuous compressive strain (maximum shear strain of 0.65% at CSR = 0.60), while higher confining stress samples transitioned from compressive to dilative strain at values exceeding 0.40. Analysis of shear strain distribution indicated that strains approaching the critical threshold for soil degradation (≈ 5%) occurred in near-surface zones. This finding highlighted a significant operational safety concern regarding equipment placement near impact locations. The integrated approach provided a comprehensive understanding of soil deformation and informed safety considerations during ground improvement.]]></description>
      <pubDate>Wed, 26 Nov 2025 14:13:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2628347</guid>
    </item>
    <item>
      <title>Enhancing the Durability of Cement-Stabilized Clayey Sand with Zeolite and PVA Fibers Under Wet–Dry and Freeze–Thaw Cycles</title>
      <link>https://trid.trb.org/View/2563791</link>
      <description><![CDATA[In this study, the role of zeolite and polyvinyl alcohol (PVA) fibers on the durability of cement-stabilized clayey sand soil under freeze–thaw and wet–dry cycles was investigated. Laboratory tests, including unconfined compressive strength (UCS), scanning electron microscope (SEM), and ultrasonic pulse velocity (UPV), were performed to evaluate the effect of zeolite replacement ratio and fiber content on the durability and mechanical characteristics of the stabilized soil. The results showed that the mechanical properties of cemented samples decreased significantly under wet–dry cycles compared to freeze–thaw cycles. The optimal zeolite replacement ratio to achieve the most appropriate durability behavior of cement-treated clayey sand was 20%. Compared to the unreinforced samples, the samples with 0.8% fibers showed a lower reduction in UCS and mass loss under wet–dry and freeze–thaw cycles. The reduction in UCS was limited to 13% and 15%, respectively. The mass loss was limited to 5.2%, which indicates the positive effect of fibers in improving the durability of soil. Samples containing zeolite and fibers had lower mass loss in wet–dry and freeze–thaw conditions than samples without zeolite and fibers. Finally, the SEM microstructural observations justified the results of the durability tests.]]></description>
      <pubDate>Fri, 21 Nov 2025 08:44:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2563791</guid>
    </item>
    <item>
      <title>Leakage Characteristic Analysis and Hazard Level Classification of Gas Pipelines Considering Layered Soil Backfilling</title>
      <link>https://trid.trb.org/View/2547975</link>
      <description><![CDATA[Soil coverage is the essential difference between buried pipelines and above-ground pipelines. The soil environment affects the leakage and diffusion characteristics of gas. In this paper, the impact of various types of soil layering structures on the leakage and diffusion of natural gas in soil was studied by using numerical simulation. The horizontal hazard range (HHR), the vertical hazard range (VHR), and the surface hazard range (SHR) were defined, five levels of natural gas hazards were categorized, and the degree of accidental hazard under 15 conditions was analyzed by using the lower explosion limit of methane (5% vol.) as the hazardous boundary. The results showed that when the first layer of backfilled soil above the pipeline was clay, the other types and arrangement orders of layered soils had less of an effect on the diffusion of gas concentration. The three layers of soil were subject to greater clay resistance, reducing VHR and increasing HHR and SHR. After 3,600 s of leakage, the hazard level for sand, loam-sand, loam-clay-sand, clay-sand-loam, and clay-loam-sand all reached Level V. The research findings of this paper will provide a reference basis for the design of soil backfilling schemes in the construction of buried gas pipeline projects.]]></description>
      <pubDate>Wed, 24 Sep 2025 15:24:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2547975</guid>
    </item>
    <item>
      <title>XGBoost-Based Prediction of Bored Pile Settlement on Clayey Sand Using FEM-Based Data</title>
      <link>https://trid.trb.org/View/2571987</link>
      <description><![CDATA[This study aims to predict the vertical displacement (UZ) at the tip of bored piles using the XGBoost machine learning algorithm. The training data were generated from three-dimensional finite element simulations conducted with PLAXIS software. These simulations included various scenarios by altering key physical parameters of Clayey Sand soil, such as load, void ratio, elastic modulus, and other mechanical properties. The XGBoost model was trained on this dataset to accurately forecast pile settlement. Model performance was evaluated by comparing its predictions with field data obtained from static load tests. The results showed excellent agreement, with a coefficient of determination (R²) close to 0.99 and a root mean square error (RMSE) under 21 mm. These findings confirm the high predictive power of the model. More importantly, integrating FEM simulations with machine learning significantly reduces the need for repeated, time-consuming numerical analyses. This hybrid approach offers a fast, reliable, and cost-effective tool for designing bored pile foundations. Furthermore, the research demonstrates the potential of applying machine learning to solve complex geotechnical problems. It contributes to improving the efficiency and accuracy of foundation design in practical engineering.]]></description>
      <pubDate>Fri, 18 Jul 2025 09:05:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2571987</guid>
    </item>
    <item>
      <title>Ultimate Bearing Capacity of Bored Piles in Clayey Sand Determined Using Artificial Neural Networks</title>
      <link>https://trid.trb.org/View/2540037</link>
      <description><![CDATA[This study utilizes a combined approach of Finite Element Method (FEM) simulation and Artificial Neural Network (ANN) modeling to analyze and predict the load–displacement relationship of bored piles in clayey sand. FEM is applied to simulate the nonlinear relationship between load and vertical displacement, with input parameters including load and the mechanical properties of the soil. The results obtained from FEM are used as input data for the ANN model, enabling accurate predictions of vertical displacement based on these parameters. The findings of this study show that the predicted ultimate bearing capacity of the bored piles is highly accurate, with negligible error when compared to field experiments. The ANN model achieved a high level of accuracy, as reflected by an R² value of 0.9992, demonstrating the feasibility of applying machine learning in pile load analysis. This research provides a novel, efficient, and feasible approach for analyzing and predicting the bearing capacity of bored piles, while also paving the way for the application of machine learning in geotechnical engineering and foundation design. The integration of FEM and ANN not only minimizes errors compared to traditional methods but also significantly reduces time and costs when compared to field experiments.]]></description>
      <pubDate>Wed, 30 Apr 2025 16:57:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2540037</guid>
    </item>
    <item>
      <title>Integrating Multiple Linear Regression Analysis and Machine Learning Models to Predict the Bearing Capacity of Strip Footings on Sandy Clay Slopes</title>
      <link>https://trid.trb.org/View/2506134</link>
      <description><![CDATA[This paper presents Multiple Linear and Machine Learning models of bearing capacity for strip footings at sandy clay slopes subjected to vertical loads. Several parameters are considered in the analysis, including footing width, embedment depth, unit weight, slope angle, internal friction angle, and soil cohesion. A finite element analysis is conducted to assess the impact of these factors. Additionally, an empirical prediction for bearing capacity is proposed. Machine learning techniques utilising various models are employed to analyse performance outcomes, with the Shapley Additive Explanations (SHAP) method used to quantify the contribution of each parameter. The results show that the empirical formulation for predicting ultimate bearing capacity can be effectively applied in engineering practice. Significantly, the findings indicate that the XGBoost model yields the most precise predictions of bearing capacity. The primary parameters influencing bearing capacity include embedded depth, width, unit weight, and internal friction angle, whereas vertical load and unit weight have a minimal impact.]]></description>
      <pubDate>Thu, 27 Feb 2025 10:47:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2506134</guid>
    </item>
    <item>
      <title>The influence of alkali-activated slag for stabilisation and solidification of crude oil-polluted clayey sand for use in stabilised subgrade</title>
      <link>https://trid.trb.org/View/2487558</link>
      <description><![CDATA[This investigation examined the feasibility of employing oil-polluted soil solidified and stabilized with alkali-activated slag (AAS) in the subgrade of roads and railroads. A substantial quantity of granulated blast furnace slag (GBFS) is generated each year, resulting in significant environmental hazards due to its buildup and burying. Clayey sand (SC) was polluted with 3, 6, and 9% crude oil and stabilized with 2.5, 5, 10, and 15% slag activated with an alkaline solution. Besides compaction, unconfined compressive strength (UCS), California bearing ratio (CBR), and microstructural analysis, this study also evaluated the pollution concentration in the leachate of the cement structure of contaminated soil. The results demonstrated that AAS, via the formation of cementitious products and creation of a dense structure verified by microstructural analysis, increased the UCS and CBR of the oil-polluted SC soil by at least 2 and 5 times, respectively, and decreased its compressibility by at least 40%. The UPV test findings revealed that AAS causes the porosity to decrease much faster than the increase in compressive strength in the oil-contaminated soil (OCS). The concentration of oil pollution in the leachate showed that the AAS contributed greatly to reducing the transfer of oil pollution to the environment.]]></description>
      <pubDate>Wed, 29 Jan 2025 16:57:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2487558</guid>
    </item>
    <item>
      <title>Non-Destructive Testing of Reinforced Clayey Sand Stabilized with Seashell Ash Using Ultrasonic Pulse Velocity Test</title>
      <link>https://trid.trb.org/View/2449505</link>
      <description><![CDATA[This research uses seashell ash (SAA) and polyethylene terephthalate (PET) fibers to improve clayey sand soil. For this purpose, CBR and ultrasonic pulse velocity (UPV) tests are conducted on sandy soil samples with different clay contents and stabilized with different contents of SSA and PET fibers. Results indicated that the SSA and PET fiber inclusion caused an increase in CBR values, and it was found that the optimal mix design of the treated clayey sand is 30% clay, 7% SSA, and 1% PET fiber, and the optimum curing time was 28 days. The exponential relationship between UPV values (P-wave velocity or VP) and CBR test results showed that CBR could be predicted by UPV with acceptable accuracy.]]></description>
      <pubDate>Fri, 06 Dec 2024 09:19:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2449505</guid>
    </item>
    <item>
      <title>Strength Characteristics of Clayey Sand Stabilized Using Polypropylene Fiber or Portland Cement</title>
      <link>https://trid.trb.org/View/2386085</link>
      <description><![CDATA[The present study investigates the behavior of clayey sand soils stabilized using either polypropylene fiber or ordinary Portland cement. For this purpose, two homogeneous soil mixtures were prepared: (1) Soil A consists of 80% sand and 20% kaolin clay, and (2) Soil B consists of 60% sand and 40% kaolin. The prepared mixtures were reinforced by polypropylene fiber at target ratios of 0.1%, 0.25% and 0.4% by dry weight, or they were stabilized by Portland cement at target ratios of 1%, 2% and 3% by dry weight. A series of compaction tests, direct shear box tests and unconfined compression tests were performed in order to assess the effect of the individual inclusion of fiber or cement on the geotechnical characteristics of clayey sand. It was found that the shear strength of tested sand specimens was positively impacted by the addition of clay as long as the specimens were subjected to low normal stresses. Once the normal stress exceeded about 30 kN/m², the addition of clay had a detrimental impact on the shear strength. The inclusion of fibers or cement in the clayey sand developed a higher unconfined compressive strength (UCS). However, fibers provide a more ductile compressive performance up to high strains, whereas the cemented samples exhibit a sudden brittle failure. At the same cement (or fiber) content, clayey sand obtains higher values of UCS at higher clay contents.]]></description>
      <pubDate>Fri, 07 Jun 2024 10:13:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2386085</guid>
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