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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>
    </image>
    <item>
      <title>Probabilistic analysis of roadbed consolidation considering spatial variability of soft clay parameters</title>
      <link>https://trid.trb.org/View/2676299</link>
      <description><![CDATA[Due to the influence of depositional environments and groundwater conditions, soft clay often exhibits significant spatial variability in its soil parameters, rendering it highly susceptible to differential settlement. The combined vacuum and surcharge preloading method is widely used for soft clay reinforcement. However, most previous studies have concentrated on the spatial variability of parameters under the Mohr–Coulomb constitutive model, with limited attention given to the time-dependent reinforcement process. To assess the impact of parameter spatial uncertainty on foundation response, this study develops a three-dimensional stochastic finite element model based on the Modified Cam-Clay model. The model simulates the settlement evolution of clay and silty clay layers during combined vacuum and surcharge preloading and examines the influence of scale of fluctuation δ, as well as the coefficients of variation of the compression parameter λ and permeability coefficient k, on the settlement response. The results show that the variability of δ, λ, and k amplifies the dispersion of the settlement response. Among these factors, the vertical scale of fluctuation δz and the variability of λ exert a particularly pronounced effect on the mean settlement probability and final settlement, whereas k primarily affects the spread of the settlement process. Throughout the entire reinforcement process, the mean settlement value obtained through probabilistic analysis is close to that from deterministic analysis. Nevertheless, due to the substantial divergence and uncertainty of the probabilistic results, neglecting spatial variability may underestimate foundation settlement risks, leading to unsafe designs.]]></description>
      <pubDate>Wed, 17 Jun 2026 12:23:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2676299</guid>
    </item>
    <item>
      <title>Impact of Tamping on Repeated Ballast Settlement</title>
      <link>https://trid.trb.org/View/2675872</link>
      <description><![CDATA[It has been confirmed that track irregularity gradually returns to its original shape after ballast tamping on ballasted track even under the same track and support structure conditions. However, the details of this mechanism are not yet clear. Therefore, we surveyed an actual situation using track inspection data for this phenomenon. In addition, we performed tests with small-model, discontinuum analysis for ballast density after ballast tamping and cyclic loading tests, to reveal the mechanism of reversion in settlement after and before ballast tamping.]]></description>
      <pubDate>Fri, 05 Jun 2026 16:41:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/2675872</guid>
    </item>
    <item>
      <title>Effect of Natural Reinforcement Aperture Shape on Bearing Capacity of Reinforced Soil</title>
      <link>https://trid.trb.org/View/2113151</link>
      <description><![CDATA[It is of interest, for a developing country like India, to use natural and low-cost reinforcement material in rural roads. Bamboo is a locally and cheaply available alternative as a reinforcement material in place of commercial geosynthetic materials. The tridirectional bamboo grid is a new innovative reinforcement of the limited life geotextiles (LLGs) family. The present paper reports the experimental results of plate load tests conducted on sand overlying a soft clay. The model plate load tests were carried out to study the influence of the tridirectional and bidirectional bamboo grid with jute geotextile on the bearing capacity of soft marine clay. A mild steel tank with dimensions of 0.7 m × 0.7 m × 0.6 m and a square model footing size of 100 mm × 100 mm were used for all laboratory model tests. It was observed that by making a suitable modification in the aperture shape of reinforcement, the bearing capacity and settlement resistance of soft clay could be improved. The model test results show that the tridirectional bamboo grid offers superior performance compared to the bidirectional bamboo grid.]]></description>
      <pubDate>Thu, 28 May 2026 17:09:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2113151</guid>
    </item>
    <item>
      <title>Evaluation of Acoustic, Vibration, and Settlement Performance of Rigid Polyurethane–Recycled Rubber as Grouting Material for Subgrade Railway Ballast Substructure</title>
      <link>https://trid.trb.org/View/2703831</link>
      <description><![CDATA[Railway track ballast deterioration is frequently driven by substructure cracking, excessive vibration, and uneven settlement, which collectively compromise track geometry and operational safety. In geologically sensitive regions such as Southeast Malaysia, soil subgrades are particularly susceptible to these train-induced stresses. This study investigates the development of a sustainable injection grouting material, namely a polyurethane composite doped with fine recycled rubber powder (PUCR), to simultaneously enhance the mechanical, acoustic, and vibration-damping properties through an experimental approach. The composite formulations were rigorously evaluated using compressive strength testing, sound absorption coefficient and transmission loss, hammer-based vibration analysis, and one-dimensional oedometer consolidation tests. Experimental results identified the PUCR formulation containing 7.5% recycled rubber as optimal, providing a superior balance between structural integrity and energy dissipation. A sound absorption coefficient of PUCR demonstrates exceptional efficiency in mitigating high-frequency rolling noise in soil subgrade. Simulated PUCR injection in soil subgrades also reduced settlement, lowered natural frequencies, and improved consolidation behaviour, enhancing resistance to static loading. These findings demonstrate that PUCR is a high-performance and sustainable solution for railway infrastructure, offering dual benefits of substructure stabilization and noise reduction while advancing circular economy initiatives through the reuse of rubber waste.]]></description>
      <pubDate>Thu, 21 May 2026 09:10:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/2703831</guid>
    </item>
    <item>
      <title>Performance Analysis of Lime-Treated Geogrid-Reinforced Silty Sand for Rectangular Footings Using Experimental and Computational Approaches</title>
      <link>https://trid.trb.org/View/2703813</link>
      <description><![CDATA[This study assesses the combined effect of geogrid reinforcement and lime stabilization on the load-bearing and settlement characteristics of silty sand supporting a rectangular footing. A series of laboratory model load–settlement tests was conducted, incorporating variations in geogrid placement depth and lime content to evaluate the influence of these parameters on ultimate bearing capacity (UBC) and settlement behavior. To complement and extend these experimental findings, advanced computational approaches, random forest (RF), extreme gradient boosting (XGB), categorical boosting (CAT), and adaptive boosting (ADA), were employed to develop predictive models for UBC estimation. Model accuracy was assessed using widely accepted statistical indices, with results validated against experimental data to ensure reliability. Among the proposed algorithms, the CAT model achieved the highest predictive performance with training R² = 1.00 and testing R² = 0.951, followed by XGB, ADA, and RF models. From the results obtained, it can be concluded that the developed models effectively capture complex nonlinear interactions among soil properties, reinforcement parameters, and footing behavior. Integrating experiments with machine learning provides a faster, more cost-effective tool for geotechnical design, enabling optimized reinforcement use and efficient footing design.]]></description>
      <pubDate>Thu, 21 May 2026 09:10:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/2703813</guid>
    </item>
    <item>
      <title>Influence of Lagging Distance and Geometric Parameters on Surface Settlement in Mechanized Twin Tunneling</title>
      <link>https://trid.trb.org/View/2683010</link>
      <description><![CDATA[Twin-tunnel excavation in urban areas posed challenges for predicting surface settlement when excavation sequence, tunnel diameter, and center-to-center spacing interacted. Previous studies considered these parameters individually or used two-dimensional models, leaving their combined three-dimensional influence unresolved. Three-dimensional finite-element models were constructed using the Mohr–Coulomb constitutive law and validated against empirical superposition and independent benchmark cases (maximum deviation < 10%). Parametric analyses included tunnel diameters of 6.5–9.5 m, center-to-center spacing of 1.25D–3.8D, and lagging distances of 0–2 TBM lengths (9 m). Simultaneous excavation produced the highest surface settlement. Sequential excavation with a lagging distance of 2 TBM lengths reduced maximum settlement by up to 2.8-fold (64–71% lower) compared with simultaneous excavation. Increasing tunnel diameter from 6.5 m to 9.5 m amplified settlement by 28.6%, whereas increasing center-to-center spacing from 1.25D to 3.8D reduced settlement by 37.5%. Interaction effects became negligible beyond approximately 3D spacing. The results revealed the combined effects of construction sequencing, tunnel geometry, and soil behavior on longitudinal and transverse ground deformation, establishing quantitative relationships that enable safer, more predictable mechanized twin-tunnel excavation beneath sensitive urban infrastructure and guiding optimal design and construction practices for minimizing settlement.]]></description>
      <pubDate>Wed, 20 May 2026 09:10:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2683010</guid>
    </item>
    <item>
      <title>Evaluation of Causes of Excessive Settlements of Pavements Behind Bridge Abutments and Their Remedies: Phase II (Complete Report)</title>
      <link>https://trid.trb.org/View/2680632</link>
      <description><![CDATA[To evaluate the causes of bridge approach settlement a survey of 758 bridge approaches in seventy-seven counties of Oklahoma was conducted. In this survey, data related to the following items were collected: (i) bridge, abutment, approach, and slope protection structure; (ii) embankment material. Information related to the construction and maintenance for these approaches was collected by interviewing Oklahoma Department of Transportation (ODOT) personnel and searching records maintained at ODOT. The analyses of data show that the settlement problem is extensive in Oklahoma, namely, 83% of the approaches surveyed experienced settlement. It was observed that on the basis of long term performance rigid and flexible approaches are similar, but on a short term basis, rigid approaches experience lower differential settlement. Pile supported abutments as compared to stub type and high embankments with no drainage for the fills appear to be conducive to larger settlements. In general, skewed approaches have a higher settlement than non-skewed approaches. Regression techniques were used to develop an empirical relationship between the approach settlement and the causative parameters such as age of the approach, embankment height, traffic volume, and skewness of the approach. As a preliminary work for the next phase of the study, soil samples were collected from two sites. Comprehensive laboratory testing was conducted on these samples with the purpose of determining their site-specific embankment and foundation soil characteristics which may be used in a settlement prediction model.]]></description>
      <pubDate>Tue, 07 Apr 2026 10:08:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2680632</guid>
    </item>
    <item>
      <title>Evaluation of the Gilcrease Expressway Dynamic Compaction</title>
      <link>https://trid.trb.org/View/2680614</link>
      <description><![CDATA[This is the final evaluation report on the dynamic compaction project that was completed in 1985 on an abandoned strip mine and landfill. Since that time, the area has been monitored with instrumentation for lateral movement and horizontal settlement. Evaluation of the test data obtained from seven years of monitoring indicated no appreciable settlement of the embankment. The dynamic compaction of the abandoned strip mine and landfill appears to have worked effectively. The instrumentation that was used performed well and provided the necessary data to evaluate the dynamic compaction.]]></description>
      <pubDate>Sat, 04 Apr 2026 17:15:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2680614</guid>
    </item>
    <item>
      <title>Prediction of Time-Dependent Ground Settlement and Wall Deflection in Braced Excavations using an Enhanced Heteroskedastic Gaussian Distribution Regression Framework</title>
      <link>https://trid.trb.org/View/2680105</link>
      <description><![CDATA[The present study developed a probabilistic regression framework to predict maximum ground settlement and maximum wall deflection in deep braced excavations. A Heteroskedastic Gaussian Distribution Regression formulation was used to derive fitted predictive equations, allowing both the mean response and response variability to be modelled as functions of governing geotechnical parameters. The variance structure was explicitly linked to soil and excavation variables, thereby overcoming the deterministic nature of conventional machine learning approaches, which provided only point estimates without uncertainty representation. The framework enabled direct quantification of deformation uncertainty relevant to geotechnical risk assessment and excavation performance evaluation. Numerical analyses were conducted using advanced constitutive soil models capable of simulating elasto-plastic behaviour and time-dependent creep of soft clay deposits representative of eastern Indian conditions. A parametric investigation evaluated the effects of excavation rate and construction pause duration on settlement and wall deformation. Undrained, consolidation, and creep-induced settlements were separated through comparative numerical modelling. The predicted responses closely matched the simulated deformation trends. The regression model produced stable predictions with statistically interpretable uncertainty bounds, supporting probabilistic assessment of safety margins in braced excavation design and improving reliability in deformation-sensitive construction scenarios.]]></description>
      <pubDate>Wed, 25 Mar 2026 11:44:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2680105</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>Settlement Behavior of Compacted Oklahoma Soils</title>
      <link>https://trid.trb.org/View/2669626</link>
      <description><![CDATA[Numerous highway embankments experience post-construction settlement problems, such as bridge approach settlement that results in the "bump at the end of the bridge." One of the causes may be wetting-induced collapse settlement or simply, collapse settlement. Collapse settlement is a time-dependent process resulting from post-construction increases in moisture content. The post-construction settlement of numerous Oklahoma highway embankments raised questions as to whether the current Oklahoma Department of Transportation embankment specifications and construction practices are adequate in addressing collapse settlement, and prompted the current study to examine the influence of soil type on collapse potential of Oklahoma soils. One-dimensional oedometer tests were conducted to study the potential for collapse settlement of 22 Oklahoma soils and shales under conditions typically encountered in compacted fills. Results show that factors related to fine composition, such as clay-size fraction, plasticity index, liquid limit, activity, and AASHTO group index can be used for preliminary estimation of collapse index. Statistical analysis of the oedometer test data indicates that variables having the most impact on collapse index are moisture content, dry unit weight, plasticity index, and clay-size fraction. Settlement charts were developed to facilitate the estimation of collapse settlement of fills for different conditions, including fill height, moisture content, and soil type. Three scale centrifuge models compacted at different conditions and a case history of an embankment that has experienced significant collapse settlement are presented. Predictions based on one-dimensional oedometer-based method and settlement charts are compared to measured collapse settlements at the embankment centerlines. Given the uncertainty with field estimates of settlement, the comparison showed a reasonable agreement between predictions and field estimates of collapse settlement at the embankment centerlines; the limited evidence suggests that predictions based on one-dimensional assumptions tend to underestimate actual settlements possibly due to the two-dimensional nature of embankments. The review of literature regarding settlement of compacted fills, the laboratory test results obtained, and the field study of an actual embankment suggest the need for embankment design and specifications that will account for collapse susceptibility of different soil types. Specifications should demand for exceptional quality control and more stringent compaction requirements during embankment construction, particularly for large embankments, collapse-susceptible soils, and embankments susceptible to flooding.]]></description>
      <pubDate>Mon, 09 Mar 2026 16:50:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2669626</guid>
    </item>
    <item>
      <title>Experimental and theoretical study on the shield tunneling model for gas-bearing strata based on image processing</title>
      <link>https://trid.trb.org/View/2643918</link>
      <description><![CDATA[The free gas reservoirs occurring in the form of sacs are widely distributed along the southeastern coastal region of China, potentially posing significant risks during shield tunnelling. Hence, investigating the deformative mechanism of gas-bearing soils induced by shield excavation holds vital engineering significance. In this paper, physical model tests simulating gas-bearing strata were performed under varying L/D values (the ratio of the distance between shield excavation face and the sac to the tunnel diameter), with dry sand strata set as a control. The images captured during the tests were processed through PIV (Particle Image Velocimetry) analysis. It can be found that the variation regarding support pressure and pore pressure of fluid sac was primarily demarcated by the limiting state of the excavation, exhibiting two distinct phases in each test. Face instability occurred more rapidly in gas-bearing strata, the failure area evolved from an initial configuration of a “triangle and rectangle” to a final distribution resembling two interrelated trapezoids. The curves of surface settlement progressively exhibit a characteristic of groove shape as the displacement of tunnel face increased, and oblique photogrammetry technique was then adopted in this study to achieve three-dimensional reconstruction of the settlement pit. For a larger value of L/D, the influencing area induced by shield excavation varies within a broader range while the maximum deformation and volume is relatively small. By improving column hole shrinkage theory, a theoretical formulation accounting for soil loss was derived to accurately predict surface deformation in gas-bearing strata. On this basis, the effects of tunnel depth and excavation radius on surface deformation were analysed.]]></description>
      <pubDate>Thu, 26 Feb 2026 09:21:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643918</guid>
    </item>
    <item>
      <title>State of Practice for Specifying and Repairing Mechanically Stabilized Earth Walls</title>
      <link>https://trid.trb.org/View/2671985</link>
      <description><![CDATA[Wisconsin Department of Transportation (WisDOT) frequently uses Mechanically Stabilized Earth (MSE) walls due to cost-effectiveness and ability to tolerate movements during their service life. WisDOT has observed excessive deformation or wall-facing damage due to deterioration or vehicular impacts. Research into durability of MSE wall reinforcements and best practices to ensure their longevity would be beneficial. This research will evaluate allowable limits for MSE wall settlements and out-of-plane movements and investigate repair/remediation methods when those limits are exceeded, with or without signs of distress. The research will investigate repair solution to address compromised wall facings.]]></description>
      <pubDate>Wed, 18 Feb 2026 11:23:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2671985</guid>
    </item>
    <item>
      <title>Spatiotemporal-information-driven surrogate modeling for predictive analysis of shield tunneling-induced settlement</title>
      <link>https://trid.trb.org/View/2640820</link>
      <description><![CDATA[Ground settlement induced by shield tunneling is a critical concern in underground engineering, featuring complex spatiotemporal dependencies. To address the limitations of existing intelligent surrogate models in comprehensively considering influencing factors and achieving real-time prediction, this study proposes a deep learning-based settlement prediction framework that integrates multi-source information, including geometric features, multi-ring geological conditions, multi-time-step shield tunnelling parameters, and historical settlement records. Attention mechanisms are introduced to extract critical spatiotemporal dependencies, while a residual network is employed to map the fused representation to the predicted settlement. The proposed method is validated using two real tunnelling projects, demonstrating strong predictive performance with testing R² values of 0.92 and 0.97. Comparative experiments with traditional machine learning models and an LSTM-based variant further confirm the superiority of the attention-based architecture. Additionally, analysis of attention weights shows that the model can automatically focus on key operational moments and geologically sensitive strata, thereby enhancing interpretability and providing insights aligned with tunnelling process.]]></description>
      <pubDate>Tue, 17 Feb 2026 13:12:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2640820</guid>
    </item>
    <item>
      <title>Grouting and Ground Treatment: Case Studies in Applications of Grouting and Deep Mixing Use of Compaction Grout Columns to Stabilize Uncontrolled Loose Fill and to Lift a Settled Tunnel: A Significant Case History</title>
      <link>https://trid.trb.org/View/2200153</link>
      <description><![CDATA[Since the early 1960s, compaction-grouting techniques have been widely accepted as a means to density cohesionless soils and to lift settled structures. Compaction grouting techniques have been used less frequently in silts and cohesive soils, primarily due to the slow dissipation of pore water pressure. When used in silts and clay, careful monitoring of the water level is required. This paper documents the use of compaction grouting to density uncontrolled loose saturated fill and to lift a settled structure.]]></description>
      <pubDate>Fri, 06 Feb 2026 13:53:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2200153</guid>
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