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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=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7RGVmb3JtYXRpb24mcXVvdDsiIG9yaWdpbmFsX3ZhbHVlPSImcXVvdDtEZWZvcm1hdGlvbiZxdW90OyIgLz48L2ZpbHRlcnM+PHJhbmdlcyAvPjxzb3J0cz48c29ydCBmaWVsZD0icHVibGlzaGVkIiBvcmRlcj0iZGVzYyIgLz48L3NvcnRzPjxwZXJzaXN0cz48cGVyc2lzdCBuYW1lPSJyYW5nZXR5cGUiIHZhbHVlPSJwdWJsaXNoZWRkYXRlIiAvPjwvcGVyc2lzdHM+PC9zZWFyY2g+" 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>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Analysis and characterization of track vertical deviation in kilometer-level span high-speed railway bridge</title>
      <link>https://trid.trb.org/View/2736449</link>
      <description><![CDATA[During the operation, the measured track vertical deviation of the kilometre-level span railway bridge would include complex bridge deformations due to thermal loads and construction deviations, making it difficult to separate the track irregularity and the complex bridge deformation. Further studies are still required to evaluate the track geometry and formulate the maintenance reference alignment. This study proposed that the measured track vertical deviation is composed of theoretical temperature deformation, constant construction deviation, complex additional deformation and fitted track irregularity. A corresponding analysis method is established: A parameter optimization model incorporating structure temperature differences is constructed to obtain the theoretical temperature deformation. PowerICA is employed to precisely extract complex additional deformation and constant construction deviation. After characterizing the three components, a bridge deformation fitting model is constructed, and the fitted track irregularity is defined as the difference between the measured data and the fitted deformation. Through the engineering case of a kilometre level suspension bridge, it was verified that compared with the deformations based on ambient temperatures, the fitted deformation has significant improvements in RMSE and determination coefficient (R²). The proposed fitted track irregularity and the filtered measured deviation are processed with the mid-point chord measurement of 10 m, 30 m and 60 m, respectively. The results of the two are highly consistent, with a correlation coefficient consistently above 0.95. The method can accurately characterize the deformation patterns under complex conditions and provide a scientific basis for the formulation of the maintenance reference alignment.]]></description>
      <pubDate>Mon, 12 Oct 2026 08:34:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2736449</guid>
    </item>
    <item>
      <title>Experimental and numerical evaluation of a height-adjustable short-sleeper ballastless track system for subgrade deformation accommodation</title>
      <link>https://trid.trb.org/View/2736448</link>
      <description><![CDATA[ Conventional ballastless track deformation solutions, like fastening adjustments and slab lifting, have limited adaptability and stability under severe subgrade deformation. This study validates a Height-Adjustable Ballastless Track with Short Sleepers (HBTS) using finite element modeling and experimental testing. The model, verified for displacement and strain, assesses structural strength under various loads. Results show consistent stiffness, displacement, and strain, with stresses below design limits. Post-adjustment changes in axial force, shear, and bending moment are minimal. Peak sleeper displacement at expansion joints is 0.226 mm, and the track maintains concrete stress limits. Vertical bearing capacity decreases by 1.87% post-adjustment, while longitudinal capacity remains nearly unchanged. HBTS ensures efficient height adjustment and structural stability.]]></description>
      <pubDate>Mon, 12 Oct 2026 08:34:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2736448</guid>
    </item>
    <item>
      <title>Dynamic response of high-speed trains under uneven temperature fields of slab tracks on cable-stayed bridges</title>
      <link>https://trid.trb.org/View/2772342</link>
      <description><![CDATA[The temperature deformation of a long-span cable-stayed bridge (LSCSB) could significantly deteriorate the smoothness of rails, thereby affecting the dynamic behavior of high-speed trains (HSTs). In this paper, based on the thermal-fluid-structure coupling theory and vehicle-track coupling dynamics theory, an analysis method was proposed to explore the influence of temperature deformation of LSCSBs on the dynamic behavior of HSTs. The temperature deformation of LSCSBs within a day was analyzed, and the dynamic behavior of HSTs passing through the LSCSBs at different times was revealed. The results showed that on a summer day, the temperature deformation of LSCSBs varied significantly and rapidly, and the variation experienced a significant increase of 23.46% within just 2 h. Due to the influence of structural temperature deformation, the wheel-rail interaction, train safety, and passenger comfort changed noticeably. The construction temperature of the bridge and track decisively affected the dynamic behavior of the train. Therefore, it was crucial to construct the structure under suitable temperature conditions to prevent further exacerbation of the dynamic behavior of HSTs due to violent temperature differentials. In summary, the method proposed in this paper could contribute to a comprehensive and in-depth understanding of the operational characteristics of HSTs on LSCSBs.]]></description>
      <pubDate>Thu, 08 Oct 2026 17:03:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2772342</guid>
    </item>
    <item>
      <title>Geometrical morphology and deformation measurement of long-span suspension bridge based on terrestrial laser scanning</title>
      <link>https://trid.trb.org/View/2772341</link>
      <description><![CDATA[Long-span suspension bridges necessitate deformation measurements for proper evaluation and upkeep. However, conventional approaches are unable to collect continuous spatial deformation data, which severely restricts their application in structural research. This paper presents a reliable and efficient method for measuring the deformation of suspension bridges using 3D laser scanning, including planning the scanning route, preprocessing the point cloud data, and extracting the deformation indicators. The method plans the scanning route based on experience and basic path planning principles to achieve both efficiency and precision, preprocesses the point cloud data by 3-stage denoising and curvature-based downsampling to preserve valuable point data better, and then proposes an extraction procedure for different types of deformation indicators. A field test on a typical long-span suspension highway bridge is performed, and the data processing and results extraction details are introduced. The accuracy and consistency of measurement results are discussed to verify the reliability of the proposed approach. The verified data provides useful information for the evaluation and maintenance of the bridge.]]></description>
      <pubDate>Thu, 08 Oct 2026 17:03:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2772341</guid>
    </item>
    <item>
      <title>Field measurement and numerical simulation on vertical temperature gradient of steel box girders</title>
      <link>https://trid.trb.org/View/2772340</link>
      <description><![CDATA[The vertical temperature gradient (VTG) is a critical factor contributing to thermal stresses or deformations in bridge structures. However, the current provisions concerning the VTG of steel box girders are inadequate. Accordingly, this paper systematically investigated the VTG of a steel box girder in Wuhan using field measurement and numerical simulations. The temperature distributions of the steel box girder were first characterised based on measured temperature data. A thermal model of the steel box girder was then established using measured time-varying meteorological data, with the convective heat transfer coefficient obtained through an inversion method to update the model. The numerical findings align well with the observed temperature, and the fitted unfavourable VTG values exceed the current normative threshold. Furthermore, parametric investigations were carried out to reveal the impacts of meteorological and structural parameters on the VTG. The results indicate that solar radiation and pavement thickness have a considerable impact on the VTG. Finally, this research recommends that the present VTG guidelines should be modified by introducing appropriate adjustment factors related to the level of solar radiation intensity in different regions to strengthen their capacity for safeguarding.]]></description>
      <pubDate>Thu, 08 Oct 2026 17:03:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2772340</guid>
    </item>
    <item>
      <title>Large-deformation theoretical analysis of open-end thick-walled tubes under internal pressure</title>
      <link>https://trid.trb.org/View/2785955</link>
      <description><![CDATA[Subsea pipelines and deepwater risers are critical components in offshore oil and gas production, often subjected to extreme internal pressure during operation and hydrotesting. This study proposes a rigorous theoretical model for stress-strain analysis on open-end thick-walled cylinders subjected to uniform internal pressure within a large deformation framework. By combining specific constitutive relations, compatibility and equilibrium equations, a numerical solution is developed and systematically validated against classical small-deformation analytical methods as well as linear and nonlinear finite element models. The proposed large-strain formulation shows excellent agreement with small-strain analytical results under small deformation conditions, confirming mutual validity in the small-strain regime. However, as the tube experiences post-yield expansion, the small-deformation solution exhibits significant deviations due to the unaccounted geometric nonlinearities, whereas the large-strain approach maintains high accuracy. This work extends large-deformation analysis to open-end boundary conditions, providing a validated analysis method for the design and integrity assessment of pipelines and other pressure-containing structures in scenarios involving substantial post-yield expansion of hollow cylinders.]]></description>
      <pubDate>Tue, 06 Oct 2026 15:52:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2785955</guid>
    </item>
    <item>
      <title>A novel method for accurate prediction of marine propulsion shaft alignment performance considering the elastic deformation of an air-spring-supported floating raft</title>
      <link>https://trid.trb.org/View/2782473</link>
      <description><![CDATA[Accurate prediction of propulsion-system alignment is essential for reducing ship vibration and noise and improving system reliability and service performance. However, for floating raft–propulsion shafting systems supported by air springs, strong nonlinear deformation and complex boundary-transfer effects make accurate alignment prediction difficult. To address this issue, this paper proposes an accurate static deformation calculation method, termed ARSCM, for elastically supported floating raft–propulsion shafting coupled systems. First, the displacement field of the floating raft is constructed using the Rayleigh–Ritz method, in which an air-spring preload term is introduced into the potential energy functional and local rigid-body displacement compatibility constraints are imposed through an augmented system of equations, enabling refined modeling under complex boundary conditions. Second, the propulsion shafting is equivalently modeled as a multi-segment Winkler beam with uncertain contact states. Within a unified energy variational framework, contact constraint energy terms are incorporated, and a Sigmoid-like activation function is adopted to smoothly describe the nonlinear shaft–bearing contact behavior, thereby ensuring stable solutions for shaft deformation. Third, to account for the strong coupling between the floating raft and the shafting, an Aitken Δ2 adaptive relaxation strategy is introduced to achieve efficient and robust iterative solutions of the coupled nonlinear equations. Finally, comparisons with ANSYS simulations and experimental results demonstrate that the proposed method significantly improves computational efficiency while maintaining high prediction accuracy. The proposed ARSCM provides an efficient and physically interpretable tool for propulsion shaft alignment analysis and performance improvement.]]></description>
      <pubDate>Thu, 01 Oct 2026 11:44:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2782473</guid>
    </item>
    <item>
      <title>Comparative Analysis of Two Kinds of Support Structure in Jointed Rock Tunnels: Rock Bolts and Steel Arches</title>
      <link>https://trid.trb.org/View/2784658</link>
      <description><![CDATA[Rock bolts and steel arches are common methods of support used in tunnel engineering. To compare the support efficiency of rock bolts and steel arches, numerical simulations were conducted using discrete element software to analyze the mechanical response characteristics and tunnel stability of support systems. Firstly, the supporting effects of rock bolt and steel arch supports were studied, taking into consideration the different buried depths of the tunnels. The combined effect of rock bolt and steel arch supports under different parameters was also studied. The results show that, at a burial depth of 17 m, both support methods have similar surrounding rock deformation reduction ratios. When the depth is less than 17 m, steel arch support reduces deformation better than rock bolts; when it exceeds 17 m, rock bolts outperform steel arches. In addition, the prestress value and length of rock bolts were shown to be negatively correlated with surrounding rock deformation. As the prestress value rose, roof settlement decreased by 46% and stayed constant when it exceeded 120 kN. As the bolt length increased, roof settlement decreased by 39% and remained unchanged after reaching 3.5 m. In joint model tests, the prestressed rock bolt was found to inhibit the deformation and failure of the surrounding rock. The optimized support parameters were applied to the engineering field, and field verification revealed that the settlement of the tunnel vault was stable at 4.8 mm after 40 days, which effectively controls the deformation of the tunnel. The research results provide a reference for the selection and design of surrounding rock support methods for tunnels.]]></description>
      <pubDate>Thu, 01 Oct 2026 09:27:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2784658</guid>
    </item>
    <item>
      <title>Fractal-wavelet diagnostics of liquefaction-induced transport corridor deformation after the 6 February 2023 Kahramanmaraş earthquakes: Evidence from the Hatay airport access road</title>
      <link>https://trid.trb.org/View/2732955</link>
      <description><![CDATA[The 6 February 2023 earthquakes in Türkiye inflicted widespread damage on transportation infrastructure, resulting in complex, spatially heterogeneous deformation patterns, most notably along the Hatay Airport access road. Situated atop the alluvial deposits of the former Amik Lake basin, this roadway is inherently susceptible to liquefaction-induced settlement and ground instability. This study examines the underlying damage mechanisms affecting this strategically important corridor using advanced signal-processing methodologies that go beyond conventional analytical techniques. High-precision post-event GNSS measurements were employed to characterize the post-earthquake roadway surface profile and its spatial irregularity structure. The statistical characteristics and persistence of the resulting deformation signals were evaluated using Detrended Fluctuation Analysis (DFA), thereby assessing randomness and long-range dependence. Complementarily, the Continuous Wavelet Transform (CWT) was applied to spatially resolve deformation energy and to delineate critical damage hotspot areas along the road alignment. Google Earth Engine-based remote sensing validation was also incorporated. These results provide a quantitative and mathematically grounded interpretation of post-event geometric irregularities and the inferred deformation processes driven by soil–structure interaction and liquefaction phenomena. Collectively, the study underscores the efficacy of fractal and wavelet-based analytical frameworks as robust decision-support tools for post-earthquake damage evaluation and for informing prioritization of targeted rehabilitation and mitigation strategies.]]></description>
      <pubDate>Wed, 30 Sep 2026 09:29:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2732955</guid>
    </item>
    <item>
      <title>Research on the Influence of Reduction Rate in Asynchronous Rolling on Magnesium Alloy AZ31 Thin Sheet</title>
      <link>https://trid.trb.org/View/2742590</link>
      <description><![CDATA[A finite element analysis was conducted on the plastic deformation of 6 mm AZ31 magnesium alloy thin plates rolled asynchronously. Different reduction rates were adopted to analyze their influences on the bending deformation, rolling force, equivalent stress, and equivalent strain of the plates. The finite element analysis of asynchronous rolling was carried out when the single-pass reduction rates were 66%, 58.3%, 51.6%, 41.6%, and 35%, respectively. The results show that as the reduction rate decreases, the rolling force increases. Furthermore, considering the influencing factors of the rolling process parameters, it is determined that when the optimal rolling process reduction rate is 41.6%, the rolling effects of rolling force, stress, and strain are better, which is conducive to the rolling process.]]></description>
      <pubDate>Tue, 29 Sep 2026 15:46:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2742590</guid>
    </item>
    <item>
      <title>Static and Dynamic Performance Analysis and Parametric Optimization of Five-Axis Ultra-Precision Machine Tool via FEM</title>
      <link>https://trid.trb.org/View/2742588</link>
      <description><![CDATA[The static-dynamic behaviors of ultra-precision five-axis machine tools are the core factors to ensure sub-micron-level machining accuracy. This study establishes a detailed finite element model of an entire machine based on the ANSYS Workbench platform and conducts in-depth research on the static-dynamic characteristics of the entire machine of the ultra-precision five-axis machining center by using the finite element analysis(FEM) method and combining the principles of statics and dynamics. By constructing an accurate finite element model, the stress distribution, deformation, and modal vibration characteristics of the entire machine, especially the key parts, such as spindle box, crossbeam, column, and guide rails, under complex loads such as gravity and cutting force are simulated. The static analysis reveals a maximum deformation of 0.17 mm in the spindle box and the column, and the maximum stress is 58 MPa (at the Z-direction guide rail contact point), which is lower than the allowable stress of Q215 steel (195.5 MPa). The modal analysis extracts the first six natural frequencies (50.683 - 175.91 Hz), and the low-order vibration modes are mainly the Y/X-direction swing of the column, revealing the weak stiffness links. Based on the analysis results, a parametric optimization method was further adopted to optimize the structure of the weak components: the base, the column and the spindle box. This significantly enhanced the overall stiffness, reducing the maximum deformation to 0.039 mm and the maximum stress to 45MPa. The first six natural frequencies were all greatly increased (the first one reaching 85.548Hz). These findings provide valuable insights for machine tool structural enhancement and performance optimization.]]></description>
      <pubDate>Tue, 29 Sep 2026 15:46:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2742588</guid>
    </item>
    <item>
      <title>Integration advancements in bridge deformation monitoring: an ensemble approach combining LightGBM and XGBoost</title>
      <link>https://trid.trb.org/View/2775020</link>
      <description><![CDATA[Bridge deformation monitoring is essential for ensuring structural integrity and safety. Despite significant advances in predictive modeling, existing methods often struggle to achieve both accuracy and robustness, particularly when handling multi-sensor data. This study proposes a loss-driven ensemble of Light Gradient Boosting Machine (LightGBM) and Extreme Gradient Boosting (XGBoost) to improve Global Navigation Satellite System (GNSS)-based bridge deformation prediction. The predictions of the models are combined using weights derived from training loss, leveraging LightGBM computational efficiency and XGBoost ability to capture complex nonlinear patterns. This strategy enhances robustness, and effectively handles noisy, heterogeneous multi-sensor data. Experimental results demonstrate the effectiveness of the ensemble, achieving a Mean Absolute Error of 2 mm, corresponding to an approximately 60% improvement over traditional methods. These findings highlight the model ability to accurately and consistently capture deformation patterns. The proposed LightGBM-XGBoost ensemble achieves high accuracy, scalability, and robustness, making it well-suited for real-time and large-scale bridge monitoring in practical engineering applications.]]></description>
      <pubDate>Mon, 28 Sep 2026 16:46:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2775020</guid>
    </item>
    <item>
      <title>Transient Deformation Analysis of a Peat Foundation Under Heavy-Haul Railway Loading</title>
      <link>https://trid.trb.org/View/2752207</link>
      <description><![CDATA[A three-dimensional finite-difference model was developed to identify the mechanisms governing lateral deformation in a peat-supported heavy-haul railway embankment at the Anzac site, Alberta, Canada. ShapeAccelArray measurements showed that the maximum lateral deformation occurred near the peat–silty clay interface and could not be reproduced using a conventional layered representation of the foundation. Site-specific peat properties derived from laboratory testing were used in the moving-load analyses, while sensitivity analyses evaluated the effects of boundary conditions, stiffness contrast, interface behavior, and loading configuration. The conventional model placed the maximum deformation within the peat, whereas a thin layer of weak material at the peat–silty clay interface reproduced the measured depth-dependent lateral deformation profiles. Static point-load analyses captured the dominant transverse response but underestimated longitudinal deformation. Moving-load simulations reproduced the measured deformation trends parallel and perpendicular to the track. Maximum shear strain increments were concentrated near the peat–silty clay interface and attenuated within the underlying silty clay. The results showed that localized interface behavior, foundation stiffness contrast, and load progression governed the observed lateral deformation response.]]></description>
      <pubDate>Mon, 28 Sep 2026 08:37:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2752207</guid>
    </item>
    <item>
      <title>Automated Finite Element Modeling and Predictive Assessment of Deformation in HSR Bridge–Embankment Transition Zones on Soft Soil</title>
      <link>https://trid.trb.org/View/2752205</link>
      <description><![CDATA[The construction of high-speed railway (HSR) bridges and approach embankments over thick soft soil deposits presents significant geotechnical challenges, including excessive settlement, differential deformation, and lateral displacement. This study introduces an integrated numerical–predictive framework for evaluating the performance of HSR bridge abutments and transition embankments on soft ground, with particular emphasis on the Mekong Delta region of Vietnam. Two-dimensional finite element analyses were conducted to examine the influence of prestressed high-strength concrete pile length and diameter, braking force, and vertical train load on the settlement and lateral displacement of the abutment. The preliminary results demonstrated that the combined pile–geocell reinforcement system significantly reduced both total and differential settlements while enhancing deformation capacity within the transition zone. Numerical simulations were subsequently used to develop predictive equations for settlement and lateral displacement using Gene Expression Programming. The developed models demonstrated satisfactory predictive capability and successfully captured the nonlinear interactions among loading and reinforcement variables. The parametric study further indicated that emergency braking increased the lateral displacement, whereas longer piles substantially improved the deformation control. Overall, the proposed framework provided practical guidance for deformation assessment and preliminary design of HSR bridge–embankment transition systems over thick soft soil deposits.]]></description>
      <pubDate>Mon, 28 Sep 2026 08:37:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2752205</guid>
    </item>
    <item>
      <title>Coordinate-preserving degradation-knee mapping for Kriging relevance mechanisms in FFD-based hull-form optimization</title>
      <link>https://trid.trb.org/View/2774621</link>
      <description><![CDATA[Free-form deformation (FFD)-based hull-form optimization must balance geometric design freedom, limited CFD budgets and interpretable surrogate modeling. This study develops a coordinate-preserving degradation-knee mapping framework for Kriging relevance mechanisms in FFD engineering subspaces. A grouping-matrix formulation separates the geometric resolution of a fixed FFD lattice from the statistical input dimension of the surrogate, while a hierarchical dimension-calibrated engineering-grouped precision metric, termed HD-EGP, decomposes the Kriging precision matrix into a total precision budget, group-level relevance proportions and trace-normalized within-group precision shapes. Controlled benchmarks map the applicability and degradation behavior of five relevance mechanisms across response structures, dimensions and sample-density ratios, with HD-EGP providing a balanced combination of predictive applicability, probabilistic calibration and relevance stability while preserving the original engineering coordinates. These mechanism-level findings are transferred to CAESES–SHIPFLOW hull-form data to identify a region-wise FFD subspace supported by the available CFD information and to guide surrogate-assisted calm-water resistance optimization. SHIPFLOW recomputation confirms a 4.38% reduction in total resistance within the prescribed ±1% displacement-volume constraint. The learned relevance allocations remain attached to the original region–direction controls, providing a region-resolved surrogate diagnostic for hull refinement. The framework therefore links CFD-budget-aware FFD subspace selection, coordinate-preserving relevance learning and high-fidelity verification within a unified hull-design workflow.]]></description>
      <pubDate>Mon, 28 Sep 2026 08:37:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2774621</guid>
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