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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=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7U2hvY2smcXVvdDsiIG9yaWdpbmFsX3ZhbHVlPSImcXVvdDtTaG9jayZxdW90OyIgLz48L2ZpbHRlcnM+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>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Protection performance of fiber reinforced foamed concrete anti-collision device for bridges under ship impact</title>
      <link>https://trid.trb.org/View/2700875</link>
      <description><![CDATA[Recent years have witnessed an increase in ship-bridge collision accidents globally, with these accidents causing both tragic loss of lives and substantial economic damages. To enhance bridge structures protection, this paper proposes an anti-collision device utilizing fiber reinforced foamed concrete. The device consists of a steel shell and in-fill fiber reinforced foamed concrete, which is installed around bridge piers or bearing platforms in the form of fenders to resist ship impact and provide protection for bridges. Static compression test was conducted on foamed concrete specimens with different fiber dosages to analyze the damage mode and energy absorption characteristics. The fiber dosage with the optimal compressive strength and energy absorption effect was selected to fabricate the anti-collision device for horizontal impact test. The device’s energy absorption effect and anti-collision performance were analyzed. ANSYS/LS-DYNA was used to numerically simulate the horizontal impact test, and the results of simulation matched well with the test. On this basis, numerical simulations were carried out for practical engineering applications. The results illustrated that 0.8 kg/m3 was the optimal fiber dosage with the highest compressive strength and the best energy absorption effect. Both experimental and simulation results confirmed that the proposed device provided superior anti-collision performance, validating its effectiveness. The numerical simulation of engineering applications further validated its value of practical application.]]></description>
      <pubDate>Fri, 28 Aug 2026 08:34:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2700875</guid>
    </item>
    <item>
      <title>Characterizing TC128 Steel Plasticity for Finite Element Modeling</title>
      <link>https://trid.trb.org/View/2764020</link>
      <description><![CDATA[The Federal Railroad Administration, through a research program to improve transportation safety for tank cars, sponsored the Volpe National Transportation Systems Center to develop and compare techniques to simulate the plastic stress-strain behavior of Association of American Railroads’ TC128, Grade B (TC128) steel [1]. TC128 steel is used in the construction of tank cars designed to carry hazardous materials. This research took place between 2019 and 2025.]]></description>
      <pubDate>Tue, 25 Aug 2026 08:59:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2764020</guid>
    </item>
    <item>
      <title>Design-oriented equivalent impact pulse construction and interpretable response prediction for high-speed railway bridge piers under pier-top impact</title>
      <link>https://trid.trb.org/View/2736649</link>
      <description><![CDATA[Accurate and efficient representation of pier-top impact effects remains a challenge in whole-bridge seismic analysis. Contact-element-based approaches are often highly sensitive to the selected time step and contact stiffness, while existing equivalent dynamic load methods are frequently derived from static equivalence, empirical pulse assumptions, or local force-based criteria, and therefore may not adequately reflect the actual structural demand. To address this issue, this study develops a mechanics-informed and design-oriented framework for simplifying pier-top impact on high-speed railway bridge piers. A spring-mass-beam impact model (SMBIM), previously validated by scaled impact tests, is adopted as the computational backbone to generate a parametric database covering representative bridge and impact conditions. A displacement-based equivalent pulse strategy (DEPS) is then proposed to define the duration of an equivalent rectangular pulse by enforcing peak-displacement equivalence, so that the impact effect can be directly incorporated into structural analysis without explicitly simulating the full contact process. To identify the dominant mechanisms governing local and global response quantities, feature-ranking and partial-dependence analyses are performed for the peak impact force, maximum pier-top displacement, and equivalent duration. Based on these insights, explicit power-law formulas are established for transparent and rapid estimation of these key quantities. Validation against a held-out numerical testing subset shows that the proposed explicit formulas for the peak impact force, maximum pier-top displacement, and equivalent duration achieve coefficients of determination of 0.950, 0.898, and 0.904, respectively, with mean relative errors below 6.5%. Representative verification cases further indicate that the equivalent rectangular pulse reproduces the peak displacement of the SMBIM with errors generally below 2%. The proposed framework provides a computationally efficient and interpretable alternative to detailed contact-impact simulation for design-level assessment of impact effects within the investigated parameter range.]]></description>
      <pubDate>Wed, 19 Aug 2026 09:26:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2736649</guid>
    </item>
    <item>
      <title>Comfort Study of Air Suspension System Based on MPC Control</title>
      <link>https://trid.trb.org/View/2742523</link>
      <description><![CDATA[Air springs are increasingly replacing traditional shock absorbers in vehicle suspension systems due to their superior mechanical properties, including adjustable stiffness, nonlinear characteristics, and excellent damping performance. To further explore the potential of air suspension in improving ride comfort, this paper focuses on air suspension. We first conducted mechanical characteristic experiments on air springs to obtain their stiffness and damping characteristics under different inflation pressures and excitation frequencies. These tests provide essential mechanical parameters for subsequent modeling and simulation. Based on the experimental data, a simplified 1/4 air suspension simulation model is constructed, taking into account the nonlinear stiffness and damping properties of the air springs. To simulate real-world driving conditions, a random road surface model is introduced as the excitation input. Simulation analysis is conducted to compare the air suspension system with the traditional passive suspension system. The results indicate that, compared to the passive suspension system, the air suspension system integrated with Model Predictive Control(MPC) significantly reduces key performance indicators, including suspension deflection, wheel dynamic load, and sprung mass vertical acceleration. This indicates that the suspension with model predictive control can effectively suppress vehicle vibrations, thereby enhancing ride comfort and driving stability. The results of this study provide an important basis for the optimal design of air suspension systems and have practical application value for improving the suspension performance of the vehicle.]]></description>
      <pubDate>Mon, 03 Aug 2026 15:36:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2742523</guid>
    </item>
    <item>
      <title>Dynamic Analysis of Micromobility in-Wheel Suspension System – Enhancing Safety in Urban Environments</title>
      <link>https://trid.trb.org/View/2691518</link>
      <description><![CDATA[Micromobility has emerged as a major global trend in urban transportation. However, it has also led to a rise in accidents, largely attributed to improper usage and inadequate safety precautions. This paper presents a model developed for the dynamic analysis of an in-wheel suspension system for micromobility vehicles, along with proposals for its improvement. The model accounts for challenges related to urban infrastructure, particularly variation in various obstacle types and heights on cycle road pavement, using the city of Vilnius (Lithuania) as a case study. The research paper additionally evaluates factors affecting rider safety and risk, with a primary focus on in-plane dynamics. The dynamic analysis demonstrates that the in-wheel suspension system enhances riding safety across simulated variations. These findings help identify critical vertical dynamic risks for micromobility in urban area and offer insights for future city’s road infrastructure planning. © 2026 Faculty of Transport and Traffic Engineering. All rights reserved.]]></description>
      <pubDate>Tue, 21 Jul 2026 09:50:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691518</guid>
    </item>
    <item>
      <title>Impact Attenuation Assessment of Several Lightweight Materials Subjected to a Motorcycle Helmet Free-Fall Drop Test</title>
      <link>https://trid.trb.org/View/2581403</link>
      <description><![CDATA[The paper focuses on the analysis of the impact behavior of some light materials used either for shock absorption inside protective helmets or as support materials. Five types of structures were analyzed, subjected to three different impact speeds. A dummy head used in accidentology tests was mounted on the impact head, and in the second stage a motorcycle helmet was fixed on the dummy head. The results revealed that tested materials can lead to an improvement in impact mitigation performance. Thus, it was proven that the use of the protective helmet leads to a decrease in acceleration and impact force by: 48.8% in the case of impact at a speed of 3.13 m/s; 25.1% in the case of the impact at the speed of 4.42 m/s and 31.9% in the case of the impact at the speed of 5.42 m/s.]]></description>
      <pubDate>Mon, 13 Jul 2026 10:46:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2581403</guid>
    </item>
    <item>
      <title>Multi-objective optimization of crashworthiness for double-layer thin-walled tube composite anti-climb energy-absorbing device in subway vehicles</title>
      <link>https://trid.trb.org/View/2691025</link>
      <description><![CDATA[To enhance the crashworthiness of subway vehicles, this study presents a novel hybrid anti-climb energy-absorbing device. It integrates inner and outer double-layer thin-walled square tubes with honeycomb structures for synergistic energy absorption. To analyze the energy absorption characteristics of the anti-climb energy-absorbing device, collision simulations were conducted by mounting the device on the front end of a test trolley. Based on Optimal Latin hypercube sampling (OLHS), a Kriging surrogate model characterizing energy absorption (EA) and peak crushing force (PCF) was developed for the parameters of aluminum honeycomb average crushing stress (c), partition thickness (t₁), thin-walled outer tube thickness (t₂), and thin-walled inner tube thickness (t₃). The main effects of parameters on EA and PCF were analyzed, and the results indicated that t₂ exerted the most significant influence on the energy absorption characteristics. Multi-objective optimization via the Non-dominated Sorting Genetic Algorithm II (NSGA-II algorithm) was implemented for different vertical offset conditions (h = 0 mm and 40 mm), simultaneously maximizing EA while minimizing PCF. The optimal solution is identified at c = 3.9 MPa, t₁ = 4 mm, t₂ = 2.9 mm, and t₃ = 2.4 mm, with the surrogate model’s prediction errors relative to finite element simulation results below 10%. Collision simulations of 6-car subway vehicles demonstrated that key collision indicators all met the requirements of the EN15227 standard, verifying that the device exhibits excellent energy absorption and anti-climb performance, and providing critical references for its optimized design and application in subway vehicles.]]></description>
      <pubDate>Mon, 13 Jul 2026 10:45:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691025</guid>
    </item>
    <item>
      <title>A comprehensive simulation approach for planning single-axis bench tests of vehicle shock absorbers</title>
      <link>https://trid.trb.org/View/2680752</link>
      <description><![CDATA[An integrated simulation-based approach is proposed for planning single-axis bench tests for evaluating the ability of vehicle shock absorbers to withstand the multi-axis acceleration, deceleration and steering forces produced under real-world driving conditions. In the proposed framework, multi-body dynamic analysis and computer-aided engineering (CAE) simulations are first performed to identify the regions of maximum stress produced in the four-wheel suspension system under seven representative driving conditions. Further finite element simulations are then performed to predict the regions of maximum stress in the shock absorber in three single-axis bench tests performed with the load applied at different positions of the absorber and in different directions. It is shown that, between them, the three single-axis bench tests successfully induce the same regions of maximum stress as those observed in the CAE simulations under the different driving conditions. The simulation results obtained in the bench tests for the variation of the shock absorber deformation with the applied load are used to determine the maximum loading forces and deformations the shock absorber can resist under vertical and lateral loading conditions, respectively. The feasibility of the early-stage shock absorber design can then be evaluated by confirming that the maximum deformation experienced by the shock absorber under real-world driving conditions (multipled by a given safety factor) falls within this maximum loading force range. The method proposed in this study provides a low-cost and systematic approach for planning the single-axis bench tests and evaluation criteria required to confirm the ability of shock absorbers to meet vehicle suspension requirements under real-world driving conditions.]]></description>
      <pubDate>Tue, 30 Jun 2026 15:52:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2680752</guid>
    </item>
    <item>
      <title>Fast charging shock-nonlinear degradation coupled model for battery remaining useful life prediction</title>
      <link>https://trid.trb.org/View/2684308</link>
      <description><![CDATA[Fast charging technology accelerates the degradation of lithium-ion batteries and introduces random fluctuations, hence complicating the accurate forecast of Remaining Useful Life (RUL). Traditional battery degradation models are difficult to simultaneously capture the continuous attenuation within the battery and the external shock damage caused by fast charging events. This model innovatively combines the nonlinear degradation process of the battery with the Non-Homogeneous Poisson Process (NHPP) used to characterize the discrete damage caused by fast charging shock. This framework can quantitatively distinguish between two key failure paths: “system failure” caused by the combined effect of intrinsic degradation and cumulative shock, and “shock failure” directly triggered by cumulative shock damage. Furthermore, a comprehensive estimation scheme incorporating offline parameter identification and online Bayesian updating was established to ensure model adaptability under dynamic operating conditions. Validation using real-world electric vehicle operation data demonstrates that, compared with the traditional linear Wiener model, the proposed coupled model reduces the Mean Absolute Error (MAE) by over 70% and maintains a prediction error within 5%. These results confirm the significant advantages of the proposed model in terms of both RUL prediction accuracy and reliability.]]></description>
      <pubDate>Tue, 23 Jun 2026 13:53:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/2684308</guid>
    </item>
    <item>
      <title>Evaluation of Dynamic Response for Freeze–Thaw Damaged RC Beams Subjected to Impact Loading</title>
      <link>https://trid.trb.org/View/2616167</link>
      <description><![CDATA[The impact resistance of in-service freeze-thaw damaged reinforced concrete (RC) bridges is a hot issue in the engineering field. Drop weight impact tests were conducted on RC beams after freeze-thaw cycles (FTCs), and the failure modes and dynamic impact responses were investigated. As the number of FTCs improved, RC beams transitioned from flexural to flexural-shear failure, tending to transition toward shear failure after 125 cycles. With the increase in the degree of freeze-thaw damage, the peak impact force and impact response duration of the RC beams decreased, and the impact energy dissipation was also significantly reduced. Conversely, the peak midspan deflection initially decreased and subsequently increased. Considering the uneven distribution of freeze-thaw damage from the surface to the interior of the concrete, a two-degree-of-freedom model for RC beams subjected to FTCs under impact loading was established. The proposed model can reflect the impact dynamic response process of the beams and shows good agreement with the experimental data.]]></description>
      <pubDate>Wed, 17 Jun 2026 16:14:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2616167</guid>
    </item>
    <item>
      <title>Research on drop shock dynamic performance of air-cushion aircraft on ground and water surface</title>
      <link>https://trid.trb.org/View/2698509</link>
      <description><![CDATA[Aircraft with traditional landing gear have difficulty adapting to complex take-off and landing environments such as water, sand and uneven surfaces. In this study, simulations and experiments of the ground and water landing performances of an amphibious air-cushion aircraft were conducted to demonstrate its amphibious landing capabilities. Based on membrane and gas thermodynamics theories, the dynamic response problem of a transport aircraft with an air cushion landing system (ACLS) was investigated. First, the shape prediction curve of the airbag was designed and implemented in MATLAB/Simulink based on membrane theory and the finite element method, and then the mass–volume–pressure of the airbag in the ACLS was calculated according to the ideal gas equation of state. Second, considering the fluid-structure interaction effects of the air cushion water entry, dynamic models of the air-cushion aircraft on the ground and under calm water surface were established in MATLAB/Simulink to study the dynamic performance of the air-cushioned aircraft. Finally, test and simulation analyses were conducted to study the dynamic responses of the air-cushion aircraft. The maximum cavity pressure and vertical acceleration grew larger as the drop height increased, and they both converged to stability quickly. The fuselage and air cushion had good dynamic responses in the process of both ground and water landing, and the amphibious landing capability of the air-cushion aircraft was verified. This study can provide guidance for the structural and control system design of an air-cushion aircraft and lay a foundation for the water drop dynamic analysis of air-cushion aircraft.]]></description>
      <pubDate>Thu, 21 May 2026 16:28:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2698509</guid>
    </item>
    <item>
      <title>Analysis of the Effect of Brackish Water on the Mechanical Properties of 'Gigantochloa Apus' Bamboo Laminated Board for Ship Hull Material</title>
      <link>https://trid.trb.org/View/2703861</link>
      <description><![CDATA[The maritime industry faces increasing pressure to use sustainable materials for ship construction, especially in brackish water, which is common in estuarine regions of Indonesia. As an alternative to steel, bamboo laminated board composites represent a notable innovation. This article comprehensively analyzes the mechanical properties of bamboo laminated boards made from 'Gigantochloa apus' when exposed to brackish water conditions. The research includes a series of experiments involving the number of bamboo laminate layers, immersion periods, and immersion environment conditions. The mechanical properties of the bamboo laminated boards – including impact, bending, and tensile strength – were carefully evaluated and compared to the Indonesian Classification Bureau (BKI) standard as a safety requirement. The results reveal a complex relationship among the number of layers, immersion time, brackish water temperature, and the performance of bamboo laminated boards. Our research indicates that 'Gigantochloa apus' bamboo laminated boards exhibit remarkable resistance to brackish water, maintaining structural integrity and resilience over time, in contrast to other materials. As immersion time varied, the mechanical strength properties of all layer variations decreased by approximately 5 to 9 percent. According to data analysis and comparison with BKI standard safety regulations, apus bamboo laminated board is suitable for ship hulls. © 2026, Faculty of Maritime Studies. All rights reserved.]]></description>
      <pubDate>Wed, 20 May 2026 09:10:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2703861</guid>
    </item>
    <item>
      <title>Numerical simulation and dynamic response analysis of a ship–train–bridge system under vessel collision</title>
      <link>https://trid.trb.org/View/2683015</link>
      <description><![CDATA[Bridge train derailments are among the most common and severe consequences of ship collisions with bridges. This study simulates the dynamic response of bridges and trains under such collisions using finite element analysis, integrating practical engineering considerations. The paper analyzes and calculates the dynamic response of both the train and the bridge structure under ship collision by establishing a ship-train-bridge coupled model. Building upon previous numerical simulations of ship-pier collisions, this paper closely focuses on the Chongqi Railway-Highway Bridge, constructing a detailed simulation model that closely mirrors the actual structure. Simulations and verifications of sea-river ship’s impacts were performed and a system model for ship-vehicle-bridge dynamic coupling was established. Through finite element analysis, an in-depth examination of this coupled system was conducted. The numerical results indicate that ship collision significantly intensifies the dynamic response of the train-bridge system: the risk of train derailment rises sharply, with transverse vibrations far exceeding those in a no-impact scenario, challenging system stability. At the same time, the transverse displacement and acceleration in the mid-span region of the bridge show a significant increase, which further highlights the profound impact of the impact on the transverse dynamic response of the bridge structure. Additionally, the train's operating speed and its specific position on the bridge significantly impact the safe train operation, while the train's location on the bridge directly affects the lateral dynamic response of the bridge structure.]]></description>
      <pubDate>Tue, 19 May 2026 15:12:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2683015</guid>
    </item>
    <item>
      <title>Study on the collision between a ship and ice ridge considering macro-porosity in ice</title>
      <link>https://trid.trb.org/View/2681486</link>
      <description><![CDATA[The opening of Arctic shipping routes enables shorter voyages and enhances economic efficiency. An ice ridge, a typical extreme ice condition in polar regions, generates ice loads during interactions with structures; they are commonly designated as ultimate design loads in polar marine and offshore engineering. Field observations reveal that macro-porosity, a distinctive characteristic of ice ridges arising from their complex formation processes, significantly influences mechanical properties of the ice ridge and ice load behavior. To analyze the load and fracture characteristics of ice ridges, model tests of the icebreaker-ice ridge collision were conducted in an outdoor ice tank. Based on the experimental data, two numerical ice ridge models incorporating various macro-porosity modelling were developed and validated. The interaction processes between ice ridges and structures were simulated, with keel depths analyzed for their effects on failure mechanisms of the ice ridge and ice loads. The failure progression under multiple impacts and the number of collisions required to damage the ice ridge were further investigated. These findings aim to provide some practical references for icebreaker structural design and operational strategies.]]></description>
      <pubDate>Thu, 14 May 2026 17:05:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/2681486</guid>
    </item>
    <item>
      <title>Analysis of dynamic response mechanism and control measures for tunnel crossing mountainous landslides: A shaking table test study</title>
      <link>https://trid.trb.org/View/2663878</link>
      <description><![CDATA[In seismically active mountainous regions, the dynamic response mechanisms and associated control measures of the earthquake–tunnel–landslide system (ETLS) have become a major research focus in the field of geotechnical engineering. In this study, a shock-absorbing layer (SAL) was adopted as a seismic control measure for the tunnel lining, and a physical model was developed in which the tunnel orthogonally undercrosses the main sliding surface of a landslide (TULS), and comparative seismic dynamic tests were subsequently conducted. In addition, the variational mode decomposition–Hilbert transform (VMD-HT) approach was employed to elucidate the seismic damage evolution of the TULS from the perspectives of energy distribution and frequency shift. The results demonstrate that the VMD-HT method exhibits clear advantages in the separation and extraction of the dominant frequencies of seismic signals, enabling precise decomposition of individual signal components. The dynamic failure of the TULS arises from the coupled interaction among the active movement of the sliding mass, the passive resistance of the tunnel, and seismic loading, and is characterized by a distinct four-stage evolutionary process. Among these, the concentration of shear stress along the main sliding surface is identified as the primary trigger for damage to the tunnel lining structure. With the incorporation of the SAL, the dynamic response of the tunnel lining is significantly reduced compared with the unprotected condition. The SAL effectively mitigates the energy impact of high-frequency components of seismic motions on the structure and slows the damage evolution of the tunnel lining.]]></description>
      <pubDate>Mon, 11 May 2026 08:50:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2663878</guid>
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