<?xml version="1.0" encoding="utf-8"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>TRB Publications Index</title><link>http://pubsindex.trb.org/</link><atom:link href="http://pubsindex.trb.org/common/TRIS Suite/feeds/rss.aspx?s=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJzdWJqZWN0aWQiIHZhbHVlPSIxNzc5IiAvPjxwYXJhbSBuYW1lPSJsb2NhdGlvbiIgdmFsdWU9IjIiIC8%2BPHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8%2BPC9wYXJhbXM%2BPGZpbHRlcnMgLz48cmFuZ2VzIC8%2BPHNvcnRzPjxzb3J0IGZpZWxkPSJwdWJsaXNoZWQiIG9yZGVyPSJkZXNjIiAvPjwvc29ydHM%2BPHBlcnNpc3RzPjxwZXJzaXN0IG5hbWU9InJhbmdldHlwZSIgdmFsdWU9InB1Ymxpc2hlZGRhdGUiIC8%2BPC9wZXJzaXN0cz48L3NlYXJjaD4%3D" rel="self" type="application/rss+xml" /><description></description><language>en-us</language><copyright>Copyright © 2015. 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>TRB Publications Index</title><url>http://pubsindex.trb.org/Images/PageHeader-wTitle.png</url><link>http://pubsindex.trb.org/</link></image><item><title>Investigating Nonmotorist Crash Exposure at Highway–Rail Grade Crossings Using Artificial Intelligence-Based Object Detection and Generalized Linear Count Models</title><link>http://pubsindex.trb.org/view/2703807</link><description><![CDATA[A critical aspect of crash prediction models for highway–rail grade crossings (HRGCs) is crash exposure, which is a measure of train and highway traffic. Although data on motor vehicle traffic (e.g., annual average daily traffic) and train traffic at HRGCs are invariably available, nonmotorist traffic data at HRGCs are not readily available. Current Federal Railroad Administration and other HRGC crash models focus on train and motor vehicle traffic, overlooking nonmotorized traffic. Therefore, there is a need to gather nonmotorized traffic data to improve HRGC crash prediction models. To address this gap, nonmotorist traffic video data were recorded in this study at various urban and suburban HRGCs in Nebraska, followed by the application of an artificial intelligence-based You Only Look Once (version 8) algorithm for automated nonmotorist traffic volume detection. Data on HRGC characteristics, including surrounding area population density and land use, were collected to create a comprehensive HRGC safety database for nonmotorists. Three negative binomial models were estimated to analyze pedestrian, bicyclist, and combined nonmotorist exposure in relation to daily volumes, utilizing physical, dynamic, and temporal characteristics of HRGCs. Results indicated that sidewalks, greater visibility, and cloudy weather conditions were associated with increased nonmotorist traffic volume. Conversely, higher vehicular traffic levels, wet road conditions, low population density, and more traffic lanes correlated with lower nonmotorist traffic. This study established an initial framework for nonmotorist traffic monitoring and identified key environmental and technical challenges in automated detection at HRGCs; based on these findings, recommendations for addressing technical limitations were provided for future research.]]></description><pubDate>Tue, 19 May 2026 09:02:16 GMT</pubDate><guid>http://pubsindex.trb.org/view/2703807</guid></item><item><title>Assessing Railway Track Embodied Carbon: Life Cycle Inventory Literature Review</title><link>http://pubsindex.trb.org/view/2701139</link><description><![CDATA[Efforts to reduce carbon emissions have intensified across the transportation sector, yet life cycle inventory (LCI) data describing the global warming potential (GWP) of railway infrastructure remain limited in the U.S. context. Existing literature is dominated by non-U.S. studies and often aggregates track infrastructure GWP with other civil structures, limiting transparency and applicability. This study synthesized LCI data from 116 case studies reported across 53 sources and isolated at-grade railway track infrastructure. Foreground and background inventory data were compiled for track components, construction and maintenance equipment, material transportation, and end-of-life (EOL) treatment. Case studies were harmonized to a common track-kilometer-per-year functional unit to enable cross-comparison of track GWP. More than 75% of case studies originate from Europe, with concrete-tie and slab-track systems accounting for 74% of all cases, while wooden-tie tracks are underrepresented (10%). EOL treatment data are reported in only 10 studies, and maintenance-cycles are included in approximately half of the sources. The Ecoinvent database is used in 26 studies, while only four incorporate U.S. LCI datasets. Material-level inventories show substantial variability in GWP factors, particularly for steel (0.4–5.7 kg CO₂e/kg), whereas aggregates exhibit the lowest impacts (∼10 g CO₂e/kg). Fuel emissions from maintenance-of-way equipment and material transportation are regarded minor contributors (2%–10% of track GWP). After normalization, overall track GWP converges to a narrow range (21.6–25.7 t CO₂e/km/year) across track systems, indicating that system boundaries and background data choices influence results more than track type. The review also highlighted a critical need for U.S.-specific LCI datasets and environmental product declarations.]]></description><pubDate>Tue, 12 May 2026 16:57:36 GMT</pubDate><guid>http://pubsindex.trb.org/view/2701139</guid></item><item><title>Effect of Sand Grading and Proportion on the Performance of Cement Asphalt Mortar for High-Speed Rail Slab Track Systems</title><link>http://pubsindex.trb.org/view/2701133</link><description><![CDATA[Sand makes up about 40% of cement asphalt mortar (CAM) used in non-ballast tracks for high-speed rail infrastructure, playing a crucial role on the performance of CAM. This study investigates the influence of sand gradation (quantified using fineness modulus [FM]), and sand-to-cementitious component ratio (S/CC) on key CAM parameters, including flow time, working time, material separation, compressive strength, elastic modulus, and shrinkage. Multiple gradations and S/CC ratios were evaluated to establish combinations that achieve the required flow time (16–28 s), a minimum 30 min working time, minimize material separation, and ensure desired mechanical performance. Results indicate that coarser gradations improve workability but increase material separation, whereas finer gradations reduce separation but prolong flow time. An FM of 1.6, with particles passing 1.18 mm sieve ensure desired flow time and homogeneity of CAM. An S/CC ratio of 2 maintained good workability, reduced shrinkage and deformation, and improved compressive strength and modulus. These findings offer insights for CAM mix design particularly with reference to sand gradation and proportion selection.]]></description><pubDate>Tue, 12 May 2026 16:57:36 GMT</pubDate><guid>http://pubsindex.trb.org/view/2701133</guid></item><item><title>BallastAttN: Occlusion-Robust 3D Railway Ballast Characterization using Data Synthesis and Deep Learning</title><link>http://pubsindex.trb.org/view/2701226</link><description><![CDATA[Accurate characterization of railway ballast is critical for track safety and maintenance; however, traditional field sampling/sieving or two-dimensional images captured are often labor-intensive and limited for a representative analysis. Three-dimensional (3D) point cloud analysis may offer a more comprehensive approach; the dense packing and heavy occlusion of ballast particles restrict image segmentation. This study introduces a novel deep learning pipeline designed for robust 3D railway ballast characterization, BallastAttN. Its core contributions include a comprehensive synthetic training data set from high-fidelity 3D scans of new and degraded ballast particles, an enhanced point cloud segmentation model upgraded with edge-aware voxelization and curriculum learning, and the novel BallastAttN partial point cloud completion model architected to reconstruct complete particle shapes from the highly incomplete views typical of field conditions. The proposed pipeline was comprehensively validated using controlled laboratory experiments with isolated and clustered configurations of real ballast particles in new and degraded conditions. The results show that BallastAttN consistently outperforms the baseline completion framework that utilizes an encoder–decoder architecture mechanism built on attention mechanisms across commonly used size and morphological properties. The performance gap widened substantially in clustered scenarios that are close to the field ballast appearance, demonstrating the model’s enhanced ability to handle occlusion. The predictions were precise in differentiating between new and degraded ballast based on morphological properties, such as 3D sphericity, the Flat and Elongated Ratio, and the Angularity Index. This study establishes a practical framework for automated ballast inspection, for example, with the use of an innovative ballast scanning vehicle developed, paving the way for more efficient and reliable railway ballast maintenance.]]></description><pubDate>Mon, 11 May 2026 12:24:46 GMT</pubDate><guid>http://pubsindex.trb.org/view/2701226</guid></item><item><title>Multistage Physics-Informed Signal Processing Framework for In-Motion Detection of Track Stiffness Irregularities Using Onboard Vibration Sensors</title><link>http://pubsindex.trb.org/view/2698381</link><description><![CDATA[With nearly 140,000 mi of track, railroads are central to North America’s transportation infrastructure, carrying over 40% of freight by ton-miles and serving millions of passengers annually. Maintaining the structural integrity of the track is essential for operational safety and economic efficiency. Integrity is compromised by stiffness changes caused by ballast degradation, subgrade settlement, aging ties, temperature-induced stresses, and repeated loading. Proactive track health monitoring systems are needed to detect such changes continuously under dynamic train loads. This paper presents a multistage physics-informed framework for the in-motion detection of track stiffness irregularities (TSIs), serving as a proxy for identifying potential defects. The proposed system uses onboard vibration measurements, processed through advanced signal processing techniques. The system consists of three modules, for data acquisition, change detection, and change classification. It operates on an edge-computing platform, allowing real-time processing, and achieves over 95% data compression. The change-detection module, emphasized in this paper, combines wavelet packet analysis, variational mode decomposition, and the Hilbert transform to extract instantaneous energy features from vertical acceleration signals. These features act as sensitive indicators of track stiffness variation. The method was validated through both simulation and offline field data. Simulations captured a wide range of TSIs, including abrupt changes, gradual transitions, and localized weak zones. Field validation confirmed the model’s ability to consistently detect recurring irregularity patterns along the track, without requiring any assumptions about their physical origin. These results demonstrate the robustness, scalability, and real-world applicability of the proposed approach for continuous rail infrastructure monitoring.]]></description><pubDate>Tue, 05 May 2026 10:16:53 GMT</pubDate><guid>http://pubsindex.trb.org/view/2698381</guid></item><item><title>Risk Control of the Automatic Train Supervision System in Rail Transit Systems: Under a Van der Pol Equation-Based Framework</title><link>http://pubsindex.trb.org/view/2697864</link><description><![CDATA[Automatic train supervision (ATS) systems are a core safety component in metro operations. Its redundant design results in extremely scarce failure data, rendering traditional data-driven risk analysis ineffective. Consequently, existing studies often substitute reliability analysis for risk analysis. To overcome the limitations of static and vague reliability methods, this study employs the van der Pol equation to dynamically quantify inherent risk oscillations in ATS systems, providing managers with actionable control measures. Our paper begins by analyzing ATS risk characteristics and examining the feasibility of using the van der Pol equation to model risk state changes. Then, we establish a risk state equation derived from this framework and analyze the system’s risk dynamics. Finally, to control risk, we integrate a risk control function into the equation. A case study of Beijing Metro Line 2 demonstrates the method’s applicability. The proposed methodology enables accurate risk state judgment, potential risk prediction, and precise control implementation. By applying differential equation theory, it reduces reliance on historical data or expert knowledge while addressing inaccuracies from missing critical data. This work establishes a novel framework for system risk control and offers practical guidance for operators.]]></description><pubDate>Sat, 02 May 2026 15:47:06 GMT</pubDate><guid>http://pubsindex.trb.org/view/2697864</guid></item><item><title>Assessing the Structural Performance of Bolted Rail Joints Employing Various Fishplate Models via Finite Element Analysis</title><link>http://pubsindex.trb.org/view/2697861</link><description><![CDATA[In railway tracks, fishplates are attached to each side of two rail ends and secured with four bolts, providing what is known as a bolted rail joint (BRJ). This rail joint is involved in complex interactions between multiple components under wheel loads, leading to stress and deformation of each component, potentially resulting in failures of the railway track. In this study, the different roles of selected fishplate models in the structural performance of a BRJ under static load are investigated using finite element analysis with ABAQUS CAE. Three fishplate models are examined: a thin cross-section, a thick cross-section, and a modified design. The first two models are currently used in rail transportation, while the novel modified version is designed to enhance the structural performance of BRJs. Preliminary results indicate that using the modified fishplate significantly reduces stress on the upper rail fillet and fishplate. Additionally, vertical displacement in both the rail and fishplate is diminished. These improvements are expected to increase the service life and reliability of BRJs, thereby contributing to safer and more cost-effective railway operations.]]></description><pubDate>Sat, 02 May 2026 15:47:05 GMT</pubDate><guid>http://pubsindex.trb.org/view/2697861</guid></item><item><title>Track Panel Twist Failures at the Rear of Turnouts: Insights from Track Recording Car and Trackside Measurements</title><link>http://pubsindex.trb.org/view/2691035</link><description><![CDATA[Railway turnouts are critical for operational flexibility but are costly assets, with maintenance costs significantly higher than those for open track. Twist failures in the transition zones at the rear of turnouts between long and short sleepers increase maintenance needs and can pose safety risks. In this study, track panel twist behavior in such a transition zone was investigated by combining long-term track recording car data with trackside measurements. A preliminary analysis of track recording car data statistically confirmed the criticality of the transition zone and was used to identify a turnout with twist issues for further investigation. Trackside measurements were conducted to evaluate the influence of axle weight and vehicle speed on twist. Results indicate a linear relationship between axle weight and twist, while speed showed no significant effect. A time series of twist derived from track recording car data for the same turnout, used for comparison with trackside data, revealed an almost linear progression of track panel twist over time, with tamping actions visibly but temporarily reducing twist. These findings enhance the understanding of twist behavior at the rear of turnouts. They provide a basis for future studies aimed at improving turnout designs and highlight the potential for proactive maintenance strategies to enhance safety and operational efficiency.]]></description><pubDate>Mon, 13 Apr 2026 16:48:10 GMT</pubDate><guid>http://pubsindex.trb.org/view/2691035</guid></item><item><title>Exploring the Influence of Cognitive Functions on Job Burnout and Career Plateauing: Mediating Role of Job Engagement among Railway Switchmen</title><link>http://pubsindex.trb.org/view/2691002</link><description><![CDATA[This research delves into the intricate dynamics between cognitive functions, job burnout, and career plateauing among railway switchmen in Islamic Republic of Iran Railways, focusing on the pivotal role of job engagement as a mediator. As cognitive capabilities influence how employees manage job stress and professional growth, this study uncovers how cognitive functions directly shape burnout levels and contribute to career stagnation. The findings reveal that higher cognitive engagement is a key factor in reducing burnout, while simultaneously fostering career advancement and mitigating plateauing. Job engagement emerges as a powerful mediator, offering railway switchmen not only a sense of purpose but also a crucial mechanism to combat both mental exhaustion and stagnation in their professional trajectory. This study provides actionable insights for organizations, advocating for strategies that enhance cognitive engagement and promote continuous career development, thereby improving overall employee well-being and performance. The implications extend to both theoretical frameworks and practical solutions, underscoring the importance of fostering a mentally stimulating work environment to combat burnout and career stagnation in high-demand sectors.]]></description><pubDate>Mon, 13 Apr 2026 16:48:10 GMT</pubDate><guid>http://pubsindex.trb.org/view/2691002</guid></item><item><title>Study of On-Site Monitoring Analysis and Protective Measures for Long-Distance Parallel Excavation and Underlying Metro Tunnels</title><link>http://pubsindex.trb.org/view/2689787</link><description><![CDATA[With the acceleration of urbanization, the development and utilization of underground space have become increasingly common, leading to growing concerns about the impact of long-distance parallel excavation of deep foundation pits on underlying subway tunnels. This paper focuses on a foundation pit project where the parallel distance between the excavation area and the subway tunnel reached 270 m, using a combination of field monitoring and numerical simulation to analyze the deformation characteristics of subway tunnels during long-distance parallel excavation. The research results indicate that, with the increase in parallel distance, both vertical and horizontal displacements of the tunnel significantly increase. Furthermore, the “hardening soil” constitutive model achieved great simulation accuracy in modeling the deformation behavior of the soil surrounding the tunnel. Subway tunnel deformation control can be approached from three aspects: offsetting the additional stress load, improving the soil stiffness, and reducing the overall additional stress load. This study provides data support for further research on the impact of such extreme conditions on subway tunnels and offers a reference for designing and constructing similar engineering projects.]]></description><pubDate>Thu, 09 Apr 2026 09:01:27 GMT</pubDate><guid>http://pubsindex.trb.org/view/2689787</guid></item><item><title>High-Speed Railway and Shrinking Cities: Role of Distance</title><link>http://pubsindex.trb.org/view/2685660</link><description><![CDATA[This paper develops a theoretical model grounded in new economic geography to analyze the nexus between high-speed railway (HSR) and the development of shrinking cities. Theoretical research shows that HSR is negatively correlated with the population size of shrinking cities and positively correlated with total factor productivity. To validate the propositions derived from the theoretical model, we conduct empirical tests using panel data of 74 shrinking cities in China from 2007 to 2022. The findings are as follows: 1) HSR significantly reduces the population size of shrinking cities, thereby exacerbating urban shrinkage. Moreover, HSR significantly boosts the total factor productivity of shrinking cities. 2) The effects of HSR on shrinking cities are heterogeneous because of the “distance from the regional central city.” HSR exacerbates the population outflow of shrinking cities located within 220 km of the regional central cities. Conversely, it promotes the population inflow of shrinking cities beyond this distance. An interesting observation is that HSR significantly stimulates the total factor productivity of shrinking cities within 220 km from regional central cities. However, beyond this distance, the total factor productivity of shrinking cities is not significantly boosted by HSR.]]></description><pubDate>Tue, 31 Mar 2026 10:14:38 GMT</pubDate><guid>http://pubsindex.trb.org/view/2685660</guid></item><item><title>Predicting Metro Tunnel Deformation from Adjacent Excavation Using a Nonlinear Shear-Considered Model</title><link>http://pubsindex.trb.org/view/2684244</link><description><![CDATA[To more accurately predict existing shield tunnel deformation induced by adjacent excavation, this study developed a nonlinear Pasternak–Timoshenko model (NPTM). The model innovatively integrates nonlinear soil response with the tunnel’s structural shear deformation. Validation against a finite element model and two engineering cases confirmed the NPTM’s reliability. A key finding was that for wide excavations, soil nonlinearity dominated, and the deformation peak occurred at the excavation edge. Conversely, for narrow excavations, the tunnel’s structural shear behavior was more critical. Parametric analysis revealed deformation was highly sensitive to the pit–tunnel distance, d, and soil undrained shear strength, Sᵤ. Quantitatively, the benefit of increasing Sᵤ diminished significantly when Sᵤ exceeded 80 kPa. This suggests an economic threshold for ground improvement. Furthermore, deformation attenuated sharply when the pit–tunnel distance, d, exceeded 15 m. The model provides a practical, preliminary design tool for helping engineers to identify critical deformation zones and optimize protective measures.]]></description><pubDate>Thu, 26 Mar 2026 13:38:05 GMT</pubDate><guid>http://pubsindex.trb.org/view/2684244</guid></item><item><title>Low-Impact Frog Design Primer and Research Roadmap</title><link>http://pubsindex.trb.org/view/2672509</link><description><![CDATA[The frog is a component of special trackwork where one rail crosses another. Openings called flangeways in standard frogs let wheel flanges pass through. When a wheel passes through the flangeway at the frog point, contact between the wheel tread and frog wing rail creates high-impact forces, noise, and vibration. Low-impact frog designs can reduce these effects, but little public data exist on their effectiveness, longevity, or maintainability. This Transit Cooperative Research Program (TCRP) Research Report serves as a guide for transit agencies in selecting appropriate frog designs for noise and vibration mitigation and in maintaining effective noise and vibration performance through proper maintenance practices. It also offers a research roadmap for the rail transit community to focus its efforts to foster, support, monitor, disseminate, and implement research on frog system design.]]></description><pubDate>Thu, 26 Feb 2026 09:15:16 GMT</pubDate><guid>http://pubsindex.trb.org/view/2672509</guid></item><item><title>Design of Revenue Service Adjustments for Urban Rail System Maintenance</title><link>http://pubsindex.trb.org/view/2672021</link><description><![CDATA[Urban railway systems require regular maintenance to uphold safe and efficient operations. System operators are sometimes forced to perform this maintenance during revenue service hours. The resulting changes in revenue service are called a “revenue service adjustment,” or RSA. Because RSAs typically feature planning horizons of months or even years, operators have an opportunity to design them in ways that minimize the level-of-service (LOS) impacts for passengers. This paper presents a framework for operators to consider LOS impacts early in the RSA planning process. First, a taxonomy of service delivery strategies is developed, where various strategies can be characterized by typical LOS impacts and operational considerations to efficiently identify options to consider. Second, a method is presented to develop optimal service plans to deliver the various strategies. Third, the distribution of LOS impacts on various groups of passengers is found for each service plan. Finally, considerations related to work planning and productivity are quantified and balanced against LOS impacts. The framework is demonstrated on a real-world case study from the Washington Metropolitan Area Transit Authority (WMATA) in which a single track needed to be removed from service. The results show that under the same resource constraints, different RSA design decisions can result in a large range of potential wait time impacts, with ratios ranging from 1.15 to 1.34 compared with normal revenue service, as well as a promising daily time period to perform work that balances a large increase in productivity with a smaller increase in LOS impacts.]]></description><pubDate>Fri, 20 Feb 2026 15:28:56 GMT</pubDate><guid>http://pubsindex.trb.org/view/2672021</guid></item><item><title>Assessing Safety Effectiveness of Treatments and Technologies at Highway-Rail Grade Crossings</title><link>http://pubsindex.trb.org/view/2666565</link><description><![CDATA[This report provides information on the safety effectiveness of treatments and technologies at highway-rail grade crossings and presents a rational approach for evaluating this effectiveness, while considering different levels of data availability. The information contained in this report will help highway agencies and other organizations concerned with safety aspects at highway-rail grade crossings in making informed decisions regarding the deployment of treatments and technologies at such crossings to reduce incidents and improve safety.]]></description><pubDate>Sat, 07 Feb 2026 12:17:08 GMT</pubDate><guid>http://pubsindex.trb.org/view/2666565</guid></item></channel></rss>