<?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" 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>Empowering Electric Bus Deployment with Standardized Transit Data</title><link>http://pubsindex.trb.org/view/2689790</link><description><![CDATA[This study evaluates the accuracy of bus energy consumption estimates built on GPS data sampled at low frequencies and collected from standardized transit data feeds. It applies bus travel time forecast models to generate drive cycles for buses on any network reporting standardized data. An energy model is then applied to 33 international bus networks to assess the need to implement battery electric buses (BEBs). Previous work on this topic has focused on aggregating standardized bus GPS data directly to route segments. This study uses trained models to impute speed profiles for routes and networks without requiring the collection of network-specific data beyond that published in standard data feeds. This allows a wider-reaching comparison between agency electrification needs. Sensitivities are tested for key operational factors. Conclusions are then drawn on the adequacy of standardized bus data for energy analysis and practical findings across agencies. The findings suggest that low sampling frequency feed data do not significantly affect energy consumption estimates for BEBs, despite the challenges of modeling vehicle drive cycles. Current battery and charging technology is capable of supporting initial rollouts with unmanaged charging on low-energy scheduling blocks, but is incapable of supporting full electrification. To mitigate peak power costs and meet energy needs under full electrification scenarios, it is essential for agencies to adopt managed charging strategies.]]></description><pubDate>Thu, 09 Apr 2026 09:01:27 GMT</pubDate><guid>http://pubsindex.trb.org/view/2689790</guid></item><item><title>Evaluation of Foamed Glass Aggregate for Roadway Embankment Applications</title><link>http://pubsindex.trb.org/view/2689791</link><description><![CDATA[Lightweight fill materials play critical roles in building infrastructure on challenging sites. Foamed glass aggregate (FGA) is a lightweight option that has attracted much attention lately. FGA is a processed recycled aggregate made from waste glass. The process involves grinding the glass into powder and melting it at a high temperature (e.g., 1,600°F) with a foaming agent (e.g., 2% by weight). In addition to its low compacted unit weight, FGA possesses several unique engineering properties, such as a high friction angle, good thermal insulation, high permeability, easy placement, and so forth. With these properties, the utilization of FGA could be a sustainable practice that contributes to the reduction of fill settlement over soft ground and environmental preservation by the reuse of waste glass. However, as with any emerging or unconventional material, a comprehensive engineering study of FGA is essential before its widespread application to prevent unsatisfactory performance. To that end, two types of FGA material (produced using either a dry or wet foaming agent) and two conventional soils (sand and clay, used as references) were procured for laboratory experiments. These experiments covered basic FGA characteristics, including gradation and volumetric properties, followed by mechanical properties such as axial compression compaction, one-dimensional consolidation, dynamic triaxial, and direct shear. In addition, a pilot fill construction was undertaken using FGA to determine the field compaction acceptance criteria. Results indicated that FGAs are viable lightweight fill materials. Further research is needed to monitor FGA performance through full-scale construction projects.]]></description><pubDate>Thu, 09 Apr 2026 09:01:27 GMT</pubDate><guid>http://pubsindex.trb.org/view/2689791</guid></item><item><title>Study of Risk Allocation Mechanism for Transportation Public–Private Partnership Projects Considering the Risk Tolerance of Participants</title><link>http://pubsindex.trb.org/view/2689788</link><description><![CDATA[Adequate risk allocation demands consideration of the participants’ risk tolerance. Without prompt risk reallocation, public–private partnership (PPP) transportation projects may fail when project risks exceed the participants’ risk tolerance. This paper establishes a dynamic risk allocation mechanism for PPP transportation projects from the perspective of participants’ risk tolerance, to ensure smooth operation. This paper employs bargaining and evolutionary game theory to construct a risk allocation mechanism. It includes risk allocation and reallocation, and risk allocation schemes and strategies for the two stages are obtained by solving the game model. The research findings indicate three risk overspending scenarios following the risk allocation. When one party exceeds the risk tolerance, the evolutionary stability strategy tends to assist the overspending party in bearing the risk if the other party has not overspent. When both parties exceed their risk tolerance, the evolutionary stability strategy tends to share the risk. The willingness of participants to engage in risk reallocation can be improved by boosting the participants’ risk preference. Under the same conditions, the risk preference of private investors is more sensitive to the willingness to participate in risk reallocation than that of the government. The proposed dynamic risk allocation mechanism comprehensively links risk allocation and reallocation, thereby resolving the issue of participants exceeding their risk tolerance. It enhances risk allocation efficiency and risk management level, thus ensuring the stable implementation of transportation PPP projects.]]></description><pubDate>Thu, 09 Apr 2026 09:01:27 GMT</pubDate><guid>http://pubsindex.trb.org/view/2689788</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>Business Ethics in Ship Agencies</title><link>http://pubsindex.trb.org/view/2688831</link><description><![CDATA[Increasing operational pressures and demands for corporate transparency in the maritime sector highlight the need to reassess the dynamics shaping business ethics in ship agencies. This study aims to systematically identify the factors shaping the ethical structure in ship agencies and their mechanisms of influence by analyzing these dynamics using a multidimensional approach. In the research, eight fundamental ethical factors identified through a literature review were quantitatively analyzed using the DEMATEL method in line with expert opinions; the causal structures obtained with DEMATEL were compared with the findings of the thematic content analysis conducted on 80 keywords using MAXQDA. DEMATEL findings indicate that Work Pressure, Corporate Trust, and Social Responsibility are positioned as influencing factors with high causal power within the system; while Corporate Values and Company Image emerge as affected outcome variables with high levels of dependence and centrality. There was a notable overlap between the findings of the thematic content analysis conducted using DEMATEL and MAXQDA. In particular, a bidirectional, intense, and stable network of interactions was identified between Corporate Values and Company Image. However, for example, while the Work Pressure factor had high directive power in the DEMATEL analysis, it showed relatively lower conceptual visibility in the MAXQDA content analysis, indicating a mismatch between the emphases of the two methods. The findings reveal that, in addition to corporate values and reputation management, reducing operational pressures and strengthening corporate trust mechanisms should be addressed as fundamental strategic priorities for an ethical and sustainable business model in ship agencies.]]></description><pubDate>Sat, 04 Apr 2026 10:52:04 GMT</pubDate><guid>http://pubsindex.trb.org/view/2688831</guid></item><item><title>Determination of Pavement Distress Severity Using Machine Learning: Systematic Review</title><link>http://pubsindex.trb.org/view/2688830</link><description><![CDATA[Artificial intelligence techniques have advanced significantly in recent years and can be applied across various fields of knowledge. In civil engineering, such techniques as machine learning and computer vision have proven useful in pavement inspection and evaluation—processes that are traditionally carried out manually in the field, demanding considerable time and effort from inspectors. To address the limitations of manual inspections, numerous studies have aimed to automate this process by employing algorithms capable of recognizing and classifying surface distress. However, few studies address these algorithms’ ability to determine the severity level of pavement distress, a crucial piece of information for planning maintenance and rehabilitation activities. Therefore, the aim of this study is to conduct a systematic literature review, using the systematic search flow method, of research that employed machine learning techniques to automatically or semi-automatically determine the severity levels of pavement distresses. A search conducted in two databases (Scopus and Web of Science) yielded a total of 283 articles. After applying a defined filtering process, 28 studies were identified as meeting the established scope. A review of these articles revealed that machine learning is an effective method for distress recognition and severity classification. Nonetheless, owing to the limited exploration of this topic in the current literature, further investigation and detailed analysis of specific elements are necessary in future studies.]]></description><pubDate>Sat, 04 Apr 2026 10:52:04 GMT</pubDate><guid>http://pubsindex.trb.org/view/2688830</guid></item><item><title>Simplified Method for Structural Capacity and Reinforcement Design of Reinforced Concrete Circular Bridge Piers Considering Second-Order Effects</title><link>http://pubsindex.trb.org/view/2686651</link><description><![CDATA[The traditional calculation methods for the second-order structural capacity and reinforcement of reinforced concrete circular slender piers have certain limitations. The traditional calculation process involves many complex formulas and iterative calculations, which are difficult to complete manually and bring many inconveniences to practical engineering applications. To address this challenge, this article establishes five strain zones based on the complete constitutive relationship curves of concrete and reinforcement, solves the internal forces with strain as the independent variable, avoids the iterative calculation of the traditional standard methods, derives the calculation formula for the structural capacity of reinforced concrete circular sections, and provides a dimensionless chart for determining the structural capacity and reinforcement of circular section piers and columns. Based on this, a calculation method for calculating the second-order structural capacity and reinforcement of reinforced concrete circular section piers is provided. This method significantly simplifies the second-order structural capacity and reinforcement calculation process of reinforced concrete circular bridge piers, making up for the shortcomings of determining numerous calculation parameters and iteratively solving transcendental equations in the traditional standard calculations, and providing a convenient and efficient manual calculation tool for engineering practice. The calculation results of the examples demonstrate that the proposed method enables simple and rapid determination of the second-order structural capacity and reinforcement for reinforced concrete circular slender piers using the reinforcement with a characteristic yield strength of 500 MPa, showing good agreement with traditional standard iterative calculation methods and exhibiting good accuracy and reliability.]]></description><pubDate>Fri, 03 Apr 2026 10:06:10 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686651</guid></item><item><title>Commoning Cycling: Grassroot Initiatives for Inclusive Mobility Transitions Among People Facing Barriers to Cycling</title><link>http://pubsindex.trb.org/view/2686281</link><description><![CDATA[Improving the conditions for sustainable mobilities is the focus of considerable political and public attention. This paper identifies various ways that civil society initiatives promote cycling inclusion for marginalized groups facing barriers to cycling. An emphasis on commoning of cycling and cycling inclusion highlights how grassroot initiatives and their “commoners” take action to achieve an ambition to make cycling more inclusive in a bottom-up approach. In total, 12 initiatives have been studied, broadly categorized as bike kitchens, bike schools, bike to school, and bike promotion initiatives, located in Belgium, Greece, Italy, Portugal, Romania, and Sweden, respectively. These initiatives address groups that experience marginalization in the current mobility system (i.e., women with immigrant background, children, people with disabilities, seniors), and promote cycling through various forms of learning activities and skills to lower the thresholds to cycling and making cycling more diversified. The paper takes a holistic approach to shed light on the various ways that grassroot initiatives promote cycling inclusion, and, based on the experiences of participants and facilitators, explores what such initiatives may achieve given differences in context and target groups. While the results show that cycling was mainly available for those participants that managed to adjust to the presumed norm of the confident, able-bodied, and individualized mobile subject, the initiatives had unexpected impacts on social dynamics of relevance to social justice. The results show the importance for cycling policy and planning to support concrete actions to improve the conditions for cycling to realize the full potential of cycling in the green transition.]]></description><pubDate>Fri, 03 Apr 2026 10:06:10 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686281</guid></item><item><title>Exploring Cross-Organizational Innovation Cooperation in China’s Transport Sector: Insights from Science and Technology Awards</title><link>http://pubsindex.trb.org/view/2686280</link><description><![CDATA[Science and technology innovation is key to implementing China’s “Strong Transportation Nation” strategy. Cross-organizational innovation cooperation fosters high-quality innovation. Based on data from China’s Science and Technology Awards between 2002 and 2020, this study analyzes the innovation cooperation network within China’s transportation sector and its impact pathways on innovation performance. Employing social network analysis, the research analyzes the network architecture, node characteristics, and regional disparities of innovation collaborations, thereby revealing the structural patterns and evolutionary trends of these partnerships in the Chinese transportation sector. Furthermore, the study applies fuzzy-set qualitative comparative analysis to assess the impact of network features on innovation performance. By integrating factors of network structure, node attributes, and the external environment from a configurational perspective, this approach identifies multiple equifinal pathways that lead to high innovation performance. The results indicate that both the network scale and number of relationships have shown continuous growth. The network exhibits small-world properties, meaning that any two entities can be connected through up to three nodes. Enterprises are the prominent leaders in the network, while the involvement of research institutions is weakening. Innovation subjects located at core nodes tend to stabilize, and their control capacity gradually increases. Both intra-regional and inter-regional cooperation have become more complex. High levels of intra-regional cooperation are observed in both economically advanced regions and underdeveloped regions. Inter-regional cooperation centers on Beijing and radiates across the country. The highest cooperation densities are concentrated in the Beijing-Tianjin-Hebei, Chengdu-Chongqing, and Pearl River Delta regions. Regions such as Xizang, Qinghai, and Ningxia play a very limited role within the inter-regional innovation cooperation network. Network embeddedness, especially network centrality, has a broader impact on innovation cooperation performance than either node attributes or external context. High innovation cooperation performance is driven by two distinct paths: the individual capability-driven path and the individual-environment alignment path, while low performance stems from limited innovation and economic capacity, together with weak network connectivity.]]></description><pubDate>Fri, 03 Apr 2026 10:06:10 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686280</guid></item><item><title>Cooperative Adaptive Cruise Control with Model-Based Imitation Reinforcement Learning in Mixed Traffic of Connected Autonomous and Human Driven Vehicles</title><link>http://pubsindex.trb.org/view/2686278</link><description><![CDATA[Cooperative adaptive cruise control (CACC) can improve the traffic efficiency and safety of a platoon on the road. Most traditional CACC methods need to rely on accurate mathematical models, while those based on deep reinforcement learning (DRL) suffer from long training times and poor convergence. In this context, this study proposes a CACC framework based on imitation learning (IL) and DRL, which aims to improve the car-following efficiency and long platoon stability of connected autonomous vehicles (CAVs) in a mixed traffic environment. This method combines the optimization ability of model predictive control (MPC) and the adaptive learning characteristics of a soft actor-critic (SAC) algorithm. MPC is demonstrated as an expert, and the pre-training policy network is obtained by imitation learning. The pre-training network is then introduced into SAC’s actor network, which enhances training efficiency in the SAC algorithm. Numerical simulation results show that the improved DRL algorithm has better convergence in the training process. Compared with the baseline model, the proposed framework has higher reward, lower tracking error, and better platoon stability in the evaluation. In addition, the proposed model can efficiently complete the task of car-following under different penetration rates.]]></description><pubDate>Fri, 03 Apr 2026 10:06:10 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686278</guid></item><item><title>The Effects of Curb Extensions on Traffic Crashes and Injuries</title><link>http://pubsindex.trb.org/view/2688680</link><description><![CDATA[This paper employs Bayesian negative binomial models to examine the effects of curb extensions on traffic safety through their implementation as part of a stormwater management program in the City of Philadelphia. Although widely deployed to promote traffic safety, the effects of curb extensions on traffic safety are poorly understood. Between 2011 and 2023, the Philadelphia Water Department installed 156 vegetated curb extensions that protruded into the street and initiated the design of 342 curb extensions to be built by 2029. Although pre-existing crash data featured in the selection of treated locations, the focus on stormwater management and long list of treated and untreated intersections provide unique, quasi-experimental conditions under which to examine the effects of curb extensions. After matching these curb extensions to intersections and removing midblock interventions, we created a dataset of 94 treated intersections and 269 control intersections installed between 2013 and 2023. Each intersection included a single curb extension. We matched these spatially to annually aggregated crash data from 2012 to 2024. We also matched these to data on the roadway width, roadway class, signalization at the intersection, and expected acres of drainage associated with stormwater management. Analysis suggested that curb extensions reduced the incidence of reported crashes by around 13% at a typical intersection. However, the 95% credible interval ranged from a 35% decrease to an 18% increase. Findings suggest that a single curb extension may reduce collisions and injuries but that additional studies are needed from fully treated intersections.]]></description><pubDate>Thu, 02 Apr 2026 16:17:57 GMT</pubDate><guid>http://pubsindex.trb.org/view/2688680</guid></item><item><title>Modal Split and Bus Fare Allocation for a Congested Bottleneck: Autonomous Vehicles and Buses</title><link>http://pubsindex.trb.org/view/2686658</link><description><![CDATA[With the goal of reducing traffic congestion for urban commuters, and in alignment with the global shift toward smarter, more sustainable, and more equitable cities, the transportation field is faced with the challenge of improving and optimizing its systems. This paper will tackle the morning commute problem of a congested bottleneck shared between buses and autonomous vehicles (AVs). The objective of this study is to determine the optimal bus fare, departure time, and mode split simultaneously by minimizing the total system social travel cost using numerical techniques. In addition, the paper examines the sensitivity of the system social cost to parameters such as bus capacity and frequency. Using a simple numerical example, the relationships between mode split, bus fare, total cost of a bus trip, dispatching frequency, bus capacity, total cost of an AV trip, and AV fare to the system social cost are examined, and optimal values are presented and discussed. The distribution of trips and the influence of AV capacity are also explored. The findings suggest that, within a reasonable range, the optimal bus fare was the absolute minimum, and the optimal mode split was one with fewer bus passengers but no boundary value. Other interesting findings were observed assuming a predetermined and fixed bus fare. Overall, the methodology and results of this research paper offer valuable insights for traffic and transit authorities, which could aid in planning and operational decisions that ultimately reduce commuter delays and enhance the sustainability of the morning commute.]]></description><pubDate>Thu, 02 Apr 2026 15:23:59 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686658</guid></item><item><title>Development and Validation of a New Dielectric Profiling System Dielectric–Density Calibration Model Using Laboratory and Field Data</title><link>http://pubsindex.trb.org/view/2686656</link><description><![CDATA[Achieving reliable dielectric–density calibration is critical for accurate asphalt pavement compaction assessment using the dielectric profiling system (DPS). This study introduces and evaluates the average Hashin–Shtrikman (Ave-HS) model, or dielectric mixing model, designed to generate robust calibrations with minimal data. DPS measurements, field cores, and superpave gyratory compacted (SGC) specimens (pucks) from 22 projects in Michigan (29 datasets) were analyzed to assess model accuracy, variability, and bias. Puck-based calibrations were highly consistent: 28 of 29 datasets showed standard deviations below 0.5% voids, and as few as two pucks compacted in the laboratory provided reliable calibration results. Core-based calibrations exhibited greater variability, with over half of the datasets exceeding 1.0% voids standard deviation and several surpassing the ±1.25% measurement-to-measurement variability threshold. Day-to-day variability was minimal in both pucks and cores (≈0.4% voids), showing that calibrations remain stable across different asphalt mix production days under consistent mix conditions, allowing a single puck calibration to be applied over multiple paving days without repeated daily calibrations. Core–puck comparisons showed agreement within 2% voids for 23 of 29 datasets. Outlier datasets generally exhibited higher-than-expected core dielectrics, suggesting residual surface moisture at the time of DPS testing. Forensic re-testing of discrepant cores in the laboratory aligned with puck-based calibrations, further supporting the conclusion that field moisture influenced the initial measurements. The Ave-HS model’s physics-based approach, combined with minimal sampling requirements, provides a practical calibration method for DPS deployment. Puck-derived calibrations are recommended as the primary reference, with core measurements used for verification and forensic evaluation when discrepancies arise.]]></description><pubDate>Thu, 02 Apr 2026 15:23:59 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686656</guid></item><item><title>Evaluation of Machine Learning and Deep Learning Models for Multi-Horizon Crowd Forecasting at Scheveningen Beach, The Netherlands</title><link>http://pubsindex.trb.org/view/2686655</link><description><![CDATA[Efficient crowd management is crucial for municipalities to ensure public safety and enhance visitor experience, particularly in tourist-centric areas, such as Scheveningen Beach. Scheveningen Beach faces challenges because of the limited precision of visitor count data and the lack of accurate forecasts. Currently, crowd safety managers use their professional experience to forecast based on factors such as weather, events, and holidays, leading to inaccuracies, highlighting the need for accessible data and advanced analytics to enhance crowd management strategies. This study evaluates machine learning and deep learning models for multi-horizon hourly pedestrian crowd count forecasting, addressing the limitations of current manual prediction methods. Historical crowd data, weather, and holidays were integrated to train eXtreme gradient boosting, categorical boosting (CatBoost), light gradient boosting machine (LightGBM), long short-term memory (LSTM), and Temporal Fusion Transformer models for short-term (1-day), mid-term (7-day), and long-term (30-day) horizons. Models were developed for individual locations and as a unified multilocation approach. Performance was assessed using the coefficient of determination, root mean square error, normalized root mean square error, symmetric mean absolute percentage error, mean absolute error, and normalized mean absolute error metrics. The results showed that CatBoost was best for short-term forecasts, CatBoost and LightGBM for mid-term forecasts, and LSTM and LightGBM for long-term forecasts. Forecast performance decreases over longer time horizons in many locations, suggesting different applications: short-term forecasts for immediate operational decisions and long-term predictions for general trend analysis and strategic planning. Individual location models generally outperformed the unified approach, but at a higher computational cost. This study reveals significant spatial and temporal variability in crowd dynamics, which is crucial for optimizing resource allocation and enhancing preparedness in crowd management at Scheveningen Beach and similar tourist destinations.]]></description><pubDate>Thu, 02 Apr 2026 15:23:59 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686655</guid></item><item><title>Lane Change Trajectory-Tracking Control Strategy of Superhighway</title><link>http://pubsindex.trb.org/view/2686653</link><description><![CDATA[To improve the operation efficiency of the superhighway and to ensure its driving safety, this paper comprehensively uses the methods of theoretical modeling and simulation analysis to explore the trajectory planning and collision avoidance control model of the superhighway. Considering vehicle dynamics constraints and surrounding vehicle constraints, a yaw rate model and a lane change duration boundary model are established to generate a safe and feasible lane change trajectory. The collision avoidance conditions of static obstacles and dynamic obstacles are divided, and the triggering conditions of braking priority and lane change priority are determined based on the braking collision avoidance distance, so as to improve the collision avoidance ability of the vehicle under different driving conditions. An adaptive model predictive control algorithm is designed to realize the tracking control of the vehicle lane-changing trajectory. The CarSim/Simulink cosimulation model was built, and three sets of simulation scenarios were designed based on the superhighway static and dynamic obstacle lane-changing collision avoidance. The effectiveness of the trajectory-tracking control model is verified by the vehicle dynamic parameters and trajectory-tracking accuracy.]]></description><pubDate>Thu, 02 Apr 2026 15:23:59 GMT</pubDate><guid>http://pubsindex.trb.org/view/2686653</guid></item></channel></rss>