The U-shaped rib-to-deck welded joint in orthotropic steel decks (OSDs) is prone to multiple fatigue cracks, which threaten structural integrity. Current design codes worldwide stipulate a minimum weld penetration rate of 75% or 80%, but practical challenges exist in meeting these requirements due to welding process limitations and machining errors. This study aims to investigate the influence of weld penetration rate on the fatigue performance of such joints, providing a theoretical basis for optimizing design and construction schemes.

Firstly, finite element models of U-shaped rib-to-deck welded joints with penetration rates of 65%, 75%, 85% and double-sided welds were established to analyze mechanical characteristics under typical loading conditions. Fatigue tests were then conducted on specimens with different penetration rates, and phased array ultrasonic testing technology was employed to assess penetration depth. Finally, fatigue S-N curves were regressed for partial penetration and double-side welded joints to quantify fatigue performance.

Stress concentration at the weld root decreases with the increase of penetration rate in partial penetration welds, while double-sided welds eliminate the weld root and further reduce stress concentration. Penetration depth exhibits significant dispersion even within the same weld. Partial penetration welds mainly initiate cracks from the weld root and propagate along the weld throat, whereas double-sided welds initiate cracks from the inner weld toe and propagate along the rib web. The fatigue strength of double-sided welds (143.9 MPa) is significantly superior to that of partial penetration welds (96.9 MPa) at 2×106 cycles.

This study fills the gap of limited experimental data on the fatigue performance difference between partial penetration and double-side rib-to-deck welded joints. The findings clarify the influence mechanism of penetration rate on fatigue behavior, providing valuable theoretical support and technical reference for the design optimization, construction quality control and maintenance decision-making of OSD welded joints.

In recent years, the rapid advancement of artificial intelligence (AI) has exerted profound impacts on and provided strong impetus to numerous fields in the industrial sector. Within the railway industry, AI has driven continuous upgrading and optimization of intelligent train control technology, thanks to its enhanced computational capabilities derived from advanced algorithms and models, as well as its role in improving safety performance. Integrating AI technology more extensively into train autonomous driving and control has thus become an inevitable trend in the global development of railways.

This paper, therefore, conducts a comprehensive analysis of the development progress and current status of AI technology applications in the field of train driving and control on a global scale. It systematically sorts out and analyzes the advantages of various AI technologies and the positive impacts they bring to the upgrading of train control technology, elucidates the feasibility and future prospects of applying a range of emerging AI technologies from the perspective of technical theory and provides guidance for the intelligent development of this field from a practical perspective.

The application of AI technology in the train driving and control field is still in its infancy. While a large number of AI technologies have been widely adopted, there remains significant room for further optimization and improvement of these technologies. Additionally, a variety of AI technologies that have been applied in other industrial sectors but not yet widely implemented in training autonomous driving and control have demonstrated tremendous development potential.

The research findings provide references and guidance for advancing train control technology, promoting the digital transformation of railways, accelerating the overall optimization and upgrading of railway industry technologies, and facilitating the accelerated development of global railways.

This study systematically examines the potential for integrating crowd logistics (CL) with rail transport to enhance the efficiency, sustainability and multimodal performance of first and last-mile urban freight operations. It synthesizes the conceptual and empirical foundations of this emerging research area, identifies dominant scholarly trends and highlights gaps that constrain practical implementation of Rail-CL systems.

A systematic literature review was conducted following PRISMA 2020 guidelines. Fifty peer-reviewed publications from 2009 to 2025 were selected from major academic databases and evaluated using the 2018 Mixed Methods Appraisal Tool (MMAT). Extracted data covered study design, research aims, geographic scope, transport modes, technologies, sustainability outcomes, integration strategies and reported barriers. The evidence was synthesized using thematic and descriptive analysis.

The literature reveals a strong bias toward last-mile crowdshipping, with comparatively limited attention to first-mile operations and rail-based multimodal integration. Although environmental, economic and social benefits are frequently reported, most studies remain conceptual with limited real-world validation. Core challenges include regulatory uncertainty, inadequate rail-terminal infrastructure, coordination difficulties among stakeholders and persistent concerns regarding trust, liability and service reliability. Only a small number of studies propose integrated Rail and CL frameworks, confirming a substantial research gap.

This review offers the first comprehensive assessment of literature directly linking CL with rail freight transport. It establishes Rail and CL integration as an emerging research domain and outlines a forward-looking agenda focused on empirical testing, digital platform development and context-specific models particularly relevant for developing countries pursuing sustainable and resilient freight systems.

Association of American railroads (AAR) standard automatic couplers are designed for much higher capacity than the normal operating loads. However, failure of knuckles and coupler bodies is still a common occurrence. Recent studies have shown that fatigue is the main reason behind such failures below the expected load. Moreover, knuckle failures occur more frequently than coupler body failures, which cause operational disruptions and also influence overall coupler life because of nonconforming contact between a new knuckle and an old coupler. In addition to new and old counterparts, undesired contact conditions are often the case with the new assembly due to casting-based manufacturing inaccuracies.

A study is thus carried out in this paper to understand the variation of load transfer paths and its consequences caused by dimensional variability. A finite element model of an E-type coupler’s knuckle is developed and different possible contact conditions of the knuckle with the coupler head are simulated. Knuckles generally fail in pulling mode, during which the possible contacting elements of knuckle are pulling lugs, pin protector regions and pinholes. Due to dimensional variability, contact conditions may exist where an individual or a combination of these elements are in contact.

Simulation results indicate that under regular operational conditions, having only the pulling lugs in contact reduces the risk of knuckle failure and maintains assembly integrity even if the knuckle fails. However, under extreme loading conditions, the safest scenario is when both pulling lugs and pin protector regions are in contact.

These findings are believed to assist in defining the dimensional variability limits to ensure the desired contacts between the mating surfaces of the knuckle and coupler body of railway couplers of AAR type. This work contributes to understanding implications of dimensional variability in the railway couplers. The insight presented are useful in design, manufacturing and maintenance of railway coupler’s knuckle.

The pantograph-catenary system (PCS) plays a crucial role in ensuring stable and continuous current collection in electric railway operations. This paper aims to review and synthesize existing research on contact strip (CS) wear, with particular emphasis on dominant wear mechanisms, influencing parameters, and material performance under high-speed train (HST) conditions.

A structured and critical review of the literature is conducted, covering mechanical, electrical, and electro-mechanical wear mechanisms. Relevant studies are analysed in terms of operating conditions, including train speed, contact force, electrical current intensity, system configuration and environmental influences. Special attention is given to metal-impregnated carbon materials, which are widely adopted in current HST applications, as well as to composite materials that are being actively investigated and developed for future HST systems. Comparative analysis is performed to identify governing factors and methodological trends in existing investigations.

The literature indicates that CS degradation results from strongly coupled mechanical and electrical loading, with the relative contribution of each wear mechanism varying according to operating regimes and material characteristics. Carbon-based composite materials demonstrate a favourable balance between conductivity, wear resistance and compatibility with the contact line (CL). However, inconsistencies remain in the quantification of wear interactions and in the standardisation of evaluation approaches under diverse climatic and operational conditions.

This review provides an integrated and up-to-date synthesis of multi-mechanism wear behaviour in CS, highlighting current research gaps and methodological limitations. The paper offers structured insight to support material selection, performance optimisation and future research directions, contributing to enhanced reliability and maintenance efficiency of HST systems.

The expansion of the railway network and the increase in operation and maintenance intensity have rendered the durability, applicability and standardization of bridge guardrails key bottlenecks for ensuring personnel safety, improving the efficiency of maintenance windows, reducing the full life cycle cost, and promoting the high-quality development of railways. It is urgent to systematically sort out the domestic technological evolution, quantitatively evaluate the material performance, establish a full life cycle management framework, fill the gaps in the current standards regarding material selection, manufacturing and acceptance, and provide a scientific basis for the formulation of new standards.

(1) Literature and case study research - summarize the application characteristics and failure modes of steel, concrete, and fiber composite materials. (2) Material and process testing - measure the mechanical, corrosion resistance, and aging resistance properties of polyurethane pultruded composite materials. (3) Structural calculation - check the displacement of each railing post and handrail, and verify the safety margin. (4) Standard comparison - identify the gaps between domestic and international standards and the improvement paths.

Polyurethane railings are lightweight, high-strength, weather-resistant, maintenance-free, have minimal deformation and are suitable for coastal and cold regions. Steel railings corrode rapidly, are costly to repaint, and are difficult to maintain. Concrete is prone to cracking, frost peeling and rust expansion, and has a short lifespan. The current standards lack durability indicators, process control and full-life cycle evaluation, which restricts the promotion of new materials.

Establish polyurethane as the preferred option in complex environments; offer optimization directions for steel and concrete anti-corrosion structures; supplement durability indicators, process key points and cost models, and promote the standardization, lightweighting and long service life of ancillary facilities.

The study aims to analyze the relationship between seismic damage to various railway infrastructures and seismic intensity through historical seismic damage investigations of conventional railways, thereby addressing the issues of a lack of focus in post-earthquake inspections and prolonged train service restoration times after seismic events.

Post-earthquake railway inspection data were collected from 6 historical earthquakes in Xinjiang and 4 in the Sichuan-Yunnan region through field surveys and data research. Longitude and latitude coordinates of damaged sections were calculated according to their kilometer markers (K marks) and visualized on maps. The approximate seismic intensity at each damage site was estimated using intensity attenuation relationships or instrumental intensity data from adjacent stations, and empirical patterns of seismic damage modes were summarized.

Through investigations of historical seismic data and actual railway damage in Xinjiang and the Sichuan-Yunnan region, results indicate that in areas with seismic intensity greater than Level V (I > V), main structural damage to conventional railway infrastructure occurs. This includes cracking of bridge piers and abutments, differential settlement at bridge ends, track distortion, fracture of tunnel portals, and edge collapse, all of which disrupt train operations. In contrast, in areas with seismic intensity of Level Vor below (I 5 V), no records indicate that earthquakes caused main structural damage to conventional railway infrastructure. Only damage to ancillary facilities was observed, such as concrete spalling from girders, cracking of transverse diaphragms, damaged protective cones, deformed limiters, and cracks in subgrade slopes—none of which affect train passage.

Based on investigations into the post-earthquake infrastructure conditions of conventional-speed railways in earthquake-prone regions of China such as Xinjiang, Sichuan and Yunnan after 10 historical earthquakes, this study analyzed the correlation between seismic damage and corresponding seismic intensities using instrumental intensity data from surrounding seismic stations and intensity attenuation laws. A conclusion was drawn that train operation remains unaffected in areas with seismic intensity no higher than V (I 5 V). For the first time, this research established a correlation between post-earthquake damage to conventional-speed railways and seismic intensity, and identified the safety threshold at seismic intensity V. The findings enable railway personnel to conduct targeted post-earthquake inspections, significantly reduce inspection workload, and alleviate the pressure on post-earthquake operation recovery.

There are significant differences in the corrosion protection performance of commonly used cleaning agents for high-speed railways. In order to study the dual requirements of cleaning efficiency and corrosion inhibition, explore the differences in corrosion protection performance of cleaning agents, effectively protect metal substrates, and ensure the safe, economical, and environmentally friendly operation of high-speed railways, this study is hereby carried out.

This study investigated the corrosion behaviour of Q235 steel exposed to acidic, neutral, and alkaline cleaning agents through metallographic analysis, electrochemical testing, and scanning electron microscopy (SEM).

Electrochemical behaviour was assessed at concentrations of 5%, 10%, 15%, and 20% using electrochemical impedance spectroscopy (EIS) and Tafel tests. The results indicate that the protective efficacy of acidic, neutral, and alkaline cleaning agents follows the order: alkaline > neutral > acidic.

Microstructural analysis and energy-dispersive X-ray spectroscopy (EDS) surface element quantification reveal that acidic cleaning agents cause the most severe corrosion and offer the poorest protection for Q235 steel, whereas neutral and alkaline agents provide protective effects by retarding corrosion. Conducting in-depth research on the differences in corrosion protection performance of cleaning agents can effectively safeguard metal substrates, eliminate corrosion risks, and ensure the safe operation of high-speed railways.

The purpose of this study is to examine the determinants of modal shift intention from road freight transport to rail freight in Morocco, focusing on the perceived economic, energy and environmental performance of rail freight.

A quantitative survey was conducted among key freight transport stakeholders, including road carriers, industrial shippers, logistics operators and experts. A total of 483 valid questionnaires were collected. Measurement scales were derived from the literature and adapted to the Moroccan context. Data were analyzed using SPSS through descriptive statistics, reliability analysis, correlation tests and multiple linear regression.

The results indicate generally positive perceptions of rail freight, particularly regarding energy efficiency and environmental performance. All three perceived performance dimensions have a positive and significant effect on modal shift intention. Perceived energy performance emerges as the strongest predictor, followed by environmental impact, while economic performance shows a significant but more moderate influence. The model demonstrates strong explanatory power. Research limitations/implications – The study relies on perceptual data and a non-probabilistic sampling approach, which may limit the generalizability of the findings. Future research could integrate objective cost, energy and emission data; apply longitudinal designs or extend the model by incorporating institutional, infrastructural and policy-related variables to further explain rail freight adoption. Practical implications – The findings provide valuable insights for policymakers, rail operators and logistics managers by highlighting the key levers for promoting rail freight development. Strengthening rail energy efficiency, improving service reliability and enhancing intermodal integration can significantly increase stakeholders’ willingness to shift freight from road to rail. Social implications – By encouraging modal shift toward rail freight, the study supports broader societal objectives related to environmental protection, energy security and sustainable development. Increased use of rail freight can contribute to reduced greenhouse gas emissions, lower road congestion and improved quality of life in urban and industrial areas.

This study provides one of the first empirical investigations of rail freight modal shift determinants in Morocco, offering an integrated analysis of economic, energy and environmental factors within a single conceptual framework.

High-speed railway development in Vietnam requires an early assessment of wheel-rail degradation mechanisms. This study investigates wheel wear evolution and rolling contact fatigue (RCF) risk under representative high-speed operating conditions.

A numerical framework integrating multibody vehicle dynamics and wear prediction modelling is developed. Vehicle-track interaction is simulated in VI-Rail using a standard ERRI passenger bogie model. Key wheel-rail contact parameters, including normal forces, creepages and contact locations, are extracted and used in an Archard-based wear model to predict wheel profile evolution, while RCF risk is assessed using Hertzian contact stress indicators.

The results show that wheel wear alters tread geometry, with a maximum wear depth of approximately 0.2–0.4 mm, affecting vehicle dynamics. The critical speed varies non-monotonically, increasing by about 3–5% at early stages and decreasing by 10–15% with further wear. Track irregularities raise creepage to the order of 10?³ and increase wear rate by 20–30%. These effects also indicate an elevated risk of RCF.

The study provides a multibody dynamics-based framework for analysing wheel wear and RCF in prospective Vietnamese high-speed railway applications. The proposed framework also provides a scientific basis for assessing wheel degradation and supporting infrastructure design, operational planning and predictive maintenance in high-speed railway systems.