The precast concrete slab track (PST) has advantages of fewer maintenance frequencies, better smooth rides and structural stability, which has been widely applied in urban rail transit. Precise positioning of precast concrete slab (PCS) is vital for keeping the initial track regularity. However, the cast-in-place process of the self-compacting concrete (SCC) filling layer generally causes a large deformation of PCS due to the water-hammer effect of flowing SCC, even cracking of PCS. Currently, the buoyancy characteristic and influencing factors of PCS during the SCC casting process have not been thoroughly studied in urban rail transit.

In this work, a Computational Fluid Dynamics (CFD) model is established to calculate the buoyancy of PCS caused by the flowing SCC. The main influencing factors, including the inlet speed and flowability of SCC, have been analyzed and discussed. A new structural optimization scheme has been proposed for PST to reduce the buoyancy caused by the flowing SCC.

The simulation and field test results showed that the buoyancy and deformation of PCS decreased obviously after adopting the new scheme.

The findings of this study can provide guidance for the control of the deformation of PCS during the SCC construction process.

The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.

A high-speed railway subgrade settlement interval prediction method using the secretary bird optimization (SBOA) algorithm to optimize the BP neural network under the premise of gray relational analysis is proposed.

Using the SBOA algorithm to optimize the BP neural network, the optimal weights and thresholds are obtained, and the best parameter prediction model is combined. The data were collected from the sensors deployed through the subgrade settlement monitoring system, and the gray relational analysis is used to verify that all four influencing factors had a great correlation to the subgrade settlement, and the collected data are verified using the model.

The experimental results show that the SBOA-BP model has higher prediction accuracy than the BP model, and the SBOA-BP model has a wider range of prediction intervals for a given confidence level, which can provide higher guiding value for practical engineering applications.

This study is dedicated to systematically collating the distribution and utilization circumstances of geothermal resources in China. Moreover, it endeavors to formulate a comprehensive utilization scheme for geothermal resources during the construction and operation phases of the railway, thereby furnishing robust support and valuable reference for the holistic utilization of geothermal resources along the railway corridor.

Through an in-depth analysis of the extant utilization of geothermal resources in China, it is discerned that the current utilization modalities are relatively rudimentary, bereft of rational planning and characterized by a low utilization rate. Concurrently, by integrating the practical requisites of railway construction and operation and conducting theoretical dissections, a comprehensive utilization plan for the construction and operation periods of railway is proffered.

In light of the railway's construction and operation characteristics, geothermal utilization models are categorized. During construction, comprehensive modalities include tunnel illumination power generation, construction area heating, tunnel antifreeze using shallow geothermal energy, tunnel pavement antifreeze and construction concrete maintenance. During operation, they comprise operation tunnel antifreeze, railway roadbed antifreeze, railway switch snow melting and deicing, geothermal power station establishment and railway hot spring health tourism planning.

According to the characteristics and actual needs of railway construction and operation, it is of great significance to rationally utilize geothermal resources to promote the construction and operation of green railways.

This study summarizes the overall situation of the resources of the national science and technology innovation platform in the railway industry, including the distribution of platform types, supporting institutions, construction sites, professional fields, etc., to provide a reference for the further improvement and optimization of the national science and technology innovation platform system in the railway industry.

Through literature review, field investigation, expert consultation and other methods, this paper systematically investigates and analyzes the development status of the national science and technology innovation platform in the railway industry.

Taking the national science and technology innovation platform of the railway industry as the research object, this paper investigates and analyzes the construction, development and distribution of the national science and technology innovation platform of railway industry over the years. And the National Engineering Research Center of High-speed Railway and Urban Rail Transit System Technology was taken as an example to introduce its operation effect.

China Railway has made great development achievements, with the construction and development of national science and technology innovation platform in the railway industry. In recent years, a large number of national science and technology innovation platforms have been built in the railway industry, which play an important role in railway technological innovation, standard setting and commodification, and provide strong support for railway technology development.

High-speed turnouts are more complex in structure and thus may cause abnormal vibration of high-speed train car body, affecting driving safety and passenger riding experience. Therefore, it is necessary to analyze the data characteristics of continuous hunting of high-speed trains passing through turnouts and propose a diagnostic method for engineering applications.

First, Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) is performed to determine the first characteristic component of the car body's lateral acceleration. Then, the Short-Time Fourier Transform (STFT) is performed to calculate the marginal spectra. Finally, the presence of a continuous hunting problem is determined based on the results of the comparison calculations and diagnostic thresholds. To improve computational efficiency, permutation entropy (PE) is used as a fast indicator to identify turnouts with potential problems.

Under continuous hunting conditions, the PE is less than 0.90; the ratio of the maximum peak value of the signal component to the original signal peak value exceeded 0.7, and there is an energy band in the STFT time-frequency map, which corresponds to a frequency distribution range of 1-2 Hz.

The research results have revealed the lateral vibration characteristics of the high-speed train's car body during continuous hunting when passing through turnouts. On this basis, an effective diagnostic method has been proposed. With a focus on practical engineering applications, a rapid screening index for identifying potential issues has been proposed, significantly enhancing the efficiency of diagnostic processes.

As an important part of the management of railway passenger transport, the rationality and effectiveness of the clearing method of railway passenger transport are directly related to the operating efficiency and service quality of railway passenger transport enterprises. This paper aims to comprehensively and deeply discuss the evolution and development process of China's railway passenger transport clearing method, analyze its characteristics and influences in each stage, identify the main factors affecting its evolution and development and then put forward thoughts on improving the future development of the clearing method.

Through a detailed review of the railway passenger transport clearing methods from the planned economy period to the reform and opening up period and into the new century, the basis, mode, subject and object of clearing in different development stages are systematically compared.

It comprehensively reveals the evolution of the clearing method, sorted out the characteristics and changes of the clearing method at each stage and the adaptability to the development of railway passenger transport at that time. The characteristics of the development of clearing measures for railway passenger transport in different stages and their far-reaching influence on railway passenger transport business are deeply analyzed.

This paper summarized the factors influencing the development of China's railway passenger transportation clearing approach evolution, including the simplified rules of clearing, enhanced the market adaptability, establishing and perfecting the incentive mechanism, strengthening the construction of informatization, etc. This paper puts forward the ways to improve the railway passenger transportation clearing future development thinking.

This paper aims to provide a comprehensive analysis of the strategic adjustments in China's transportation structure, with a particular focus on the pivotal role of railway freight and its integration into the modern logistics system. It seeks to address the need for a more nuanced understanding of the "road to rail" policy, emphasizing the importance of intermodal collaboration and service of fragmented market demands.

The study employs a transport economics perspective to evaluate the achievements and shortcomings of China's transportation structure optimization. It bases its assessment of the current state of railway freight logistics, multi-modal transportation and the broader implications for the transportation service market on data analysis. The methodology includes a review of existing policies, an examination of industry practices and a comparative analysis with global trends in railway logistics.

The research underscores the importance of focusing on the development of non-bulk materials, noting the insufficiency in the development of China's rail multi-modal transportation and highlighting the instructive value of successful cases in open-top container road-rail intermodal transportation. The study posits that the railway sector must enhance cooperation with other market entities, aligning with the lead enterprises in the logistics chain that are characterized by speed, high value and strong coordination capabilities, in order to better serve the transportation market. This approach moves away from a reliance on the railway's own capabilities alone.

This paper offers original insights into the transformation of railway freight in China, contributing to the body of knowledge on transportation economics and logistics. It provides valuable recommendations for policymakers and industry practitioners, emphasizing the strategic importance of railway logistics in the context of China's economic development and intense competition in the supply chain. The value of the article lies in its comprehensive understanding of the complexities involved in the adjustment of transportation structures, providing direction for the market-oriented reform of China's railway freight sector.

To investigate the influence of vehicle operation speed, curve geometry parameters and rail profile parameters on wheel-rail creepage in high-speed railway curves and propose a multi-parameter coordinated optimization strategy to reduce wheel-rail contact fatigue damage.

Taking a small-radius curve of a high-speed railway as the research object, field measurements were conducted to obtain track parameters and wheel-rail profiles. A coupled vehicle-track dynamics model was established. Multiple numerical experiments were designed using the Latin Hypercube Sampling method to extract wheel-rail creepage indicators and construct a parameter-creepage response surface model.

Key service parameters affecting wheel-rail creepage were identified, including the matching relationship between curve geometry and vehicle speed and rail profile parameters. The influence patterns of various parameters on wheel-rail creepage were revealed through response surface analysis, leading to the establishment of parameter optimization criteria.

This study presents the systematic investigation of wheel-rail creepage characteristics under multi-parameter coupling in high-speed railway curves. A response surface-based parameter-creepage relationship model was established, and a multi-parameter coordinated optimization strategy was proposed. The research findings provide theoretical guidance for controlling wheel-rail contact fatigue damage and optimizing wheel-rail profiles in high-speed railway curves.

The bridge expansion joint (BEJ) is a key device for accommodating spatial displacement at the beam end, and for providing vertical support for running trains passing over the gap between the main bridge and the approach bridge. For long-span railway bridges, it must also be coordinated with rail expansion joint (REJ), which is necessary to accommodate the expansion and contraction of, and reducing longitudinal stress in, the rails. The main aim of this study is to present analysis of recent developments in the research and application of BEJs in high-speed railway (HSR) long-span bridges in China, and to propose a performance-based integral design method for BEJs used with REJs, from both theoretical and engineering perspectives.

The study first presents a summary on the application and maintenance of BEJs in HSR long-span bridges in China representing an overview of their state of development. Results of a survey of typical BEJ faults were analyzed, and field testing was conducted on a railway cable-stayed bridge in order to obtain information on the major mechanical characteristics of its BEJ under train load. Based on the above, a performance-based integral design method for BEJs with maximum expansion range 1600 mm (±800 mm), was proposed, covering all stages from overall conceptual design to consideration of detailed structural design issues. The performance of the novel BEJ design thus derived was then verified via theoretical analysis under different scenarios, full-scale model testing, and field testing and commissioning.

Two major types of BEJs, deck-type and through-type, are used in HSR long-span bridges in China. Typical BEJ faults were found to mainly include skewness of steel sleepers at the bridge gap, abnormally large longitudinal frictional resistance, and flexural deformation of the scissor mechanisms. These faults influence BEJ functioning, and thus adversely affect track quality and train running performance at the beam end. Due to their simple and integral structure, deck-type BEJs with expansion range 1200 mm (± 600 mm) or less have been favored as a solution offering improved operational conditions, and have emerged as a standard design. However, when the expansion range exceeds the above-mentioned value, special design work becomes necessary. Therefore, based on engineering practice, a performance-based integral design method for BEJs used with REJs was proposed, taking into account four major categories of performance requirements, i.e., mechanical characteristics, train running quality, durability and insulation performance. Overall BEJ design must mainly consider component strength and the overall stiffness of BEJ; the latter factor in particular has a decisive influence on train running performance at the beam end. Detailed BEJ structural design must stress minimization of the frictional resistance of its sliding surface. The static and dynamic performance of the newly-designed BEJ with expansion range 1600 mm have been confirmed to be satisfactory, via numerical simulation, full-scale model testing, and field testing and commissioning.

This research provides a broad overview of the status of BEJs with large expansion range in HSR long-span bridges in China, along with novel insights into their design.

To systematically characterize and objectively evaluate basic railway safety management capability, creating a closed-loop management approach which allows continuous improvement and optimization.

A basic railway safety management capability evaluation index system based on a comprehensive analysis of national safety management standards, railway safety rules and regulations and existing safety data from railway transport enterprises is presented. The system comprises a guideline layer including safety committee formation, work safety responsibility, safety management organization and safety rules and regulations as its components, along with an index layer consisting of 12 quantifiable indexes. Game theory combination weighting is utilized to integrate subjective and objective weight values derived using AHP and CRITIC methods and further combined using the TOPSIS method in order to construct a comprehensive basic railway safety management capability evaluation model.

The case study presented demonstrates that this evaluation index system and comprehensive evaluation model are capable of effectively characterizing and evaluating basic railway safety management capability and providing directional guidance for its sustained improvement.

Construction of an evaluation index system that is quantifiable, generalizable and accessible, accurately reflects the main aspects of railway transportation enterprises' basic safety management capability and provides interoperability across various railway transportation enterprises. The application of the game theoretic combination weighting method to derive composite weights which combine experts' subjective evaluations with the objectivity of data.