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With the rapid developments of fifth generation (5G) mobile communication networks in recent years, different use cases can now significantly benefit from 5G networks. One such example is high-speed trains found in several countries across the world. Due to the dense deployment of 5G millimetre wave (mmWave) base stations (BSs) and the high speed of moving trains, frequent handovers (HOs) occur which adversely affect the Quality-of-Service (QoS) of mobile users. User association for load balancing is also a key issue in 5G networks. Therefore, HO optimisation and resource allocation are major challenges in the mobility management of high-speed train systems. Handover Margin (HOM) and Time-to-Trigger (TTT) parameters are crucial for the HO process since they affect the key performance indicators (KPIs) of high-speed train systems in 5G networks. To manage system performance from the aspect of predictive analytics, we have modelled system performance of mobility management through machine learning (ML). First, the HO management process of a high-speed train scenario is framed as a supervised ML problem. The inputs for the problem are regression task, HOM and TTT and the outputs are key performance indicators (KPIs). Second, data processing is accomplished after generating a simulation dataset. Several methods are employed for the dataset, such as Adaptive Boosting (AdaBoost), Gradient Boosting Regression (GBR), CatBoost Regression (CBR), Support Vector Regression (SVR), Multi-layer Perceptron (MLP), Kernel Ridge Regression (KRR) and K-Nearest Neighbour Regression (KNNR). Tenfold cross validation is then applied for choosing the best hyperparameters. Finally, the deployed methods are compared in terms of the Mean Absolute Error (MAE), Mean Square Error (MSE), Maximum Error (Max E), and R2 score metrics. From the MAE results, CBR achieves the best outcomes for load level and throughput KPIs with 0.003 and 0.0144, respectively. On the other hand, GBR achieves the best results for call dropping ratio (CDR), radio link failure (RLF) and spectral efficiency KPIs with 0.354, 0.082 and 0.354, respectively. CBR also follows GBR for the three KPIs with 0.356, 0.082 and 0.357, respectively. Only a slight difference in estimations is present. MLP achieves the best results for HO ping-pong (HOPP) and HO probability (HOP) KPIs with 0.0045 and 0.011, respectively. This is followed by GBR and CBR. From the MSE outcomes, CBR and GBR exhibit the best results for load level and throughput KPIs with 2e-5 and 3e-5, respectively. GBR attains the best results for CDR, RLF and spectral efficiency KPIs with 0.25, 0.011 and 0.025, respectively. Accordingly, CBR follows GBR with slightly different errors for the three KPI estimations. MLP achieves the best results for HOPP and HOP KPIs with 5e-5 and 3.6e-5, respectively. Again, this is followed by GBR and CBR for the estimation of these results. This indicates that CBR and GBR can capture relationships between inputs and KPIs for the dataset used in this study, outperforming all other methods generally used for solving this problem. [ABSTRACT FROM AUTHOR]

The operational capability of high-speed railways after an earthquake is crucial in post-seismic rescue efforts. In this study, the impact of seismic-induced residual deformations and stiffness degradation on the post-seismic operational capabilities of high-speed railway bridges was explored. A comprehensive post-seismic operational performance analysis of high-speed trains was conducted by integrating seismic-induced residual geometric irregularities of the track surface with dynamic irregularities of the track-bridge system. Further, post-seismic running speed demands for high-speed trains were proposed, and the amplitude limits for seismic-induced track irregularities were defined based on probability assurance rates under varied states of train operational performance indicators. In addition, the impact of ground motion intensity on the running speed demands of high-speed trains, emphasizing safety, was examined, identifying a spectrum of sensitive wavelengths for seismic-induced track irregularities that could influence lateral vibrations of high-speed trains at various speeds. The results indicate that the post-seismic operational capacity of the track-bridge system and the running speed demands for high-speed trains diminish as ground motion intensity increases. Further, the performance indicators for high-speed trains significantly increase with the amplitude of seismic-induced irregularities. Relying on the derailment coefficient as a safety measure tends to overestimate the post-seismic operational capacity of the track-bridge system. The derailment coefficient for high-speed trains significantly increases as the wavelength of post-seismic track surface irregularities decreases. Therefore, mid-range seismic-induced track irregularities, particularly those spanning 30–70 m, warrant increased attention within the 150–350 km/h speed range. • It explores train post-seismic performance based on seismic-induced irregularity. • It poses post-seismic speed demands and limits of seismic-induced irregularities. • It gives sensitive wavelengths of seismic-induced track alignment irregularities. [ABSTRACT FROM AUTHOR]

• We empirically test economic impacts of China's high-speed railways (HSRs) network. • Our spatial econometric model confirms that HSR drives local economic growth. • However, the spill-over effect is insignificant. • HSR significantly increases growth in large-mega cities and developed cities. • However, it could widen economic disparity in China. China's high-speed railways (HSRs) networks have dramatically expanded since 2008, which is widely believed to have promoted economic growth. This study empirically tests this hypothesis and analyses the impact of HSRs on economic disparity between 2002 and 2016 in China using a spatial econometric model. The results confirm the role of HSRs as a driving force in promoting local economic growth, although the spill-over effect is found to be insignificant. However, the cross-city analysis suggests there are heterogeneous effects of HSRs on economic growth. By dividing the sample into small-medium cities and large-mega cities, as well as least-developed, developing, and developed cities, this study finds that HSRs make a significant positive contribution to economic growth in large-mega cities and developed cities but has insignificant effects in other cities. The results indicate that HSRs can widen economic disparity in China. Our findings not only advance the understanding of the role of HSRs in promoting China's economic growth but also provide insights for planning future HSR networks. This study concludes that each city should reasonably plan its HSR network to promote economic growth and reduce economic disparity by accounting for different resource endowments, especially geographic and population factors. [ABSTRACT FROM AUTHOR]

The concrete roadbed in the Beijing-Shenyang high-speed railway (HSR) is being serviced for the first time in HSR construction history. Rail inspections have shown that the extreme temperature conditions in seasonally freezing regions can significantly influence the curling behavior of concrete roadbeds. This paper presents an in situ experiment to fundamentally evaluate the impact of seasonal temperature variations on the curling behavior of concrete roadbeds. Herein, a thermomechanical coupled finite element (FE) model is built and calibrated with experimental data. Then, specific consideration is given to the curling mitigation measures, including adjusting the thickness, length, and construction form of the concrete roadbed. Mitigating upward-curling behavior by increasing the thickness of the concrete roadbed will result in severe downward-curling behavior during one year of service. Finally, an active groove-setting construction form is suggested to prevent curling from the temperature variations in the concrete roadbed. In general, this study further enhances the common understanding of the temperature curling behavior of concrete roadbeds serviced in an HSR. [ABSTRACT FROM AUTHOR]

• We construct an innovative index that combines the network accessibility and connectivity to measure HSR. • At the whole-YRD level, HSR network alleviates the urban-rural income disparity and exhibits a stronger positive impact on the rural residents' income. • This study finds spatiotemporally heterogeneous impacts of HSR network on urban–rural income disparity by employing GWR, TWR and GTWR models. • The varying effect is in view of differences in tertiary-industry development and economic growth. The socioeconomic effects of China's fast-growing high-speed railways (HSRs) have become a popular issue in recent decades. However, few studies have examined how HSRs alleviate the urban–rural income disparity temporally and spatially; the current research addresses this gap in the literature from novel network accessibility and connectivity perspectives. Using different spatiotemporal models to analyze the Yangtze River Delta in China, the main findings are as follows: (1) there is evidence that the HSR network alleviates the urban–rural income disparity and exhibits a stronger positive impact on rural residents' income; (2) compared with HSR accessibility, HSR connectivity affects the income disparity in a more significant manner; (3) due to its advantage in capturing the spatiotemporal heterogeneities of HSR's impact, the geographically and temporally weighted regression (GTWR) model demonstrates a higher accuracy than other models; (4) the GTWR model results show that the HSR network affects the income disparity both negatively and insignificantly in Northern Jiangsu or Southwestern Zhejiang, while this effect is significant in other regions; and (5) further empirical evidence indicates that this varying effect is in light of differences in tertiary industry development and economic growth. These findings provide a novel opinion of HSR's socioeconomic effects and present useful empirical support for solving the serious urban–rural income disparity problem in China. [ABSTRACT FROM AUTHOR]

Highlights • A multi-train cooperative control model was proposed based on CACC. • We improved the rolling horizon approach into a novel self-triggered model predictive control scheme. • Train controller output constraints and safe train following distance were considered. • The simulation results were analyzed to demonstrate the effectiveness of the proposed approach. Abstract The advanced train-to-train and train-to-ground communication technologies equipped in high-speed railways have the potential to allow trains to follow each with a steady headway and improve the safety and performance of the railway systems. A key enabler is a train control system that is able to respond to unforeseen disturbances in the system (e.g., incidents, train delays), and to adjust and coordinate the train headways and speeds. This paper proposes a multi-train cooperative control model based on the dynamic features during train longitude movement to adjust train following headway. In particular, our model simultaneously considers several practical constraints, e.g., train controller output constraints, safe train following distance, as well as communication delays and resources. Then, this control problem is solved through a rolling horizon approach by calculating the Riccati equation with Lagrangian multipliers. Due to the practical communication resource constraints and riding comfort requirement, we also improved the rolling horizon approach into a novel self-triggered model predictive control scheme to overcome these issues. Finally, two case studies are given through simulation experiments. The simulation results are analyzed which demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Even a small amount of settlement is critical in the operation of high-speed railways. Recently, in Korea, additional settlement was observed at many sites of high-speed railways after the construction of concrete tracks including sites where ground improvement methods were applied. Among 1,118 observing sites, 95 sites experienced the settlement exceeding the control limit of high-speed railways. The present work described factors causing additional settlement in high-speed railways. Geological features, embankment height, layer thickness, ground improvement method, groundwater drawdown, compaction of frozen soil, and dynamic loading by train operation were selected as the potential factors of the additional settlement. Analysis results showed that high settlement was measured in concrete tracks that were constructed over alluvium and biotite granodiorite layers (85.76%) and the settlement increased according to the increase of the embankment height and the thickness of the subgrade layer. In 92.63% of high settled sites, a sudden increase of settlement caused by groundwater drawdown was observed during the dry season as well. Also, compaction of the embankment during winter and dynamic loading by train operation increased the settlement to a certain degree. [ABSTRACT FROM AUTHOR]

The pantograph–catenary system (PCS) vibration causes the pantograph–catenary contact force (PCCF) to fluctuate, deteriorating current collection quality and damaging the electrical equipment. The active pantograph is one of the most promising methods for suppressing PCS coupling vibration and improving the current collection quality of high-speed trains. This paper first summarizes the research progress of five critical links in the active pantograph, including PCS modeling, control algorithm, hardware support, and HIL test verification. Then, the impact of the PCS model on numerical simulation accuracy and calculation time, the pros and cons of different control algorithms, and the execution mechanism selection are discussed. Finally, the active pantograph's future development trend and research direction are prospected, such as model optimization, algorithm design, and signal correction. The analysis results show that establishing the PCS model should consider the representation of system dynamics and calculation efficiency. Control targets need to reflect the current collection quality comprehensively, and the measurement system needs to minimize the effect of locomotive disturbances on the observation results. The actuator structure needs to execute the control commands efficiently and quickly without affecting the operation of the raising mechanism. These factors, together with the real-time control algorithm, determine the practical effectiveness of the active pantograph. [ABSTRACT FROM AUTHOR]

This paper investigates the high-speed train rescheduling (HSTR) problem under a partial station blockage and proposes an efficient problem-specific strengthen elitist genetic algorithm (PS-SEGA) for HSTR. Firstly, a HSTR model subject to train operation constraints is established to minimize the total train delay. A permutation-based encoding method is developed to define an efficient search space based on the train departure sequence. A heuristic decoding method is employed to eliminate all train operation constraints and output the rescheduled timetable. Moreover, a hybrid initialization method involving an efficient heuristic strategy (EHS) is put forward to accelerate the convergence speed of PS-SEGA. Using problem-specific knowledge, EHS generates an efficient and feasible solution for the initial population. Finally, a restart strategy is presented to maintain genetic diversity. Compared with other advanced evolutionary algorithms and their improved variants also using the improvements of PS-SEGA, experimental results demonstrate the effectiveness of the proposed PS-SEGA for addressing HSTR scenarios under the partial station blockage. As for the scenarios that CPLEX cannot obtain optimal solutions within 10 min, PS-SEGA can provide quasi-optimal solutions in real time. Furthermore, compared with the other two heuristics algorithms (i.e., First-Scheduled-First-Served and EHS), PS-SEGA can give the train departure sequence with a smaller total train delay. • A high-speed train rescheduling model with time constraints is established. • A permutation-based encoding method is proposed to improve solution efficiency. • A heuristic decoding method is developed to eliminate all time constraints. • Problem-specific knowledge is designed to provide an efficient rescheduling solution. • Ten real-world cases are used to verify the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Based on the panel data of 280 prefecture-level cities in China from 2007 to 2019, we took the opening of high-speed railways (HSRs) as the "quasi-natural test" and employed propensity score matching (PSM)-difference in difference (DID) method to empirically test the agglomeration effect of the opening of HSRs on the urban logistics industry and the heterogeneity of cities according to location types and urban grade classification. The results show that the opening of HSRs has an impact on the spatial layout of logistics industry by promoting urban economic growth and gathering labor. In the dynamic balance of agglomeration and diffusion, the logistics industry gradually spreads to the surrounding areas of the city through the opening of HSRs. The opening of HSRs has a heterogeneous impact on the agglomeration effect of urban logistics industry. For the rapidly developing first-tier, second-tier and third-tier cities, the opening of HSRs has a significant impact on the agglomeration of their logistics industry and promotes its diffusion to those surrounding cities. On this basis, this paper puts forward corresponding suggestions for the development of the logistics industry and tries to make full use of the development opportunity brought by the opening of HSRs to promote the development of the logistics industry. • The agglomeration effect of HSRs opening on logistics industry is tested by PSM-DID method. • The panel data of 280 prefecture-level cities in China is used in empirical research. • The heterogeneity is discussed according to the location and class of cities. • HSRs impact the agglomeration and diffusion of logistics industry greatly. • Implications are provided to develop the logistics industry and to make full use of the HSRs. [ABSTRACT FROM AUTHOR]

High-speed railways have quickly gained popularity as an environmentally beneficial mode of transportation. In addition, converters and electric motors are becoming more widely used. However, power converters and motors can act as constant power loads when tightly controlled, making the source converters unstable. In this article, robust fuzzy control is proposed for stabilizing power electronic converters feeding a constant power load in a high-speed train. The negative incremental resistance characteristics of the trains are first investigated. Then, utilizing the Takagi–Sugeno fuzzy model and the parallel distributed compensation approach, a robust stabilizing controller is constructed to ensure asymptotic descent of the dynamic system state trajectories toward the equilibrium position. Moreover, using linear matrix inequalities, the intended control gain can be automatically computed. The critical adjustment time of the controller and total harmonic distortions of the line currents are selected to measure and compare the dynamic stability of the designed controller. The suggested technique not only maintains global stability in the face of considerable changes in the constant power loads, but it also offers a fast dynamic reaction time and precise tracking over a wide operating range. Finally, simulations and experiments are performed to validate the proposed approach. [ABSTRACT FROM AUTHOR]

Aim In recent years the Spanish Geotechnical Laboratory of CEDEX (Centro de Estudios y Experimentación de Obras Públicas) has developed for ADIF (Administrador de Infraestructuras Ferroviarias) a series of monitoring techniques (with different types of sensors) to be used in combination with numerical models in order to define the vertical dynamic behavior of the track structure in high-speed railways. Currently we are extending our work with the purpose of monitoring and studying also the horizontal response of the track superstructure. In this contribution we present our methods for measuring vertical and horizontal displacements and loads on the rail in high-speed railways. Method Numerical models have been used to evaluate results from different instrumentation configurations that have been designed to measure horizontal displacements and loads on the rail. Several tests in the CEDEX real scale track box facility have also been carried out. The obtained data have been interpreted in the light of the numerical models. In this way we have been able to pick out the best configurations, which have been later put in a real high-speed rail section. Besides, we have studied relationships between simultaneous measurements of horizontal force on the rail and horizontal rail-sleeper relative displacement. A good correlation between both parameters has been observed. New tests are being carried out in the CEDEX real scale track box facility with the purpose of optimizing the developed techniques and improving the numerical model calibration. Results With all these techniques we are improving the knowledge of different railway sections (sections with significant thickness of ballast, transitions slab track - ballasted track, sections with bituminous sub-ballast, etc.), and optimizing their design. New techniques for analyzing the horizontal behavior of high-speed railways have been developed based on numerical models and different tests carried out in the CEDEX real scale track box facility. [ABSTRACT FROM AUTHOR]

Sleepers are the primary structural components that provide the necessary gauge width and the structural stability to the ballasted railway track. High performance prestressed concrete sleepers of high-speed railways have strict design and production requirements to provide a safe, serviceable and a reliable railway superstructure. The production dimensions of a contemporary prestressed high performance concrete sleeper are within low tolerance values on the scale of a millimeter that is uncommon for ordinary structural concrete elements. Railways are within climatic conditions that could become effective in the dimensional stability of their sleepers. Within regions of low humidity levels, in addition to the elastic shortening of the prestressed sleepers, the effects of concrete creep and shrinkage could lead to total contraction values in excess of the allowed tolerances for the shoulder width of the sleepers. Therefore the dimensional design of a high performance prestressed concrete sleeper must include the effects of time dependent dimensional changes. This paper presents the possibility of falling out of dimensional tolerance for prestressed high performance sleepers and ways to mitigate those possibilities for railways in arid climatic conditions or within climatic zones undergoing a climate change. [ABSTRACT FROM AUTHOR]

The flying ballast phenomenon has become an important problem, in the last years, because of the development of high speed trains and the consequent increase of the speed up to 350 km/h. The problem is very complex since it is related to both railway infrastructure and train characteristics and since it involves mechanical and aerodynamic effects. The results of an experimental study carried out on the Italian high-speed railway and on a 1:1 real stretch of the railways in wind tunnel are presented in the paper. The study was aimed to analyze the effects of the height of the ballast level, the stone shape in the upper layer of the ballast and the compaction of the ballast bed on the problem. To this purpose a specific wind tunnel test rig was designed to reproduce in the wind tunnel a flow with the same average characteristics of the one measured on the real line, especially in the region close to the ballast and sleepers. Finally, starting from the results of these tests, possible countermeasures to ballast lifting on-set are proposed. [ABSTRACT FROM AUTHOR]

It has been proven that cyclic loading induced by the circulation of trains at very high speeds (>300 km/h) results in important track vibrations progressively amplified in a repeated process leading to the deterioration of track geometric quality and an unwanted increase in track maintenance needs and track life cycle costs. Having this as concern, the present paper focuses on a numerical model which was built to correctly predict train/track dynamic response (confidence assured by an extensive validation process with real experimental measurements in railway high speed lines) not only instantaneously but also in a long-term perspective. The innovation consists on the fact that the same tool enables both accessing track vibration levels and evaluating track settlement evolution throughout millions of cyclic train passages, maintaining low computing time. Different track design solutions are simulated, such as: softening railpads, applying under sleeper pads, placing ballast mats or using bituminous subballast as an alternative to granular subballast. Results are evaluated in the perspective of track vibrations mitigation and track maintenance needs. [ABSTRACT FROM AUTHOR]

Abstract: Transport networks are hierarchal in essence. In this paper, we explore the relationship between the financing structure and the hierarchal evolution of railway network development, using the case of China. Although privatization and corporatization in transport provision have been trends in some parts of the world, the national government is still the main body responsible for railway development in many countries. Among these countries, China and India are the only two that include the Ministry of Railways (MOR). In India, the entire country''s railways are clearly defined as public services provided and managed by the MOR. In China, railways have been corporatized; yet, the MOR and the National Railway Corporation are still widely regarded as a single body that has monopolistic power over almost all railway systems at the national and regional levels in both infrastructure development and operation. We argue that when multi-level railway networks are evolved from a single-level (national) network due to market growth in countries such as China, where different levels of government are responsible for infrastructure planning and development, the state’s monopolistic control of operation and its corresponding financing structure may not fit the operation of new multi-level networks. However, the suitable institutional set-up for the new networks may be delayed or never established for many reasons, some of which, as demonstrated in this paper, are place-specific and path-dependent. The case study of Chinese railway systems in comparison with the situations of other Asian countries (i.e. India and Japan) will shed some light on a better understanding of various financing models and development paths of multi-level transport. [Copyright &y& Elsevier]

Abstract: Railways are an important critical infrastructure because they transport commodities and goods (freight rail) and people (passenger rail). Like other critical infrastructures, the railway infrastructure is complex and geographically dispersed and has become increasingly dependent on information and communications technology (ICT). Therefore, the mitigation of ICT vulnerabilities is essential for protecting the railway infrastructure. This paper focuses on the European high-speed railroad infrastructure, in which a wireless system based on the Global System for Mobile Communications for Railways (GSM-R) standard plays an important role in distributing signaling information to trains. The paper examines the GSM-R vulnerabilities due to wireless interference and describes an innovative monitoring system based on software-defined radio technology that is designed for the early detection of wireless interference. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of geographic proximity on mergers and acquisitions (M&As). In recent years, the Chinese government has invested heavily in high-speed railway (HSR) construction, which has greatly reduced the commuting time between connected cities and facilitated cross-city investments. Therefore, we exploit whether two cities were connected by an HSR as a quasi-natural experiment to identify the causal relationship between geographic proximity and M&As. We find that the number of M&As between two HSR-connected cities increases by 9.6% after adopting HSR service. Additional results show that HSRs have reduced the average time of completing M&A transactions by 29.4% and increased the subsequent economic performance of the acquirers. A mechanism analysis shows that HSRs promote M&As mainly by alleviating the information asymmetry between acquirers and targets and promoting monitoring on targets. • We study the effect of geographic proximity on mergers and acquisitions (M&As). • We use the adoption of high-speed railway (HSR) as an exogenous shock to identify the causality. • The M&A deals between two HSR-connected cities increase by 9.6% after adopting HSRs. • HSRs facilitate M&As by alleviating information asymmetry and promoting monitoring. [ABSTRACT FROM AUTHOR]

• The influence of non-linear soil properties on critical speed in railway lines is investigated for both slab and ballasted tracks. • Two models are used: a 3D FEM approach, and a novel dispersion curve technique. • The influence of the Plastic Index (PI), the soft soil thickness and train load magnitude are assessed. • The soil non-linear behaviour plays a very important role in ballasted tracks, while on slab tracks the influence is not so expressive. • For ballasted tracks, the relationship between the critical speed and shallow upper soil layer thickness can be weak. The design of high-speed railway lines involves geotechnical challenges, one of which is the risk of dynamic track amplification, for example on track sections where the train speed approaches the track-ground critical speed. In these cases, soil strains increase significantly with an increase in train speed, far exceeding the limits of linear elastic behaviour. This can result in a non-linear reduction of soil stiffness. To better understand this relationship, this paper studies the influence of soil non-linearity on the critical speed of concrete slab and ballasted tracks. To perform an in-depth analysis into non-linear critical speed, two models are used: a 3D FEM approach, and a novel dispersion curve technique. Using the models, the effect of soil plasticity on non-linearity is studied, with different ranges of plasticity found to play an important role. Secondly, the influence of soil thickness and loading magnitude are evaluated. It is shown that ballasted tracks are deeply affected by the non-linear soil behaviour, compared to a concrete slab track. Further, it is shown that for the ballasted tracks, the relationship between the critical speed and shallow upper soil layer thickness can be weak. [ABSTRACT FROM AUTHOR]

Abstract: After collecting information on 166 high-speed rail (HSR) projects across the world, this paper examines some of the most relevant empirical issues related to the implementation of this transport technology in recent years. We firstly discuss the economic definition of HSR, trying to identify its different development and operating models. Then, we provide what could be considered as a range of actual cost values of building and maintaining a high-speed rail infrastructure. A similar analysis is carried out regarding the operating and maintenance costs of high-speed rail services. Some information on external costs is also provided. We finally deal with current demand and its projections, and try to draw some inferences about its future evolution. [Copyright &y& Elsevier]

Many studies have found that the operation of high-speed railways (HSRs) is accompanied by local economic benefits at the gross domestic product level. However, the effects on the per-capita disposable income of residents and the idea of an even sharing of their economic benefits are still unclear. To fill this research gap, this study investigates the impacts of HSR operation on resident income from 2008 to 2018 in China by using the multi-stage difference-in-differences (DID) and propensity score matching DID methods. The results suggest that both rural and urban residents in central China and rural residents in the eastern region benefit from HSRs. Further, rural residents of cities with a higher reliance on the primary industry and urban residents of cities with a more developed tertiary industry benefit more from HSRs. Our findings provide new insights into the socioeconomic effects of HSR construction. • We empirically investigate who benefit from China's high-speed railway network use the multi-stage DID and PSM-DID methods. • Rural and urban residents in central China benefit from HSRs. • Rural residents in the eastern region also benefit from HSRs. • Rural residents with high reliance on the primary industry benefit more from HSRs. • Urban residents with a more developed tertiary industry benefit more from HSRs. [ABSTRACT FROM AUTHOR]

• Inter-organizational coordination for HSR rolling stock is important for safety. • FRAM is used to model an incident and study inter-organizational complexity. • Accidents can occur even when operators and manufacturers coordinate during design. • Coordination should focus on micro-level integrated systematic risk-management. • Moving beyond self-regulation, regulatory facilitation is necessary for solutions. The current study analyzes safety issues that emerge owing to complex inter-organizational coordination between operators and manufacturers of high-speed railway (HSR) rolling stock, a topic rarely discussed in previous literature despite the prominence of HSR as an advanced transport mode. Risk factors pertinent to inter-organizational coordination between HSR stakeholders and solutions for managing these risk factors are critically examined through the functional resonance analysis method (FRAM) of an authentic safety incident. The analysis is conducted using official investigative reports and accounts of the incident triangulated from multiple sources within the Japanese HSR industry. Based on an FRAM-based taxonomical analysis of the theoretical solutions and considering the feasibility of the generated solutions, this study provides comprehensive and novel recommendations on the required characteristics of inter-organizational coordination for enhanced safety. In contrast to existing studies on safety coordination, the study finds that increased inter-organizational coordination between stakeholders directly involved in the process may not be sufficient to improve safety and that regulatory facilitation may be necessary. Moreover, the study concludes that the necessary coordination between stakeholders across the safety management process should be structured in order to conduct industry-wide integrated systematic risk assessments. [ABSTRACT FROM AUTHOR]

The aim of the present study consists of evaluating the influence of the most relevant geometric, mechanical and aerodynamic vehicle properties in the risk of derailment caused by crosswinds. To achieve this objective, a vehicle-structure interaction model is used to carry out non-linear dynamic analyses to assess the train-track coupling behaviour in the presence of winds. By computing the wheel-rail contact forces, the derailment risk is evaluated based on the unloading criterion, as suggested by the European Norm EN 14067–6 (2016), for several scenarios with different train and wind speeds. The wind is simulated with a stochastic model that allows the generation of turbulent wind time-histories based on power spectral density functions. The reference vehicle adopted in this work corresponds to the European InterCity Express 3 (ICE-3) train, whose original properties were parameterized in order to evaluate their influence in the vehicle's stability. The parametric study focused on several properties of the vehicle, namely the carbody mass, height of the gravity centre, aerodynamic coefficients, and stiffness and damping of the suspensions. Apart from the suspensions' properties, which prove to have a negligible influence in the vehicle's stability, the remaining parameters have a significant impact in the running safety against crosswinds. • Influence of the train parameters in the overturning derailment risk due to crosswinds. • Suspension properties have a negligible influence on the vehicle's stability against lateral winds. • Carbody mass stabilizes the train and decreases the risk of derailment. • ·Variations of 40% of the carbody mass or aerodynamic coefficients lead to variations up to 30% of the critical wind speeds. • The decrease of the aerodynamic coefficients leads to a considerable performance improvement against overturning risk. [ABSTRACT FROM AUTHOR]

• State-of-the-art review on train running safety on bridges. • International normative criteria regarding the train running safety on bridges. • Review of the main derailment mechanisms and safety criteria. • Effects of natural hazards, crosswinds and earthquakes, in the train stability. • Influence of track defects and induced deformations in the train stability. Train running safety is a major concern among railway engineers, since a derailment may cause significant personal and material damages. This problem becomes more important if the derailment occurs on bridges, especially at high-speeds, where the consequences may be even worse. The sudden development of high-speed (HS) railway networks that occurred at the end of the 20th century and beginning of the 21st century demanded the construction of new lines with large curve radii in order to fulfill the design requirements of this type of transport. By adding this fact to the orography constraints and, in some cases, to constraints related with the lack of construction area and with the high costs of expropriation, several HS lines started to be developed with more than 75% of their length built over viaducts and bridges. Naturally, this relatively new reality led to a significant increase in the probability of a train being exposed to natural hazards that might jeopardize its stability when it is running over an elevated structure. Hence, this paper aims to present a comprehensive literature review of the problematic associated with the train running safety assessment on bridges. The existing normative criteria from different regions of the world related to this topic are summarized in a first stage. Then, the paper gives a brief description of the available train-bridge interaction models needed to explicitly assess the traffic stability, followed by a presentation of the running safety indexes used to assess the derailment risk. Finally, the available applications regarding the traffic stability against different sources of excitation are systematically reviewed and guidance to future research work on this topic is provided. [ABSTRACT FROM AUTHOR]

• Running safety of train moving in a continuous viaduct with different track conditions. • Train structure interaction method to analyze dynamic the coupling system. • Comparison of track indexes for real and perfect rigid bridge. • Good agreement between results and the limits proposed by European codes. • Viaduct flexibility did not influence the results with respect to the derailment risk. This paper addresses the evaluation of the running safety of high–speed (HS) train moving over a continuous viaduct with different track conditions, ranging from very well-maintained to the worst condition possible according to the European recommendations, referred to as the safety limit. The case study focuses on the "La Scarpe" viaduct, which consists of a continuous nine-span steel–concrete composite bridge belonging to the French HS railway line TGV Nord, and on the German HS train ICE3 composed by eight independent cars. Firstly, the analysis is carried out considering the flexibility of the viaduct through train–bridge interaction (TBI) coupling system, where the running safety is analyzed according to Nadal, Prud'homme and Unload criteria. The results are then compared with those obtained using a rigid structure, which allowed to draw important conclusions regarding the effects of the viaduct's vibrations. From the results it was possible to conclude that the criteria have shown a good agreement with the limits laid down in the European norms. In addition, it was also possible to assume that the viaduct flexibility did not influence the results with respect to the derailment risk. Thus, for this particular case study, the train running safety assessment could be carried out using a simpler rigid structure model, which considerably reduces the degrees of freedom and the problem complexity without losing accuracy. [ABSTRACT FROM AUTHOR]

This article presents a study on the train stability against crosswinds simulated with different wind models. The work focuses on the evaluation of derailment indexes, which are dependent on the wheel-rail contact forces obtained through dynamic analyses performed with a vehicle-structure interaction methodology. The results obtained using the normative European Committee for Standardization (CEN) Discrete Gust model are compared with those obtained with a turbulent wind model based on stochastically generated wind fields. The calculations are performed considering several heights above the terrain to simulate the behaviour of a train running over a bridge deck located at different elevations. The CEN Discrete Gust model proved to be inaccurate and increasingly conservative, in relation to the Turbulent Wind model, as the height above the ground increases, since the former is based on a fixed turbulence intensity corresponding to the ground level, while the latter considers the correct turbulence intensity dependent on the deck elevation. Based on these results, the present article describes an alternative discrete gust approach that takes into consideration the variable turbulence intensity and terrain category in order to improve its applicability in the evaluation of the train running safety on bridges with decks located at different heights. • Train-structure interaction method to analyse the dynamic coupling system. • Train running safety analysis against crosswinds using different wind models. • Unloading criterion controls safety boundary for lower train speeds. • Limitations of the normative gust model for analyzing running safety on bridges. • Alternative to the CEN gust model to take into consideration different deck heights. [ABSTRACT FROM AUTHOR]

• Modelling of coupled vehicle–bridge–soil system with semi-analytical soil formulation. • Various modelling techniques are combined for computationally efficient solution. • High-order consistent lumped-parameter models produce numerically unstable systems. • Additional fitting procedures are implemented for numerically stable solution. • Created model is used for rapid evaluation of the effects of random track unevenness. Prediction of vibrations generated by railway traffic experiences an increasing interest, as new lines are being constructed and planned in many countries. The paper proposes a numerical model to analyse a coupled vehicle–bridge–soil system, taking into account the most important phenomena affecting the structure, while at the same time being comparatively computationally efficient. Such model is useful in the early design phases of a project, when analysing a range of possible configurations or conducting parametric analysis is required. A simplified vehicle model, nonlinear wheel–rail interaction, a bridge structure modelled using the finite-element method and a semi-analytical model for layered soil are all introduced in the model. A pure time-domain solution procedure is used, utilizing lumped-parameter models (LPMs) for the soil–foundation system. Representation of the dynamic stiffness matrix using LPMs is investigated by analysing the cross-coupling between footings and a novel procedure necessary for computationally stable LPMs is introduced and utilized. Further, pure time-domain solution is compared with an iterative mixed-domain solution. Finally, to illustrate the capabilities of the model, analyses are carried out to determine the resulting maximum and minimum excitation limits resulting from wheel–rail interaction on a number of randomly generated uneven track profiles. [ABSTRACT FROM AUTHOR]