Rail Transit In China Research Articles

Urban Rail Transit in China: Progress Report and Analysis (2015–2023)

AbstractThe urban rail transit (URT) system in China has undergone development spanning over 50 years. In the period from 2008 to 2015, numerous URT lines were under construction. After 2015, an increasing number of cities have transitioned to multi-line network operations, with greater emphasis on system efficiency and passenger service. This transition has been accompanied by numerous successful innovations and applications aimed at enhancing system intelligence and automation. This paper provides a review of operational statistics based on annual reports, successful operational practices, and industry development characteristics over the past decade in mainland China. Additionally, suggestions and trends for the further development of URT in China are proposed.

Greenhouse gas emission driving factors and reduction strategies for operational phase of urban rail transit in China

AbstractTo promote the sustainable development of urban rail transit (URT) in China, it is necessary to quantitatively analyze the greenhouse gas (GHG) emissions and its internal driving factors. Based on the LMDI algorithm, this research constructs an assessment model and makes a quantitative analysis of internal driving factors for GHG emissions in the operational phase of the URT system in China. According to the official investigated data, the GHG emission of URT in the operational phase is between 600 × 104 and 2000 × 104 tons of carbon dioxide equivalent (CO2e) per year from 2012 to 2023. The results of the driving factors decomposition showed that the passenger demand intensity was the key and positive factor affecting carbon emissions in the operational phase and the contribution rate was 12.93%–60.81% from 2013 to 2023. Therefore, it is necessary to formulate targeted policies in terms of management and technical means to reduce the average traveling distance demanded by passengers and reasonably control the scale of the line network for GHG reduction in the Chinese URT system.

A Comprehensive Review of the Development Characteristics and Future Trends of TOD in Chinese Urban Rail Transit

The transit-oriented development (TOD) concept has become a significant catalyst for urban development in China, which has undergone rapid urbanization and has actively participated in the development of public transportation networks over the past 20 years. TOD not only guides the transformation of transportation modes but also leads the development of urban spaces. The extensive construction of urban rail transit in China highlights the universal patterns of TOD and reflects the uniqueness of Chinese practices. This paper analyzes the characteristics of urban development and TOD in developed countries, summarizing the common laws driving TOD in theoretical research. It then compares China, which is in a period of rapid rail transit construction, to identify the unique developmental laws of transit-oriented development of rail transit in China (TOD-RTC). The paper further examines the developmental characteristics of TOD-RTC in practice, considering both temporal and spatial aspects, and explores the reasons behind the formation of individual differences in TOD-RTC. Finally, it discusses the new value and potential that TOD brings to urban development, along with predicting future development trends.

Application of Digital Technology in the Operation and Safety of Rail Transit in China

Application of Digital Technology in the Operation and Safety of Rail Transit in China

Research on Scheme Selection of Rapid Low-floor Light Rail Vehicle

At present, there is no rail transit in China that can directly connect the main urban areas and satellite cities without passengers transferring halfway. In addition to the problem of passenger transfer, the construction of transfer stations presents a challenge to an already land-scarce city. In order to solve this problem, this paper introduces the status quo of rapid light rail technology in China and other countries, compares and analyzes the technical characteristics of rapid LRV, and finally puts forward suggestions on the selection of China’s rapid LRV scheme in the future.

Study on Dynamic Amplification Coefficient of U-Shaped Girder Based on Vehicle-Bridge Coupling Dynamics

In this paper, a vehicle-bridge coupling dynamic model is established considering the vertical wheel-rail tight contact and the lateral simplified wheel-rail creeping. Through the site test and the numerical calculation, the dynamic deflections and the stresses of the U-shaped girder in the Nanjing S6 Urban Rail Transit in China are obtained, and the effectiveness of the established numerical model is verified. By changing the vehicle types and speeds, the dynamic amplification coefficients (DAFs) of the vertical deflections and the biaxial stresses at the girder bottom including the key points at the plate and section intersections are calculated. The research shows that the distribution of the lateral stresses is more complex than that of the deflection and the longitudinal stresses. Based on the calculation results considering various vehicle types, it is suggested that the DAFs of the vertical deflections and the longitudinal stresses are taken as 1.30, and the DAF of the lateral stresses remains at 1.40 as stipulated by the code. The research of this paper is to provide a reference for the structural design and size optimization of the U-shaped girders for urban rail transit.

Analyzing the Passenger Waiting Tolerance during Urban Rail Transit Service Interruption: Using Stated Preference Data in Chongqing, China

To reduce traffic congestion and pollution, urban rail transit in China has been in a stage of rapid development in recent years. As a result, rail transit service interruption events are becoming more common, seriously affecting the resilience of the transportation system and user satisfaction. Therefore, determining the changing mechanism of the passenger waiting tolerance, which helps establish a scientific and effective emergency plan, is urgent. First, the variables and levels of the urban rail service interruption scenarios were screened and determined, and the stated preference questionnaire was designed using the orthogonal design method. Further, the data of the waiting tolerance of passengers during service interruptions were obtained through questionnaires. Second, combined with the questionnaire data, an accelerated failure time model that obeys the exponential distribution was constructed. The results indicate that factors such as the service interruption duration, travel distance, bus bridging, information accuracy, attention to operation information, travel frequency and interruption experience affect the waiting tolerance of passengers during service interruptions. Finally, combined with the sensitivity analysis of the key influencing factors, the policy analysis and suggestions are summarized to provide theoretical support for the urban rail operation and management department to capture the passenger waiting tolerance accurately during service interruptions and formulate an efficient, high-quality emergency organization plan.

Thermal environment and thermal comfort in metro systems: A case study in severe cold region of China

The urban rail transit in China has been booming, and improving the comfort of the riding environment is critical to ensuring its long-term development. However, few studies have investigated thermal comfort in metro systems in severe cold regions; moreover, there is a lack of data to support metro-related specifications. This study adopts a whole-process thermal comfort tracking method for investigating passengers' thermal responses and monitoring thermal environment during entering, riding, and leaving metro stations. Field studies are carried out in summer of 2018 and 2019 on two metro lines in Changchun, a typical city in severe cold regions of China. A total of 717 valid samples are obtained. The results show that thermal environment in metro systems is non-constant in spatial dimension. The overall thermal sensation in metro systems is slightly cool, and there is little cooling need in carriages, which can potentially save energy. The thermal comfort zone is obtained based on the acceptable temperature and humidity ranges for 80% of passengers. The comfort zone satisfies the Chinese code, and except for the platform is approximately 0.8–1.6 °C wider than that specified in ASHRAE 55–2017. Despite high humidity levels (up to 86.2%) in metro system, passengers feel comfortable at temperatures up to 24.7 °C. Meanwhile, the thermal comfort zone does not fall exactly within the air velocity range specified by ASHRAE 55–2017. This research provides valuable references for improving comfort specifications and environmental control in metro systems in severe cold regions.

Evaluation of the Operational Efficiency and Energy Efficiency of Rail Transit in China’s Megacities Using a DEA Model

To date, along with the rapid development of urban rail transit (URT) in China, the evaluation of operational efficiency and energy efficiency has become one of the most important topics. However, the extant literature regarding the efficiency of URT at the line level and considering carbon emissions is limited. To fill the gap, an evaluation model based on slacks-based measure (SBM) data envelopment analysis (DEA) is proposed to measure the efficiencies, which is applied to 61 URT lines in China’s four megacities. The findings are summarized as follows: (1) The average operational efficiency and energy efficiency of URT lines are low, and both have great room for improvement. (2) There are significant disparities in the efficiency of URT lines in the case cities. For instance, the average operational efficiency of URT lines in Guangzhou is higher than that of other cities, while the average energy efficiency of URT lines in Shanghai is higher than that of other cities. (3) The URT lines operated by state-owned enterprises have higher average operational efficiency, while the lines operated by joint ventures have higher average energy efficiency. Finally, some suggestions are provided to improve the efficiencies.

Genetic Algorithm-Based Intelligent Selection Method of Universal Shield Segment Assembly Points

The proportion of universal segment in tunnel construction is constantly increasing. A key factor affecting the quality of tunnel construction is the selection of the shield segment assembly points. Nevertheless, the quality and efficiency of the current manual selection method cannot be guaranteed. To realize a high correct rate, high efficiency and intelligence of universal segment assembly points selection, an intelligent selection method of assembly points is proposed. First, the objective function is established by considering the thrust cylinder stroke and shield tail gap differences. Second, to adaptively optimize the weights of the objective function, the working conditions are divided into 81 intervals, and a genetic algorithm is proposed to optimize weights in each interval. Third, a Monte-Carlo-based method is proposed to generate an example dataset, which is used for the genetic algorithm to optimize the weights. Finally, the proposed method was applied to the segment assembly points selection for Line 8 of the Zhengzhou rail transit in China. The results show that the method of assembly segment selection can reach a 90.6% correct rate in the field. The research results of this paper can be used for the selection of the universal shield segment assembly points.

Compensation of negative sequence for a novel AC integrated power supply system of urban rail transit

With the large-scale increasing demand for passenger transportation, the alternating current (AC) 25 kV traction power supply system (TPSS) of electrified railway is introduced into the construction of urban rail transit in China instead of the direct current (DC) TPSS. In order to suppress the negative sequence current and cancel the neutral section at the exit of traction substation of the AC TPSS, a novel AC integrated power supply system (IPSS) of the urban rail transit based on single-phase static var generator (SVG) is proposed, which the capacity of SVGs can be further reduced. The topology of the novel AC IPSS is introduced. By defining the constraint factors of negative sequence current and reactive power compensated, the comprehensive compensation model of negative sequence current and reactive power of the novel system is established based on the corresponding standards, which the full compensation and satisfactory compensation can be achieved. The method of determining the compensation scheme and the control strategy are proposed. Taking the actual data as an example, the effectiveness of the compensation scheme is proved. In addition, the correctness of the control strategy proposed is proved by simulation and experiment.

Experimental Study on the Relationship between Fatigue and Unsafe Behavior of Urban Rail Transit Drivers

In recent years there has been rapid development of urban rail transit in China. The train driver, as the direct controller of the train, plays an important role in subway operation, and their driving performance directly determines whether the train is safe or not. To explore the relationship between fatigue and unsafe behavior, a simulated driving experiment was designed to record the train driver’s behavior under fatigue and normal state. The changes of operation accuracy and timeliness are used in combination to reflect the train driver’s unsafe behavior. The results show that when the train driver is in a state of fatigue, their operation accuracy is 126% lower than in the normal state. In the operation timeliness index, the time required for the train driver to react and complete the action is 28.13% and 17.7% longer than that in the normal state. It is concluded that fatigued driving can easily lead to unsafe behavior which then leads to potential safety accidents.

The earthquake under the action of underground structure and the influence of the distance between adjacent buildings

With the large-scale construction of urban rail transit in China, subways often cross the bottom of surface buildings or are located near them. In order to study the complex catastrophic correlation effects of the underground structure of the subway, the soil and the adjacent existing structures under earthquakes. We carried out numerical simulation calculations to study the effects of underground structures and adjacent existing structures under earthquakes. The interaction law of nearby existing buildings, the influence mechanism of the neighboring building’s depth factors on the seismic response of the complex system, and the system’s seismic response law were determined.

Simulation and experimental study on vibration and acoustic characteristics of a continuous supported embedded track

With urban rail transit developing fast, there is an increasing demand for riding comfort and reduction of vibration and noise. Metro being the main public transportation facility of urban rail transit in China, faces more severe challenges. Metro tracks use a range of different vibration isolating ballasted track structures. Environmental vibration along metro lines is controlled by using so-called vibration isolating track structures. In doing so, many problems arise in the train-track system of metro lines, such as strong vibration and excessive wear of wheel/rail systems, causing vibration fatigue and noise. Embedded track is used as an option to reduce vibration and noise, usually applied for tramways. When applied to metro lines, embedded track faces challenge due to high speed, large axle load and more complex line conditions. When applied to metro lines, the acoustic characteristics of embedded track need to be re-evaluated. These characteristics were investigated through a combined method of simulation and experiment. In this study, the wheel and track acoustic radiation of the embedded track designed for metro is predicted firstly. Then the tests of vibration and acoustic of the embedded track are carried out to verify the accuracy of the model on the one hand, and compare with the common fastener track to obtain more aspects of vibration and noise on the other hand. This study can provide a basis for the application of embedded track in metro systems.

Research and design of data communication subsystem of urban rail transit CBTC system

With the intensive development of urban rail transit in China, urban rail transit has increasingly become the preferred mode of transportation for citizens due to its convenience and speed. The design and construction of an efficient and highly reliable urban rail transit system has become an urgent requirement for urban rail transit construction. This article mainly introduces the research and design of the data communication subsystem of the urban rail transit CBTC system, and intends to provide some ideas and directions for studying the data communication subsystem of the urban rail transit CBTC system. This article uses a variety of methods, such as consulting literature and information research on trademark system suppliers. The development status of CBTC system and data communication subsystem is analyzed, and the importance of data communication subsystem and the necessity of the entire CBTC system are analyzed. The experimental results of this article show that in the design, development and application engineering of the CBTC system, the DCS subsystem accounts for 55%, the system is complex, and the environment is changeable, occupying an important position. When the DCS has a problem, it may cause drive failure, affect normal functions, cause greater losses, and even cause huge safety accidents. Therefore, the reasonable, reliable and safe design of the DCS subsystem is of great significance.

Research on Preparation and Performance of Clay‐Based Shield Tunnel Nonsintered Bricks

With the rapid development of rail transit in China, the number and scale of underground engineering construction have increased significantly, and a large amount of shield muck has been generated, which has brought great challenges to the urban environment. The reuse of shield muck has become an important research direction in underground engineering construction. In this paper, a nonsintered brick is prepared with shield muck soil as the matrix. The influence of different doping amounts of lime, fly ash, cement, and polyvinyl alcohol on porosity, density, water absorption, saturation coefficient, compressive strength, and other properties was explored to realize the resource utilization of shield dregs and at the same time obtain excellent performance nonsintered bricks. Through research, it is found that when the lime doping amount is 10% and the cement doping amount is 5%, with the increase of the fly ash doping amount, the overall compressive strength increases significantly, and the maximum compressive strength can reach 13.69 MPa. Although the doping of trace amounts of polyvinyl alcohol reduces the compressive strength, it can significantly reduce the compressive strength and mass loss rate after 15 freeze‐thaw cycles.

Energy consumption analysis and multiple-criteria evaluation of high-speed trains with different marshaled forms in China

Because of the current state of global resource shortages and environmental degradation, energy-saving and environmentally friendly national policies and low-carbon concepts have attracted both individual and societal attention, especially for rail transit. The rapid development of high-speed railways and urban rail transit in China has presented increasing transport energy demands and environmental pressures. This paper conducts an energy consumption comparative analysis of high-speed trains with different marshaled forms, including 3, 5, 8, 10, 12, 16, 17 and 18 cars, using the delayed detached eddy simulation method. A wind tunnel test with a 3.6% difference is applied to verify the obtained numerical results. A multiple-criteria evaluation methodology is presented to select the optimal alternatives for the marshaled forms of high-speed trains, which considers economic, social and environmental factors. The 1318-km (820-mile) Beijing-Shanghai line and a 350-kph high-speed train are employed in this research. The results can effectively guide the engineering design of high-speed trains and provide an evaluation tool in the decision-making process for designers.

Problems and Countermeasures of Urban Rail Transit Construction in China

In the 21st century, the over dependence on cars in China’s urban development has led to a series of problems, which have seriously affected the development of contemporary cities. The problem of communication has become the bottleneck of the development of many cities in China. Therefore, the rise of urban rail transit is an inevitable trend. The construction and development of rail transit is an effective way to solve urban diseases, such as traffic congestion, traffic pollution, poor green travel environment and difficult parking. In the period of great development opportunity of rail transit, it is necessary to discuss how to scientifically plan urban rail transit system, promote urban intensive development and improve urban traffic conditions. Combined with the current situation of rapid development of urban rail transit in China, this article analyzes the main problems existing in the development of urban rail transit at present, and puts forward the guiding ideology and main countermeasures for the development of urban rail transit in the future: do what you can and develop steadily to effectively avoid the hidden dangers brought about by blind development; further strengthen the scientific nature of urban rail transit planning and maintain the seriousness of planning; further improve the investment and financing mode of urban rail transit. Some suggestions are also put forward for the key problems to be solved in the near future.

Study on the Influence of Buried Depth on Seismic Performance of Underground Structure

With the large-scale construction of urban rail transit in China, subways often cross the bottom of surface buildings or are located near them. In order to study the complex catastrophic correlation effects of the underground structure of the subway, the soil and the adjacent existing structures under earthquakes, we performed numerical simulation calculations based on ANSYS to conduct research on the effects of underground structures and adjacent existing structures under earthquakes. The interaction law of nearby existing buildings, the influence mechanism of the neighboring building’s depth factors on the seismic response of the complex system, and the system’s seismic response law were determined.

Operating Efficiency-Based Data Mining on Intensive Land Use in Smart City

The discordance between the operation of rail transit and surrounding land use is highlighted with the rapid construction of rail transit in China. The related research on coupling relationship is well needed. Taking 13 typical commercial service rail transit stations in Xi'an as the example, this article established the evaluation indicator of coordinated relationship between rail transit station operating efficiency and land use, and a data envelopment analysis (DEA)model was used to evaluate the coupling degree between them. According to the research results, the coupling development between operating efficiency and land use in Xi'an commercial service rail transit station is at a low level and there exists a huge difference between the two. Moreover, this research identified the key indexes that influence the coupling development of the two, namely Class-A, Class-B, and Class-R land use proportion, plot ratio, land use mixture and parking facility control, and determined the reasonable control range of these four indices. The research promotes the intensive use of land around Xi'an rail transit station and better supports the sustainable operation of rail transit.