Subway Entrance Research Articles

Simulation and Risk Assessment of Flood Disaster at the Entrance to a Rail Transit Station under Extreme Weather Conditions—A Case Study of Wanqingsha Station of Guangzhou Line 18

With the rapid development of urbanization and underground transportation, as well as the frequent occurrence of extreme weather conditions such as extreme rainfall, flooding disasters for rail transit are becoming severe, and need to be urgently clarified in terms of the mechanism causing them. In this study, a comprehensive model for water damage at the entrance to a rail transit station is proposed, emphasizing the entire process of extreme weather–surface ponding–underground intrusion. The model is validated by the inundation process of Line 5 of the Zhengzhou Metro during the “7.20” event and further applied to Wanqingsha Station of Guangzhou Metro Line 18 in China to determine the surrounding water depth, distribution, total water inflow volume, and water damage time under different rainfall intensities, rain patterns and protection scenarios. It was found that when rainfall reaches the level of a 1-in-2000-years event, the surface water begins to invade the internal rail transit system through the rail transit entrances. When facing extreme rainfall akin to the “7.20” event in Zhengzhou, the rail transit system in Wanqingsha Station meets a heightened risk of water damage, resulting in significantly deeper water levels compared to 1-in-5000-year rainfall event in Guangzhou and exceeds the height of the subway entrances. Analysis of the water intrusion process reveals that, as rainfall intensity escalates, the total inflow water volume into the rail transit system increases while escape time diminishes. Moreover, under identical rainfall intensity, pre-type rainfall yields the highest total water inflow, whereas mid-type rainfall exhibits the shortest escape time. Enhancing the protection conditions can markedly attenuate surface water intrusion into the subterranean rail transit system, thereby enhancing the evacuation time for individuals within the system.

Prioritizing Subway Station Entrance Attributes to Optimize Passenger Satisfaction in Cold Climate Zones: Integrating Gradient Boosting Decision Trees with Asymmetric Impact-Performance Analysis

Subway station entrances serve as crucial links between urban environments and underground transit systems and are particularly vital in cities with cold climates. Specialized design strategies are essential to address user needs and promote safety and comfort, thereby encouraging sustainable travel in harsh winter conditions. This research utilizes data from Harbin and Shenyang, two winter cities in China, to explore the nonlinear influences of subway entrance attributes on passenger satisfaction through the combined use of gradient-boosting decision trees and asymmetric impact-performance analysis. The findings indicate that most key attributes of subway entrances impact passenger satisfaction asymmetrically, highlighting the significance of their hierarchical importance in generating satisfaction. These attributes are categorized into frustrators, dissatisfiers, hybrids, satisfiers, and delighters, based on their asymmetry levels. Considering the current performance of these attributes, the study identifies priority for improvement at Harbin and Shenyang’s subway entrances. This aids urban designers and city managers in making informed decisions for urban development and enhancing the overall commuter experience in winter cities.

Influence of subway entrance layout on indoor and outdoor environments in street canyons with different geometric form

With increasing subway use and in-depth research on pollution associated with subway systems, human exposure to pollutants in metros has received widespread attention. Studies on street pollution, flow fields, and relationships between external pollution and subway entrances have not been fully explored. This study focused on street canyons that contain subway entrances to determine the effects of different street canyon morphologies and subway entrance locations on the pollutants present in the environment. After verifying the feasibility of the software through a neighborhood experiment that applied the ENVI-met model for pollutant dispersion in the canyon, we analyzed the fine particle distribution and wind environment using variable models for streets with different subway entrance locations. The results showed that (1) inside subway entrances, pollution was more severe on the windward than the leeward side; (2) descending street canyon morphology was the most detrimental to air quality inside subway entrances; (3) street canyons rising along the wind direction were most favorable for air quality at pedestrian height inside the neighborhood; (4) at subway entrances located in the street extension direction, the leeward subway entrances had higher particulate matter concentrations at the center of the building, whereas windward subway entrances exhibited higher concentrations near the edge of the building. This study suggested that indoor exposure to pollutants in the subway is sensitive to the layout of entrances in street canyons with different geometries and provides recommendations to improve the layout of subway entrances based on air quality.

Ground Settlement Law, Jacking Force Prediction, and Control Countermeasures for Large-Section Rectangular Pipe Jacking of National Highway Underpass

The rectangular pipe jacking method is an efficient, green, trenchless technology for constructing urban underground space. However, some problems, including the high jacking resistance, the instability of the tunneling face, and excessive ground settlement during the large-section rectangular pipe jacking for the underpass of national highways, seriously affect construction safety and traffic. Based on the engineering background of the large-section rectangular pipe jacking in constructing the subway entrance tunnel of Guangzhou Metro Line 7, this work adopts the methods of theoretical calculation, numerical simulation, and engineering application. Five kinds of mechanical models for pipe soil slurry interactions in rectangular pipe jacking are analyzed. An evaluation of the applicability of the jacking force prediction of the different models is conducted. Moreover, the ground settlement law for the large-section rectangular pipe jacking for the underpass of national highways under different influencing factors, including slurry sleeve thickness, grouting pressure, and earth chamber pressure, is revealed. The control countermeasures of the ground settlements, such as installing a waterproof rubber curtain for the tunnel portal, pipe jacking machine receiving techniques, thixotropic slurry for reducing friction resistance, and soil stability at the tunneling face, are carried out. The results show that there is no need to install an intermediate jacking station in the large-section rectangular pipe jacking project with a jacking distance of 63 m. The most reasonable thickness of the thixotropic slurry sleeve is about 150 mm. The most reasonable grouting pressure range is 600–700 kPa. An earth chamber pressure of about 153 kPa is more reasonable to control the soil stability of the tunneling face. The engineering practice shows that the maximum ground settlement of the national highway during jacking is 10 mm. The maintenance effect is excellent, and the traffic operates normally.

Pedestrian Flows Characterization and Estimation with Computer Vision Techniques

This work describes a straightforward implementation of detecting and tracking pedestrian walking across a public square using computer vision. The methodology consists of the use of the well-known YOLOv3 algorithm over videos recorded during different days of the week. The chosen location was the Piazza Duca d’Aosta in the city of Milan, Italy, in front of the main Centrale railway station, an access point for the subway. Several analyses have been carried out to investigate macroscopic parameters of pedestrian dynamics such as densities, speeds, and main directions followed by pedestrians, as well as testing strengths and weaknesses of computer-vision algorithms for pedestrian detection. The developed system was able to represent spatial densities and speeds of pedestrians along temporal profiles. Considering the whole observation period, the mean value of the Voronoi density was about 0.035 person/m2 with a standard deviation of about 0.014 person/m2. On the other hand, two main speed clusters were identified during morning/evening hours. The largest number of pedestrians with an average speed of about 0.77 m/s was observed along the exit direction of the subway entrances during both morning and evening hours. The second relevant group of pedestrians was observed walking in the opposite direction with an average speed of about 0.65 m/s. The analyses generated initial insights into the future development of a decision-support system to help with the management and control of pedestrian dynamics.

A Demographic Characteristics-Based Study on the Visual Impact Assessment of the External Form of Entrance Pavilions to the Underground Stations of China’s Subway

The subway is one of urban residents’ main means of public transportation. The design of entrance pavilions to subway stations has shown a diverse development trend over time. Since most of the subway building space is underground, it is very difficult for subway users or the public to view the structure fully. In this instance, the ground-level entrance pavilion becomes the most eye-catching element in the subway system. From the perspective of the urban spatial environment, the external form of entrance pavilions is one of the components of urban architecture. The design of the external form of entrance pavilions has an important impact on the urban spatial form and affects people’s feelings about the urban space. Therefore, it is essential to study the external form of entrance pavilions. This study investigated 42 subway entrance pavilions in 17 cities in China. The following features were studied: exterior contour, façade permeability, cultural characteristics, decorative materials, and the number of exterior colors. The photostimulation method was adopted to evaluate the influence of the physical features of the external form of the entrance pavilions on respondents’ visual impact assessment. The data analysis showed that respondents with different demographic characteristics provided different visual impact assessments of the external form of the entrance pavilions, and all five physical features influenced their assessment. This study offers a valuable reference for constructing entrance pavilions and urban spaces in Chinese cities in the future.

Influence of Built Environment on Micromobility–Pedestrian Accidents

The use of micromobility (MM), a form of sustainable urban mobility which has expected effects such as reducing traffic congestion and greenhouse gases, has been rapidly increasing across the world. However, this growth has resulted in a considerable number of MM-related accidents. Most previous studies have explored MM user injuries to improve the safety of MM users, but the threat to pedestrians by MM is not yet fully understood. Therefore, this study aims to identify built environment factors which contribute to MM–pedestrian accidents by using MM–pedestrian crash data in Seoul, Korea from 2020 to 2021. Setting the spatial unit of analysis as a hexagonal grid with an apothem of 150 m, we developed the SZINB (spatial zero-inflated negative binomial) models for the accidents, controlling spatial autocorrelation, zero-inflated, and overdispersion. The model results showed that road intersections, sidewalks, and subway entrances have significant impacts on MM–pedestrian accidents. Thus, it should be suggested that safety measures for both MM and pedestrians are reducing MM speed limits in intersections, preventing MM use on sidewalks through modified sidewalk designs, and installing MM stations near subway stations.

Measuring the associations between eye-level urban design quality and on-street crime density around New York subway entrances

The relationship between crimes, fear of crimes, and the physical environments of metro stations are interlocked. They ultimately influence metro safety and ridership, which are essential for not only urban life quality but also the environmental and fiscal sustainability of regional management. This study mainly investigates how the urban design quality (UDQ) of the ground-level environments surrounding subway stations, both how they express (objectively) and how they are perceived (subjectively), is associated with the reported crime density on streets. To extend conventionally interested ‘broken window theory’, multi-dimensional UDQs highly valued in urban planning literature are measured for metro entrances in New York through the applications of Street View Imagery (SVI), computer vision (CV) and machine learning (ML). Significant associations are found between UDQs and crime densities overbearing the integration of socioeconomic and land use factors. ‘Person’, ‘Safety’ and ‘Complexity’ are associated with higher crime density, while ‘Bench’, ‘Streetlight’, ‘Skyscraper’, ‘Human Scale’, and ‘Imageability’ are related to lower crime risk. By bridging urban planning and criminology literature, this study provides new insights into Crime Prevention Through Environmental Design (CPTED). It contributes to the literature with an efficient approach for urbanists and criminologists to replicate for future studies in microenvironments.

Analysis of air‐inflated rubber dam for flood‐fighting at the subway entrance

AbstractThe air‐inflated rubber dam is innovatively adopted in this paper for temporary flood‐fighting at the subway entrance. Numerical studies using the FLAC2D software are carried out to investigate the behavior of the proposed structure. Laboratory model tests are also conducted to verify the accuracy of the numerical model. The results from the model tests agree well with those from the numerical analysis. Parametric studies are carried out to investigate the influences of the external floodwater head, inflated air pressure, and anchor position on the performance of the proposed air‐inflated rubber dam. It is found that the external floodwater head reduces the tensile force but nonlinearly increases the height of the rubber dam. The inflated air pressure has no obvious effect on the cross‐section of the rubber dam but heavily influences the ultimate flood‐fighting height and tensile force. An optimum design line for the inflated air pressure of the rubber dam is provided. A deeper anchor position results in a smaller ultimate flood‐fighting height. A rubber dam design with a lower anchor depth that has to satisfy the requirements of the anchor bolt is therefore concluded.

The problems of Subway's marketing in the Chinese market and how to improve

As a well-known American fast food brand with thousands of chain restaurants around the world, Subway has many flaws in the process of localizing its brand in China. Through research, we found that Subway's marketing problem in the market is a very serious problem, so the problem of analyzing and improving the marketing strategy of the Chinese market has become the subject of this article. In the survey, this paper first analyzes the inadequacies of Subway's marketing in China from the perspective of consumer psychology and social media and then uses the "swot" model to analyze Subway's current strengths, weaknesses, potential areas, and areas for improvement. Combining the Swot analysis with the analysis of Subway's target customer groups and the analysis of Chinese social media audiences, we make two recommendations. One is to make good use of social media and conduct viral marketing on social media. Secondly, sometimes combined with some hot topics in society, such as "body shame", "worker life" and other hot topics, some derivative activities are carried out to improve the world of subway entrances through these topics.

Analysis of the Degree of Convenience of Xi'an Metro Station

Urban subways have developed rapidly in recent years and has gradually become the primary choice of public transportation in big cities. Subways can effectively alleviate urban traffic congestion and improve passengers’ green travel experience, especially in the old urban areas where urban space is limited, community facilities are aging and historical features are gathered. Subways play a huge role in guiding the expansion of urban space form and improving urban landscape environment. As the only channel for passengers to get in and out of the station, the subway entrance and exit act as a bridge. It is not only the transition space between the subway station space and the urban above ground space, but also an important node for the exchange and circulation of various elements in the urban space. In this paper, the influencing factors of subway entrance and exit space environments in the old city were investigated, and relevant basis for future planning, design, and construction of subway entrances and exits were provided. Firstly, the research results and shortcomings of subway entrance and exit channels were outlined. Secondly, based on the perspective of residents and passengers, this paper uses the analytic hierarchy process to determine six first-class evaluation indexes, including safety, convenience, practicability and aesthetics. This paper constructs the evaluation system of spatial environment index of subway station entrances and exits in the old urban area of Xi’an. Lastly, according to the evaluation results, the paper puts forward the targeted optimization strategies for the current situation of the entrance and exit space environment of the subway stations in the Xi’an.

Study on the Current Situation of Urban Integration of Aboveground Space and Underground Space: Under the Background of China’s Land Spatial Planning

Urban underground public space has a synergistic effect with its surrounding urban aboveground functions or facilities, which reflects the complementarity between underground functions and urban functions. The research analyses the degree of integration through the case study of urban aboveground space and underground space in China. The research method of this paper will give different evaluation criteria to public transport and public space and the influencing factors of space integration. The indicators of public transport include the number of subway lines and underground parking spaces. The evaluation standard of public space is the area of underground space and the number of floors of underground space. The subway entrance and exits are selected as the evaluation index for the aboveground and underground transition space. Through the specific analysis of 7 selected cases, it provides arguments for the research. The average rent in the case is taken as the dependent variable. Through the regression model, the influencing factors of the integration of aboveground and underground space are determined. The purpose of the study is to explore the influencing factors of the integration of aboveground space and underground space, and how to optimize the integration of aboveground and underground space

Study on the Current Situation of Urban Integration of Aboveground Space and Underground Space: Under the Background of China’s Land Spatial Planning

Urban underground public space has a synergistic effect with its surrounding urban aboveground functions or facilities, which reflects the complementarity between underground functions and urban functions. The research analyses the degree of integration through the case study of urban aboveground space and underground space in China. The research method of this paper will give different evaluation criteria to public transport and public space and the influencing factors of space integration. The indicators of public transport include the number of subway lines and underground parking spaces. The evaluation standard of public space is the area of underground space and the number of floors of underground space. The subway entrance and exits are selected as the evaluation index for the aboveground and underground transition space. Through the specific analysis of 7 selected cases, it provides arguments for the research. The average rent in the case is taken as the dependent variable. Through the regression model, the influencing factors of the integration of aboveground and underground space are determined. The purpose of the study is to explore the influencing factors of the integration of aboveground space and underground space, and how to optimize the integration of aboveground and underground space

Influences of the optimized air curtain at subway entrance to reduce the ingress of outdoor airborne particles

It is of great significance to control the air quality of underground metro stations, especially considering their poorly ventilated environments. Existing literature mainly focuses on the removal and control of underground pollutants and seldom pay attention to the ingress effects of atmospheric pollutants (e.g., from the burning of fossil fuels, exhaust gas of vehicles, etc.) diffusion through the entrances/exits. In this study, we aim to study the reducing effects of integrated air curtain and exhaust systems on atmospheric airborne particles entering into the metro stations. Validated turbulent models were adopted for numerical simulations. The associated effects of air curtain velocity, exhaust velocity, and atmospheric wind speed were investigated. Four different installation locations of the air curtain were considered. Subsequently, monitoring, Artificial Neural Network, and air purification methods were proposed for the optimal design of integrated air curtain and exhaust system. It is concluded that an integrated air curtain and exhaust system can improve the interception efficiency on particles around 40% compared with no measure taken at the subway entrance, or it can be increased about 20% compared with only using an air curtain system (no exhaust vent) at the entrance.

Factors influencing the access duration of free-floating bike sharing as a feeder mode to the metro in Shenzhen

In recent years, free-floating bike sharing (FFBS) has become an effective travel mode to connect the urban rail transit in the first/last mile. However, access duration, a significant factor for integrating bike and metro systems and improving the connecting efficiency, has received little attention from scholars. To fill this gap, the goal of this study is to identify the factors that affect the access duration of FFBS as a feeder mode to and from metro stations. Using operation data of FFBS in Shenzhen, China, we first explore the spatiotemporal characteristics of access duration in core area and suburb. Then, the influences of built environment, public transport services, travel attributes, temporal characteristics, and meteorological conditions on access duration for these two areas are examined using multinomial logistic models. The results indicate that: (1) access duration during the morning peaks on weekdays is shorter than that in the evening peaks and on weekends. The proportion of short access duration trips (1∼7min) among all access trips in the core area is higher than that in suburb. (2) For weekdays, more major roads increase access duration, while more branch roads would decrease it, especially in the core area. An increase in the number of subway entrances and exits significantly reduces access duration in the suburb. And the number of road intersections and congestion level in the cycling environment increase access duration, especially in the core area. (3) For weekends, the built environment has a weak impact on access duration, and higher levels of congestion in the cycling environment increase access duration, but the effect is smaller than that on weekdays. (4) Unexpectedly, the length of bicycle lanes has no significant effect on shortening access duration. Finally, elasticity analysis is carried out to identify effective policies for improving access efficiency, such as constructing branch roads in core area, improving the quality and the cycling environment of the bicycle lanes, reasonably increasing the number of subway entrances in suburb.

Analysis of the influence of subway entrance excavation on tunnel and adjacent buildings

With the rapid development of urban subway transit construction, the construction of subway entrance and exit accessory structure in densely populated areas and near buildings is gradually increasing. Based on the open-cut foundation pit project at the entrance and exit of subway R3 line in Jinan city, this paper adopted MADIS GTS/NX 3D finite element analysis software to conduct finite element analysis on the connection tunnel and adjacent buildings by subway entrance and exit foundation pit excavation, and analyzed the displacement change trend of foundation pit excavation on the underground tunnel and building. The results show that the horizontal displacement of the connection area between the tunnel and the foundation pit is small, while the vertical displacement of the tunnel is relatively large, with a maximum value of 3.58mm. The settlement at the corner of the building adjacent to the foundation pit is relatively large, and the maximum settlement value is 3.03mm. It is in good agreement with the measured data and meets the requirement of deformation control. This study provides reference for the foundation pit engineering of subway entrance and exit of similar adjacent buildings.

A Study on the Design of Subway Entrance Facilities in Universal and Affordance Viewpoints - Focusing on the Behavioral Supportability of the Elderly -

A Study on the Design of Subway Entrance Facilities in Universal and Affordance Viewpoints - Focusing on the Behavioral Supportability of the Elderly -

레이아웃의 원리를 기반으로 민방위 대피시설 표지판 유형 및 부착 위치의 특성에 관한 연구 - 서울 지하철 노선 지하출입구를 중심으로 -

레이아웃의 원리를 기반으로 민방위 대피시설 표지판 유형 및 부착 위치의 특성에 관한 연구 - 서울 지하철 노선 지하출입구를 중심으로 -

China Research Status of Ground Landscape Design for Subway Entrances and Exits

Main domestic documents about subway entrance landscape design has been analyzed. It has been concluded that subway entrance landscape concept, interaction of subway entrance and surrounding landscape, common features and individual features of subway entrance landscape, elements of subway entrance landscape, design strategies and design principles of subway entrance landscape, the optimization strategy for subway entrance landscape, subway entrance landscape element comment system establishing. And the research direction in the future has been raised.

Analysis of unsteady airflow in a subway station influenced by train movement

The piston effect has a significant effect on ventilation systems in subway stations. In this article, experimental data and computational fluid dynamics (CFD) methods are used to examine the behavior of the unsteady airflow generated by train movement. The experimental data recorded in an actual station in the Tehran subway and a full-scale model were used for the numerical simulation. The simulation was conducted using layering method to simulate the train movement through the tunnels and station according to the actual subway train velocity trend. Air curtains were used to reduce the undesired influence of the piston effect in the station and increase the efficiency of the ventilation system. The results indicated that maximum amplitude of air velocity at the subway entrance caused by the train movement can be reduced 67% by using an air curtain on the subway platform.