Subway Accident Research Articles

Lessons and improvements: Subway waterlogging catastrophe in Zhengzhou, China

The cause of major accidents provides valuable lessons for hazard prevention and management improvement. However, the investigation of major accidents in a social-technical system could be a challenge that requires inter-disciplinary approaches. Accimap, a system-oriented method in accident investigation, has been widely used around multiple industries. However, as a typical social-technical system with various internal and external interactions, system-oriented analysis has rarely been applied in subway systems. Therefore, the objective of this work is to enhance the Accimap framework to conduct a hierarchical investigation into the contributions of multiple factors to the Zhengzhou waterlogging accident and analyze the interconnections between factors during the accident’s progression. To capture the multiple-stage characteristic of subway accidents, a sub-system concept is introduced. By studying the accident evolution in depot/construction subsystem, station/dispatch subsystem and tunnel/rescue subsystem, this work provides a detailed case study that reveals the underlying deficiencies in the emergency management of Chinese subway system. Besides, this work also reviewed the most important countermeasures and policies implemented by different levels of governments following the accident. By demonstrating the lessons learned from and improvements made after the major accident, the findings can support the accident prevention and policy making within the subway industry in the future.

Determining Subway Emergency Evacuation Efficiency Using Hybrid System Dynamics and Multiple Agents

With the rapid development of the city, more and more people are choosing the subway as their travel mode. However, the hidden dangers of the subway are becoming increasingly prominent, and emergency evacuation of the subway has become a key factor for its safe operation. Therefore, the research objectives of this paper were to focus on the subway emergency evacuation hybrid model to fill the gap in the field of emergency evacuation simulation methods and countermeasure optimization. The analysis network process (ANP) was used to analyze the influence factors and weights of subway pedestrian evacuation. On this basis, a multiagent model of subway pedestrian evacuation (SD + multiagent) was developed and simulated. The results show that the comprehensive evacuation strategy could improve the evacuation efficiency, shorten the evacuation time, and avoid the waste of resources. This study not only improved the accuracy of the simulation, but also clarified the evacuation process. This approach can effectively prevent the occurrence of subway accidents, reduce casualties, and prevent large-scale casualties such as secondary accidents (induced secondary disasters).

A Causation Analysis of Chinese Subway Construction Accidents Based on Fault Tree Analysis-Bayesian Network.

Clarifying the causes of subway construction accidents has an important impact on reducing the probability of accidents and protecting workers’ lives and public property to a greater extent. A total of 138 investigation records of subway construction accidents from 2000 to 2020 were collected in this study. Based on a systemic analysis of 29 well-known accident causation models and the formative process of the subway construction accidents, we extracted the causative factors of subway construction accidents from the collected records. Furthermore, a causation analysis index system of subway accidents was proposed based on fault tree analysis (FTA), where we considered subway construction accidents as the top event and the five dimensions, i.e., human, equipment, environment, management, and safety culture, as first-level intermediate events. Moreover, 17 causative factors were considered to be related to the severity of subway construction accidents. It is found that human factors are prone to be critical to high-risk accidents. Finally, a Bayesian network (BN) was formed to explore the causative factors of high-risk subway construction accidents. Based on the combined application of FTA and BN, this study discusses the complex influence factors and their action routes to unsafe accidents in subway construction sites, and makes efforts to correspond safety decision basis for the management of China subway construction.

Metro station evacuation safety assessment considering emergency response

The emergency response process will not start immediately in the initial stage of a subway accident, and information will not fully spread temporarily. Crowds in different regions receive different comprehensiveness of accident information. They will start evacuating at different times and at different desired speed states. Depending on this phenomenon, pedestrians were classified in simulation modeling. In addition, the different states of emergency gates, escalators, and automatic gate machines before and after the emergency response instruction were set up in the simulation. The impact of different emergency response times on evacuations was studied. The emergency response in advance did not make a significant promotion to evacuation efficiency, but delayed emergency response reduced it greatly. This work proposed an evacuation risk index (ERI) and maximum safe evacuation capacity in metro stations. The worst accident evacuation scenario can be obtained by calculating the ERI, and a metro station was evaluated as a case study. The comparison of the evaluation results of ERI and other methods shows that the conclusion is consistent, but ERI considers the accident location factor.

A Study on the HUMAN PSYCHOLOGICAL Stability of Railroad Engineers after an Accident

Trains running through urban railroad sections in large cities are an important means of transportation for many passengers. In 2019, the number of passengers using the Seoul Metropolitan Railway reached 2.9 billion. The drivers are responsible for the safe operation of the numerous passengers repeatedly go two to three minutes apart, looking only at the railroad tracks in the dark underground section. Although the urban railway system is becoming state-of-the-art and accidents are caused by system errors and human error continue, so the train drivers must exert a high level of concentration to prevent accidents. This professional nature has led to consid-erable job stress for drivers, and the annual subway accident is feared to cause depression, bipolar disorder, obsessive compulsive disorder, and various mental disorders and panic disorder caused by post-traumatic stress disorder. In this paper, while the accident lessons and measures are active in railway operation institutions after the occurrence of various railway accidents, the measures for drivers have been taken away from the very insuf-ficient existing methods and considered the engineer as a special class of high-risk groups, and the application of the psychological stability program of firefighting officials, who are currently high-risk. The meaning and neces-sity of developing human psychological stability program for railroad engineers were presented by analyzing these.

Research on Risk Control of Subway Operation System Based on Vulnerability Analysis

With the increasing importance of the subway in the urban rail transit system, it is the primary task to ensure the safe operation of the subway by studying and analyzing the vulnerability of the subway operation system to strengthen the operation risk control of the subway. By combing the concept of risk and vulnerability, the paper concludes that vulnerability includes three factors: exposure degree, sensitivity degree and adaptable degree, and based on the AHV analysis framework, the evolution mechanism of subway system vulnerability is presented. According to the different influence and effects of different types of vulnerability in the accidents, a series of typical subway accident cases at home and abroad are analyzed and the vulnerability risk control model is established.

Investigation of the Probability of a Safe Evacuation to Succeed in Subway Fire Emergencies Based on Bayesian Theory

Emergency evacuation in subway fires is one of the hot issues in public safety. Based on Bayesian theory, a dynamic evacuation risk analysis model considering both psychological and behavioral responses of evacuees was proposed in this contribution. A subway fire scene was modeled using the Event Tree Analysis (ETA) according to the questionnaire survey at Nanjing Xinjiekou station. In this fire scenario, three control events (the fire alarm, the exhaust system and the evacuation route) were related to fire evacuation control and two control events (active escape and passive escape), which were specifically defined, were related to personnel characteristics. Subsequently, the probability of the final state of each scene was calculated by Monte Carlo simulation. Combined with the statistics of accidents and safe evacuation of subway fire cases from 1976 to 2013, the posterior probability distribution of safety evacuation was obtained after real-time dynamic updating of its precursor probability through Bayesian theory. Results show that the posterior probability of safety evacuation to succeed is around 0.8. This indicates that there is still a probability of 0.2 resulting in injury or fatalities in subway accidents even though most passengers are safely evacuated. It also suggests that utilization of 0.2 as the safety threshold would be an appropriate choice.

Causal Analysis to a Subway Accident: A Comparison of STAMP and RAIB

Accident investigation and analysis after the accident, vital to prevent the occurrence of similar accident and improve the safety of the system. Different methods led to a different understanding of the accident. In this paper, a subway accident was analysed with a systemic accident analysis model – STAMP (System-Theoretic Accident Modelling and Processes). The hierarchical safety control structure was obtained, and the system-level safety constraints were obtained, controllers of the physical layer were analysed one by one, and put forward the relevant safety requirements and constraints, the dynamic analysis of the structure of the safety control is carried out, and the targeted recommendations are pointed out. In comparison with the analysis results obtained by the Rail Accident Investigation Branch (RAIB). Some useful findings have been concluded. STAMP treats safety as a control problem and reduces or eliminates causes of the accident from the controlling perspective. Whereas RAIB obtains causes of the accident by analysing the sequence of events related to the accident and reasons of these events, then chooses one(or more)event(s) as the immediate cause and some of the key events as causal factors. RAIB analysis is based on the sequential event models, but STAMP analysis provides us with a holistic, dynamic way to control system to maintain safety.

The Application of Multi-Agent in Emergency Events of Metro Station

The question of metro safety is one of the hot areas of current research. Subway accident will not only cause a lot of casualties, but also caused widespread traffic jams, to which is very important to pay close attention. Through the analysis of potential safety hazard of metro interchange station and the distinguishing feature of the technology of multi-agent, this thesis pose a new application of multi-agent in emergency events of metro station.

FDS를 이용한 지하철 객실 화재 시 승강장 제연조건의 적정성 평가

지하철에서는 전 세계적으로 크고 작은 화재가 지속적으로 발생되고 있다. 대구지하철 화재에서 볼 수 있듯이 독성가스와 연기에 의한 가시거리 감소로 많은 인명피해가 발생하였다. 본 논문에서는 부산 지하철 만덕역에서 열차 화재가 발생할 경우 승강장에서의 제연상황(열차문의 개방, 터널의 제연설비의 가동, 방화문의 작동)에 따라 연기의 전파거동을 FDS를 사용하여 분석하였다. 계산 결과 터널부의 제연설비를 가동하였을 경우보다는 가동하지 않았을 경우가 피난로 확보에 효과가 있었다. 또한, 열차문의 개방 형태는 승강장의 대피로 측의 문은 모두 개방하고 화재객차의 선로측 문만을 개방하였을 경우가 모두 개방한 경우보다 제연 효율이 증가하는 것을 알 수 있었다. 또한, 승강장의 방화문이 정상적으로 가동하는 것이 중요하다는 것을 알 수 있었다. In the subway, various fires continue to take place across the world. In the Daegu subway accident in 2003, many people were damaged by shortened visibility range caused by toxic gas and smoke. This paper, assuming that a subway fire happens in the Mandeok Station of the subway system in Busan, analyzed different smoke-spreading situations depending on the ventilation situation at its platform (opening of the train doors, operation of ventilation facilities in the tunnel, and working of fire door), using FDS. The calculation proved that it would be more effective to secure evacuation route when the ventilation facilities of the tunnel are not operated, than when they are on. And, it was also found that the case where the doors of the platform to the escape route and only the platform-facing doors of the subway car on fire office are open would be more effective to ventilation than the case where all the doors are open. And, it was found to be important that the fire doors of the platform are working properly.

Study on Subway Safety Measures and Emergency Rescue’s Countermeasures in Shenyang

With the development of global urbanization, the development of underground rail traffic network is imperative, and the subway has become a convenient and effective traffic tool to solve people’s trip. While the subway accidents happen constantly, so the subway emergency rescue has become an important event to related departments. This paper firstly analyzes the main types and characteristics of subway emergencies, and concludes some main emergency countermeasures.

Devastating Consequences of Subway Accidents: Traumatic Amputations

The efficiencies of the subway system are tempered by the occurrence of accidents, some with devastating injuries. The purpose of this study is to examine our experience with traumatic amputations after subway accidents. A retrospective trauma registry review (1989-2003) of 41 patients who presented to Bellevue Hospital, New York City, with amputations from subway accidents was undertaken to examine the following end points: age, sex, Injury Severity Score, time and mechanism of accident, history of psychiatric disorders and alcohol use, admission vital signs, Glasgow Coma Scale score, amputation type, associated injuries, limb salvage rate, operative procedures, mortality, and disposition. Elevated alcohol levels and prior psychiatric diagnoses were present in 39 per cent and 17 per cent of the patients, respectively. Patients were stable on admission with a mean systolic blood pressure of 114 mmHg, hematocrit of 32, and Glasgow Coma Scale score range of 13 to 15. The most common amputation was below knee, and patients underwent an average of three operative procedures. Limb salvage was attempted in eight patients with no successes. Amputation wound infection rate was 32 per cent and mortality rate was 5 per cent. Victims of subway trauma who arrive at the hospital with devastating amputations have an excellent chance of surviving to discharge.

Effects of a Simulated Subway Accident on the Emergency Room of a Hospital

Effects of a Simulated Subway Accident on the Emergency Room of a Hospital