|
|
ENQUIRE PROJECT DETAILS BY GENERAL PUBLIC |
| Project Details |
| Funding Scheme : | General Research Fund | ||||||||||||||||||||||||||||||||||||||||||||||||
| Project Number : | 119011 | ||||||||||||||||||||||||||||||||||||||||||||||||
| Project Title(English) : | On the use of agent-based modeling approach for studying tunnel egress in mass transit system | ||||||||||||||||||||||||||||||||||||||||||||||||
| Project Title(Chinese) : | 基于个体建模的地铁隧道疏散研究 | ||||||||||||||||||||||||||||||||||||||||||||||||
| Principal Investigator(English) : | Prof Lo, Siu-ming | ||||||||||||||||||||||||||||||||||||||||||||||||
| Principal Investigator(Chinese) : | |||||||||||||||||||||||||||||||||||||||||||||||||
| Department : | Department of Architecture and Civil Engineering | ||||||||||||||||||||||||||||||||||||||||||||||||
| Institution : | City University of Hong Kong | ||||||||||||||||||||||||||||||||||||||||||||||||
| E-mail Address : | bcsmli@cityu.edu.hk | ||||||||||||||||||||||||||||||||||||||||||||||||
| Tel : | 3442 7683 | ||||||||||||||||||||||||||||||||||||||||||||||||
| Co - Investigator(s) : |
|
||||||||||||||||||||||||||||||||||||||||||||||||
| Panel : | Engineering | ||||||||||||||||||||||||||||||||||||||||||||||||
| Subject Area : | Civil Engineering, Surveying, Building & Construction | ||||||||||||||||||||||||||||||||||||||||||||||||
| Exercise Year : | 2011 / 12 | ||||||||||||||||||||||||||||||||||||||||||||||||
| Fund Approved : | 817,500 | ||||||||||||||||||||||||||||||||||||||||||||||||
| Project Status : | Completed | ||||||||||||||||||||||||||||||||||||||||||||||||
| Completion Date : | 30-6-2015 | ||||||||||||||||||||||||||||||||||||||||||||||||
| Project Objectives : |
|
||||||||||||||||||||||||||||||||||||||||||||||||
| Abstract as per original application (English/Chinese): |
The mass transit system in Hong Kong carries over 3.7 million passengers everyday. With the rapid development of the community, its network has been extended over the years. New lines in the territory and connection to the Mainland are constructed. While the system is carrying huge volume of passengers per day, the safety of passengers in case of fire and emergency is one of the major concerns of the mass transit company as well as the government. The operator has endeavored to avoid accidents to happen in the system, yet zero risk situation cannot be guaranteed. To mitigate the ill-effect of an accident, provision of an efficient egress system is necessary. The design of fire and emergency egress system usually refers to the Guidelines prescribed by NFPA130 - Fixed Guideway Transit and Passenger Rail Systems for tunnel emergency egress provisions. The 2010 edition of the standard denotes that "emergency exits shall be provided from tunnels to a point of safety" and that "within underground or enclosed trainways, the maximum distance between exits shall not exceed 762 m. In view of the complex urban topography and existing building configurations, the orientation and design of tunnels for the subway system can be restrictive and the prescriptive guidance in NFPA130 can sometimes hardly be met and performance evaluation may sometimes be required in order to obtain the approval from relevant government authorities. Fire safety strategies are established for the design and operation of each line. However, the performance of the strategies, in view of the complexity of the system, may not be objectively evaluated in all aspects. The aim of this proposal is to develop an agent-based egress model to explore the evacuation pattern of evacuees in rail tunnels and associated facilities. The simulation results can be adopted to evaluate the effectiveness of different tunnel egress design and assist the establishment of trackside emergency egress strategies. It can also provide insight for the design of smoke extraction and formulating appropriate means of access for firefighting and recue strategies. 由于近年不断发展，香港地铁网络延伸到新界各地。每天乘客量超过3百多万，乘客和地铁人员在紧急情况的安全极为重要。香港地铁公司积极确保安全，但我们清楚明白绝对的安全是不能达到。也不可能完全避免意外的发生。在紧急情况下有时候需要把地铁内乘客和人员疏散。传统上地铁的紧急疏散是参考美国NFPA130的标准设计。如在隧道内最远疏散距离为762米。但在复杂的城市环境，有时候不一定能达到这处方式的标准。这时性能化设计有需要考虑。本研究是开发基于个体的隧道疏散模型，提供模拟工具对隧道疏散设计进行评估，同时也可以对疏散策略进行优化。 |
||||||||||||||||||||||||||||||||||||||||||||||||
| Realisation of objectives: | Five objectives were proposed and they had basically been addressed. (1) Problems of evacuation strategies for rail tunnels and the associated facilities were reviewed and identified. In particular, review on the cross-passage requirements given in NFPA130 and other fire safety codes have been made. Computer simulation modeling has been proved as a powerful tool to address this kind of problems. In fact, evacuation modeling has been studied for many years so far, and large number of simulation models has been developed to modeling the movement of people under various kinds of environment conditions. Based on the methods of representing and discretizing of the floor plan or the time, these models have usually been categorized into continuous models and discrete models. In continuous models, such as the Agent-based model (ABM), people are allowed to move at any directions in a continuous represented space, while in discrete models, such as the Cellular Automaton model (CA), the floor plan are discretized into regularly distributed grids and people are only allowed to move from one grid to another. Both of these two kinds of models are proved to be qualified to reproduce many crowd movement behaviors, and to some extent, their simulation abilities are even proved to be similar with each other, but both of them are also criticized for some of their flaws. Efforts have been made to analyze the effectiveness of using different types of simulation models, CA or ABM, for modeling the evacuation pattern in rail tunnel and stations. [Ref. Part C, 9 (1)]. To improve the simulation outputs, the team has commissioned to develop a comprehensive ABM – CityFlow and the details of the model have been published. Two PhD students were trained for the development of the ABM. [Ref. Part C, 10 (1) & (2)]. (2) An agent-based egress model to simulate various tunnel evacuation processes and pedestrian movement pattern was established. Simulations have been adopted to analyzing the effect of codes requirements on the escape process. [Ref. Part C, 8 (2)]. As evacuation process would link to the escape process in stations, the works were extended to study the effectiveness of various evacuation strategies for the system including evacuation process in metro stations and the pedestrian moving patterns in stations. [Ref. Part C, 8 (8) & (9)]. The agent-based pedestrian movement model—CityFlow was developed and adopted for the simulations [Ref. Part C, 8 (3), (6) & (7)]. The tool has been demonstrated that it is useful for evaluating the performance of different alteration proposals and to study the fire escape process. In particular, we proposed the concept of ‘transit line’ to make the egress as a whole instead of targeting at single level, leading to more practical simulation results. Moreover, the dynamic density maps were prepared on the basis of the simulation outputs which could provide certain implications to the designers/ architects, and valuable insights to facility manager to plan the emergency evacuation and rescue strategies. In future study, we will further develop the model by optimizing the egress route assignment. (3) A comprehensive evacuation drill exercise in associate with the Hong Kong Mass Transit Corporation (MTRC) was arranged on November 19th, 2014 at Mongkok Station. Over 2,000 participants have been arranged to take part in the evacuation drill exercise. RFID cards were issued to the participants to record their dynamic positions during the escape process. Videos, on-site counting and after-exercise questionnaire survey information have been collected. Data and other information were collected and reported to MTRC, and had been used to compare with the simulation outputs. (4) Computer simulations were performed to evaluate the effectiveness of various fire safety design for rail tunnel and stations strategies. Moreover, studies on various aspects of pedestrian movement were also carried out. This includes studies on the bidirectional movement of people, people movement on gradient road, next-nearest-neighbor effect on people’s movement, people movement on crowd-quakes and etc. [Ref. Part C, 8 (1), (4), (5) & (10)]. Such works would be useful for future studies on evacuation process involving movement of people. (5) The findings were published and disseminate in some conferences and talks to international and local fire safety professionals and fire officers. In particular, part of the works were collaborated with MTRC and the information was recorded by them for future usage. Further analysis to the evacuation drill exercise is undergoing and will soon be published subject to MTRC agreement. | ||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of objectives addressed: |
|
||||||||||||||||||||||||||||||||||||||||||||||||
| Research Outcome | |||||||||||||||||||||||||||||||||||||||||||||||||
| Major findings and research outcome: | The NFPA 130 standard has given limited suggestions on the design of means of egress in rail tunnels. In this study, an agent based continuous crowd simulation model, CityFlow, was developed to study the evacuation from rail tunnel with cross-passageways. [Ref. Part C, 8 (3), (6) & (7)]. We initially focused on the influence of the walkway width and cross-passageway spacing on the egress time and queuing patterns during the evacuation. We found that if the width of walkway was added by every 100 mm, the egress time would decrease accordingly, but with different sensitivity at different width. [Ref. Part C, 8 (2) & 9 (1)]. The continuous model was proved to be eligible for identifying the continuously change of the dimensions of egress element. The study also revealed that the distance between cross-passageways was highly relevant to the optimized evacuation route choice strategy and certainly was an important parameter for egress time. Studying evacuation process from tunnel linked to the escape in stations. Indeed, the evacuation pattern is more complicated in large complex stations, especially when shopping and other facilities exist in the stations. We have further developed the agent-based model to simulate people movement in stations and the corresponding behavioral responses. [Ref. Part 8, (3), (6), (7), (8) & (9)]. To further investigate the movement characteristics of people under normal and emergency situations, other words relating to pedestrian movement, such as bidirectional flow in various conditions and crowd-quakes, have been initiated. [Ref. Part 8, (1), (4), (5) & (10)]. The density and population loading on each metro station may have significant effect on evacuation strategy in case of emergency. The metro company has comprehensive data collected from the automatic fare system. Works have been initiated to study how the automatic fare collection record may affect the metro trip pattern of people. [Ref. Part C, 8 (11)]. This provides insight on the population level of metro stations at various period of time and, in turn, provides valuable information for emergency mitigation planning. | ||||||||||||||||||||||||||||||||||||||||||||||||
| Potential for further development of the research and the proposed course of action: |
Guaranteeing a safe, efficient, and comfortable traveling system for passengers and other users is one of the most important aspects of an intelligent rail transportation system. Microscopic simulation of passenger flow in rail system may initiate insights that greatly benefit engineers and operators in the planning and management of the system. In this research, an agent-based microscopic pedestrian flow simulation model, CityFlow, has been developed. The building floor plan in the model is represented by a continuous space constructed in a network approach, and each pedestrian is regarded as a self-adapted agent. Agent movement is implemented in a utility maximization approach by considering various human behaviors. The influences of parameters in the model on the simulation results are investigated. Typical pedestrian flow phenomena, including the unidirectional and bidirectional flow in a corridor as well as the flow through bottlenecks, can be simulated. The model outputs have been validated by field data. The simulation results can serve as a good basis for the design and management of facility setting in mass transit systems. It can also be applied for the design and planning of complex buildings, urban layout and many facilities such as passenger ships, aircraft and etc. | ||||||||||||||||||||||||||||||||||||||||||||||||
| Layman's Summary of Completion Report: | To study the evacuation from rail tunnels is vital for saving human lives when trains are forced to stop inside the tunnel in case of emergency. Although NFPA130 standard has guided the design of means of egress in rail tunnels, very rare other references can be found about the tunnel evacuation. In this research, an agent based continuous crowd simulation model, CityFlow, was developed to study the evacuation from rail tunnel with cross-passageways. The study has initially focused on the influence of the walkway width and cross-passageway spacing on the egress time and queuing patterns during the evacuation. The simulation results have revealed that if the width of walkway was added by every 100 mm, the egress time would decrease accordingly, but with different sensitivity at different width. Such simulation model can identify the continuously change of the dimensions of egress routes. The study also revealed that the distance between cross-passageways was highly relevant to the optimized evacuation strategy and was an important parameter for egress time. The simulation model has further applied to study the passenger movement and evacuation pattern in stations. Moreover, the model can also be applied to study pedestrian movement in complex urban and building settings. | ||||||||||||||||||||||||||||||||||||||||||||||||
| Research Output | |||||||||||||||||||||||||||||||||||||||||||||||||
| Peer-reviewed journal publication(s) arising directly from this research project : (* denotes the corresponding author) |
|
||||||||||||||||||||||||||||||||||||||||||||||||
| Recognized international conference(s) in which paper(s) related to this research project was/were delivered : |
|
||||||||||||||||||||||||||||||||||||||||||||||||
| Other impact (e.g. award of patents or prizes, collaboration with other research institutions, technology transfer, etc.): |
Collaboration with Hong Kong Mass Transit Rail Company for data collection and evacuation drill exercise. In particular, a comprehensive evacuation drill exercise in associate with the Hong Kong Mass Transit Corporation (MTRC) with the assistance of several government departments including Hong Kong Fire Services Department, Hong Kong Buildings Department, Hong Kong Police and etc, was arranged on November 19th, 2014 at Mongkok Station. Over 2,000 participants have been arranged to take part in the evacuation drill exercise. Videos, on-site counting and after-exercise questionnaire survey information have been collected. Data and other information were collected and reported to MTRC. | ||||||||||||||||||||||||||||||||||||||||||||||||
| SCREEN ID: SCRRM00542 |