Research On Assessing The Vulnerability Of Beijing Urban Rail Transit Network Operation System Against Fire Disturbance

In order to alleviate traffic congestion,Beijing has accelerated the development of urban rail transit system in recent years,and in 2008,initially realized the transformation of rail transit operation from a traditional single-line management model to a network model.With the continuous expansion of the operating mileage and scale,Beijing is facing more complex operation and management pressures such as increasing passenger flow,increasing transfer stations,and more units participating in operation.In order to ensure the travel safety of the capital citizens and maintain orderly operations and social stability,it is necessary to study the vulnerability of the network operation system as a complex and large-scale risk carrier,which can improve the quality and efficiency of continuous development of network operation,lower the operation accident risk,and provide reference for the construction of other urban rail transit operation system.Firstly,the system vulnerability theory is summarized,including the concept of vulnerability,the three-element theory,the successive evolution,and the vulnerability assessment method.Then,the current situation of the Beijing urban rail transit network operation is studied,from the operation organization,the operation business,and the emergency response and other aspects,and the reason of existing system vulnerability is analyzed.Since fire is one of the threatening factors that causes heavy casualties in rail transit system,the system vulnerability research on fire disturbance conducted.To find the vulnerability elements leading to fire effect,the vulnerability theory is applied to analyze the cases of fire emergency in Beijing urban rail transit system.Based on the above research,literature analysis,case analysis,on-site survey,expert interviews,and other methods are used to summarize vulnerability elements focusing on business specialty,and a vulnerability assessment index system model for the network operation of Beijing urban rail transit under fire disturbance is build.The index system has a four-layer structure,and is first decomposed into four subsystems: traffic organization,passenger service,power supply,and environmental control according to the main operation business of the assessment object.Then,the index system is decomposed layer by layer from the other two dimensions,the three elements of vulnerability and the system components of accident causes,which totally constitute111 four-level indexes finally.The AHP analytic hierarchy process and fuzzy comprehensive analysis method are used to carry out an empirical study on the vulnerability assessment of the index system model.The research shows that using the constructed index system to perform the system assessment,can not only find out the key factors that lead to the vulnerability of Beijing urban rail transit network operation against fire disturbance,but also quantify the vulnerability degree of each business subsystem and the whole network operation system.From this,recommendations to decrease the vulnerability of specific operating business segments can be also made.The above research results will support network operation to coordinate relevant operation departments of total system based on business needs to continue tracing and controlling system vulnerability level in response to fire disturbance.