Research On The Disaster Chain Evolution Model And Risk Assessment Of Urban Rail Transit

Urban rail transit is an important component of urban public transportation in China.Due to its advantages of large traffic volume,speed,environmental protection,safety and punctuality,it has become one of the most important means of transportation for residents in major cities in China.However,since the opening of urban rail transit at home and abroad,it has been affected and damaged by various disasters during its operation,such as floods,fires,terrorist attacks,equipment failures,and other disasters.Urban rail transit disasters are prone to evolve into chain reactions,weakening the safety,speed,and punctuality of urban rail transit,causing huge losses to the safety of passengers’lives and property,and also seriously causing adverse social impacts.Therefore,in order to improve the efficiency and safety of rail transit operations and reduce the risks brought about by disaster chain reactions,this article will combine complex network theory to build a disaster chain network model for urban rail transit and conduct risk assessment on it.For high-risk disaster chains,different strategies for disaster chain reduction are proposed from the stage of disaster chain incubation and development.Through comprehensive application of literature analysis,text mining,knowledge element theory,and cases-based reasoning,this study collected and sorted out 587historical cases of urban rail transit disasters at home and abroad.Based on this,visual analysis was conducted according to the type of disaster chain and disaster type time,to analyze the occurrence rules of the rail transit disaster chain.Then,based on the theory of complex networks,a rail transit disaster chain network model is constructed based on historical disaster chain cases of rail transit,and the topological structure characteristics of the disaster chain network are analyzed.Based on this,a risk assessment model for rail transit disaster chain is constructed by comprehensively considering the topological structure and transmission characteristics of the complex disaster chain network.Finally,take the rail transit rainstorm disaster chain as an example to conduct empirical analysis,build the rail transit rainstorm disaster chain network model,calculate the risk probability,risk loss and edge vulnerability of the rainstorm disaster chain,and conduct risk assessment.According to the research results,the disaster path of rail transit disaster chain is short in the transmission process,and there is a high clustering effect between disaster event nodes.The transmission follows a certain randomness and has the characteristics of small-world network.Among them,in the process of rainstorm disaster chain transmission,the risk assessment value of station waterlogging disaster chain caused by edge e(v₁,v₃₄)rainstorm is the highest,which is 10.023,far higher than the risk of other disaster chains in the network.