Chain Transfer Model And Risk Analysis Of Metro Disaster Chain Based On Complex Network Theory

This paper takes the urban rail transit system as the research object.It adopts various research methods such as field research,theoretical analysis,computer modelling and engineering verification to conduct a comprehensive study on the network characteristics,chain transmission of disaster chains and the risk probability of disaster occurrence in the urban rail transit system.The research content of this paper is divided into the following aspects,and the corresponding research results are obtained.(1)The summary method collects nearly 100 subway disaster cases at home and abroad.The paper analyzes the distribution characteristics,inducing factors and disaster mechanism of various subway disaster events using accident cases and classifies the subway operation accidents.It is concluded that the subway operation accidents are mainly concentrated in nine types,such as train derailment(collision),fire,terrorist attack,earthquake,flood,mechanical(equipment)failure,power failure,signal failure and crowded stampede.(2)Disaster chain theory is used to analyze the disaster mechanism,evolution mode and derivative transmission characteristics of the subway disaster chain.The complex network theory is used to construct the chain transfer diagram of eight typical disasters and the multi disaster coupling complex network model.(3)Complex network theory and basic element method are used to determine the statistical index of disaster chain complex network model,analyze the topological structure of disaster chain network and derive the structural importance of the nodes in the network.Based on the complex network theory and the network anti-destructive evaluation,the importance of the network edge of the Metro disaster chain evolution network is analyzed.Analytic Hierarchy Process is used to comprehensively evaluate the nodes of the disaster chain network.The top 20 nodes in the subway disaster chain network are listed as the first level important nodes.The top 20 edges of network edge vulnerability are listed as the first level important edges.(4)Based on Bayesian network theory and disaster chain theory,the metro disaster risk assessment index system is determined.The metro disaster Bayesian network risk probability assessment model is constructed,the inference calculation of the two-way probability of nodes in the Bayesian network is realized by using Netica software,and quantifiable risk control measures are proposed through sensitivity analysis.(5)The terrorist attack on the St.Petersburg subway is an example to verify the disaster chain,assessment model.The results show that the accident disaster chain and disaster chain network model is highly consistent with the real accident evolution.This paper analyzes and determines the key control nodes and edges and puts forward the risk control measures,which provides a theoretical basis for the risk control of urban rail transit operation.