Construction Of Multi-layer Disaster Chain Network In Urban Rail Transit System And Its Security Situation Assessment

With the expansion of the scale of the city,the rail transit system becomes more and more complex.Therefore,when a disaster occurs in the system,secondary disasters or even derivative disasters will probability triggered.making the disaster process a chained structure.The disaster chain of urban rail transit system refers to the phenomenon that disasters occur one after another in the urban rail transit system.For the urban rail transit system,because the space where the system is located is relatively closed,the system structure is relatively complex,so there are often more than one disaster chain.Different disaster chains are intertwined and a disaster chain network is formed.Based on the related theories of disaster chain and multi-layer networks,this paper takes the disaster events of urban rail transit system as the research object,and builds a multi-layer network model of the urban rail system disaster chain.and quantifies the probability of initiation between disaster events.Then based on this model,the security status of the urban rail transit system was evaluated.This article specifically completed the following work:First,this paper proposes a method of quantitative description of the relationship between disaster events based on conditional probability.Based on this method,a single-layer disaster rail network of urban rail system was constructed.Furthermore,a multi-level disaster chain network of urban rail transit system was constructed based on the spatial division of the urban rail system.Then,a multi-index evaluation model for the security situation of disaster events was conducted,and the evaluation index system and its weights were determined using the analytic hierarchy process.Combining the propagation probability between the disaster chain network and the disaster,the fuzzy evaluation method was used to evaluate the change trend of the disaster chain network security status.In addition,this article uses a comprehensive evaluation method,combined with some indicators of network invulnerability,to rank each of the disaster propagation processes,that is.each side of the network.Finally,taking a given set of rail transit disaster statistics as an example,a multi-layer network modeling method proposed in this paper is used to establish a model.In the simulated disaster scenario,the security situation of the network was evaluated.It also showed how to use the results of the importance of the disaster chain network to provide management personnel with decision support in terms of safety and rescue.