Research On The Durability Of Urban Composite Transportation Network Based On Coupled Networks

With the rapid development of urban public transportation network systems,large and medium-sized cities have established urban composite transportation networks with subway networks as the backbone and public transportation networks as the main body.This network has strong complexity and composite nature,exhibiting typical coupled network characteristics.The urban composite transportation network is the most important public transportation tool for people’s travel,effectively improving their travel efficiency and alleviating traffic congestion.At the same time,urban composite transportation networks are prone to sudden situations such as equipment failures and natural disasters,resulting in interruptions to transportation lines and even network paralysis,seriously affecting people’s travel.Therefore,this article adopts the coupling network theory to establish a model of urban composite transportation network,conduct research on network resilience,and provide technical support for ensuring the reliable operation of urban composite transportation network.The specific research content is as follows:Firstly,the characteristics of the urban composite transportation network were analyzed,and the Space L method was used to construct the subway network and the public transportation network respectively.The coupled network theory was used to establish the urban composite transportation network model,abstract the Chengdu composite transportation network,and analyze the complexity characteristics and survivability of the network.Secondly,key station identification methods for urban composite transportation networks were studied.To improve the identification accuracy of key stations,a composite transportation network key station identification method based on importance evaluation matrix is designed and proposed.Based on the importance evaluation matrix,passenger flow,network efficiency,and average factors are considered within the layer,and coupling strength factors are introduced between layers.An improved importance evaluation matrix is provided to identify key stations.The simulation results show that this method improves the identification accuracy of key stations by introducing factors such as coupling strength.Finally,a cascading failure model for urban composite transportation networks was studied.In response to the lack of description of the impact of coupling relationships on cascading failures in existing classical models,the occurrence process of cascading failures in coupling networks was analyzed,the load capacity model was improved,and a cascading failure model for urban composite transportation networks was established.Using station importance to define initial load and station capacity,the station is divided into three states:normal,overloaded,and failed.In the latter two states,a load redistribution method based on coupling strength is proposed.The simulation results show that this model can more effectively describe the cascading failure process of urban composite transportation networks.Under the overload and failure states of stations,increasing the coupling strength between stations can improve the anti cascading failure ability of the composite transportation network.