Research On Traffic Capacity And Cascading Failure Of Bus Transport Network Based On Layered Model

Urban public traffic is an import component of traffic systems, with the fast promotion of the urbanization process and the increase of the population, the existing urban public transport infrastructures can’t satisfy with the increasing travel demand. These problems of traffic also affect the urban economic construction and the operating efficiency.This paper is based on the theory of the complex network to further study the urban bus system. We propose a method to construct the two-layer model of urban bus transport network. With the model we research on the cascading failures of layered urban bus transport network and enhancing its traffic capacity. We hope that through research the dynamic behavior on the layered urban bus transport network we can improve the network efficiency and operation capacity. Our main work and achievement as follows:1. This paper proposes a method to construct the model of layered urban bus transport network. The urban bus transport network can map into space P and space L. We take space P as logical network while space L as physical network, then we get a model of urban bus transport network composed of space P and space L. The model is an important prerequisite to further research cascading failure and traffic capacity.2. This paper proposes the strategy to enhance the traffic capacity of layered public transport network. In the model of layered public transport network, we remove a fraction of links in the logical layer to improve the traffic capacity of the whole network. Through the simulation of the public transport network of Beijing, Shanghai and Hangzhou, we find that link-removal strategy can change the topological structure of the logical layer and improve the traffic capacity. The result helps us improve the operation capacity of public transport networks in the future.3. To research the process of cascading failure of layered urban public transport network, we respectively apply node-removal strategy and link-removal strategy in the urban public transport network. Through the simulation of public transport networks of three Chinese cities: Beijing, Shanghai and Hangzhou, we find that with the increase of the capacity parameter, the avalanche size decrease after removal the node or the edge with the highest load. At the same time, we propose the strategies to defend the cascading failures and provide suggestions to ensure the normal operation of urban public transport networks.