Research On The Theory And Calculating Methods Of Railway Network Carrying Capacity

The railway is one of important nation infrastructures, main arteries of national economy and popular transportation tools. The Chinese railway is undergoing rapid developments. But there is a big gap between the supply of the railway carrying capacity and the social demand. Constructing a developed complete railway network and promptly expanding the carrying capacity of railway network are main tasks of railway span development.The whole railway network is made up of the railway stations and lines, and the carrying capacity of the stations and lines is the foundation of the carrying capacity of railway network. But the latter has far more meanings. The methods for calculating and evaluating the carrying capacity of railway network are some new research domains, and of more challenges. Regarding railway network as a system, the researchers have done little things about the concepts and theories of network capacity because of its complexity. There are great needs to do more research. If the railway administrations know clearly about the carrying capacity of the whole network, they can make out more reasonable schemes of the flow route, and also the authorities can choose more correct decision-making of constructing railway network. The dissertation is trying to integrate transportation demand into the situation of Chinese railway network, and the details are shown as follows.(1) The relative integrated concept system of the carrying capacity of railway network is put forward. After brief review and entirely summarization of railway carrying capacity, from the system theories of transport demands the new series conceptions are proposed, such as total carrying capacity, effective-use carrying capacity and potential carrying capacity of railway network.(2) Based on K-shortest path, the new series of conceptions on the key point of effective-use carrying capacity of railway network are proposed, such as minimum K-limit effective-use carrying capacity, maximum K-limit effective-use carrying capacity, economy effective-use carrying capacity and practical effective-use carrying capacity. The harmony validity of network facilities is brought into the notional category, and the dissertation gives the relationships between those new series of conceptions.(3) The concept and calculating methods for carrying capacity reliability of railway network are proposed. As for railway network, the connection reliability and travel time reliability are tightly contacted with railway network carrying capacity. Based on the reliability of flow route carrying capacity, the connection reliability related to carrying capacity reliability is analyzed and measured, and the travel time reliability related to railway network carrying capacity is discussed. The definition and calculating formula of railway network carrying capacity reliability is given on the base of uncertain scenarios.(4) Based on potential carrying capacity of railway network , the concept and calculating methods for carrying capacity flexibility of railway network are proposed when the railway network topology is changed. As a result, its value would be evidence of the railway network programming.(5 )The flow optimal mathematical models are proposed and the GA solution on the K-shortest path is given. Especially the paper describes a class of special stochastic chance-constrained programming models. In the case the chance constraints can be converted into their respective deterministic equivalents, then the equivalent deterministic models could be obtained, and an instance is presented. The experiments demonstrate that the certain and uncertain optimal models are feasible and would be promising ways.(6) The northern-east railway network in 2004 is developed as real practical instances. The values of carrying capacity of railway network and its reliability and flexibility are obtained when passenger transport channels will be constructed.