Research On Calculating Methods Of The Loading Capacity Of Urban Rail Transit Network

Urban rail transit is an effective mean of transportation to ease the traffic pressure. It is used in more and more large and medium-sized cities because of its large capacity, rapidity, punctuality, less pollution. Along with the large-scale construction of urban rail transit lines in china, urban rail transit lines changed from a single line into a network. In the context of urban rail transit network, the focus of urban rail transit carrying capacity will be converted from the line to network. The methods for calculating and evaluating the loading capacity of urban rail transit network are some new research domains, and of more challenges. Regarding urban rail transit network as a system, the researchers have done little things about the concepts and theories of network capacity because of its complexity. How to provide a reasonable method of calculating the loading capacity needs to do more research. This thesis on urban rail transit network loading capacity is necessary.First of all, the dissertation analyzes the basic relations between urban rail transit lines and studies five characteristic structures of urban rail transit, proposes the evaluation indicators of urban rail transit network structure. At last this thesis shows the topology description and constructs the mathematical model of the urban rail transit network.Secondly, the concept of urban rail transit network loading capacity is proposed after brief review and entirely summarization of urban rail transit carrying capacity, based on this analysis of urban rail transit network loading capacity characteristics and the concept of significance. This section focused analyzes the main features and the influencing factors of urban rail transit network loading capacity, proposes the evaluation indicators of urban rail transit network loading capacity. Finally, the concept and model of the reserve capacity are briefly introduced.Finally, the major factors influencing the path choice are proposed by comparing the differences of path choice behavior between traffic and urban rail transit. Considering crowded conditions, comfort and the queuing time whiling transferring to another rail, we get the more reasonable path cost function. The zonal reserve capacity is defined and adopted as an integrated performance index to urban rail transit network loading capacity. Mathematically, it is formulated as a bi-level model, and gives the algorithm of model. This thesis put forward the cumulating methods of urban rail transit network loading capacity and applies the models and methods above to Beijing urban rail transit network.