Study On Urban Rail Transit System Carrying Capacity Based On Network

As the main way to solve urban public transport problems, urban rail transit becomes the key point of urban public transport facilities construction and management. 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 system carrying capacity will be converted from the line to network. Previous research on the carrying capacity, however always take simple line as the background. The theory and cumulating methods of urban rail transit network carrying capacity have not yet been established. Therefore, this article on urban rail transit network carrying capacity is forward-looking and has a theoretical value.The whole urban rail transit network is made up of the stations and lines, and the study on the stations and lines carrying capacity is the foundation of the study on urban rail transit network carrying capacity. However, the network carrying capacity is not the simple sum of stations and lines carrying capacity, the relationship between the stations and lines has impact on the network carrying capacity. This paper, combining the operational characters of urban rail transit network and the theory of systems engineering, analyzes urban rail transit network carrying capacity.First of all, this paper analyzes the basic relations between urban rail transit lines and studies five characteristic structures of urban rail transit, which lays the way of the research in the network carrying capacity.Secondly, the theory and cumulating methods of station carrying capacity as well as the line carrying capacity are discussed respectively, which is considered as the foundation of the study on network carrying capacity. When discussing the station carrying capacity, this paper focus on the cumulating methods of transfer station carrying capacity; when discussing the rail transit lines carrying capacity, considering the impact of train irregularity, this paper introduces the concept of the "buffer time" into the train intervals and modifies the traffic capacity of urban rail lines. After that, this paper studies the traffic capacity of urban rail transit system by the way of probability theory on the condition that different sort of trains run on the same part of a line. Thirdly, combining rail transit lines carrying capacity factor and distance factor, this paper put forward the relative integrated concept system of the carrying capacity of urban rail transit network and analyzes the main features and the influencing factors of urban rail transit network carrying capacity. On this basis, considering the impact of transfer passenger flow, this paper put forward the cumulating methods of urban rail transit network carrying capacity and applies the models and methods above to Beijing urban rail transit network, and the result proves that the theory in this paper are useful to a certain extent.Finally, this paper presents the principal means and measures of "strengthening urban rail transit system carrying capacity and analyzes the coordination relations between the carrying capacity of stations and lines.