Research On Network Scale Of Urban Rail Transit

In the last 20 years, with the rapid development of China’s economy and the high speed of urbanization and mechanization, big city’s traffic became more crowded which leaded traffic accident increased and environmental problems seriously. The Urban Rail Transit has become an important way to solve urban traffic problems because of its high speed and large capacity. Planning and construction of Urban Rail Transit system is the key to building a sustainable transport system. However, Urban Rail Transit is a large scale, high cost and complex system engineering. So, how to determine the reasonable scale of Urban Rail Transit network is a very important issue.On the basis of summarizing the existing research results, this paper has analyzed the influence factors of network scale and obtained the multilevel hierarchical structure diagram of network scale influence factors. At the same time, it summarized the existing network scale calculation method. Three kinds of calculation method (traffic demand method, service level method, regression analysis method) are compared and analyzed. It regarded traffic demand method as the basic method of reasonable scale of this paper by analyzed the three’s advantages and disadvantages. To achieve a more accurate calculation of reasonable size of the line network, this paper improved the problem of traffic demand method by improving the accuracy of the parameters.Firstly, it established the traffic demand forecasting model which calculated the total travel and the proportion of travel by rail transit. Then it analyzed the traffic benefit, economic benefit and social benefit related to rail transit line. According to the three parties, a reasonable length model of rail transit line is constructed with the principle of comprehensive benefit maximization. The model could obtain relationship between the reasonable length of single line and the passenger flow intensity. Next, the rail transit line is divided into different types at different urban areas. According to the characteristic analysis of passenger flow intensity of different types of lines, it has established the optimal value model of the passenger flow intensity. Last, it calculated reasonable length of every lines by the results of their passenger flow intensity. Added up every line length could calculate the overall reasonable scale of the line network.