Scale & Layout For Suburban Railway Transit Network

The rapid increase of urban population,the rapid increase of urbanization,the continuous expansion of urban radiation,the continuous formation of metropolitan area,the re-reconstruction of urban spatial structure,these make that the urban traffic jam is getting worse day by day,the number of trips for residents is increasing,the travel distance is increasing,and the diversification of travel modes and so on.And a trip may need to be completed in various ways.In order to meet the growing transportation needs of urban residents who are becoming increasingly regionalized and adapt to the continuous development of urban public transport system in terms of convenience,diversity and integration,it will become the inevitable choice to build the suburban railways to solve many problems of urban transport development.Our country has just started its development in the suburban railways,coupled with its lack of scale and scale,its mode of development has not yet been clearly defined,its development concept and institutional mechanisms are still not perfect,and relevant research is still in its preliminary stage.Therefore,in order to prevent the blindness of the planning and construction of the transit network and to seek a rational and economical scale and layout of the transit network so as to create an efficient integrated urban public transportation system,the scale and layout of the railway in the urban area should be controlled macroscopically in line with the urban development level It is one of the important problems which need to be solved urgently in the early stage of network planning.The thesis starts from the above problems.It expounds the applicability and function of the suburban railway in urban areas,and analyzes in detail the four levels of the demand layer,service layer,route selection design layer and system layer of the main technical indicators of the suburban railway.By clarifying the functional positioning and applicability requirements of the suburban railways,it is possible to accurately grasp the connections and differences between suburban railways and other rail transit,and provide a powerful theoretical support for the research on the scale and layout of follow-up.On this basis,based on the analysis of the advantages and disadvantages of the commonly used calculation method,the paper proposed the demand analysis of passenger demand for spillover traffic following the principle of "supply and demand balance".Based on the perspective of integrated traffic,this paper uses the conversion coefficient method and gravity model method to calculate the overflow traffic and the inducing traffic demand,and builds the ideas and methods of calculating the size of the suburban railway network.In addition,the essay also analyzes the inherent relationship between the urban spatial structure and the network layout structure.In view of the advantages and disadvantages of the commonly used methods of rail transit network layout,a method of rail transit network layout based on node importance method joint traffic corridors is proposed.The paper determines the layout scheme of the suburban railway network in the city area through the importance of nodes,the degree of economic connection and the distribution of traffic corridors.Finally,taking the Chengdu Railway as the research object,and based on the model and method of the thesis,the line network has a reasonable long-term scale of 580 km.Then,based on the actual situation of urban passenger flow and the development of urban structure,this paper puts forward the proposal of short-term and long-term proposals on the scale and layout of suburban railway network in Chengdu,and makes a comprehensive analysis of the final scheme and verifies the rationality and feasibility of the method and model.The research results can provide strong theoretical support for the planning and construction of the suburban railway.