Research On Reasonable Scale Length For Urban Rail Transit Network

With the rapid growth of city population and gradual expansion of city land-use scale, the land usage begins to spread and the traveling demand of residents continues to increase. Under such circumstance, the unique feature of urban railway transportation, such as large capacity, environment protection, and convenience, elevate the service level of urban transportation and improve the traveling quality and efficiency of residents, which effectively reduce the quantity of private vehicles, and relieve the traffic congestion and pollution. Thus the railway transportation has great significance to sustainable development, especially in china, railway construction herald its prime development period.Although the construction of railways is restricted to social, political, economical condition, the network of urban railways which should be suitable for the city size and transportation morphology has always been the focus of domestic and abroad research.The suitable network scale for urban railways decides the balanced relations among regions, economies, population and traveling.This thesis introduces the technical economic features and types of urban railways at first; and then summarizes the main contents of network types and layout; finally, with the consideration of the coordinate development between railways and city, analyzes the influence of population and urban morphology on the urban railways network.According to the urban rail transit planning objectives and the analysis index, we consider the nets length as the important standard for the reasonable network analysis. Appling analytic hierarchy process, focused on the influential factors of urban rail transit network scale, we conclude a hierarchical structure which influences the network scale and analyze the relationship between the urban population scale and urban rail transit network scale. Then, applying neural network, we get the influential factors of urban rail transit network scale.According to three quantitative indicators:urban population in analytic hierarchy process, urban area and urban GDP, we put forward the following three methods for calculating the rational scale of urban rail transit network:1.Travel Demand Method based on urban population scale;2.Service Level Method based on urban area;3.Cost-benefit Method based on urban GDP。Then, combined with the neural network influence weight and all aspects, we find out reasonable scale of urban rail transit.Using the calculation model obtained by this paper, we give specific analysis of reasonable urban rail transit network scale of Neijiang. It provides valuable planning advice for builders of urban rail transit in Neijiang city.