Research On Comprehensive Planning Of Regional Rail Transit Network Layout In Urban Agglomerations

It is an inevitable trend that the formation of urban agglomeration in China’s urbanization process is an inevitable trend, and the relationship between the development of urban agglomeration and the regional railway transit planning and coustruciton is closely. The functional orientation and reasonable conection among urban rail transit, intercity railway, passenger dedicated line and common railway should be determined to accurately grasp the rail transport system positioning. The regional rail transit system integrated planning according to urban agglomerations spatial structure and trip characteristics can promote the formation of regional high-speed integrated transport system and provide solid transportation guarantee for well development of urban agglomerations, which has positive practical significance.The method of regional rail transit network integrated planning was researched with the background of the development of urban agglomerations in China based on the existing rail transit network theory and method research achievements in this paper. A urban agglomerations regional rail transit network multidimensional planning theory and method frame was built, including five contents below:Firstly, the urban agglomerations regional rail transit system was identied in terms of systematic science and method. Then the connotation of urban agglomerations regional rail transit integrated planning was defined, and the role and significance of three dimentions in the process of network planning form point, line and area. At last the theory of urban agglomerations regional rail transit network multidimensional planning theory was proposed.Secondly, after review and summary of existing intercity travel demand analysis system, the author proposed the time spent on urban traffic has a great impact on traveler’s main mode choice. Based on this idea, the existing intercity travel demand analysis system was improved that the access traffic model in O point and D point was individually brought into intercity travel demand analysis system.Thirdly, the travel efficiency in the interior points should be considered when network planning at the point dimention. This travel efficiency can be calculated by the hub accessibility. This paper presented the meaning of urban external traffic hub accessibility based on the analysis and summary of the research results and the existing problems. The urban external traffic hub accessibility can be described by the travel time, cost and comfort, quantified by the corresponding costs of time, ticket and fatigue. According to the disadvantages of current hub accessibility calculation model, an improved calculation model system and method was built based on dimensionless method and disaggregate model. Combined with specific case, this model was analyzed and the correctness and feasibility of the measurement result was verified.Fourthly, the author proposed that the intercity railway planning conditions need to be carefully considered during network planning at the line dimention. Through comprehensive analysis and filters, the passenger flow density of intercity railway is a main indicator for intercity railway planning conditions. The intercity railway planning conditions calculation model was built by ticket theory with financial analysis. In addition, by using descriptive statistics, the statistical results showed that per capita GDP and population density could be used as the reference indexes for intercity rail planning condition.Fifthly, at the area dimention, the author proposed that the urban agglomerations regional rail transit network distribution should be considered with point dimention and line dimention. The main transportation corridor in urban agglomeration can be determined by intercity passenger OD with cluster analysis. On this basis, based on analysis of passenger intercity generalized travel cost function and intercity railway planning condition model, a Bi-level multi-objective programming model of intercity railway network layout initial network was established. This model’s upper-level objective maximizes reserve capacity of regional comprehensive transport network. Its lower-level objective contains both minimum users’generalized travel cost and maximum operation condition. This model can be solved by turning to be a single level single objective programming using linear weighted sum method and branch-and-bound method. At last, a numeric example demonstrates the model’s validity and feasibility.Sixthly, an evaluation index system adapted to regional rail transit network layout scheme selection in urban agglomerations is established and an appropriate and feasible quantitative method for each indicator is presented. Selection method of regional rail transit network layout scheme in urban agglomerations is introduced based on Set Pair Analysis principle and the evaluation index weights are determined by entropy method. At last, the selection process can be calculated with software made by QT program. The uncertainty in evaluation process can be effectively reduced by this scheme comparison method and simplify the traditional comparison method. The comparison result is reasonable and effective with a certain value.