Hengyang City Bus Network Optimization

Based on the current situation of the lower public transport development, the single type of public transport and the imperfect structure, this thesis selects more than 100 public stations and stops and over 20 traffic communities to make a lot of field surveys and obtains some data. Through the data, this thesis discusses the optimization of public transport network in Hengyang city according to the demand forecast-network analysis and proof optimization-whole optimal scheme-typical intersection optimization.Based on the gravity model, it uses the layering distribution method to amend the public transit, analyzes and brings forward the public traffic distribution in different districts in Hengyang and the OD predictive matrix on the distribution of the urban public transit trip. By the means of mathematical model, the three core objectives of public line network optimization, "the highest passenger's direct arriving rate, the shortest passenger's traveling time, the minimum cost of public transport running cost", can be transformed into three aggregation calculation ones that can be calculated aggregately, "the general shortest waiting time for vehicles, the whole shortest time for taking vehicles, the whole shortest time for vacancy", so as to realize the transform from multi-objective function to single-objective function and then simplify the calculation process of line total benefit proof optimization. Through example analysis, the lines have been optimized item by item; On the basis of the long-range objective of urban public transportation development and combining with real condition, it puts forward the detailed plan on the whole optimization of the traffic line network in 2010 and 2020 in Hengyang: that is through adding, deleting, adjusting, extending the lines and regulating vehicle numbers, service frequency, stopover station to realize the total goal of public transit "eight points, six lines, five circuits, seven districts", so as to practically improve the public transport construction, development and service level. Taken the intersection by Jinzhu Mall for typical example, it brings forward a scheme, which is to carry to on avoidance adjustment on public transit line in a short time and build viaducts in long run, to solve the problem of traffic jam at the intersections.The series of researches and conclusions not only can realize the whole optimization of the urban public transit network in Hengyang, but also can optimize the single line and the bottleneck intersections. This thesis should be able to provide valuable decision reference for the construction and development of public transport for the same kind cities.