Research On Bus Type And Quantity Determination Of Flex-route Transit System

With the further development of urbanization process in China,a mass of population pours into the city.On the one hand,this situation expands the scope of the city,and the suburbs gradually away from the urban center.On the other hand,the connection between the suburbs and urban center are strengthening which stimulates the commute demand between the two places.The characteristics of scattered locations and long travel distance of suburban residents are not suitable for fixed route transit mode,which will increase the dependence of suburban residents on private cars and lead to a further worsening of traffic problem in urban city.Flex-route transit system(FTS)integrates the advantages of fixed route transit and demand responsive transit.FTS can provide door-to-door services while maintaining low operating cost,provide a new method to solve the travel problem of suburban residents.There are few researches on the bus carrying capacity of FTS in China.Studying the carrying capacity of FTS has great theoretical significance.This paper studies the methods of determining the bus type and fleet size of FTS to reduce the operation cost and improve the FTS management theory.The main elements of content in this paper are arranged as follows:After introducing the service characteristics of FTS,this paper summarizes the function orientation by comparing the operation characteristics of FTS,taxi and FRT,so as to clarify the applicable scope of FTS.This paper makes an in-depth analysis on the demand characteristics of FRT from three aspects: the impact of demand factors,travel characteristics of service groups and the temporal and spatial characteristics of demand.Demand forecasting is discussed after the analysis.The setting of the slack time and the determination of the operation cycle time are deduced by the formula.Based on this,the model for determining bus type and fleet size of FTS is established.Furthermore,this paper discusses the method to determine the mixed bus type of FTS in the case of large fluctuation of demand.The simulation experiment is designed according to the actual passenger flow data.The feasibility of the model is verified by comparing the advantages and disadvantages of the FRT mixed bus scheme and fixed route transit operation scheme.