Research On The Method Of Bus Transit Network Adjustment In The Initial Operation Of Urban Rail Transit

China is driving the urban rail transit construction rapidly. In the initial operation, the lines are usually laid on the main traffic corridor. With the competition and cooperation of metro and bus on the corridor, the bus lines should be adjusted and organized to strengthen the connection between two modes according to the transfer of passenger flow inside the system. This research has an important theoretical value and practical significance to promote the sustainable prior development of public transportation system with rail and bus transit network convergence.Some characteristics are analyzed aimed at the initial operation of metro:1) trip characteristics of transit passengers (trip mode and time),2) development features of public transportation system (passenger volume and passenger transport structure),3) passenger transfer characteristics on the corridor,4) passenger flow characteristics of metro (network\line load, coefficient of transfer and average distance carried at system level and at line level),5) bus lines change characteristics before and after the operation of metro (passenger flow volume and distribution), and 6) passenger flow transfer characteristics at the metro station (transfer mode, space and time range).The characteristics of city development, trips and function and layout of metro at the beginning of construction in our big cities are summarized. The strategies of transit network adjustment are proposed (shift of network function and layout, rail and bus transit transport network convergence and adjustment of bus lines).The way to dividing bus lines and hubs according to the different function are studied, and then the transit network layout form in the initial operation of metro are proposed. The junction form of rail and bus transit network are studied with analysis of the spatial, competition and cooperation relations between them.The width of rail transit corridor are analyzed from two perspectives-pedestrian catchment area and value-added effect of land. The set of bus lines which will be adjusted is built after filtering lines by exploratory factor analysis and cluster analysis considering geometry, supply and demand features. Bus lines selection criteria according to the function are studied, and then lines are classified. The bus lines are cross classified to several categories according to above two ways, and then the adjustment measures, plans and sequences for each category are put forward.The range of feeder bus service area is studied considering layout of rail transit, trip characteristics, administrative boundary, geological characteristics and location of bus terminal. The existing landuse and traffic facilities in the feeder bus service area are analyzed. The lines attached road network selection criteria are studied considering grade, network and conditions. The generation set of candidate stops is studied with the spatial relationship and cohesion among bus stops, terminals and metro. The heuristic rules and solving steps are built to obtain the candidate set of feeder bus lines by comparing kinds of path searching algorithm. A lines generating model for selecting lines from the candidate set is built, which aims to minimize the bus travel time and maximize the population and employment which stops cover. Then the improved genetic algorithm is designed for solving the model. Finally, the proposed method is applied to an example to verify effectiveness.