Bi-Level Optimization Model and Algorithm of the Layout of Integrated Transport Hub in Urban Traffic Network

The realization of integrated transport hub's expected functions depends strongly on the location of stations on the traffic network and the matching relationship between the various stations based on the traffic network since the layout of integrated transport hub is planned on the existing urban traffic network. In this paper, a bi-level optimization model based on urban traffic network is established according to transport planning theory, for solving the problem concerning the quantity and location of integrated transport hub stations. Taking total social travel cost of the network as system optimization objective, the construction expense is considered as the constraint in the upper-level model, equilibrium assignment model is taken as lower-level model in which travelers' transfer time is considered as certain length of road section which is joined by the station, then the network flow is assigned for user optimal objective according to the given traffic OD. Then, the paper discusses the suitable algorithm. Finally, the study of the planning of Chengdu integrated transport hub is given as an example.