Analysis of demand for road-based transport facilities: bi-level programming approach

A bi-level programming model is presented for determining the number of parking spaces and road-capacity expansions that are required to satisfy road traffic and parking demand. The lower-level problem is an equilibrium trip-distribution/assignment problem, and the upper-level problem is to maximize the net user benefit (or consumer surplus) by considering travelers' route and destination choice behavior and by satisfying the network capacity and attraction-end parking supply constraints. The use of consumer surplus in the objective function reflects an economic tradition that public investment in transport facilities (parking spaces and road capacities) should be operated in a way that maximizes the facilities' social benefits. A sensitivity-analysis-based heuristic algorithm is developed to solve the proposed bi-level problem and is illustrated with numerical examples.