This work extends the network design problem (NDP) to the proposed road space allocation problem (RSAP), which finds the optimal lane configuration on each link in a road network that minimizes total system cost in a road network. To address efficiency and equity issues arising from road space allocation, this problem seeks the optimal alternative set, subject to an equity constraint, among various alternative sets that may include toll lanes, bus lanes, and roadway widening. In addition, an internal toll-funding scheme is incorporated here. This RSAP is formulated as a bi-level programming problem with an upper-level problem that optimally allocates road space and a lower-level problem that evaluates travelers' mode and route choices in response to each alternative. A multiclass, multimodal network equilibrium model is devised to efficiently evaluate road space allocation alternatives. To solve the combinatorial optimization problem, a heuristic algorithm based on simulated annealing is presented and applied to an example problem.
Abstract