Capacity Design and Pareto Improvement of Highway Toll Plaza in a Competitive Transport System

As the traffic infrastructure for collecting vehicle tolls, the capacity of the toll plaza determines the service level of the entire highway. The capacity of a toll plaza is highly correlated with its operating costs, especially in peak periods. In this paper, it is assumed that in a competitive transportation system, the residential area and the workplace are connected by a highway with a toll plaza which forms a bottleneck, parallel to a mass transit line; commuters can choose to travel by car or by public transport. By establishing an equilibrium model and two mathematical programming models, the capacity designs of the toll plaza were studied during the traffic service period to achieve three objectives, namely, the toll plaza breaking even, profit maximization, and total social cost minimization of the transportation system. The travel modal splits were analyzed under travel equilibrium in three situations, respectively. In addition, a bi-objective optimization model was developed to optimize total profit and total social cost, and a Pareto optimization scheme was analyzed. Finally, the theoretical analyses were also verified by numerical examples.