An Activity-based Bottleneck Model And Congestion Toll Pricing Issues

With the development of social economics,private cars increase rapidly while road volume couldn't accommodate such a heavy traffic.In the morning peak,congestion frequently happens at corridors connecting commercial district and residential neighborhood.Traffic congestion has become a world problem and need to be resolved.Transportation management either builds the mass road system or restrains demand of private cars.However,the expansion of roads is not only a waste of time,manpower as well as resources,and the increase of road capacity also stimulates the growth of car demand.The strategies of restraint on car demand include a limit to car,increase of car costs,congestion tolling and so on.The congestion tolling apply the economic price level to limit traffic demand leading financial revenues.Thus the revenues not only can be used to complement public transit and improve the quality of transport but can also afford costs of tolling.This paper extends the Vickrey's bottleneck model to address the departure time choice problem in the morning peak by introducing an activity-based bottleneck model.This model explicitly considers commuter's trade-off between the utility received by activities at home and at work and the disutility of travel between activity locations.The optimal time-varying toll and step toll are then investigated by using the activity-based bottleneck models with constant and linear marginal activity utility functions.The optimal toll solutions are also compared with the traditional Vickrey's bottleneck model.The results show that the curve of the optimal solution for the time-varying toll is not piecewise linear but piecewise quadratic when the marginal activity utility is linear.The traditional Vickrey's bottleneck model overestimates the queuing delay at the bottleneck,the step toll level and the start time and end time of the morning peak period.The optimal step tolls under the trip-based bottleneck model and the bottleneck model with constant marginal activity utility are half of the maximum value of the optimal time-varying tolls and exactly eliminate half of the total queuing delay at the bottleneck.The trip-based bottleneck model and the bottleneck model with constant marginal activity utility underestimate the role of step tolls in removing the bottleneck queues compared to the bottleneck model with the linear marginal activity utility.