Traffic Assignment And Road Pricing With Heterogeneous Values Of Time And Budgets On Toll

Both Values of Time(VoT)and Budgets on Toll(BoT)are important personal monetary characteristics primarily changed with the travelers’ income levels,the purpose of trips,which directly affect the route choice and network flow pattern in a tolled network.Many models that embrace the heterogeneity of VoT appeared in the literature,but fewer studies have been devoted to BoT.Considering the limitation of users’ travel cost on congestion toll,unsharability among different mental counts and different expectations of cost savings,BoT will contribute to traffic flow pattern significantly and should be heterogeneous.The impact caused by BoTs,along with VOTs,affects travelers’ different reactions to the same congestion toll scheme.Based on the above definitions and assumptions,this dissertation presents the issues,the traffic assignment and congestion toll with different VoTs and BoTs.The innovation of this dissertation is to integrate both VoT and BoT into one model,taking into account when BoTs are heterogeneous and when both are heterogeneous.Simpler models that embrace either of the attributes appeared a few times in the literature,but no study has been devoted to including both of them in an integrated model.This dissertation presents two mathematical programming models and methods to characterize and solve these problems.The main purpose of this dissertation is to provide models and algorithm methods for predicting the distribution of traffic demand in the tolled network and offering an optimal road pricing scheme.First,assuming that all travelers have the same VoT,we define user equilibrium criteria and propose a network equilibrium problem with heterogeneous BoTs in a tolled network.Then we present a mathematical programming model and method to characterize and solve this problem.Based on the well-known Frank-Wolfe algorithm framework,the core solution complexity lies in how to load travel demand into the network in an efficient manner.For tackling this difficulty,we developed a network loading procedure based on user equilibrium principle with heterogeneous BoTs.Based on this,we derive the optimal solution conditions of optimal traffic flow pattern to verify the existence of the first optimal road pricing scheme with heterogeneous BoT.It should be noted that the optimal system traffic flow for calculating the first optimal road pricing should be the traffic flow based on the heterogeneous BoTs.In this model,we assume that VoT is homogeneous.However,VoTs are different caused by personal income,travel purpose,preference for saving money,and so on,so VoTs should also be heterogeneous.This results in the second model,network equilibrium problem based on heterogeneous VoT and BoT.Until now,no research has considered both the heterogeneity of these two personal characteristics into one integrated model.Due to the convexity of the mathematical programming model,we can still use the Frank-Wolf algorithm to solve this problem,the biggest difference compared with the first model’s algorithm is the demand distribution during network loading process,we propose a three-stage network loading method to solve it.The numerical result derived from an illustrative example clearly shows how heterogeneous BoT and VoT reshape the network flow pattern characterized merely by user equilibrium.Then,an optimal timedifferent based road pricing scheme considering BoT and based on time difference is given.