Research On Optimization Of Road Dynamic Toll Pricing And Pavement Maintenance Strategy Under PPP

With the rapid growth of society and economy,Chinese people’s living standards have been improved unprecedentedly.Under this background,the large population and the increasing travel demand has presented new requirements for the development of China’s road infrastructure.At the same time,the construction of road infrastructure features large capital investment,high difficulty in technical management and long recovery cycle of capital,which brings great pressure of capital and technology for public sectors.PPP（Public-Private Partnership）introduces the social capital participation,which provides a new solution for the sustainable development of China’s road infrastructure.This paper studies the dynamic toll pricing and pavement maintenance strategies optimization for PPP projects.Firstly,the paper summarizes the research status of toll pricing strategies and pavement maintenance strategies at China and abroad,explains PPP’s basic theory as well as its advantages and disadvantages.In addition,this paper gives a summary of the influencing factors of the toll pricing strategies,pavement maintenance strategies and users route choices in the road network.Secondly,a single-objective optimization framework of road toll pricing and pavement maintenance strategies is constructed with the objectives of private sector profits,public sectors pavement maintenance costs and road network operation efficiency.This has given full consideration to the dynamic deterioration of pavement performance and the stochastic route choices of travelers in the road network.After that,the paper proposes the project-based multi-objective optimization framework which considers the profit of private sector and the CO₂（carbon dioxide）emissions of the road system as the optimization objectives.The impacts of determined travel demand,dynamic deterioration of pavement performance,pavement maintenance activities and vehicle travel speed on CO₂emissions are fully considered.Finally,combined with the previous single-objective and multi-objective optimization frameworks of toll pricing and pavement maintenance strategies,a multi-objective optimization framework for environmentally sustainable dynamic toll pricing and pavement maintenance strategy based on travelers’stochastic road choices on road network is proposed to improve the shortcomings of the former two.Under this framework,the objectives are maximizing the positive economic benefits of the public sector and the private sector,which contains the pavement maintenance cost of the public sector minimization and the profit of the private sector maximization,as well as minimizing the negative externality of the road network,which contains the operation efficiency maximization of the road network and the total CO₂ emissions minimization of the road system.Besides,the influencing factors of the previous two optimization frameworks are fully considered in this framework.The effectiveness of the optimization frameworks proposed in this study have been verified through examples,and the optimal toll pricing and pavement maintenance strategies are dynamically derived by programming via MATLAB software.While satisfying the interests of all stakeholders,it ensures the service level of road network,improves the operation efficiency of road network,and realizes the environmentally sustainable development of road infrastructure.It has theoretical reference significance for the adoption of PPP and the management of policy makers in road infrastructure.