A Bi-level Programming Pricing Model Based On Risk Sharing For Highway Projects Under The Conditions Of Public Private Partnership

In the PPP(Public Private Partnership)highway project,the concession price is a key factor affecting the benefit of government,private investors and highway users.Therefore,how to reasonably determine the concession price of PPP expressway has become an important problem in PPP negotiation.At the same time,the PPP project cycle will be affected by many risk factors.A reasonable risk-sharing program is critical to the success of a PPP project and can have a significant impact on the concession price.However,the existing researches rarely take risk factors into consideration in the concession price decision process.How to determine the concession price of PPP highway project with a reasonable risk sharing method is still to be further studied and discussed.In order to enrich the relevant theories,this thesis constructs the bi-level model of PPP highway on the basis of reasonable risk-sharing method,considering the government,private investors and travelers' profits and maximizing the social benefits.It provides guidance for the PPP highway project price decision.In this thesis,41 risk factors are selected.And through the two rounds of Delphi method,the importance of risk factors and rational risk sharing method are discussed.Then with the application of Pareto's law,this thesis determines 31 risk factors that influence PPP highway project and a Quantified Risk Division Plan.The results show that most of the risk factors in PPP projects in China need to be shared by both parties,and the proportion of risk taken by private investors are slightly higher than that of government.It can be argued that an effective transfer of risk to private investors is achieved by the party that control the risk mostly.Based on the Quantified Risk Division Plan,a bi-level programming model is established to determine the concession price of the PPP expressway.This thesis discusses and analyzes the feasibility of using the bi-level programming model to determine the concession price of the PPP expressway and the influence path of the risk factors to the concession price.Then it introduces the risk sharing results into the pricing model,and fully considers the influence of the risk on the concession price.Finally,this article takes Jin-Shi expressway project as an example to verify the validity of the proposed method.Discussion and analysis of the relationship between the traffic volume and the franchise price are provided.