Quantitative Study On Risk Loss Assessment Of PPP Project Based On Toll Highway

With the continuous popularization and application of domestic PPP model,China’s PPP model has gradually entered the stage of standardized development.The value-for-money evaluation system of PPP model in China has also changed from qualitative evaluation to qualitative and quantitative evaluation.As a national key construction project in the next decade,expressway PPP project has the characteristics of large investment scale,long payback period,so it is of great significance to carry out quantitative risk research related to it.However,in the existing value-for-money evaluation system of PPP mode in China,there are a lot of subjective factors in quantifying the total risk loss of PPP projects,so it is difficult to clearly define the project risk interval caused by the actual PPP project when referring to its operation.Risk allocation based on an abnormal estimated project risk loss quantitative evaluation will probably lead the social capital party to take risks excessively,thus causing a series of events such as renegotiation to make the project suffer losses again.Therefore,effective quantitative analysis of overall risk assessment plays a very important role in risk loss evaluation of PPP projects.This study takes the PPP project of toll highway as the research object,and a G highway project in Jiangxi as the research case.Based on the project risk quantification theory and the risk characteristics of the PPP project of toll highway,the overall risk loss of the PPP project of toll highway is quantitatively simulated by Monte Carlo simulation method.First of all,the preliminary list of project risk factors is identified on the basis of combing and summarizing the relevant literature at home and abroad,and the preliminary list of risk factors of this project is supplemented and revised by expert investigation,and the list of risk factors of PPP project of toll highway is constructed;Secondly,based on the relevant theoretical knowledge of project risk quantification,the functional relationship of risk loss model is constructed,and in order to make the project risk quantification function more reasonable,each risk loss is innovative divided into two categories: consistent risk parameter variable and inconsistent risk parameter variable according to whether the probability and size of its occurrence are the same,and the two types of risks that may exist in this project are classified and analyzed step by step with reference to the risk list of this project,and the sub-functions of each risk parameter variable are analyzed and determined according to the actual data;Finally,combining the probability density function of sub-risk parameter variables and the probability density function and probability density accumulation function of overall risk loss of a G highway PPP project in Jiangxi Province,Monte Carlo simulation experiment is carried out by MATLAB software,and the distribution interval of the probability and size of overall risk loss under the existing social return rate interval of the PPP project is obtained.Finally,it is found that the overall risk of the project can be controlled under this model,but at the same time there are extreme values with small probability of occurrence but large impact.Finally,based on the simulation results,some risk management suggestions are given,such as strengthening the comprehensive ability of the government and enterprises,strictly controlling the cost and benefit of the project company,and improving the operational ability of enterprises.