Linking users as private partners of utility tunnel public–private partnership projects

Linking users as private partners of utility tunnel public–private partnership (PPP) projects means treating users as internal core stakeholders in the designing, building, and operating phases, which is beneficial for precisely determining user needs, enhancing operational efficiency, and reducing user opposition. However, tunnel PPP projects are quasi-commercial projects, and users are not motivated to become linked. A reasonable incentive mechanism must thus be set up based on a systematic analysis of usersꞌ behaviors and incentive measures. Users of tunnel PPP projects were categorized as high- and low-cost users according to the difference in their traditional direct-buried costs. An evolutionary game model was established incrementally to investigate the incentive factors and their priority affecting the willingness and degree of users to be linked in tunnel PPP projects. The theoretical model was verified with a real Chinese tunnel PPP project, which suggested that the optimized scheme under the incentive mechanism is more efficient than the original solution. The research results indicate that the main factors influencing usersꞌ willingness and degree of being linked are the government subsidy rate, price discount rate, probability of enjoying a price discount, capital proportion, capital appreciation rate, and synergistic operational rate.