Systemwide Optimization of Safety Improvements for Resurfacing, Restoration, or Rehabilitation Projects

Highway agencies face a dilemma in determining the appropriate balance of resurfacing and safety improvements in their programs to maintain the structural integrity and ride quality of highway pavements. Highway agencies currently lack a tool that would allow them to determine which sites should be resurfaced without accompanying safety improvements and which sites should be resurfaced and improved in other ways that would enhance safety. A resource allocation process that maximizes the benefits from resurfacing and safety improvements within a specified improvement budget can provide such a tool. A resource allocation process that accomplishes this goal has been developed and implemented in a software tool known as the Resurfacing Safety Resource Allocation Program (RSRAP). RSRAP uses an optimization process based on integer programming to determine which improvement alternatives (or combinations of alternatives) would optimize the benefits for a specified set of improvement projects. RSRAP incorporates the best available estimates of the safety effectiveness of specific geometric and safety improvements. RSRAP also gives consideration to the potential effects of resurfacing on vehicle speeds and on safety. The goal of the optimization process is not to optimize safety at any particular site but to optimize systemwide safety for a given set of resurfacing projects while not exceeding a user-specified improvement budget.