Scheduling work zones for highway maintenance projects: Considering a discrete time-cost relation

Highway maintenance usually requires lane closures and disrupts traffic operations. Transportation agencies face increasing pressure to reduce construction time and alleviate the traffic impact. However, accelerated construction and compressed schedules are expensive. This study focuses on improving traffic operations and the efficiency of maintenance work through optimizing work zone schedules. The objective total cost, including agency and road user costs, is minimized while a discrete relationship between maintenance time and the associated cost is considered in the mix. A genetic algorithm is developed to solve the combinatorial, multidimensional optimization problem. A numerical example demonstrates the applicability of the developed model and efficiency of the solution methodology. A sensitivity analysis explores the relationships among decision variables.