Budget Approximation for Optimal Highway Network Retrofit Problems

Abstract

Thailand has confronted with a lot of devastating floods. Some roads were heavily destroyed while others were partially damaged and emergency relieves could not access to the flooded areas. The Thailand Department of Highways (DOH) attempts to develop a budget approximation model for the highway network protection before an occurrence of the next flood disaster. The model will provide an approximated budget required to retrofit roadways before the occurrence of disaster that guarantees network connectivity and minimal associated costs. The proposed model is formulated as a stochastic bi-level program where the upper-level problem is a preemptive goal program and the lower-level problem is the user equilibrium condition. A heuristic solution method is provided for practical size problems. A sample network is examined to investigate the solution characteristics. It is found that the proposed algorithm can provide good practical solutions to the budget approximation for the highway network protection problem.