Proactive Seismic Rehabilitation Decision-Making for Water Pipe Networks Using Simulated Annealing

Abstract

Past earthquakes have demonstrated that water pipes are susceptible to leaks and breaks during earthquakes. These leaks and breaks cause disruptions in water distribution and cause various direct and indirect losses. Such losses can be minimized by proactive seismic rehabilitation of water pipe networks. However, due to large infrastructure funding gaps, utilities lack budgets to perform seismic rehabilitation of their entire networks. Hence, it is of utmost importance to identify critical pipes in the water pipe network to make the best use of the limited rehabilitation budget available to the utilities. The objective is to maximize postearthquake serviceability of the water pipe network using limited rehabilitation budget of the utilities. A simulated annealing-based optimization approach was created and integrated with a network-level seismic vulnerability assessment model to identify critical pipes for the proactive seismic rehabilitation of the water pipe network. Critical pipes for proactive seismic rehabilitation were identified for two benchmark networks found in the literature. The approach was validated by comparing the results with a simple length-based rehabilitation approach (state of practice) and an approach proposed in the literature (state of the knowledge). The comparison suggested that the approach created in this study can identify a more economical rehabilitation policy compared with the existing methods.