Assessing the Blockage Risk of Disaster-Relief Road for a Large-Scale Earthquake

Abstract

After a large-scale earthquake, the road is susceptible to get blocked by liquefaction or building collapse, and that results in disaster-relief difficulty. This study adopted two earthquake loss estimation systems in Taiwan, and the risk of road blockage caused by liquefaction or building collapse was calculated separately. A new modeling was proposed, and the comparisons of the results of a single factor and that of the joint factors were made. Four scenarios of peak ground acceleration (PGA) = 250, 400, 550, 750 Gal were tested. The result shows that the probability of road blockage due to liquefaction almost reaches the maximum when PGA hits 400 Gal. On the other hand, the probability of road blockage due to building collapse increases if PGA increases. The joint probability of road blockage due to liquefaction and building collapse can improve the underestimation when using either one factor, and it can evaluate the risk more realistically. At present, there is no risk assessment modeling considering two important factors for disaster-relief road planning in Taiwan. This study provides a simple and comprehensive disaster-relief road risk assessment modeling to make better emergency rescue plans. In addition, it can provide the information for conducting seismic strengthening policy for both sides of the disaster-relief road that can reduce the risk of obstacles to disaster-relief roads.