Simulation of Dam Collapse Caused by Earthquakes

Abstract

The occurrence of earthquakes on the Korean Peninsula has been increasing in recent years. However, current emergency action plans for dam and reservoir failures only consider scenarios related to flooding but ignore dam collapses caused by earthquakes. In this study, we simulated dam collapses caused by earthquakes. We focused on the Chungju Dam watershed located in the upper reaches of the Namhan River and analyzed the dam collapse and downstream impacts using the DAMBRK model. We compared the downstream impacts of dam collapse caused by earthquakes with those caused by the PMF. When the dam collapsed because of an earthquake, the estimated peak flood discharge downstream was 44.9%-86.7% of that of the PMF scenario. Similarly, the simulated peak water level downstream when the dam collapsed due to an earthquake was 64.4%-96.9% of that of the PMF scenario. These results indicate that dam collapses caused by seismic events, even in the absence of rainfall, can lead to significant damage downstream. Therefore, future emergency action plans for dams should consider the potential for dam failures caused by earthquakes.