Session6: Water-related Disaster Risk Reduction
Title: APPLICATION OF EMBANKMENT BREACHING MODEL TO SIMULATE DAMBREAK FLOODS OF BARRIER LAKES
Zhu Yonghui, Lv Qingbiao, Chen Dong, Zhou Jianyin
Barrier lakes pose great threats to the downstream due to their vulnerability to breaching. During the emergency disposal of the Tangjiashan Barrier Lake and the “10.10” Baige Barrier Lake in China, an embankment breaching model previously developed based on the mechanism of breach erosion as observed in various laboratory or field tests and prototype cases, was applied to simulate the dam-break floods. According to the continuous accumulated and updated measured or conjectured data transmitted from the sites which both are quite inaccessible, the model was applied to simulate a large number of possible scenarios of the dam-break floods for both barrier lakes, specially to predict the flood peak outflow and hydrograph, and help to evaluate the severity of the threat to the downstream area. The simulation results provide basis for the emergency evacuation of the population at risk. After the emergency disposal, back analysis of the draining process of the Tangjiashan Barrier Lake was also conducted by using the embankment breaching model to reproduce the well-monitored outflow hydrograph obtained during the draining process. This paper summarizes the simulation of the dam-break floods of the two barrier lakes and the back analysis of the draining process of the Tangjiashan Barrier Lake.