Dam-Break Flood Routing Simulation and Scale Effect Analysis Based on Virtual Geographic Environment

Because of the barrier lake affected by highly changing and complex environment, it is always a great challenge that proper actions must be performed within a limited amount of time. Thus, how to scientifically and efficiently analyze the dam-break risk of the barrier lake and its impact area is very important for barrier lake disposal and downstream communities transfer. To improve the efficiency and the accuracy of the dam-break flood routing simulation, this paper mainly focuses on the construction of the virtual geographic environment (VGE) system and the scale effect analysis. Unlike most of the current cellular automata (CA)-based flood simulation systems, the proposed VGE system can offer an intuitive, efficient, and interactive visualization environment through which users can explore complicated spatial information and conduct risk assessment work. Some key technologies including the CA model of dam-break flood, the VGE system framework, the impact analysis method, and the scale effect analysis method were discussed in detail. A prototype system was developed to support dam-break simulation and risk analysis of the Xiaojiaoqiao barrier lake in Anxian County, Sichuan Province of China. By means of a variety of cell scales effect analysis experiments, the adaptation scope and characteristics of multiscale cells were obtained to implement the simulation analysis of the dam-break flood routing better. The proposed VGE system can improve the efficiency of risk assessment and decision-making.