Abstract
Dam-break flood simulation can evaluate the impact of a dam-break, and is significant in conducting risk analyses, creating emergency plans, and mitigating calamities. This study investigates the dam-break flood propagation in the downstream urban areas of the Minzhi Reservoir in Shenzhen, China, based on a two-dimension shallow-water model (SWM-2D). The SWM-2D solves two-dimensional shallow water equations for free surface flow using the finite-volume method. A refined grid with an unstructured mesh of triangular cells, constrained by building walls, is constructed to represent urban structures in this model. The flood hydrographs of dam-break and the flood propagation under different failure modes are calculated by adopting two breach mechanisms, namely instantaneous dam-break and gradual dam-break. The results indicate that the peak flow of the instantaneous dam-break is relatively large at the beginning of the dam-break. The gradual dam-break peak flow is relatively small when seepage failure deformation develops towards the upper part of the dam. The inundation information during the evolution of the dam-break flood, including the regularity of the flood propagation, distribution of maximum water depth, and variation of depth and velocity with time are also analysed.
Highlights
Dams and reservoirs are vital hydraulic structures used for flood storage and energy supply, and they play an increasingly important role in regional and national economic development
Minzhi Reservoir is situated in the Longhua New District in Shenzhen, China
Dam-break floods in urban areas can lead to different flow problems and it is difficult to resolve these problems using numerical methods, such as flows with highly unsteady, hydraulic jumps, and wetting and drying problems
Summary
Dams and reservoirs are vital hydraulic structures used for flood storage and energy supply, and they play an increasingly important role in regional and national economic development. A broken reservoir dam results in dam-break flood, leading to the rapid release of large volumes of water. It may have devastating consequences on human lives, property, and infrastructure (Penna et al, 2013; Azeez et al, 2019), especially in urban areas and in areas with a high population density and high property concentration. Compared to other types of dams, such as concrete and rubber dams, earth dams have simple structures, and their loose soil particles have a relatively high probability of breaching. There are two major types of dam-break mechanisms: gradual dam break and instantaneous dam break. Significant progress, with high stability and accuracy, has been made in research on the instantaneous
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
