Technologies for dam-break risk mapping based on DTM

Dam-break flood risk mapping is necessary to formulate flood prevention emergency plans and make analysis of dam-break risk.BREACH is used to stimulate changes in the shape of the break and calculate break-induced flow discharge.Two-dimension dam-break flood propagating numerical simulation is conducted based on unstructured grids and FVM.TIN model is applied to visualize the numerical simulation results.Risk maps of flood depth and flood velocity at different moments of dam-break,risk map of flood submergence duration,risk map of flood arriving time are drawn and used to carry out spatial analysis.The fundamental principles of drawing dam-break flood risk mapping are discussed in this paper.The methods proposed are applied to analyze Shaheji reservoir dam,which is of high value in practice.