Evaluation Model And Method For Flood Submergence Of Dam And Levee Failure Based On Dem

Flood disaster has become a global issue of great concern, especially in floods caused by dam and levee failure, which is more destructive than the storm flood or the snowmelt flood. So many scholars have used various methods to analyze it. This dissertation analyzes the flood disaster based on previous studies, combined with DEM and GIS technology to find a method to fast calculate the flood volume caused after the dam break and use the calculated flood volume to forecast the inundated area and inundated depth in the downstream. So we can provide the basic data for relief flood disaster and flood assessment.This dissertation analyzes and researches the flood disaster mainly from the following aspects:Firstly, the structure and the access method of geospatial data were studied based on the geospatial data. At the same time, it also pretreats and cuts the DEM data.Secondly, two ways of existing inundated flood were analyzed: the calculation of inundated area given water level, and the calculation of inundated area given the flow. The calculation of the inundated area and the inundated depth after the dam break was separately made for the two inundated manners using of the function of ArcGIS itself and its secondary development. Two models in the calculation of these two inundated manners were considered: source inundated model and non-source inundated model. Combining with characteristics of flood to make the connectivity analysis in the calculation of the inundated area, and comparing the differences with flood inundated areas when it is connected or not connected under the same water level.Thirdly, the scope of the study was further expanded in this dissertation. It brings the upstream flood volume from the dam into the assessment model, which can make a more fitting practical calculation of the scope and depth of flood inundation led by the failure of dam and levee. First calculating the size of the upstream flood volume, and then including the calculated flood volume in the flood models, to analysis the scope and depth of flood. According to this idea to propose a method of volume inversion approximation, and realized it in the second development which is carried out by ArcGIS programming.Lastly, this research use the JingJiang flood diversion area as the experiment area and assuming that it has failure of dam and levee in the upstream and flood flows to the region. Through calculation and simulation result of flood inundation area and depth, it gets good results.