Study On Flood Risk Assessment And Flood Evacuation In The Flood Control Protected Area

The flood disaster has been one of the most important natural disasters in the world. In recent years, the global climate change and the increase of human activity intensity led to a significant increase in the frequency of global flood disasters, and caused huge losses. In our country, although the construction of flood control system has been improved constantly, but it is still hard to avoid the flood disaster. So how to effectively prevent and control the flood disaster has been paid more and more attention.The establishment of flood control protected area is a very important engineering measures for flood control, the dike can not only protect the targets in the area, but also have a certain role in regulation and storage to protect area from greater flood damage. In recent years our country’s flood control and disaster reduction strategy has changed from the original flood control to flood management. Flood risk assessment is the important basis for flood management decisions,and has an important guiding role to improve the efficiency and effectiveness of the flood management by evaluating the region-wide flood risk. At first, this paper analyzes the status research on flood risk assessment of domestic and foreign, and then uses numerical simulation model to simulate flood evolution of different scenarios in the lower reaches of Hebei Luanhe River right bank flood control protected area as an engineering example. After that this paper evaluates the flood risk of protected area in different scenarios by setting up an index system to adapt to the characteristics of flood and engineering and using the multi-objective variable fuzzy set theory on the basis of existing research achievements and applications of flood risk assessment, according to the characteristics of flood disaster of flood control protected area. At last this paper makes flood evacuation scheme on the basis of the results of flood risk assessment and flood simulation. The main research are as follows:(1) The numerical simulation of flood evolution under different conditions. Based on the terrain data, dikes and design flood data, this paper establishes status and planning condition of six recurrence interval (3 years,5 years,10 years,20 years,50 years and 100 years) by Mike 21 FM model, and then rearranges the submerged depth, flood inundation duration and maximum flood velocity results of different scenarios.(2) The establishment of indexes system and evaluation of flood risk. This paper analyzes the existing index system, and then determines a few indexes which are the important impact of flood risk to bulid the index system from the perspective of risk and vulnerability. In order to solve the fuzzy, imprecise and uncertain problems of flood risk assessment, this paper applys the multi-objective variable fuzzy comprehensive evaluation method to evaluate the flood risk comprehensively. This paper evaluates the flood risk of 100-year design flood for Hebei Luanhe River right bank in planning conditions to introduce the evaluation process and analyse the rationality of the evaluation results.(3) The making of flood evacuation scheme. This paper makes 100-year design flood evacuation scheme for flood control protected area on the basis of flood risk assessment and flood simulation. First this paper determines dangerous areas and resettlement mode and selects hedge placement according to the results of flood simulation and flood risk evaluation. Secondly the author paints by hand, supplements and regulates the urban roads network according to the RS data, and then creats road network data set. Thirdly this paper calculates the road travel time again the road impedance function. Finally, the optimal evacuation route is selected by the shortest total transfer time. And then the flood evacuation scheme is made according it.At last, the author summarizes the research results and problems of the whole paper, and points out the direction of further efforts.