河流洪水灾害风险评价及对策研究

发布时间：2019-02-18 07:42

【摘要】：我国洪水灾害频繁发生,带来巨大的生命财产损失,严重威胁经济社会的平稳发展。为减轻洪灾损失,降低洪灾风险,实现由控制洪水向洪水管理的转变,需要防洪工程措施和非工程措施综合运用。洪水灾害风险评价可以全面掌握区域洪灾状况,对于提高民众风险意识、规范土地合理利用、促进工程措施与非工程措施的科学制定等具有重要意义。本文以现有的洪灾风险评价理论为基础,以复州河下游段为研究对象,将洪水数值模拟方法与地理信息系统结合,从洪水灾害的危险性和易损性两方面探讨洪灾风险评价方法,对研究区域的洪灾危险性和易损性进行了评价,并制定了相应的风险管理对策。本文研究了洪水灾害系统理论,分析了洪灾系统中的致灾因子、孕灾环境和承灾体因素。对洪灾风险的三要素洪水危险性、承灾体暴露性、承灾体易损性进行研究,分析对比了风险评价的常用方法,选择数值模拟与地理信息系统结合的方法进行研究区的洪灾风险评价。应用数值模拟和历史洪水两种方法进行了洪灾危险性评价研究。洪水数值模拟以设计洪水资料和地形等数据为基础,建立四个频率(0.5%、1%、2%、5%)洪水的泛滥模拟模型,以模拟结果中的淹没水深为主要指标评价划分研究区洪水危险性,完成四个频率洪水的危险性评价。历史洪水法在进行历史洪水调查的基础上进行,利用2012年暴雨洪水洪痕数据,结合研究区DEM数据在ArcGIS中进行空间分析,得到典型洪水的淹没水深分布,以此进行了典型历史洪水的危险性评价。两种方法应用于研究区洪水危险性评价取得了较好效果。利用GIS进行了基于格网思想的洪灾易损性评价。通过解译卫星遥感图像和地形图确定研究区地物类型分布,结合淹没情况选择早地、水田、园地、住宅用地、渔业用地、工矿用地六类承灾体,通过实地调查并参考其他研究成果确定了各类承灾体在不同淹没水深的洪灾损失率,结合水深分布数据利用GIS完成易损性评价,得到不同频率洪水时易损性分布及不同易损性区域面积的变化规律。探讨了通过承灾体单位面积价值估算洪灾损失的方法,并以研究区旱地为例计算了不同频率洪水时的旱地的洪灾损失。最后,进行了洪灾风险管理对策的研究。在目前风险管理对策的基础上,结合风险评价得到的风险图,制定了洪灾紧急抢险方案；进行了点线结合型的洪灾避险分析,综合考虑淹没水深、到达时间、受灾村庄分布、道路等情况,应用GIS网络分析功能,制定了洪灾避险逃生路线,并计算各路线的撤离时间,为洪灾紧急避险提供科学的参考。
[Abstract]:Flood disaster frequently occurs in our country, which brings huge loss of life and property, and seriously threatens the steady development of economy and society. In order to reduce flood losses, reduce flood risk and realize the transition from flood control to flood management, flood control engineering measures and non-engineering measures should be used comprehensively. Flood hazard risk assessment can master the situation of regional flood disaster in an all-round way, which is of great significance for raising the public's risk awareness, standardizing the rational use of land, and promoting the scientific formulation of engineering and non-engineering measures. Based on the existing flood risk assessment theory and taking the lower reaches of Fuzhou River as the research object, this paper combines the flood numerical simulation method with GIS, and discusses the flood risk assessment method from the hazard and vulnerability of flood disaster. The risk and vulnerability of flood in the study area are evaluated, and the corresponding risk management countermeasures are made. In this paper, the theory of flood disaster system is studied, and the disaster-causing factors, disaster environment and disaster-bearing body factors in flood disaster system are analyzed. This paper studies the three elements of flood risk, such as flood risk, exposure of disaster bearing body, vulnerability of disaster bearing body, and analyzes and compares the common methods of risk assessment. The method of combining numerical simulation with GIS is selected to evaluate the flood risk in the study area. Two methods, numerical simulation and historical flood, are used to evaluate the flood risk. Flood numerical simulation is based on design flood data and topographic data, and flood simulation models with four frequencies (0.5% and 2%) are established. The flood risk of the study area is divided into four frequency flood risk assessment based on the flood depth in the simulation results. Based on the investigation of historical flood, the historical flood method is applied to the spatial analysis in ArcGIS with the flood trace data of 2012 rainstorm and DEM data, and the distribution of submergence depth of typical flood is obtained. Based on this, the risk assessment of typical historical flood is carried out. The two methods have been applied to the flood risk assessment in the study area. The vulnerability evaluation of flood disaster based on grid is carried out by using GIS. Through the interpretation of satellite remote sensing images and topographic maps to determine the distribution of the types of features in the study area, combined with the inundation situation to select early, paddy, garden, residential land, fishery land, industrial and mining land six types of disaster bearing bodies, Through field investigation and referring to other research results, the flood loss rate of various types of disaster bearing bodies at different submergence depths is determined, and the vulnerability evaluation is completed by using GIS combined with water depth distribution data. The distribution of vulnerability and the variation of the area of the region with different frequency of flood are obtained. The method of estimating flood loss by unit area value of disaster bearing body is discussed, and the flood loss of dryland with different frequency flood is calculated by taking dryland of study area as an example. Finally, the countermeasures of flood risk management are studied. On the basis of the current risk management countermeasures, combined with the risk map obtained from risk assessment, a flood emergency rescue plan was formulated. In this paper, the dot-line combined flood risk avoidance analysis is carried out. Considering comprehensively the flood depth, arrival time, distribution of affected villages, roads and so on, the GIS network analysis function is used to formulate the flood risk escape route and calculate the evacuation time of each route. To provide a scientific reference for flood emergency risk prevention.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV122

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