泥石流堆积泛滥区危险度的评价与应用

THE EVALUATION AND APPLICATION OF RISK DEGREE FOR DEBRIS FLOW INUNDATION ON ALLUVIAL FANS

泥石流堆积泛滥区危险度是指山地沟谷一旦发生泥石流后,在堆积区不同地段泛滥成灾的程度或最大威胁程度.本文探讨了泥石流堆积泛滥区危险度评价的指标体系,划分了四级危险度。应用泥石流二维非恒定流理论建立了危险度评价的数学模型。以云南东川市城区为实例,模拟了100年一遇超标准泥石流泛滥成灾过程,并作出泥石流堆积区的最大流速分布图、最大泥深分布图和危险范围内的危险度分区图.通过数值模拟取得了良好的效果。根据危险度评价结果,提出了该数学模型在减灾中的应用。

The risk degree of debris flow hazard on alluvial fans indicates the serious extent of debris flow jeopardizing or imperilling the construction and lives in dif- ferent section of alluvial fan,in case of happening hazardous debris flow.This paper approached the target system which is used to evaluate risk degree for de- bris flow inundation on alluvial fan,and divided it into four levels.A mathemati- cal model evaluating risk degree has been established,based on the two-dimen- sional unsteady flow equations.Authors make Dong Chuan City as an example to simulate the inundation process of debris flow which will occur one time in 100 year.The maximum velocity and depth distribution maps and risk degree zoning map of debris flow hazard on alluvial fan have been worked out,and reach a good result.According to the evaluation result of risk degree,non-engineering measures against debris flow hazard for urban construction have been put for- ward.