栾川县暴雨泥石流预警模型研究——以“7.24”暴雨泥石流为例

Research on Early Warning Model of Luanchuan County's Rainstorm Debris Flow——Take“7.24”Rainstorm Debris Flow as an Example

以栾川县2010年7月24日暴雨泥石流为研究对象,对单沟泥石流进行预警研究。在参考前人研究成果及野外调查分析的基础上,结合栾川县降雨资料分析结果,选取前5d间接雨量、24h最大降雨量、1h最大降雨量、松散物质储量、山坡坡度、沟床比降、沟床弯曲系数、补给长度比和植被覆盖率9个指标,建立了基于地质背景条件与降雨因素相耦合的泥石流预警模型。采用三标度AHP法对相关因子进行赋权,采用功效系数法确定预警因子的单项功效系数,并加权求和确定总功效系数,根据总功效系数与泥石流预警等级的对应关系,对研究区单沟泥石流进行预警。预警结果基本符合"7.24"特大暴雨下的泥石流历史灾害发生规律,表明此预警模型是合理的,适用于对栾川地区泥石流预警。

Luanchuan County＆#39;s“7.24”rainstorm debris flow is taken as the research object to study on early warning of single gully debris flow .In reference to the previous research results and the analysis of field investigation , and combining the rainfall data＆#39;s a-nalysis results of Luanchuan , such as indirect rainfall before 5d, 24h maximum rainfall, 1h maximum rainfall, loose material re-serves, hill slop, gully bed ratio of slops, gully bed bending coefficient, supply length, and vegetation cover are selected, to estab-lish an early warning model of single gully debris flow based on the geological background conditions coupled with rainfall factors .By using three-scale AHP method to empower the relevant factors , determining the single efficacy coefficient of early warning factor with efficacy coefficient method , and weighting sum to determine the total efficiency coefficient , the single gully debris flow around the study area are early warned based on the corresponding relationship between total efficiency coefficient and debris flow warning level.The warning results are basically consistent with the regularity of the historical disasters of “7.24”rainstorm debris flow, which shows that the early warning model is reasonable , and suitable for warning the debris flow around Luanchuan area .