基于可拓灰色模型的台风暴雨型泥石流易发性评价

Evaluation on susceptibility of typhoon-triggered debris flow based on extension grey model

2019年8月10日,受台风"利奇马"登陆影响,安徽宁国抽水蓄能电站汇水区域内6条台风暴雨型泥石流暴发,对工程建筑设施及居民生命财产造成了巨大损害。台风暴雨型泥石流的易发性研究目前尚处于起步阶段,在对研究区内地质环境调查的基础上,总结了台风暴雨型泥石流特征,将可拓理论与灰色关联度法相结合,采用定量的方式对区内泥石流进行易发性评价,并将评价结果与规范推荐的评分法和三要素法进行对比分析。研究结果表明:台风暴雨型泥石流具有超强短历时降雨启动、低频性、群发性的特征;在可拓灰色关联法的易发性评价结果中仅虹龙河为中等易发,其余沟谷均为轻度易发;对比发现,在小流域面积泥石流沟的评价结果中,3种方法一致性较高,当流域面积增大时,规范推荐的方法出现偏高和偏低,而可拓灰色关联法的易发性评价结果更加稳定可靠,与实际调查情况更吻合,进而为台风暴雨型泥石流的易发性研究提供了一种新的思路。

On August 10,2019,affected by the landing of typhoon"Lekima",six typhoon-triggered debris flows broke out in the catchment area of Ningguo Pumped Storage Power Station in Anhui Province,causing great damage to the engineering construction facilities and residents′lives and properties.At present,the research on the susceptibility of typhoon-triggered debris flow is still in its infancy.Based on the investigation of the geological environment in the research area,this paper summarized the characteristics of typhoon-triggered debris flow.Combining the extension theory with the grey correlation method,we evaluated the susceptibility of debris flow in this area,and the evaluated results were compared with the standard recommended scoring method and the three factors method.The results showed that the typhoon-triggered debris flow had the characteristics of super short duration rainfall initiation,low frequency and massive occurrence;in the evaluation results of the extension grey correlation method,only the Honglong river was moderately prone,and the other gullies were mildly prone.The comparison shows that the three methods give highly consistent evaluation results for debris flow gullies with small valley area,however when the valley area increases,the results of standard recommended method is high or low,the extension grey correlation method give more stable and reliable results,which is more consistent with the actual investigation situation,thus providing a new idea for the research on susceptibility of typhoon-triggered debris flows.