基于模糊层次分析的彭州市牛圈沟泥石流危险度评价

RISK ASSESSMENT OF DEBRIS FLOW IN NIUJUANGOU IN PENGZHOU CITY BASED ON FUZZY ANALYTIC HIERARCHY

牛圈沟是一条多期次泥石流沟,沟口堆积扇显示,该沟历史上曾发生多次大规模泥石流,汶川地震以来也多次发生小规模的泥石流,对拟建彭汶高速公路的建设带来潜在危害。本文为在现场地质调研的基础上,结合无人机影像、遥感影像确定泥石流沟的基本特征,采用模糊层次分析法构建泥石流危险度评价模型,选取地形地貌、物源、触发条件为主要因子并针对性地选出10个次要因子对泥石流进行危险度评价。结果表明,牛圈沟、小牛圈沟、回龙沟、燕子洞沟、横河沟的评价等级为高度危险,连山沟、飞水岩沟、马场沟、石梁子沟、满板沟的评价等级为轻度危险,评价结果与泥石流实际调查结果具有良好的一致性。成果可为彭州市龙门山镇牛圈沟泥石流防灾减灾工作及彭汶高速公路工程建设提供科学依据。

Niujuangou is a multi-stage debris flow gully. The accumulation fan at the gully mouth shows that there have been many large-scale debris flows in the history of the gully, and small-scale debris flows have also occurred many times since the Wenchuan earthquake, which has brought potential threat to the construction of the proposed Pengwen Expressway. Based on the on-site geological investigation, combined with UAV images and remote sensing images to determine the basic characteristics of debris flow gully, the fuzzy analytic hierarchy process is used to construct the risk assessment model of debris flow. The topography, provenance and triggering conditions are selected as the main factors and 10 secondary factors are selected to evaluate the risk of debris flow. The results showed that the evaluation grades of Niujuangou, Xiaoniujuangou, Huilonggou, Yanzidonggou and Henghegou were high hazard, while the evaluation grades of Lianshangou, Feishuiyangou, Machanggou, Shiliangzigou and Manbangou were mildly dangerous. The evaluation results were in good agreement with the actual investigation results of debris flow. The results can provide a scientific basis for disaster prevention and mitigation of Niujuangou debris flow in Longmenshan Town, Pengzhou City and the construction of Pengwen Expressway project.