基于理想点法的武都区北山泥石流危险度评价

HAZARDOUSNESS EVALUATION OF DEBRIS FLOW IN BEISHAN MOUNTAIN OF WUDU DISTRICT BASED ON IDEAL POINT METHOD

武都区北山泥石流灾害发育,对城区安全构成严重威胁。本文选取泥石流规模及发生频率作为主要因子,沟谷流域面积、主沟长度、流域相对高差、流域切割密度、泥沙补给长度比作为次要因子,采用理想点法对武都区北山7条泥石流沟进行了危险度评价。评价结果表明:研究区泥石流沟属低度危险-中度危险,与单沟泥石流危险度评价方法的结论基本吻合,符合实际情况,验证了该方法具有合理性及可靠性,为泥石流危险度评价提供了一种新的思路,同时也为研究区泥石流灾害的防治提供了科学依据和参考。

The debris flow in Beishan mountain of Wudu district is quite developed,posing a serious threat to the security of the downtown.The debris flow scale and outbreak frequency are selected as main factors,watershed area,valley length,watershed relative height difference,valley incision density and the length ratio of sediment supplement are selected as secondary factors.The ideal point method is used to evaluate the hazardousness of seven debris flows in Beishan mountain of Wudu District The evaluation result shows that the hazardousness of debris flows in the study area are low to moderate hazard,which is basically consistent with the conclusion of the site-specific debris flow hazard assessment and actual situation.It proves the ideal point method is reasonable and reliable.This method not only supplies a new way of thinking for hazardousness evaluation of debris flows,but also provides a scientific basis and reference for prevention of debris flows disaster in the study area.