诱发山地公路地质灾害的极端降雨事件辨识模型

以1998 ～ 2009年重庆市国省干线公路1 695个历史地质灾害点(含滑坡灾害点771个,崩塌灾害点924个)和分布区域内35个气象观测站的实测降雨数据为基本资料,分析了降雨与地质灾害的时空相关性、原始累积降雨量与地质灾害发生频数的相关性,结果显示两者关系密切,地质灾害的发生相对于降雨具有一定的时间滞后性,滑坡、崩塌地质灾害的发生受当日降雨量的影响,更大程度上受控于前期累积降雨量,滑坡、崩塌灾害分别与灾变前8天、前6天的降雨情况最相关；根据相关性分析结果,利用统计回归方法对诱发地质灾害的有效降雨量计算模型做了改进,认为有效降雨量计算的权重是天数和降雨强度的函数,推导了诱发山地公路地质灾害的极端降雨时间判别模型,并例证了该模型在常规地质灾害预警中的应用方法.

Identification Model of Extreme Rainfall Events Induced Mountain Road Geological Disasters

Based on the fundamental data of 1695 geological disaster spots of Chongqing trunk highways from 1998 to 2009(which including 771 landslides and 924 dilapidations places),and 35 meteorological stations data obtained by measurement of rainfall in distribution area, the space-time relativity of rainfall for geological disasters, and the relativity of original rainfall with the frequency of the geological disasters are analyzed. The results show that they are in close relations. Compared with rainfall, the occurrence of geological disasters has certain a time-lag effect. The occurrence of landslide rock fall of geological disasters are impact of precipitation, controlled by in a greater degree antecedent accumulated rainfall. Landslide rock fall is respectively or rainfall condition of precipitation 8 or 6 days before catastrophe. According to correlation analysis result, the effective rainfall calculation model of induced geological disaster has been improved by using statistical regression methods.It is suggested that effective rainfall calculation weight is function of days and rainfall intensity.The discriminant model of extreme rain time for inducing highway mountain geological disaster is derived. A illustration is given that the model’s application methods in conventional geological disaster warning.