汶川地震扰动区小流域地质灾害风险概率问题  

Study on Geological Hazards of Small Watershed Risk Probability in Wenchuan Eathquake Disturbance Area

作　　者：薛志航[1] 邓创[2] 樊晓一[3] 乔建平[4] 王萌[4] 吴彩燕[3] 

机构地区：[1]国网四川省电力公司电力科学研究院,四川成都610072 [2]国网四川省电力公司电力应急中心,四川成都610000 [3]西南科技大学土木工程与建筑学院,四川绵阳621010 [4]中国科学院地表过程与山地灾害重点实验室,中国科学院成都山地灾害与环境研究所,四川成都610041

出　　处：《灾害学》2016年第3期39-45,共7页Journal of Catastrophology

基　　金：国家电网公司科技项目(521999150031);国家自然科学基金项目(41272297);科技部重点国际合作项目(2013DFA21720);国家青年科学基金(41301592);中国科学院山地灾害与地表过程重点实验室自主支持基金项目资助(2013年度);长江科学院开放研究基金资助项目(CKWV2015228/KY)

摘　　要：汶川地震扰动区地质灾害的特点是滑坡崩塌极为发育,泥石流物源丰富,灾害发生频率高。以都江堰白沙河小流域为例,在完成小流域风险区划的基础上,采用Logistic回归统计模型分别对震后小流域中滑坡泥石流发生的临界降雨量及时间概率,不同等级风险区（高、较高、中等、较低,共4级风险区）滑坡泥石流发生的临界雨量及空间概率进行分析统计。研究表明当日降雨量是触发滑坡泥石流的时间条件,发生概率为0.7~0.9。大暴雨是触发高、较高风险区滑坡泥石流的空间条件,发生概率可达到0.9。发生风险损失的临界雨量为大暴雨。The characteristics of geological hazards in Wenchuan earthquake disturbance area are numerous landslides and rock falls,rich debris flow materials,and high occurrence frequency of hazards. We selected Dujiangyan City as the study area. Based on small watershed risk zonation,logistic regression model was adopted to make a statistics analysis on critical rainfall and time probability aiming at landslides and debris flows of small watershed after earthquake and them in different grade risk zones. The study results showed that intraday rainfall was the time condition to trigger landslide and debris flow with probability of 0. 7 to 0. 9. Heavy rainfall was spatial contidion to trigger landslide and debris flow in higher and high risk areas with occurrence probability of 0. 9. Critical rainfall to make risk loss was heavy rainfall.

关 键 词：汶川地震 扰动区 小流域 地质灾害 临界雨量 风险概率 

分 类 号：X43[环境科学与工程—灾害防治] P642[天文地球—工程地质学]