三峡库区降雨型滑坡预警雨量阈值研究  

Study on Early Warning Rainfall Threshold of Rainfall Induced Landslide in the Three Gorg⁃es Reservoir Area

作　　者：杨诗诗 叶润青 付小林 吴润泽 熊能 文天龙 YANG Shi-Shi;YE Run-Qing;FU Xiao-Lin;WU Run-Ze;XIONG Neng;WEN Tian-Long(Wuhan Center,China Geological Survey(Geosciences Innovation Center of Central South China),Wuhan 430205,Hubei,China;Institute of Geological Survey,China University of Geosciences(Wuhan),Wuhan 430074,Hubei,China)

机构地区：[1]中国地质调查局武汉地质调查中心(中南地质科技创新中心),湖北武汉430205 [2]中国地质大学(武汉)地质调查研究院,湖北武汉430074

出　　处：《华南地质》2023年第3期445-454,共10页South China Geology

基　　金：国家自然科学基金(41701563);三峡后续工作地质灾害防治项目(0001212020CC60002、0001212018CC600010、0001212012AC50021)。

摘　　要：三峡库区是滑坡灾害高发地区,降雨是诱发滑坡的主要因素之一。本文以三峡库区101例降雨型滑坡为研究对象,结合1980—2019年降雨监测数据,采用滑坡发生前10 d的日降雨量数据,拟合出三峡库区降雨强度-降雨历时(I-D)关系阈值曲线表达式,进一步拟合出不同规模、地层岩性、坡度、坡向、高程等因素下,不同发生概率的降雨型滑坡I-D阈值曲线表达式,并计算滑坡不同发生概率的临界降雨阈值。研究表明:滑坡易发地层区的降雨阈值相对小。三叠纪巴东组岩层发生滑坡的降雨阈值最小,其次为侏罗系;阳坡为滑坡的易发坡向,且阳坡滑坡的降雨阈值小于阴坡;滑坡规模和高程与降雨阈值呈正相关性;坡度小于25°时滑坡发生的概率最大,对应的降雨阈值最小。本文研究成果可为三峡库区降雨型滑坡预警预报提供支持。The Three Gorges Reservoir area is rich in high incidence of landslide disasters,and rainfall is one of the main factors inducing landslides.Taking 101 rainfall-type landslides in the Three Gorges Reservoir ar-ea as the research object,with reference of the rainfall monitoring data from 1980 to 2019 and the daily rain-fall data 10 days before the development of the landslide,this paper fits the threshold of the rainfall intensi-ty-rainfall duration(I-D)relationship in the Three Gorges Reservoir area,then further fits the I-D threshold curve expressions of rainfall-type landslides with different occurrence probabilities under different scales,stratum lithology,slope,slope aspect,elevation and other factors,and finally calculates the critical rainfall thresholds for different occurrence probability of landslides.The study shows that the rainfall threshold in landslide-prone stratum is relatively small.The rainfall threshold of landslide in Badong Group in Triassic is the lowest,followed by Jurassic;The sunny slope is prone to induce landslide,and the rainfall threshold of sunny slope landslide is less than that of shady slope;The scale and elevation of landslide are positively corre-lated with rainfall threshold;When the slope is less than 25°,the frequency of landslide is the largest and the corresponding rainfall threshold is the smallest.The research results of this paper can provide reference for the early warning and prediction of rainfall induced landslide in the Three Gorges Reservoir area.

关 键 词：降雨型滑坡 降雨I-D阈值曲线 临界降雨量 预警预报 三峡库区 

分 类 号：P642.22[天文地球—工程地质学]