基于强度折减法的土石混合体边坡长期稳定性研究  

NUMERICAL STUDY ON LONG-TERM STABILITY OF SOIL-ROCK MIXTURE SLOPE USING STRENGTH REDUCTION TECHNIQUE

作　　者：刘康琦 刘红岩[1,2] 祁小博 LIU Kangqi;LIU Hongyan;QI Xiaobo(College of Engineering&Technology,China University of Geosciences(Beijing),Beijing 100083,China;Key Laboratory of Deep Geodrilling Technology of Ministry of Natural Resources,Beijing 100083,China;China Institute for Geo-Environmental Monitoring,Beijing 100081,China)

机构地区：[1]中国地质大学(北京)工程技术学院,中国北京100083 [2]自然资源部深部地质钻探技术重点实验室,中国北京100083 [3]中国地质环境监测院,中国北京100081

出　　处：《工程地质学报》2020年第2期327-334,共8页Journal of Engineering Geology

基　　金：国家重点研发计划(资助号:2019YFC1509701);国家级地质灾害应急防治(资助号:2019);四川省自然资源科技计划(资助号:KJ-2018-23).

摘　　要：土石混合体边坡是自然界中常见的一种边坡类型,具有明显的不均匀性和不连续性。土体的蠕变是造成土石混合体边坡变形及失稳的主要原因之一,而目前关于土石混合体边坡稳定性的研究几乎均未考虑土体的蠕变性。首先运用数字图像处理技术对我国某水电站库区的一个土石混合体边坡进行建模,而后利用FLAC3D软件中的强度折减法对其进行稳定性分析,并着重研究了土体的蠕变特征及其蠕变参数对土石混合体边坡变形及稳定性的影响。计算结果表明,土体的蠕变特征会明显降低土石混合体边坡的安全系数,增大边坡变形,进而对边坡的稳定性造成不利影响;其中蠕变黏性系数对边坡的长期稳定性具有较大影响,黏性系数越大,则土石混合体边坡的安全系数越低。Soil-rock mixture slope is a common type of slope in nature,which has obvious heterogeneity and discontinuity.Rheological property of soil is one of the main causes leading to the soil-rock mixture slope deformation and instability.But almost all the existing analyses on the stability of soil-rock mixture slopes neglect the rheological properties of soil.Using digital image processing technology,a soil-rock mixture slope model in the reservoir area of one hydropower station in China is built.Then the strength reduction method in FLAC 3D code is adopted to analyze the slope stability.The analysis mainly focuses on the creep characteristics of soil and the effect of the creep parameters on the deformation and stability of the soil-rock mixture slope.The results show that the rheological property of soil can obviously reduce the factor of safety of the soil-rock mixture slope,increase the deformation of the slope,and adversely affect the stability of the slope.The creep viscosity coefficient has a great influence on the long-term stability of slope,and the greater the viscosity coefficient is,the lower the safety factor is.

关 键 词：数字图像处理 土石混合体边坡 蠕变 强度折减法 安全系数 

分 类 号：TU443[建筑科学—岩土工程]