Research on stability of the accumulated rock-soil body of reservoir bank under rainfall condition  

作　　者：GU ChongShi1,2,WU HaiZhen1,2 & SU HuaiZhi1,2 1 College of Water Resources and Hydropower Engineering,Hohai University,Nanjing 210098,China 2 National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Hohai University,Nanjing 210098,China 3 Jiangxi Water Conservancy Research Institute,Nanchang 330029,China 

出　　处：《Science China(Technological Sciences)》2009年第9期2528-2535,共8页中国科学（技术科学英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 50539010, 50539110, 50809025, 50539030-1-3);National Science and Technology Support Plan of China (Grant Nos. 2006BAC14B03, 2008BAB29B06, 2008BAB29B03);Opening Fund of Geotechnical Mechanic and Engineering Key Laboratory of the Ministry of Water Recourses of China (Grant No. G07-03);Science and Technology Support Project of China Hydropower Engineering Consulting Group Co. (Grant No. CHC-KJ-2007-02);Special Scientific Research Fund of Doctor Subjects of Colleges and Universities: Research on Diagnosis Method of Concrete Dam Crack Transferring

摘　　要：The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir,that is,the relationship between cohesion and gravel content,between friction angle and gravel content,and the relationship between cohesion and water content,between friction angle and water content,is studied based on the direct shear test results,the shear strength change law of the rock-soil aggregates is given,and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper,through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation,but appears several hours after the rainfall cessation,this phenomenon is in accordance with the practical slope engineering's failure process and could explain appropriately the slope failure caused by rainfall infiltration. Research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir,and can enrich the stability analysis method and relevant theory of reservoir embankment slope.The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir, that is, the relationship between cohesion and gravel content, between friction angle and gravel content, and the relationship between cohesion and water content, between friction angle and water content, is studied based on the direct shear test results, the shear strength change law of the rock-soil aggregates is given, and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper, through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation, but appears several hours after the rainfall cessation, this phenomenon is in accordance with the practical slope engineering’s failure process and could explain appropriately the slope failure caused by rainfall infiltration. Research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir, and can enrich the stability analysis method and relevant theory of reservoir embankment slope.

关 键 词：RESERVOIR BANK slope rock-soil AGGREGATES rainfall INFILTRATION saturated/unsaturated SEEPAGE 

分 类 号：TV223[水利工程—水工结构工程]