|关键词: 降雨入渗 抗剪强度 压力水头 边坡稳定性
|Calculation method for soil slope stability under-the action of precipitation infiltration
XING Xiao-di1, ZHANG Lei2, TAN Ye-fei3, QIU Cheng-chun4, XIE Xing-hua3
1.Key Laboratory of Navigation Structure Construction Technology, Nanjing Hydraulic Research Institute, College of Water Conservancy and Hydropower, Hohai University;2.Yellow River Shandong Bureau;3.Key Laboratory of Navigation Structure Construction Technology, Nanjing Hydraulic Research Institute;4.Qinghai Yushu Electric Power Development Co., Ltd.
|Based on the model test data, presenting the soil shear strength parameters and precipitation infiltration time as a function of the moisture content, modifying the simplified Bishop calculation model make it being able to reflect the phenomenon that the strength of the soil mass would be reduced by the change in the moisture content of the slope soil mass. With the aid of Fortran program, a program which is coupling saturated-unsaturated seepage finite element method and limit equilibrium slope stability (a corrected simplified Bishop method) is developed in this study. The program takes into account the slope soil shear strength parameters changed along with the development of precipitation infiltration, using saturated-unsaturated seepage for calculating variation and expansion process of the moisture content of the slope soil mass during rainfall. Through physical model tests, slope seepage in the development process and the process of change in the slope safety degree under the rainfall conditions have been calculated and analyzed. And the calculated results are good in agreement with the experimental research results, which differs by about 35% from the slope safety factor given by the simplified Bishop method before correction. This corrected simplified calculation method for slope stability will provide a new useful reference for the calculation of precipitation induced landslides.
|Key words: precipitation infiltration shear strength pressure head slope stability