1.Southwest Geotechnical&Design Institute of China Nuclear Industry,Chengdu,Sichuan 610061,China;2.East China Jiaotong University,Nanchang,Jiangxi 3300 1 3,China;3.Wuhan Surveying—geotechnical Research Institute of China Metallurgical Construction Group,Wuhan,Hubei 430080,China;4.Beijing Guodian Water Conservancy& Electric Power Engineering Co.,Ltd,Beijing 100024,China
Abstract:Research purposes:Taking the K290 landslide of Yingtan—Xiamen Railway as all example,with the finite element method for saturated—unsaturated seepage,the variations of transient seepage field of saturated—unsaturated slope were simulated under the condition of change of rainfall and underground water level,the discussion is made on the variable laws of pore water pressure and matrix suction in the landslide under the conditions of different rainfall infihration.the analyses are made for the influence of rainfall intensity and rainfall duration on the stability of slope of the unsaturated slope,arid the evaluation is made on the results of prevention and treatment of landslide in the fields of micros and matrix suction.
Research conclusions: The changes of rainfall infiltration and groundwater level change make the rapid change of porewater pressure with the different change laws in different areas.At the initial stage of rainfall,there is a most notable variation of pore water pressure.Matrix suction of landslide changes with the change of rainfall.On later stage of rainfall,the most matrix suction vanishes,which is very harmful to the stability of slope.The water level change,rainfall intensity and rainfall have much influences on the stability of landslide,among them the comprehensive influences of rainfall intensity and water level change are the most prominent.In the circumstances of strong rainfall and underground water level going up and down,the stability coefficient of slope is reduced sharply.
[5] H. Rahardjo, X. W. L,i D. G. Tol,l E. C. Leong. The Effect of antecedent rainfall on slope stability [J]. Geotech- nical and Geological Engineering, 2001, 19(3) 371 -399.
[6] BoltonM D,Take W A,Wong P C P and Yeung F J. 2003. Mechanisms of failure in fill slopes after intense rainfal.l Keynote Paper, In.t Con.f on Slope Engineering, Hong Kong, China. Vo.l 1: 1 -25.