施工技术 2013年3月上 78 CONSTRUCTIONTECHNOLOGY 第42卷第5期 DOI:10.7672//sgjs2013050078 降雨强度对边坡稳定性影响的数值模拟研究* 孙永帅",贾苍琴?
,王贵和²,胡瑞林",周武平2 (1.中国科学院地质与地球物理研究所工程地质力学重点实验室,北京100029; 2.中国地质大学(北京)工程技术学院,北京100083) [摘要】影响边坡稳定性的因素很多,利用数值模拟分析方法研究了降雨历时、降雨强度对边坡稳定性的影响。
模 拟结果表明,在相同坡角、相同降南时间时,降雨强度越大,安全系数下降越快,土中孔醇水压力变化越快,土体位 移变化越大,边坡稳定性降低越快;降雨强度大的边坡滑动要先于降雨强度小的边坡,降雨强度越大土体越先达到 稳定状态,降雨强度大的边坡的人渗深度总是大于降雨强度小的边坡的人渗深度,降雨强度大的边坡安全系数始 终低于降雨强度小的边坡的安全系数。
[关键词】降雨强度;边坡稳定性;安全系数;降雨持时;数值模拟 [中图分类号]TU432;U416.14 [文献标识码]A [文章编号]1002-8498(2013)05-0078-04 NumericalSimulationStudy onSlopeStabilityDuringRainfall Intensity Sun Yongshuai', Jia Cangqin²,Wang Guihe²,Hu Ruilin',Zhou Wuping² (1.KeyLaboratryfEngineringGemechanicsIstituefGeolgyandGeophysis, Chinese Academy of Science,Beijing 100029,China; 2.School of Engineering and Technology,China University of Geosciences(Bejing),Beijing 100083,China) AbstractInthispaper,therearewfactorsintensityfrainfalland durationfrainfallwhichaft the stability of slope were studied based on numerical simulation. The results show that under the same slope of the thickness, the same rainfall time, the greater rainfall intensity, the faster the safety factor decline, the greater change in soil pore water presure, the greater change of displacement of soil. Finally,the displacementofsoilwillnhance,the stabilityof slopewill decrease;The slopeofbigrainfall intensitylidesbefore the slopefmallainfallintensity,hegreater theranfallntensityis,thefaster h stable state of the slope gets.The infiltration depth of the slope of big rainfall intensity is always greater than the infiltration depthof the slope of small rainfall intensity,the safetyfactor of the slopeofbig rainfall intensity is always lower than the safety factor of the slope of small rainfall intensity. Key wordsrainfall intensity;slope stability;safety factor;rainfall duration;numerical simulation 本文以人工从现场工地取土所制作边坡为研 边坡土体内部的渗流变化情况。
所模拟边坡角度 究对象,建立降雨人渗引发边坡失稳的数值模拟模 为45°(见表1),如图1所示。
型,对降雨时间、降雨强度对边坡稳定性的影响进 表1试验坡度和对应的降雨强度 行定性分析,并结合SEEP/W和...