降雨入渗下残积土坡的失稳机理与加固治理  

Instability Mechanisms and Reinforcing Treatment of Granite Residual Soil Slope Under Rainfall Infiltration Condition

作　　者：柯云斌[1] 

机构地区：[1]台州学院建筑工程学院,浙江台州318000

出　　处：《水土保持通报》2010年第5期12-15,共4页Bulletin of Soil and Water Conservation

基　　金：福建省自然科学基金"饱和路基土的吸力行为及重载交通荷载下的力学行为研究"(2009J05121);福建省教育厅科技项目"重载下路面与软土地基动力共同作用及路面破坏机制研究"(JA08016)

摘　　要：针对典型非饱和花岗岩残积土边坡,基于饱和—非饱和渗流理论,分析了降雨入渗条件对残积土边坡渗流场与稳定性的影响,以及相应的加固治理方案。研究结果表明,边坡近坡表处的最大孔隙水压力和体积含水率均随降雨历时和降雨强度的增大而增大,从坡顶往下呈现大—小—大的变化趋势,且影响深度均随之增大;边坡稳定性在降雨初期下降比较显著,随着降雨历时增大,边坡稳定性下降趋势变缓并逐渐趋于一稳定值;当降雨历时较短时,降雨强度仅改变了近坡表附近的孔隙水压力分布及含水量,降雨强度对于边坡浅层溜方的影响不容忽视。鉴于基质吸力对边坡稳定影响很大,建议在工程设计中应考虑基质吸力对边坡稳定性的影响。Seepage field and stability on typical slope covered by unsaturated granite residual soil under rainfall infiltration condition are analyzed based on saturated-unsaturated seepage theory.Results show that maximum pore water pressure and volumetric moisture content in surface soil on slope increase with increased rainfall intensity and duration and present an increased large-small-large trend down slope.Slope stability significantly declines in initial rainfall stage and the downward trend changes slowly to a stable value with increased rainfall duration.When rainfall duration is short,rainfall intensity only changes pore water pressure distribution and water content in surface soil on slope.So the effect of rainfall intensity on shallow slope slipping can not be ignored.Because matrix suction can greatly influence slope stability,impact of suction on slope stability in engineering design should be considered.

关 键 词：降雨 残积土坡 饱和—非饱和渗流 加固 

分 类 号：P642.22[天文地球—工程地质学]