降雨条件下软岩边坡渗流-软化分析方法及其灾变机制  

Method of seepage-softening analysis and disaster mechanism in soft rock slope under rainfall

作　　者：谢瑾荣[1,2] 周翠英[2] 程晔[2] 

机构地区：[1]中交第四航务工程勘察设计院有限公司,广州510230 [2]中山大学工学院,广州510275

出　　处：《岩土力学》2014年第1期197-203,210,共8页Rock and Soil Mechanics

基　　金：国家自然科学基金资助(No.40672194);中央高校基本科研业务费专项资金资助(No.11lgpy04)

摘　　要：降雨条件下软岩边坡的灾变问题是滑坡领域研究的热点与难点。采用间接耦合法进行软岩边坡降雨入渗分析,根据软岩边坡非饱和渗流-应力计算原理,建立了软岩边坡渗流效应分析方法;将软岩抗剪强度的遇水软化特征动态赋予暂态饱和区中对应的软岩体,模拟降雨渗流条件下软岩边坡的软化效应;将渗流与软化相结合,建立基于暂态饱和区的软岩边坡降雨-渗流-软化-灾变的数值分析方法,并用于实例边坡的降雨灾变机制分析。结果显示,软岩边坡潜在滑动面深度随时间逐渐变浅,安全系数-时程曲线呈反向复曲线形态,当边坡开始软化时曲线上出现拐点。边坡稳定性计算结果与实际情况基本相符,表明思路与方法具有一定正确性,可为软岩边坡治理方案设计提供理论依据。Soft rock slope engineering catastrophic mechanism is a hot difficult subject in slope engineering. According to soft rock slopes unsaturated seepage-stress calculation principles, indirect coupling method is used to analyze soft rock slope stability under rainfall infiltration. A method for analyzing seepage effect has been established. The water-softening characteristics of the shear strength of soft rock are given to the corresponding soft rock in transient saturated zone dynamically, simulating the softening effect of soft rock slope in rainfall seepage. Then, combining seepage and softening, a numerical analysis method for soft rock slope rainfall-seepage-softening-cataclysm analysis has been established based on transient saturation region, which is used to research the disaster mechanism of the slope engineering. The results show that, the depth of the potential sliding surface shallow gradually over time; the shape of stability factor-time curve is reverse recovery curve; and the inflection point appears on the curve when the slope begins to soften. The slope stability calculation results are consistent with the actual situation, so as to show that the proposed thought and method have some validity and can provide a theoretical basis for soft rock slope management program design.

关 键 词：软岩边坡 降雨 暂态饱和区 渗流 软化 

分 类 号：TU452[建筑科学—岩土工程]