降雨作用下和尚桥铁矿内排土场边坡稳定性分析

孔隙水压力是表征内排土场边坡渗流及稳定性演化的重要参数之一。为验证现有边坡设计参数的合理性,以和尚桥铁矿内排土场边坡为工程背景,基于Biot固结理论的直接耦合方法,运用Geo Studio软件进行数值模拟分析,研究内排土场边坡在降雨条件下的渗流规律及稳定性,分析降雨强度及降雨持时对边坡孔隙水压力的影响,得出不同降雨强度下边坡内孔隙水压力分布规律及其安全系数。结果表明：降雨入渗范围主要在排土场边坡表层以下3~5 m内;降雨入渗速率主要受到土体渗透系数与降雨强度相对大小影响;和尚桥内排土场边坡设计参数在持续强降雨期间仍能保持安全稳定,但需通过排水沟及时排出边坡表层未入渗的降雨。

Analysis on Slope Stability of Inner Dump in Heshangqiao Iron Mine under Rainfall

Pore water pressure is one of the important parameters to characterize the seepage and stability evolution of inner waste dump slope.In order to verify the rationality of the existing slope design parameters,taking the inner dump slope of Heshangqiao Iron Mine as the engineering background,based on the direct coupling method of Biot consolidation theory,numerical simulation analysis is carried out by using Geo Studio software to study the seepage law and stability of the inner dump slope under rainfall conditions,and explore the influence of rainfall intensity and duration on the pore water pressure of the slope.The distribution law and safety coefficience of pore water pressure in slope under different rainfall intensity are obtained.The results show that the rainfall infiltration range is mainly within 3~5 m below the surface of the slope of the waste dump.Rainfall infiltration rate is mainly affected by the relative size of soil permeability coefficient and rainfall intensity.The design parameters of the waste dump slope in Heshangqiao can remain safe and stable during continuous heavy rainfall,but the non infiltrated rainfall on the slope surface needs to be discharged in time through the drainage ditch.