考虑格栅水力特性的柔性支护处治膨胀土边坡的数值模拟分析

Numerical Simulation Analysis of Expansive Soil Slope with Flexible Support in Consideration of Hydraulic Properties of Geogrid

运用Plaxis软件进行流固耦合分析,探讨了格栅水力特性对膨胀土边坡稳定性的影响,并在此基础上分析了不同降雨条件下柔性支护处治膨胀土边坡的原理。结果表明,随着雨水持续入渗,加筋边坡各层土工格栅轴力不断增加,呈中间大、两端小的“凸”型分布,忽略格栅的水力特性会低估格栅所受轴力、高估边坡稳定性。柔性支护结构可有效提高边坡抵抗降雨入渗的能力,维持膨胀土体抗剪强度,同时也能限制边坡变形和位移增长,是一种处治膨胀土边坡的有效方式。

The influence of hydraulic properties of geogrid on the stability of expansive soil slope was explored by conducting fluid-solid coupling analysis with Plaxis software.On this basis,the principle of flexible support for expansive soil slope under different rainfall conditions was analyzed.It is found that the axial forces on geogrid in each layer of the reinforced slope increase with the continuous infiltration of rainwater,presenting a“convex”shape variation.Without taking consideration of the hydraulic properties of geogrid,the axial forces on the geogrid will be underestimated and the stability of the slope will be overestimated.Flexible support structure can effectively control rainfall infiltration into slope and maintain the shear strength of expansive soil,meanwhile control the slope deformation and displacement growth.Thus,it is regarded as an effective way to support expansive soil slope.