路基边坡雨水浸透变形模拟研究

为了减少由于雨水渗透引起的路基边坡局部变形和失稳现象,在概述模型实验现象的基础上,采用饱和及非饱和渗流分析方法以及弹塑性有限元分析方法,模拟路基边坡模型中水位的变化和滑动破坏发生前的初始变形,建立渐进式边坡失稳的预测方法,通过实验进行再现分析,以明确边坡初始变形机理。研究结果表明:1)在饱和及非饱和渗流模拟中,当渗流系数设置值比渗透实验结果大时,模型实验的再现性良好;2)在弹塑性有限元分析中,通过边坡水位升高导致变形系数(刚度)减小,进而能够分析出模型实验中边坡的初始变形。研究过程为分析降雨期间路基边坡稳定性提供了新方法,其结果可为工程施工过程中避免发生大规模崩塌现象采取适当措施提供依据,为施工标准的设计和制定提供重要参考。

Simulation research on rainwater infiltration deformation of roadbed slope

In order to reduce the local deformation and instability of subgrade slopes caused by rainwater infiltration,on the basis of an overview of the model experiment phenomena,the saturated and unsaturated seepage analysis and the elastoplastic finite element analysis were used to simulate the change of water level in the roadbed slope model and the initial deformation before sliding failure.Then the progressive slope instability prediction method was established.Finally,through the reconstruction analysis of the rules with experiments,the initial deformation mechanism of the slope was clarified.The results show that:1) in saturated and unsaturated seepage simulations,when the seepage coefficient is set larger than the result of the seepage test,the reproducibility of the model experiment is good;2) in the elastoplastic finite element analysis,the deformation coefficient (stiffness) can be reduced by increasing the water level of the slope,thereby the initial deformation of the slope in the model experiment can be analyzed.The study provides a new way for analyzing the stability of roadbed slopes during rainfall,and the results can provide a reference for taking appropriate construction measures to prevent the occurrence of large-scale collapse,which is also beneficial for formulating future construction standards.HQ]