基于FLAC3D的膨胀土边坡渐进变形失稳机理研究

以安徽省北沿江高速公路（马鞍山至巢湖段）的膨胀性黏土边坡为对象,通过分析边坡变形失稳特点探究了此类边坡变形失稳机理,并基于FLAC3D软件针对某典型边坡开展了边坡稳定性的数值模拟分析。分析结果表明：该类膨胀土边坡失稳受水作用影响显著,膨胀性黏土遇水膨胀,且强度参数折减程度较大,膨胀土路堑边坡浸水后的破坏主要是发生在坡面浅层,且浸水程度愈深,边坡稳定系数愈低,这表明膨胀土路堑边坡的稳定性受浸水湿化效应的控制,通过在坡脚设置支挡工程防护,使得坡体的水平位移发生了显著的减小,加强了坡体的整体稳定性。

Research on expansive clay slope progressive deformation mechanism of instability based on FLAC3D

Choosing expansive clay slope which along the north side of Yangtze river highway in Anhui Province as an object,through analyzing the characteristics of slope deformation and instability to explore the mechanism of in- stability for such slope,we carried out numerical simulation analysis of slope stability for a typical slope based on FLAC3D software. The analysis results show that： Firstly,the instability for this type of expansive clay slope is af- fected by the action of water insignificantly,the expansion of swelling clay is according to the influence of water, and the degree for reduction of strength parameters is large. Secondly,the destruction of expansive soil cutting slope after flooding occurred mainly in shallow slope,and slope stability factor is lower when the level of its immersion in water is deeper. This indicates that the slope stability of expansive soil cutting was controlled by effects of flooding. Lastly,by setting retaining engineering protection at the foot of the slope,the horizontal displacement of slope is re- duced remarkably,and the overall stability of the slope is has been strengthened.