为分析非饱和土边坡的稳定性,研究了渗透系数与基质吸力的关系,考虑了饱和度对渗透系数的影响,建立了非饱和土不同强度下的土-水特征曲线(soil water characteristic curve,SWCC).利用Abaqus有限元模拟软件分别模拟了轴平移技术实测的SWCC和应用修正计算方法修正的SWCC,分析了坡内孔隙水压力变化、坡体变形和坡内塑性区出现的区域.研究表明,直接应用轴平移技术测试的SWCC进行边坡稳定性分析时,得到的坡内土体变形、等效塑性区较实际情况偏小,土的真实强度将被放大,存在安全隐患;应用SWCC修正计算方法,更接近边坡内土体的实际情况,并能降低工程隐患.
In order to analyze the stability of unsaturated soil slope,we investigate the influence of saturation on permeability coefficient. We establish the relationship between the soil water characteristic curve( SWCC) and the unsaturated soil strength under the consideration of the permeability coefficient and matric suction. Using Abaqus finite element simulation software,we compare the SWCC measured by axial translation technique and modified calculation method,and analyze pore water pressure,the slope position,slope deformation,and the plastic zone of the slope. The results show that the direct analysis of slope stability by SWCC with axial translation technique will give smaller slope deformation and smaller equivalent plastic zone than those of the real situation,and the real strength will be exaggerated. So there exists a security problem. The application of SWCC with correction calculation method can better grasp the real situation in the slope soil and reduce the engineering hidden trouble.