多种因素作用下非饱和黄土边坡稳定性分析

Stability Analysis of Unsaturated Loess Slope Under Various Factors

通过拟静力法和Mogernstern-Price法结合计算地震工况下边坡的安全系数。考虑非饱和土基质吸力和渗透系数函数,运用SEEP/W模块计算降雨入渗时土体的孔隙水压力变化,并耦合SLOPE/W模块进行降雨工况和降雨地震耦合工况下的安全系数的计算。分析结果表明黄土边坡安全系数对水平地震荷载和坡度的变化更加敏感。降雨入渗条件下边坡的稳定性系数随降雨强度的增大先减小后缓慢增加。对归一化的曲线图进行分析可以发现,降雨量相同情况下水平地震荷载在0 g^0.3 g,坡度在15°~45°,拟静力法分析结果安全系数对坡度和地震的敏感性十分接近,且随坡度和水平地震荷载的变化趋势相同。

The safety coefficient of slope under seismic condition is calculated by the combination with pseudo-static method and Mogernstern-Price method. Considering the matric suction and permeability function of unsaturated soil,this paper calculate the variation of pore water pressure with soil infiltration by using Seep/w module,then the safety coefficient of slope under the coupling condition between rainfall and earthquake by the Slope/w module was calculated as well. The results indicate that the safety coefficient of loess slope is more sensitive to the variety of horizontal seismic load and slope angle. Under the condition of rainfall infiltration,the stability coefficient of slope increases first and then decreases slowly with the increase of rainfall intensity. By analyzing the normalized curve,it can be found that under the same rainfall condition,the horizontal seismic load is 0 g ~ 0. 3 g,and the slope is in the range of from 15 to 45 degrees,the analysis results of pseudo-static method show that the sensitivity of the safety coefficient to slope angle is very close to earthquake,and the variation tendency of the safety coefficient is the same as slope angle and the horizontal seismic load.