边坡坡面浅层加固稳定性分析及设计参数探讨

基于有限差分的强度折减法,探讨坡面浅层土体加固边坡的稳定性,并针对地基与边坡土质相同和采用岩石地基2种工况,综合分析边坡加固区宽度和土体黏聚力、加固区进入地基土深度和边坡几何参数等因素对稳定性和滑动面的影响。结果表明:当地基与边坡土质相同时,不同加固宽度下边坡安全系数随加固区土体黏聚力增加均呈先减少后增加的趋势,且当土体黏聚力达到临界值时安全系数趋于稳定;随着加固区土体黏聚力的增大,边坡由浅层滑动变成深层滑动并最终完全不通过加固区,通过将加固区适当深入地基土可以提高边坡安全系数;当采用岩石地基时,随加固区土体黏聚力增加,安全系数总体上呈现先减少后近似线性增加,相同几何尺寸和土质条件下边坡安全系数比地基与边坡土质相同时整体上提高了0.5~1倍,加固区土体黏聚力越大即抗剪强度越高时,边坡安全系数越高。

Shallow Reinforcement on Slope Surface: Stability Analysis and Design Parameters

In this article,strength reduction method was employed to investigate the stability of slope reinforced in shallow surface.Moreover,the influences of reinforcement width,cohesion of reinforced soil,reinforcement depth (the depth of reinforcement area penetrating into foundation),and geometric parameters of slope on the stability and slip surface of slope were analyzed in the presence of soil foundation (the same material with slope soil) and rock foundation,respectively.Results showed that in the presence of soil foundation,the safety coefficient declined and then increased with the increasing of cohesion regardless of reinforcement width,and then remained stable once cohesion reached a critical value.With the increase of soil cohesion in the reinforced zone,the failure surface of slope moved from shallow surface to deep layer and then passed beyond the reinforced zone lastly.In this sense,increasing the depth of reinforced zone in the foundation could help enhance the stability.On the other hand,in the presence of rock foundation,the safety coefficient declined and then increased linearly in general with the increase of reinforced soil cohesion.With the same geometric parameters and soil material of slope,the safety coefficient was 0.5-1 times that of slope with soil foundation.As cohesion in reinforced zone increased,which means shear strength increased,the safety coefficient improved correspondingly.