边坡的三维稳定性分析比其二维平面应变模型在理论上更能反映边坡的实际情况。为研究软弱夹层对边坡稳定性的影响,引入三维圆锥体平动破坏机构和牛角状螺旋圆锥体转动破坏机构,建立三维转动-平动组合破坏机构,并通过平面插入的方法实现破坏机构沿边坡的纵向拓展以便用于任意长度的边坡稳定性分析。结合算例分析,通过与弹塑性有限元数值模拟结果进行对比,验证了本文方法的有效性。分析表明,组合破坏机构能够很好的用于含软弱夹层边坡的稳定性分析并为实际工程提供一个简单有效的设计方法。
Three-dimensional analysis of slope stability is developing. Compared with two-dimensional method, this method can reflect the condition of slope more closely to the fact. Based on the upper bound limit analysis method, a new three-dimensional rotation-translation combined mechanism is proposed to study the stability of slope with weak interlayer. And this combined mechanism can be expended longitudinally through the plane insert;so the method could be used to analyze the slope stability with different lengths. The proposed failure mechanism is finally verified by comparisons with the elastoplastic finite element method. The comparisons show that the proposed mechanism improves the efficiency of the previously-developed rigid block mechanism to account for the presence of the weak interlayer in the slope and can be used as a simple evaluation method for the engineering design.