公路岩质边坡稳定性评价的能量法研究

针对公路岩质边坡稳定性分析评价问题,根据能量法原理和塑性极限分析上限定理,建立了岩质边坡平面滑动的屈服机构.在刚塑性假定条件下,视岩质边坡的滑体为刚体,没有内能耗散,视滑面为塑性区,能量耗散主要集中在滑面上,根据能量法可以得到简化后的虚功率方程.综合考虑作用在岩质边坡上的后缘裂缝静水压力、沿滑面扬压力、重力、水平地震惯性力、锚固力等外力,按照强度折减法,推导得出了公路岩质边坡稳定性评价的能量法上限解.通过典型算例,将能量法上限解和刚体极限平衡法稳定系数计算结果进行了对比分析.

Study on Energy Method for Estimation of Highway Rock Slope Stability

Aimed at stability analysis and evaluation for highway rock slope, based on the theory of energy method and the upper bound theorem of plasticity limit analysis, a yield mechanism of planar failure surface for rock slope was established. On the assumption that the sliding mass of rock slope was treated as rigid body without internal energy dissipation while the sliding surface was treated as plastic zone where the energy dissipation mainly generates, the simplified virtual power equation in limit state was obtained by using energy method. With consideration of the hydrostatic pressure in back fissure, uplift pressure along slip surface, self-weight, horizontal seismic inertia force and anchorage force, the upper bound solution of energy method for highway rock slope stability analysis was deduced by means of strength reduction method. Through a typical case study, the computation results between the presented method and rigid body limit equilibrium method was compared.