动载下岩石边坡稳定性研究

采用拟动力法分析了岩石边坡在动载力作用下的极限承载力。采用Hoek-Brown强度准则描述岩体的抗剪特性,并得到等效的Mohr-Coulomb强度参数。基于离散法构建破坏模型,在此基础上,通过极限分析上限法推导并计算得到了极限承载力的上限解。分析表明,岩石本身强度参数对其稳定性影响比较明显;而水平动载加速度系数的影响明显大于竖直动载加速度系数的影响。初始时间差和岩体放大系数对极限承载力有显著影响。因此,在存在坡顶荷载的边坡稳定性设计中,应考虑因边坡地形等因素导致的动载作用放大的影响。

Analysis of Rock Slope Stability under Dynamic Loading

A pseudo-dynamic approach was adopted to analyze the ultimate bearing capacity of slope under dynamic loading. The Hoek-Brown yield criterion was used to describe the shear resistance of rock mass and the equivalent Mohr-Coulomb strength parameter was obtained. A failure mode was constructed based on the discretization technique and the upper-bound solution of ultimate bearing capacity of rock slope was derived based on upper-bound theory of limit analysis. It is shown that the strength parameter of rock has brought an obvious impact on its stability, and horizontal dynamic load acceleration coefficient obviously has brought more impact than vertical dynamic load acceleration coefficient. While the initial time difference and amplification factor of rock mass have brought remarkable impact on the ultimate bearing capacity of slope. It is concluded that the effect by amplification  of dynamic load action caused by slope topography shall be taken into consideration in the stability design for the slope with load on its crest.