大奔流沟料场施工期高边坡稳定性数值模拟

Numerical simulation of high slope stability of in construction period at Dabenliugou quarry in construction period

锦屏一级水电站大奔流沟料场边坡开挖高度468 m,开挖量巨大,岩层陡倾坡外,快速开挖卸荷过程中边坡安全稳定问题突出。在边坡破坏模式分析的基础上,建立了考虑层状岩体各项异性的数值分析模型,研究边坡开挖过程中应力、位移、塑性区和锚固受力演化特征,并评价边坡稳定性。研究表明,边坡整体稳定性主要受控于边坡的地质结构特征、层间错动带和岩层层面的抗剪强度等因素。总体上,开挖完成后边坡安全系数满足规范要求。

The material field with height slope height 468 m at Dabenliugou quarry at gully in Jinping Hydropower Station is 468 m and characterized by huge excavation amount,and deep sdeep stratum inclined towards slope outsideinclination towards outside slope,thus the slope stability in fast unloading during quick excavatedion unloading process is rather serious.Based on analysis of slope destruction mode,the numerical model considering anisotropy of layered rock is established.The slope stress,displacement,plastic area and anchorage condition variation during the excavation process is studied,and the stability evaluation is conducted.The results show that the slope stability is decided by geological structure,interlayer fault belt and interlayer shear strength;generally,the slope anti-stability coefficient can meet the requirement of design requirements.