大冶铁矿深凹露天开采最终边坡稳定性分析

Stability analysis of a terminal slope in Daye deep open-pit mine of China

针对大冶铁矿东露天最终边坡的工程地质条件,结合实际的开挖步骤与顺序,采用极限平衡理论和有限差分数值模拟两种方法,从分析开挖卸荷引起的边坡岩体应力、位移和塑性区变化规律入手,对最终边坡的整体稳定性进行计算分析.结果表明,边坡安全系数大于1.25,基本处于稳定状态.三个计算剖面上,由开挖引起的应力、位移和塑性区的分布和变化规律基本一致.回填体不仅提高了边坡的稳定性,还为转入地下开采提供了所需的安全覆盖层厚度.

According to engineering-geological conditions and mining sequences, the limiting equilibrium theory and numerical simulation were used to study the stability of East Open-pit Slope in Daye Iron Mine, China. By analyzing the changes of the stress, displacement field and plastic zones, the stability of the slope was inspected. The results indicate that the safe factor is greater than 1.25, illustrating the slope in a stable state. On three sectional profiles, the distributions and changes of the stress, displacement and plastic zones induced by excavation are ap- proximate. The back filling at the slope bottom not only enhances slope stability, but also provides the safe overlay which is needed in underground mining.