露井同期开采诱发边坡破坏机理的研究

Study on the mechanism of slope failure caused by simultaneous mining in open well

露井同期开采对边坡稳定性影响的问题是目前研讨的热点内容之一。以紫金山金铜矿开采活动为工程实际背景,对崩落法开采方案下露井同期开采作用下边坡破坏机理进行了模拟研究。结果表明:地下与露天合成叠加开采效应对边坡岩体稳定性影响非常大,其最大下沉值达到-7.68 m,因此必须采用高接顶率充填开采方案。露井同期开采影响下边坡岩体应力场受到两种采动同期作用,导致边坡岩体破坏更加剧烈,除要合理确定开采方案外还需考虑开采推进顺序的影响,从坡外侧向坡内推进更有利于边坡稳定性。此外由于地下和露天同期开采的复合叠加作用,地表的下沉出现多个小区域范围的下沉盆地,边坡岩体也可能产生多区域的滑动破坏体。

The issue of the influence of simultaneous mining in open wells on slope stability is one of the current hot research topics.Taking the mining practice of Zijinshan gold-copper mine as an engineering example,this paper simulates the failure mechanism of the slope under the simultaneous mining of open wells under the caving mining scheme.The results show that the combined mining effect of underground and open-pit has a great influence on the stability of the slope rock mass,and its maximum subsidence value reaches-7.68 m.Therefore,a filling mining scheme with high roofing rate must be adopted.The stress field of the slope rock mass under the influence of simultaneous mining in the open well is affected by the simultaneous action of two kinds of mining,resulting in more severe damage to the slope rock mass.In addition to reasonably determining the mining plan,it is also necessary to consider the impact of the mining advancement sequence.Pushing from the outside of the slope to the inside is more conducive to the stability of the slope.In addition,due to the combined superimposition of underground and open-pit mining,multiple small-area sinking basins appear in the surface subsidence,and the slope rock mass may also produce multi-regional sliding failure.