井工开采对露井联采边坡稳定影响的塑性极限分析

Plastic limit analysis of stability of the open-pit slope subject to underground mining

针对目前对露井联采边坡稳定研究方法的局限性和不足,首先根据露井联采边坡稳定的特征,基于塑性力学上限定理的边坡稳定极限分析方法,建立了井工长壁开采沉陷岩体的机动位移场,对沉陷岩体利用塑性极限分析方法建立功能方程。其次,利用该方法对安太堡南侧排土场下井工开采导致地表沉陷岩体进行了研究,分析了井工开采产生的沉陷对周围岩体特别是边坡岩体沉陷稳定和边坡稳定的影响,提出了露井联采边界参数应以井工开采工作面与边坡台阶的垂直安全距离为依据确定,其井工矿工作面开切眼位置应以Y=74160(与露天矿边坡水平距离为231 m)为界布置,才能保证其安全高度在105 m以上,实现安太堡南帮在露井联采下的安全稳定。

Aiming at the current limitations of the method for slope stability under open-underground mining,first of all,according to the characteristics of slope stability under open-underground mining and the limit analysis method for slope stability based on the upper bound theorem of plastic mechanics,a mobile displacement field of submerged rock under longwall mining is established,and in the meantime,the equation for submerged rock is obtained accordingly by using the method of plastic limit analysis.Secondly,the submerged rock of southern Antaibao open-pit slope under open-underground mining is studied by using the method,and the influence of subsidence caused by underground mining on vicinal rock and slope stability are analyzed.The following measures are proposed： the boundary parameter should be established depending on the vertical height of safe mining between mining face and slope bench.Accordingly,the mining face should be bounded by 71460（Y value） to ensure its vertical height of safe mining to be more than 105 meter,which can guarantee the stability of southern Antaibao open-pit slope under open-underground mining.