基于结构离散的复杂水平采空区群残采激励动力响应

Dynamic response of complicated horizontal goaf group under residual mining excitation based on structural discrete

为研究残采激励下复杂组合水平采空区群的动力响应,借助离散化方法,构建复杂水平采空区群动力响应模型。结合数值模拟,对某大型地下金矿山KT8矿体1100 m中段复杂水平采空区群进行动力响应及应力传递研究。结果表明:爆破激励下,水平采空区群结构的改变几乎不会对其作用岩体本身的位移响应和速度响应产生影响,但对其余部分岩体响应产生较为明显的增幅,其中增幅最大的区域是水平采空区群的结构改变处岩体;爆破荷载对其作用岩体应力分布产生较明显的变化,对其余部分岩体不会产生明显的影响。现场工程结果表明,复杂水平采空区群间柱经残采后,所形成新的大采空区稳定性良好,空区周边没有发生大的位移变形,并验证动力响应模型分析的可靠性,该方法为复杂采空区群残采作业提供理论指导。

In order to investigate the dynamic response of horizontal goaf group in complicated combination under residual mining excitation, a dynamic response modal of horizontal goaf group in complicated combination was established based on structural discrete. Dynamic response and stress transfer of horizontal goaf group in complicated combination on Level 1100 m of KT8 ore body in a large underground gold mine were researched combined with numerical simulation. The results indicate that the structure change of horizontal goaf group can not influence the displacement and velocity response of rock mass that blasting excites, while it would obviously increase the response of residual rock mass, among which the area of maximum increment belongs to structure change sector. Blasting load obviously impacts on stress distribution of rock mass it effects on while others not. Field engineering results show that goaf newly formed is in stable state and has no large displacement and deformation in the surrounding area after residual mining of horizontal goaf group in complicated combination, which verifies the reliability of dynamic response modal. A theoretical guidance has been provided for residual mining of horizontal goaf group in complicated combination.