地震作用下采空区群围岩动力响应特征研究

Dynamic response of surrounding rock of goaf group under seismic loading

为探究地震对采空区围岩及矿柱的动力影响,利用FLAC3D软件模拟地震作用下采空区群围岩的动力响应过程,通过获取围岩在地震作用过程中每一时步的最大、最小主应力,分析地震作用前后采空区顶板、底板、矿柱及边墙的剪切屈服和张拉屈服应力值的变化特征。结果表明:地震过程中,空区中心区域应力稳定性最好,远离中心区域应力波动变大;地震后,空区顶板、底板的抗剪切能力稍有下降,抗拉能力显著下降,边墙的张拉破坏面积变大。

To research the dynamic response characteristics of goaf surroundings and pillars under seismic loading,dynamic response process of goaf group is simulated by FLAC3 Din this paper. Based on the maximum and minimum principal stress of every step obtained during seismic action,the variation characteristics of the shear and tension failure stress for the roof,the floor,pillar and side wall around goaf group are analyzed. The results demonstrate that during the seismic action,the central region stress of goaf is most stable and the stress fluctuation become larger away from the central region,after the seismic action,the shear resistances of the goaf roof and floor slightly reduce and the tensile resistances obviously decrease. At the same time,the tensile failure area of the side wall becomes larger.