动载下巷道围岩微震响应特征及支护研究

为探讨动载下深部巷道围岩变形特征，采用微震监测系统、顶板动态监测仪及FLAC3D 数值模拟软件研究深部工作面回采中微震活动特征及巷道变形破坏特征，模拟动载前后巷道围岩及支护体力学响应特性。研究结果表明:微震事件分布与累计损失能量均呈现出明显的3阶段特征，与工作面开采过程出现的初次来压、采空区初次见方和遇见断层现象相对应；微震事件的分布在时间和空间上具有一致性；动载下顶板破坏程度大于底板及两帮；动载扩大了巷道围岩塑性区范围，改变了围岩的受力状态，增大了围岩的变形量与支护体的受力；通过增加锚杆直径、长度、排距及提高预紧力对支护结构进行优化，现场监测数据表明，优化后支护方案保证了围岩的完整性，限制了围岩的变形，减小了锚杆受力，能够有效控制采动影响下巷道围岩的变形，对采动影响下深部巷道维护保证煤矿安全生产具有参考应用价值。

Study on micro seismic response characteristics and support technology of roadway surrounding rock under dynamic load

In order to discuss the deformation characteristics of surrounding rock in the deep roadway under dynamic load,the micro seismic monitoring system,the roof dynamic monitoring instrument and the FLAC3D numerical simulation software were used to study the micro seismic activity characteristics and the deformation and failure characteristics of roadway in the deep mining face,and the mechanical response characteristics of the surrounding rock and support body before and after the dynamic load were simulated.The results showed that both the distribution of micro seismic events and the cumulative energy loss presented the obvious three stage characteristics,which were corresponding to the phenomena of the first weighting,the first square and fault encountered in the goaf during the mining process of working face.The distribution of micro seismic events was consistent in time and space.The damage degree of roof under the dynamic load was greater than those of floor and both sides.The dynamic load enlarged the range of plastic zone in the surrounding rock of roadway,changed the stress state of surrounding rock,and increased the deformation amount of surrounding rock and the stress of support body.The support structure was optimized by increasing the diameter,length and row spacing of bolt and increasing the pre tightening force,and the field monitoring data showed that the optimized supporting scheme ensured the integrity of surrounding rock,restricted the deformation of surrounding rock,and reduced the stress on the bolt.It can effectively control the deformation of surrounding rock of the roadway under the influence of dynamic disturbance,which has reference and application values for the maintenance of deep roadway under the influence of dynamic disturbance and ensuring the work safety of coal mines.