厂坝铅锌矿深部矿区岩爆发生机制及危险区域划分

Rock Burst Mechanism and Danger Zone Division of Deep Mining Area in Changba Lead-zinc Mine

针对厂坝铅锌矿深部开采过程中的岩爆现象,对其岩爆发生机理进行了研究。采用AE法对矿区地应力进行了测量,掌握了深部地应力的分布及变化规律;建立小厂坝矿区三维可视化模型进行数值计算,以Barton岩爆判别标准建立矿区岩爆倾向性判断准则,对矿区的岩爆危险区域进行划分。研究结果表明,小厂坝区域的地应力以水平构造应力为主,最大水平主应力为36 MPa,属较高应力状态,水平应力是小厂坝岩爆的主要能量源泉,这与现场顶板岩爆较两帮的岩爆更为严重的现象相一致;数值模拟结果显示,强岩爆区往往出现在空区附近,且埋深越大,强岩爆倾向区域范围越大,弱岩爆倾向区域随着深度的增加有向中岩爆倾向过渡的趋势。

Aimed at the rock burst phenomenon during deep mining in Changba lead-zinc mine,the rock burst mechanism was studied.Firstly,the ground stress of mining area was measured by AE method,so as to grasp the distribution and variation law of deep ground stress.Then,a 3 Dvisualization model of Xiaochangba mining area was built for numerical calculation,the tendency criterion of rock burst in mining area was established based on the Barton criterion,and the danger zones of rock burst were divided.The results showed that the ground stress of Xiaochangba mining area mainly was horizontal tectonic stress.The maximum horizontal principal stress value was 36 MPa,which was in a high stress state.The horizontal stress was a major energy source for rock burst in Xiaochangba mining area,which was in accordance with the phenomenon that the rock burst in roof was more serious than that in two sides.The numerical simulation results showed that the area with strong rock burst often appeared near the goaf.The deeper the depth,the larger the area scope of strong rock burst tendency.And the weak rock burst tendency had a transition trend to the middle rock burst tendency with the increase of depth.