要进行大尺度采空区衍生动力学灾害的准确预测预报,必须进行煤岩破裂与演化为动力学失稳的定量化实验的前期研究。大柳塔煤矿1^-2煤处于厚风积沙、浅埋深、薄基岩工程与地质环境中,要实现6m厚煤层一次全厚开采,采后形成大范围采空区上覆煤岩破裂并演化为动力学失稳,极易诱发衍生灾害。基于对1^-2煤破裂失稳的声发射相关实验,综合分析煤岩破裂声发射总事件、能率与时间的之间的定量关系,包括加载上升阶段、初始破裂阶段、加速破裂阶段、破裂失稳后能量下降阶段与回弹阶段,这有助于确定合理的失稳前兆判据,以期对开采过程中诱发动力灾害的危险源在线辨识及预警提供定量化预报。
To accurately predict the dynamical hazard of a large scale mined-out area, the quantitative experiment on unstable crack propagation and dynamical destabilization on coal-rock have been fulfilled previously. The No. 1^ -2 coal locates thick-sand on surfacef and shallow-depth and thin rock-base engineering geological environment. Large scale mined-out area will be caused once to mine coal thoroughly (6m) at Da-Liu-Ta coal mine in Shanxi province. The overburden coal-rock will collapse and result in destabilizing effect so as to derive dynamic hazard easily. Based on the AE No. 1 ^-2coal crack growth, the quantitative regularity of total-AE-event and interrelated experiment on time, energy-rate and time has been comprehensive analyzed respectively. The process includes rising stage, initial crack stage, accelerating damage stage, after damaged and anti-elastic energy stage. These characteristic regularity will be regarded as collapsing load foreboding evidence so as to on-line identify of mining derived dynamic hazard and quantitative predict.