冲击地压与区域构造应力环境相关性及其应变响应特征

Correlation between rockburst and regional tectonic stress environment and its strain response characteristics

为探明灾源体及其与周边相关区域构造应力环境之间的协同机制和作用机理,在华亭矿区建立了针对冲击地压监测的钻孔应变观测系统,并观测到了矿区内较大规模冲击事件和若干次天然地震的应变响应。实测表明,构造型冲击地压孕育及诱发过程所涉及的地层尺度要远大于传统的采场和采动影响范围;冲击地压引发的钻孔应变同震响应呈"阶跃"和"振荡"2种模式,冲击规模、观测点与震源的距离不同,响应模式也不同;灾源体与相关区域地层之间存在着"链式"相关机制;对天然地震的观测结果与之类似;初步验证了通过开采扰动的区域应力或应变效应观测来探索冲击地压孕育机理的可行性。

In order to ascertain the coordination mechanism between the source structure of rockburst and the tectonic stress environment, a borehole strain observation system was established specifically for rockburst in Huating mine, and the strain responses of large-scale rockburst events in the mining area and several natural earthquakes occurred recently were successfully observed. The observation results indicate that the stratum scale involved in the preparation and triggering process of tectonic rockburst events on a large scale is larger than the influence scope caused by traditional working site and mining. There are two borehole strain response patterns of “step” and “oscillation” caused by rockburst in the surrounding areas. While the scale or distance of observation point from rockburst source is different, the borehole strain response model is different. There is a related “chain” mechanism between rockburst source and relevant area, which is similar to the observations resulting from natural earthquake. The results preliminarily verify the feasibility of making observation of regional stress or strain effect of mining disturbance to explore the rockburst inoculation mechanism. © 2016, Editorial Office of Journal of China Coal Society. All right reserved.