基于地应力实测与能量判据的深埋隧道岩爆预测

Study on rock-burst prediction for deep TBM tunnel excavation based on geostress measurement and energy criterion

根据巴基斯坦N-J水电站TBM引水隧洞地质构造和岩体赋存状况,采用套孔应力解除技术对深埋TBM隧道进行了现场地应力实测,进而依据地应力场分布差异将其分为构造和非构造应力影响区。岩石力学室内试验结果表明:砂岩的储能极限对卸载速率不敏感,在一定初始围压下基本为定值。在此基础上,从岩爆能量角度采用数值模拟分析揭示深埋隧道围岩能量分布变化规律,预测不同埋深、不同地应力场条件下隧洞岩爆的级别及规模范围。研究成果可为深部地下工程岩爆的预测提供一种新的思路。

Based on the geological structure and rock mass occurrence of TBM diversion tunnel in N- J（ NEELUM- JHELUM） Hydropower Station,the geostress measurement of TBM diversion tunnel was conducted by trepanning stress relieving technology. According to the results of geostress measurement,tectonic stress influence area and nontectonic stress influence area were classified. Rock mechanics indoor test results indicate that the maximum storage energy of sandstone,insensitive to the unloading rate,is maintained at a fixed value under a certain range of initial confining pressure. On this basis,the distribution and variation law of rock mass energy are revealed by numerical simulation in term of rock burst energy,and the level and scale of rock burst were predicted under different buried depth and geostress field. The study results provide a new approach for rock burst prediction in deep underground engineering.