闽西南某隧道高地应力特征及隧道岩爆预测研究

Case Study on High Ground Stress Behavior and Rock Burst Prediction of Tunnels

为了更方便地进行闽西南某隧道的岩爆预测与预防工作,首先,阐述了Heok-Brown岩体强度估算理论和基于修正的Sheo-rey模型的工程区地应力场预测方法。在此基础上结合隧道工程地质调查资料和地应力实测结果,分析了隧道围岩强度,预测了隧道工程区沿线的地应力大小,评价了工程区的地应力状态,结果表明该隧道大部分处于高地应力区。同时,利用强度应力比法对高应力作用下围岩中可能发生的岩爆进行了预测,并且与已发生的岩爆情况进行对比,表明该预测与实际情况一致性较好,证明了本文所采用方法的可靠性。

A rock burst prediction theory based on in-situ stress is presented in this paper. A tunnel located in southwest of Fujian, China is studied to prove the reliability of the theory. Firstly, the rock strength estimation theory based on Heok -Brown strength criterion and the rock stress prediction theory according to modified Sheorey model are presented and illustrated. The strength of the rock mass of the mentioned tunnel is analyzed on basis of the geotechnical investiga- tion data and in-situ stress, and the stress magnitude along the whole tunnel is predicted. After the stress data are obtained, the stress state is evaluated. The results show that most of the tunnel is located in the high stress area. At the same time, the widely-used strength-to-stress method is used to predict the possible rock burst during excavation. The comparison between with the prediction results and the actual rock bursts shows that the prediction results coincide well with the actual conditions.