瞬变电磁法在隧洞富水性超前探测中的应用

Application of transient electromagnetic method in the tunnel advanced watery detection

采用瞬变电磁法对新疆克州盖孜水电站引水隧洞K0+520里程前方导水构造及围岩岩性变化情况进行超前探测。现场探测结果表明:隧道掌子面前方围岩富水可能性较大,在开挖过程中涌水量可能较大;在掌子面前方50 m^65 m左右位置,出水点会转移至隧道底部;出水点在隧道底板中部靠右位置。现场开挖56 m后程中出水点从拱顶逐渐下移至底板,与探测结果相同,瞬变电磁法对小断面地下隧洞围岩富水性探测具有良好的适用性。

The transient electromagnetic method is employed to detect the hydrophobic channel and the rock lithology of the surrounding rock in front of the tunnel of Xinjiang Oblast Hydropower Station Diversion Tunnel at K0 + 520. The detected results show that: the front surrounding rock is water-rich,and the water inflow gradually increase as the excavation,the inflow point gradually change from the arch to the bottom at 50 m ~65 m ahead of the tunnel face,the inflow point would occurs at the right side in the middle of the bottom. As the excavation,the water inflow point gradually changes from the arch to the bottom at 56 m ahead of the tunnel face,which is in good agreement with the detecting results. So,the transient electromagnetic method can efficiently detect the watery characters for light section tunnel.