在隧道施工过程中经常遇到断层、溶洞、突水及突泥等无法预料的地质灾害,给施工带来重大灾难和无法估计的经济损失.为了保证隧道施工安全,对掌子面前面地质情况进行准确及时的超前预报具有重大的工程价值.陆地声纳法作为地震反射法的一个变种,是一种易掌握、仪器轻便的隧道掌子面前方地质预报方法.该方法与其它常归物探方法相比,可避开许多干扰波,可单道连续采集,并且有分辨率高,偏移距小,反射能量高等特点.在详细调查某引水隧道沿线工程地质情况的基础上,结合陆地声纳的探测结果,对掌子面前方的断层、溶洞和可能较大的涌水点的位置进行了预测.结果表明该方法对断层、破碎带、溶洞的探查精度较高,对水的探查可作为辅助手段.
Unexpected geological disasters such as faults, karst caves, water and slurry gushes often happen during tunnel construction, which can bring momentous disaster and un-estimated economic loss to construction. The precise and immediate forecast in advance about geological conditions in front of the tunnel face has an important practical value in engineering. As a varia- tion of the seismic reflection method, the land sonar method is a kind of advanced geology prediction method ahead of the tunnel face. Compared with ordinary detection methods, this method has many merits such as high resolution ratio, avoiding lots of dis- turbed waves, continuous collection for single trace, high energy of reflection waves and minimum offset distance. Based on the detailed investigation of engineering geological conditions along a tunnel, the land sonar method was applied to detect faults and karst caves in front of the tunnel face. The results show that the land sonar method has a high accuracy to find faults and karst caves, which can also be an assistant method to the water detection.