THIMBLE MULTICAST INSTRUMENT IN DRILL HOLE AND ITS APPLICATION TO TUNNELLING ENGINEERING
XU Jin1，2，ZHANG Zhilong1，2，WANG Lansheng3
(1. State Key Laboratory of Hydraulics and Mountain River Engineering，Sichuan University，Chengdu，Sichuan 610065，China；2. College of Water Resources and Hydropower，Sichuan University，Chengdu，Sichuan 610065，China；3. Institute of Engineering Geology，Chengdu University of Technology，Chengdu，Sichuan 610059，China)
Abstract：According to the deep-buried long tunnels through mountains，such as the Erlangshan tunnel and the Xuefengshan tunnel，the thimble multicast instrument in drill hole and its installing and testing techniques，which are suitable for monitoring the loose deformation of surrounding rock in time during the construction，have been developed and invented. Practical engineering application shows that it has many merits，such as obtaining materials locally，manufacturing easily，being installed and testing quickly，powerful anti-interference capability and accurate testing result. The instruction will be used in tunnelling engineering and other underground engineering extensively.
