Research Progress of Geological Forward Prospecting with Seismic Method in Hard-rock Tbm Tunneling
Lei CHEN#+, Bin LIU
Shandong University, China

More and more hard-rock TBMs are applied worldwide for underground projects in the field of transportation, water conservancy, and mining, etc.  However, hard-rock TBM has poor adaptability to adverse geology, such as faults, karst caves and fractured zones. Without identification of adverse geology in advance, TBM tunneling may encounter geo-disasters such as water inrush, collapse and large deformation. Detection of these adverse geologies is an important prerequisite for the safe and efficient construction of TBM tunnels. In this talk, an active seismic method and a seismic while tunneling method will be introduced to address this requirement. For TBM maintenance stage, the active-source seismic prospecting method based on 3D observation method, the velocity inversion and depth-domain migration methods was developed; and for TBM drilling stage, the seismic detection using TBM drilling noise was improved to achieve the real-time forward-prospecting. Both methods can provide imaging of karst caves and fault within 100m ahead. The detection results are directly presented to better guide tunneling.The method has been successfully applied in field, including Yinsong Water Supply Project, the longest tunnel in Asia—Yinhanjiwei Project as well as the longest railway tunnel in China—Gaoligongshan tunnel in Yunnan province, etc. In this talk, the typical application cases will presented. On-site applications indicate the method can successfully detect major geological structures and effectively protects safety.