ABSTRACT
Recently, Tunnel Seismic Prediction (TSP) and in-tunnel Horizontal Seismic Profiling (HSP) have been applied to the geological estimation ahead of the tunnel face at several tunnel construction sites. However, since these methods require the use of explosives, permission to use explosives is required even for construction using a partial cutting machine or Tunnel Boring Machine (TBM), for which such permission is not required. So, we developed the seismic reflection method of predicting the geological condition ahead of the tunnel face using a non-explosive hydraulic impactor. The validity of this method was evaluated by comparing the estimated result of this method with the actual geological situation through field experiments.
