ABSTRACT
4,520 m Fujikawa Tunnel in Shizuoka Prefecture, Japan, is being driven on the New Tomei Expressways which will run from Tokyo to Nagoya for a distance of approximately 330 kilometers. Very difficult and varied ground conditions were predicted on the Fujikawa Tunnel Project. The hard rock TBM was applied to excavate a Pilot Tunnel and serve as a guide providing vital information for subsequent tunnel enlargement work. To identify these difficult ground conditions prior to encountering them in the TBM face, Kajima applied a new method of seismic tomography. A newly developed hard rock TBM excavation monitoring and control system was also been applied to collect and analyze machine data for torque, thrust and excavation speed as well as with the excavated geologic records. By combining these information, a safer and more efficient tunneling operation has been secured.
