New Shield Machine for Excavating Various Shaped Cross-sections Developed

Tokyo, August 21, 2008 — Kajima Corporation and Kawasaki Heavy Industries, Ltd. today announced the completion of a shield machine for the APORO-Cutter* technique, a new shield tunneling method jointly developed by the two companies . The new tunneling technique can be used for constructing tunnels with virtually any cross-sectional shape, including circular, oval and horseshoe shapes. It is suitable for tunneling through hard soil and underground obstacles.

The APORO-Cutter technique uses a high speed rotating cutter to excavate hard soil. It is a totally new technique that employs a closed-face shield machine whose front end has been fitted with a rotary cutter head on a swing frame mounted to the main rotary drum (revolving drum). The cutter head quickly rotates as it turns on the revolving drum. The cutter section comprised of a cutter head, swing frame and rotary drum can be attached to a shield machine to excavate different shaped cross-sections, resulting in reduced costs and less environmental burden.

The newly developed technique will be used for the first time in metropolitan Tokyo to construct an underground double-track section of the Tokyu Toyoko Line. The new shield machine will be transported to a construction site near the Toyoko Line’s Shibuya Station stop in Tokyo where it will be put into operation in April 2009. Construction is scheduled to be completed in 2011.

*APORO-Cutter: All Potential Rotary Cutter