Mitsui Engineering and Shipbuilding Company Limited

Toda Corporation

Makoto Ukegawa

Toru Taniguchi

Masahiro Nakagawa

Koji Tada

Ayao Siseki

Yuji Tachikawa

Disclosed is a method of making a huge elongated space of square or rectangular cross section under the ground. The outer shell of the huge elongated space is built in the form of integral arrangement of lateral shell-units having shielded passages therein. Such a huge underground space can be made without requiring any large-scale equipments on the ground. The huge outer shell can be made with accuracy and efficiency by skiving and jointing adjacent parallel lateral shell-units and by using selected lateral passage of shell-units to discharge the soil or mud removed in making the underground space.

Growing community of inventors

Tokyo, Japan

Makoto Ukegawa