CUTTER DISC OF DIFFERENT DIAMETRICAL SHIELDING MACHINE, UNDERGROUND JOINING DEVICE FURNISHED WITH IT AND ITS CONSTRUCTION METHOD

摘要

PURPOSE:To reduce construction cost by way of shortening a construction period by mechanically securing water stopping of a tunnel joining part without requiring auxiliary engineering. CONSTITUTION:A shielding machine main body 9 free to relatively move in the axial direction of a skin plate P is provided on a small diametrical shielding machine S1, a tube seal 10 is provided on the inner periphery of a head end part of this skin plate P, and a cylindrical body 4 to seal between a rear surface of a cutter disc D1 and a shielding machine main body 5 and a water stop ring 6 having a tube seal 8 on the inner periphery of the head end part are provided on a large diametrical shielding machine B. A circular joining part 1 having a seal surface 1a of an outside diameter smaller in diameter than an inside diameter of the the skin plate P of the small diametrical shielding machine S1 and roughly matching with it is decentered in the axial direction from the front surface of the cutter disc D1 and provided recessed, the head end part of the skin plate P is positioned at this joining part 1, the inner periphery of the water stop ring 6 is positioned on the outer periphery of the cylindrical body 4 and it is sealed with the tube seals 8, 10.