Open-type tunnel boring machine and tunnel excavation method

摘要

PROBLEM TO BE SOLVED: To reduce the cost of a tunnel boring machine by employing a simple open-type structure which does not cause the settlement of a ground surface even in the case of a tunnel at a small depth.;SOLUTION: This tunnel boring machine 1 comprises a cylindrical outer skin plate 2, and a plurality of small-section boring machines 10 which are independently provided in the outer skin plate 2 in such a manner as to be capable of advancing and receding in the axial direction of the tunnel. The small-section boring machine 10 comprises: a small-section skin plate 11; an opening/closing cover 14 which is provided in the cutting face-side opening 10a of the small-section skin plate 11 so as to be openable and closable; and a boring mechanism 20 which is provided inside the small-section skin plate 11 in such a manner as to be capable of advancing and receding in the axial direction of the tunnel, and used to bore the natural ground of a cutting face from the cutting face-side opening 10a opened in the opened state of the opening/closing cover 14.;COPYRIGHT: (C)2009,JPO&INPIT