Large-scale underground structure and the construction construction method

摘要

PURPOSE:To improve watertightness and enable back-filling injection by forming a ring-like continuous wall out of a plurality of tunnels of small diameter built at intervals and a plurality of connecting structures built at the interval parts so as to build an underground structure. CONSTITUTION:Shafts 10 are constructed at both ends of a construction section, a shield machine 11 is carried in, drilling is begun at a plurality of positions of an underground space, and tunnels 5 of small diameter are built by lining steel segments or composite segments 12. Next, the ground is solidified by injecting chemical or driving lock bolts from the inside of the small diameter tunnels, the opposing segments 12 of the adjoining small diameter tunnels 5 are opened, and the natural ground between the respective small diameter tunnels is drilled so as to communicate to each other. Next a connecting wall 7 is welded to the steel segments 12 of the small diameter tunnels 5, reinforcement 8 is arranged inside the connecting wall 7 from the small diameter tunnels 5, thereafter concrete is filled so as to build a connecting structure 6, and hence a continuous wall 4 is ring-likely formed. Natural groung inside the continuous wall 4 is drilled so as to form an underground space.