METHOD OF CONSTRUCTION OF INTAKE

PROBLEM TO BE SOLVED: To shorten the construction period and curtail the cost of construction. SOLUTION: An intake unit 3 comprising a caisson 4, a pneumatic lid 15 partitioning the inside of the caisson 4 into two sections, and working tubes 18, 18 which are erected on the upper part of the pneumatic lid 15 and incorporate pneumatic devices therein is manufactured on land. The intake unit 3 is transported on sea, and installed on a rock bed 30 of the seabed in the sea area of a work site. In this state, concrete is placed in the outer peripheral part of the caisson 4, and the working tubes 18 are used to compress the air in a space 14 on the lower side of the pneumatic lid 15 by the pneumatic devices. In this state, concrete is placed in the inner peripheral part of the space 14. The working tubes 18 are then removed, and the rock bed 30 is drilled toward the space 14 from the inside of a seabed intake tunnel 25 to connect the seabed intake tunnel 25 to the space 14. The pneumatic lid 15 is then removed, and an opening of the caisson 4 is closed with the lid. COPYRIGHT: (C)2011,JPO&INPIT