PURPOSE: To place a structure on a jacket by a method wherein a floater is fed out in water through the opening part of a fork type projection of a barge, which is thrust into a space inside the jacket, and the floater is deballasted to produce increased buoyancy at the projection.
CONSTITUTION: A fork type projection 2 of a fork type barge 2 is thrust into a space inside a jacket 18 previously built. After ballast is introduced into a floater 7, and after the floater 7 is fed out in water and secured, the floater 7 deballasted to increase buoyancy. An offshore strcuture 5 is moved to the projection 2 along rails 3 with the aid of a truck 4, and is adjusted so that the leg parts of the structure 5 are vertically alignet with the jacket 18. The barge 1 and the floater 7 are sunk through regualtion of ballast, and the structure 5 is gradually inserted into the jacket 18 for joint as its attitude is controlled.
MURAKAMI SADAHIRO
WAKIZAKA MICHIAKI
MOCHIZUKI KIKUO
