PURPOSE: To greatly enhance the economics by decomposing the atmospheric side conponents of a shield machine after excavation of a pit, collecting them back onto the ground, and lifting a cutter head by a crane installed on the ground in the condition that the pit is submerged with water for collection of the cutter head.
CONSTITUTION: After a pit is excavated by a vertical shield machine 1, mud feeding/ exhausting pipes, erector, cutter rotating motor, shield jack, etc., which are positioned on the atmospheric side above a bulkhead 12, are collected back onto the ground. Using a wire 22 a cutter head 3 is tied with a hook 21 sunk from a crane provided on the ground. Water is poured into the pit so that the shield machine 1 is submerged with water, and the water is put to the level which generates equilibrium with the earth pressure and subsoil water pressure acting on the excavation surface and inside of a bulkhead chamber, and the state of free water surface is generated. A ring girder 4 is separated from a bulkhead 5 using a remote control device such as a hydraulic jack, and the cutter head 3 is lifted by the crane and collected onto the ground. Thereby the cutter head and other components which are expensive can be collected, and construction of the works can be completed safely and quickly.
ODAWARA KENJI
SAKURAI HIROSHI
FUJII YOSHIBUMI
OONISHI TSUNEYASU
YOSHINO SHIGEO
WAKITA HAJIME
HIRASAWA YUKIHISA
ISHIKAWA YASUAKI
MAEHARA NOBUYUKI
WATANABE AKIRA
TAKENAKA DOBOKU
HITACHI CONSTRUCTION MACHINERY