To suppress the opening width of a shaft to the minimum, facilitate combination working and enable construction period reduction and cost reduction by separating the tail part from a body part on the way in which an auxiliary shield machine enters the shaft.
The tail part 20 of an auxiliary shield machine 4 is separated from a body part on the way in which the auxiliary shield machine 4 fitted to the inner peripheral part of a large diameter primer shield machine 5 enters in a shaft 3. Next, the auxiliary shield machine 4 from which the tail part 20 is separated is combined with the primer shield machine 5 waited in the shaft 3 from rearward. Next, the primer shield machine 5 and the auxiliary shield machine 4 are integrated to be started from the shaft 3. Therefor the opening width of the shaft 3 can be suppressed to the minimum, combination working is facilitated and after integration, a sufficient machine inside space can be secured.
KAWAI KAZUNARI
MITANI NORIO
