| 摘要 |
PURPOSE:To continuously construct both a shaft and an adit by use of the same shield machine and shorten the constructing period by rotating a shield at a determined degree by the drive of an initial rotating jack and the separation of an inner shell from an outer shell at an adit depth, and horizontally excavating with the shaft as the foothold. CONSTITUTION:A front shield 10 is rotatably and separatably connected to a rear shield 10 and advanced by obtaining the reaction from an existing segment while excavating downward, and a segment 30 is assembled in the rear shield 20 to extend a shaft A. After the turning range is over cut by a copy cutter 14 slightly short of the constructing depth of an adit to assemble a segment of one ring portion in the front shield 10, its to top part is clogged by a blind cap 17, the shield is rotated at 90 deg. by the drive of an initial rotating jack 29 and the release of the fixation between an inner shell 22 and an outer shell 21, concrete is charged in the excessive excavation space, and horizontal excavation is carried out with the shaft A as the foothold. Hence, both the shaft and adit can be continuously constructed by the same shield machine, and the constructing period can be highly shortened. |
