| 摘要 |
<p>PURPOSE:To prevent the percolation of groundwater in a short time by a method in which a cylindrical shell freely projecting through the main frame of a contracted diameter position and the outside of the face plate is provided to the inner front side of a shield body. CONSTITUTION:Shield excavators are each advanced from two vertical pits to excavate a tunnel and stopped so that the cutter heads 1 are faced coaxially at the middle. Each frame contracted diameter jack 10 in both the shield excavators is extended, the movable frame 8 is turned toward the shield body 2, and the main frame 4 is contracted in diameter. The contracted diameter jack 16 of each face plate is contracted, and the cutter face plate 6 is moved to axis A side for contracting the diameter. The jacks 29 of both the shield excavators are extended, the cylindrical shell 28 is projected toward the facing, and the joints 28a of the shell 28 are coupled. The shells 28 are connected to prevent the degradation of the surrounding ground and the percolation of groundwater, and the disassembling of the shield excavator and the covering work are proceeded. The underground docking work can thus be economically performed in a short time.</p> |
