| 摘要 |
<p>PROBLEM TO BE SOLVED: To reliably and easily stop water at an entrance provided to a start shaft when simultaneously starting a plurality of shield machines coupled in parallel.SOLUTION: In a state that a built-in temporary segment 20 matched with a cross-sectional shape of a tunnel to be excavated is attached to a rear portion of shield machines 10a, 10b coupled in parallel, the shield machines 10a, 10b are moved toward an entrance 40 by a mobile back anchor device 50. Then, in a state that the built-in temporary segment 20 reaches the entrance 40, water is stopped by an entrance packing 30 and the built-in temporary segment 20. After that, the built-in temporary segment 20 is fixed, and while assembling a segment 60 to the rear of the shield machines 10a, 10b, excavating by the shield machines 10a, 10b is performed using a shield jack 70.</p> |
