| 摘要 |
PURPOSE:To make it possible to form a top wall at the same time as tunnels in parallel by excavating channel holes between opposite upper parts of both tunnels to fill the channel holes with concrete while excavating the tunnel standing in a row. CONSTITUTION:Circular cutter plates 3 and extra small cutter plates 16 of both sides of shield excavators 1 are rotated by driving motors 6 and 22. After that, a spreader 11a of a driving jack 11 is received at the front end of a segment lining (s), and the driving jack 11 is extended. Then, the ground is excavated by the cutter plates 3 and 16 to drive forward, and the same shaped circular tunnels in (t) in parallel and arch shaped channel holes (h) having the same shape as up and down channel hole formation frames 12 and 13 are excavated. Concrete is supplied to the channel holes (h) through a concrete pressure feed pipe 20, a pushing jack 18 is operated to tamp the concrete with a press member 19, and a top wall (a) and a bottom wall (b) are formed. |
