摘要 |
<p>A tunnelling machine which after the tunnel has been cut, allows lining segments to be attached to the sides, and which allows filling material to be injected in the gap behind the segments, is advanced hydraulically, and modifies the lining procedure when an unstable region is encountered. The process of positioning the segments is interrupted until a further stable region is met again. In the meantime, either quick setting cement or timbering is used with the segments already installed to reinforce the sides. The water pressure of the hydraulic drive for the machine is used to stabilise the unstable zone as the machine passes through. To inject the filling material, the machine uses a flexible sealing ring immediately behind the tunnelling shield, which contacts the ring of segments and another sealing ring to contain the filling material.</p> |