摘要 |
A method of lining or relining a tunnel comprises the steps of deforming a collar for insertion into the tunnel, reforming the collar to locate it in the tunnel, overlapping the edges of a pipe having a single longitudinal split to reduce its cross-sectional area for insertion into the tunnel, re-aligning the edges and expanding the pipe in the tunnel for engagement with the sleeve, and securing the edges together to retain the pipe in its expanded form. |