| 摘要 |
A movable shuttering (6) is located to define a space (14) between its outer surface and the walls of a gallery to be lined. Rapid-setting concrete is injected into the space and allowed to harden, before the shuttering is moved longitudinally of the gallery by a distance equal to its length and the process is repeated. After injection of the concrete into the space around the shuttering, the shuttering is slightly retracted before its longitudinal movement to protect the newly-cast surface. The concrete is injected longitudinally by a supply (10) with an automatic control (11) coordinating mixing of the concrete with movement of the shuttering assembly. |
