| 摘要 |
There are disclosed apparatus and methods for casting poured concrete liners in manholes or the like wherein a collection of sheet-metal, flanged, arcuate panels (16, 17) is provided which panels can be assembled in belts of generally circular cross-section commencing from the bottom of the manhole to provide a complete form structure for casting a concrete liner with a minimum thickness of about three inches and including openings created by sectional cylindrical inserts, all of which can be assembled, then disassembled after the concrete liner has set. The method includes placing a plastic sheet material (424) around the assembled form before pouring the concrete so that the plastic sheet material will protect the resulting concrete wall. |
