| 摘要 |
<p>The reinforcement ribs on the underside of a concrete roofing tile (2) are formed during the manufacture thereof by directing mortar into recesses (19) in a pallet (P) on which the tile is made, compaction means (18) in the form of multi-tined wheels (18a, 18b) being provided to compact the mortar in said recesses (19) and thereafter providing a secondary layer (46) of mortar over the compacted reinforcement ribs to complete the tile in a conventional manner. A tile provided by the invention comprises reinforcement ribs which are compacted to the same degree as the remainder of the tile thereby ensuring that the finished product, when cured, has a uniform strength or substantially so.</p> |
