| 摘要 |
<p>A plastic composition comprises sawdust, impregnated with an aqueous solution of caustic alkali or alkali metal silicate and allowed to stand for some hours, the sawdust being then mixed with Portland cement and a small amount of ground gypsum, gauged with a solution of calcium chloride, and moulded to desired shape. A mineral aggregate such as incinerator ash or the like may be added, and the mass may be employed with a metal reinforcement. A roughened effect may be produced by distributing burnt sand or the like over the surface before setting.</p> |
