摘要 |
A composition for making concrete which does not need plastering and may be painted or papered directly comprises a binder such as lime or cement and fine and coarse aggregates in proportion at least 45% by volume fine and at most 55% coarse, the fine aggregate consisting of granulated blast-furnace slag and/or direct process slag and/or boiler smelter-slag and/or similar slags of vitreous substance having a maximum grain size of 8 mm. and containing a total fine proportion of particles having a grain size less than 0.2 mm. in an amount 12-50% by weight of the slag, and the coarse aggregate consisting of Leca, swelling clay, sintered flue dust or smelter-slag pumice. |