摘要 |
<p>Porous lightweight building materials are made from a mixture of finely divided white lime obtained by burning pure CaCO3 and having a weight per litre of 1.03-1.15 kg., sand, water and an expanding agent, e.g. aluminium powder, by casting the mixture into a mould, causing or allowing it to set therein and then steam hardening the rigid porous structure so formed.</p> |