| 摘要 |
<p>A roof and wall board of concrete is to be formed in such a way that, with increased strength, it can be made relatively thin-walled. For this purpose, it is provided according to the invention that the proportion of sand in the dry mixture of the roof and wall board is low, namely is about 45%, while a high proportion of cement of about 53% is used and that reinforcing fibres are used, namely from 0.2 to 0.8% of synthetic organic or inorganic fibres and from 1 to 3% of natural organic fibres.</p> |
