| 摘要 |
<p>Disclosed herein is a method for making sand compositions wherein manufactured sand particles are pretreated with a clay-mitigating polycation, such as epichlorohydrin dimethylamine or polydiallyldimethylamine, and blended with natural sand particles that have washed to remove fines such that at least 90% of the natural sand particles are retained on a 75 micron sieve. Methods of the invention also involve the use of the blended pretreated sand for making concrete wherein the sand is combined with cement, a polycarboxylate type dispersant, a further amount of clay-mitigating polycation compound, and at least one hydryoxyl or hydroxyl carboxylic acid or salt compound.</p> |
