Making lightweight concrete.

摘要

Lightweight concrete incorporating expanded polystyrene beads is made by first coating the expanded beads with an aqueous surfactant solution, which preferably contains a substantive cationic surfactant, e.g. a substituted or ethoxylated quaternary ammonium compound containing a C<Sub>10</Sub> to C,<Sub>8</Sub> alkyl substituent or an ethoxylated primary or secondary amine having a C<Sub>10 </Sub>to C<Sub>18</Sub> alkyl substituent, and a non-ionic surfactant such as an ethoxylated primary or secondary alcohol or a nonylphenol - ethylene oxide condensate. The wet beads are coated with dry cement and then mixed with a further supply of cement, water and sand or aggregate to complete the concrete mix.