Low shrinkage cement composition
AssigneeW. R. Grace & Co.-Conn.
InventorsBaha E. I. Abdelrazig, Ellis M. Gartner, David F. Myers
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Abstract
A cement composition capable of inhibiting drying shrinkage and cracking resulting therefrom composed of cement and an alkyl or cycloalkyl carbamate, an alkylene dicarbamate, polyoxyalkylene dicarbamate or mixtures thereof.
Claims16
A cement admixture comprising at least one compound of the formula:
- ##STR3## wherein n is 1 or 2 and when n is 1, R is a C.sub.3 -C.sub.8 alkyl group or a C.sub.5 -C.sub.6 cycloalkyl group and when n is 2, R is a C.sub.2 -C.sub.10 alkylene or an A(OA).sub.x OA group in which A is a C.sub.2 -C.sub.3 alkylene and x is an integer of from 0 to 10;
- and at least one cement water reducing agent;
- wherein the weight ratio of said at least one compound to said water reducing agent is from 0.2 to 200.
An improved cement powder composition comprising from 99 to 90 weight percent of a cement powder selected from a portland cement, blended cement or aluminous cement and substantially uniformly dispersed therein from 1 to 10 weight percent of at least one compound of the formula ##STR4## wherein n is 1 or 2 and when n is 1, R is a C.sub.3 -C.sub.8 alkyl group or a C.sub.5 -C.sub.6 cycloalkyl group and when n is 2, R is a C.sub.2 -C.sub.10 alkylene or an A(OA).sub.x OA group in which A is a C.sub.2 -C.sub.3 alkylene and x is an integer of from 0 to 10.
An improved concrete composition comprising cement, sand, aggregate and water and having substantially uniformly dispersed therein from 1 to 10 weight percent based on the cement of at least one compound of the formula:
- ##STR5## wherein n is 1 or 2 and when n is 1, R is a C.sub.3 -C.sub.8 alkyl group or a C.sub.5 -C.sub.6 cycloalkyl group and when n is 2, R is a C.sub.2 -C.sub.10 alkylene or an A(OA).sub.x OA group in which A is a C.sub.2 -C.sub.3 alkylene and x is an integer of from 0 to 10.
Dependencies are inferred from the claim text.