Composition and method for inhibiting drying shrinkage of concrete
AssigneeW. R. Grace & Co.-Conn.
InventorsNeal S. Berke, Michael P. Dallaire, Awdhoot V. Kerkar
Life of this patent
Estimating the term…
Abstract
A concrete composition capable of inhibiting shrinkage of structural concrete structures is disclosed. The concrete is formed with an admixture composed of at least one secondary/tertiary alkanediol.
Claims19
An improved particulate cement composition comprising a mixture of a hydraulic cement powder selected from portland cement, blended cement or alumina cement and having distributed therein from 0.8 to 5 weight percent based on the cement of at least one polyol compound represented by formula:
- ##STR3## wherein each R is independently selected from hydrogen atom or a C.sub.1 -C.sub.2 alkyl;
- each R' independently selected from a C.sub.1 -C.sub.2 alkyl and n is an integer of 1 or 2.
A method of forming a concrete structure capable of inhibiting drying shrinkage and cracking resulting therefrom comprising
- a) forming a mixture of from 20 to 25 parts by weight of a hydraulic cement, from 35 to 45 parts by weight of fine aggregate, from 55 to 80 parts by weight of coarse aggregate, from 5 to 15 parts by weight of water, wherein the mixture has a water to cement weight ratio from about 0.25 to 0.6, and from about 0.8 to 5 weight percent based on the weight of the hydraulic cement of at least one polyol compound of the formula:
- ##STR4## wherein each R is independently selected from hydrogen atom or a C.sub.1 -C.sub.2 alkyl;
- each R' is independently selected from C.sub.1 -C.sub.2 alkyls and n is an integer of 1 or 2;
- b) casting the mixture into a mold;
- and
- c) curing the mixture to provide a shaped structure, which structure exhibits reduced drying shrinkage.
Dependencies are inferred from the claim text.