Effects of duration of moist curing on concrete made with blended cements or pozzolans. Report 2, Laboratory investigations of 6-in.-aggregate concrete
Tynes, W. O. (William O.)
Technical reportAbstract: Seven air-entrained concrete mixtures containing 6-in. maximum size limestone aggregate were tested to determine if the 21-day moist-curing requirements for concrete containing type IV portland cement, a pozzolan, natural cement, or slag cement could be reduced to 14 days as required for type II portland cement and portland blast-furnace slag cement (type IS) concrete. One of the seven mixtures was a reference mixture containing type II portland cement as the only cemehtitious material, while the other six mixtures were proportioned as follows: two mixtures with fly ash pozzolan and type II portland cement; one mixture with calcined shale pozzolan and type II portland cement; one mixture with natural cement and type II portland cement; one mixture with a different type II cement; and one mixture using portland blast-furnace slag cement. Specimens made from each mixture were cured under six different curing conditions, and tested for compressive strength, abrasion resistance, and permeability. Prisms were made for four of the curing conditions for exposure tests for resistance to freezing and thawing. The results of the compressive strength and permeability tests indicate there were no relative differences between the 14- and 21-day moist-cured specimens tested at both 28 and 90 days age regardless of the cementing material of the mixtures. The abrasion loss values for the 14-day moist-cured specimens of all mixtures tested were somewhat higher at 28 days test age than those of the specimens moist cured 21 days. However, at 90 days only three of the seven mixtures moist cured 14 days had higher values than those moist cured 21 days.
Concrete Laboratory (U.S.)Engineer Research and Development Center (U.S.)
Aggregates; Concrete curing; Concrete testing; Portland cements; Portland pozzolan cements; Portland slag cements
Technical report (U.S. Army Engineer Waterways Experiment Station) ; C-69-6 rept.2.
Approved for public release; distribution is unlimited.