Title: A Look at Type K Shrinkage-Compensating Cement Production and Specifications

Author(s): George C. Hoff and Katharine Mather

Publication: Symposium Paper

Volume: 64

Issue:

Appears on pages(s): 153-180

Keywords: air entrainment; compressive strength; density (mass/volume); drying shrinkage; expansion; expansive cement, Type K; fineness; heat of hydration; manufacturing; shrinkage-compensating cements; slump tests; specifications; x-ray diffraction .

DOI: 10.14359/6676

Date: 7/1/1980

Abstract:
Samples of Type K shrinkage-compensating cement from all 17 mills producing that cement in 1974 were obtained and evaluated for compliance with a proposed specification for these cements. The cements were also evaluated for specific gravity, fineness, heat of hydration, and expansion and drying shrinkage in mortars. Concretes were also made with the cements and evaluated for air content, slump, compressive strength, expansion, and drying shrinkage. In general most cements had little trouble meeting the specification requirements although a few cements had difficulty meeting the restrained-expansion requi rements. The application of the proposed specification called attention to several shortcomings in the specification. Both concretes and mortars made with Type K expansive cements generally had higher compressive strengths than comparably proportioned Type II cement mixtures. Slumps of Type K cement concrete were generally less than the Type II cement control mixture. Observations of air contents in both mortar and concrete suggest that some compatibility problems between certain individual cements and air-entraining agents may exist. The data indicate that the use of Type K cements in a wide variety of different applications should pose no extraordinary problems.