Title: Properties of Concrete Incorporating Low Quantity of Cement and High Volumes of Low-Calcium Fly Ash

Author(s): V. Sivasundaram, G. G. Carette, and V. M. Malhotra

Publication: Symposium Paper

Volume: 114

Issue:

Appears on pages(s): 45-72

Keywords: air-entrained concretes; carbonation; concretes; drying shrinkage; fly ash; freeze-thaw durability; modulus of elasticity; permeability; plasticizers; strength; tests; water-cement ratio; Materials Research

DOI: 10.14359/1847

Date: 5/1/1989

Abstract:
Presents results of investigations forming part of a long-term study of concrete incorporating low quantities of cement and high volumes of low-calcium (ASTM Class F) fly ash. Two types of low-calcium fly ashes from sources in Nova Scotia and Alberta were studied. For comparison purposes, a control concrete containing only ASTM Type I cement was also investigated. A large number of concrete test cylinders and prisms were subjected to determinations of strength, modulus of elasticity, drying shrinkage, freezing and thawing durability, carbonation, and permeability to chloride ions. The test results up to 1 year corroborate the results of previous investigations on concrete incorporating high volumes of low-calcium fly ash. At 7 and 28 days, the compressive strength and the modulus of elasticity were about 47 MPa and 37 GPa, respectively. Air-curing of test specimens did not seem to affect the compressive strength development significantly up to the testing period of 91 days. Resistance of all concretes to repeated cycles of freezing and thawing was found to be excellent with durability factors > 99, when tested after 14 days of the initial moist curing. The drying shrinkage strains of the fly ash concretes were comparable to or lower than that of the control concrete. Further, permeability tests carried out on one of the fly ash concretes indicated exceedingly low permeability to chloride ions at 1 year.