Evaluation of short- and longterm properties of heat-cured alkali-activated fly ash concrete

Abstract

Short and long-term properties of alkali-activated fly ash concrete namely compressive, flexural and splitting tensile strengths, modulus of elasticity, Poisson’s ratio, early age and drying shrinkage, creep, and durability performance have been investigated in this paper. Blended ordinary Portland cement-fly ash concrete was used as a reference. The average compressive and flexural strength of alkali-activated fly ash concrete at 28 days was 45 MPa and 5.8 MPa respectively; drying shrinkage and creep values were about 360 and 200 microstrain respectively at one year. The total early age shrinkage during the first 24 hours of curing was lower for alkali-activated fly ash concrete of 1460 microstrain compared to 2800 microstrain for blended cement concrete. The using of this non- Portland cement containing material for producing precast concrete units can utilize high volumes of fly ash and potentially reduce the carbon footprint of the final product.