The effect of lightweight aggregate on drying shrinkage and properties of one-part alkali activated slag concrete

Abstract In the present study, the result of slag grade, dosage of activator and aggregate combination on the compressive strength and drying shrinkage of one-part alkali-activated slag concrete was considered. Also, water curing and plastic cover curing were selected to investigate the effect of curing condition on drying shrinkage and compressive strength of this type of concrete. Two aggregate combinations, one containing lightweight fine (LAF) and normal weight coarse (NAC) aggregates and one other containing both lightweight fine and coarse aggregates, were considered for making the lightweight concrete and conducting the experimental tests. Compressive strength of the specimens were measured at 7, 28 and 90 days, as well as drying shrinkage strain up to 180 days. According to the results, in most of the mixtures, slump and setting time decreased with increasing slag and activator content, while compressive strength and drying shrinkage increased. Examination of curing condition of one-part lightweight alkali-activated slag concrete showed that drying shrinkage increased and compressive strength decreased with plastic cover curing at later age.