New concrete composites incorporated with calcium acetate as admixture: The Impact of Curing Age on Strength and the Effect of Temperature on Water Absorption

Abstract

In previous work, concrete mixes incorporated with different types of acetates (inorganic and organic) were formulated, cured for 28 days in water, and then tested for compressive strength. The effect of the water-to-cement ratio and the acetate content was optimized using a central composited design based on the response surface methodology approach. The results confirmed that the optimum compressive strength was achieved for the mixes incorporated with calcium acetate (CaA) using of 0.48 water-to-cement ratio. In the current work, the effect of curing age on compressive strength and density was studied for the optimum mixes. Also, the water absorption of the mixes carried out by immersion test was assessed at different temperatures (25-55 °C). Microscopic observations were also noted. The results obtained confirmed that the compressive strength and density of the CaA-concrete mix increase with increasing the curing age. The thermodynamic study of water absorption assured the dependence of water absorption on temperature. The activation energies depicted from the Arrhenius relation and the decrease in the water absorption rate for the concrete incorporated with CaA are considered as an indicator of decreasing the porosity of the concrete mixes compared to the control mixes without CaA. The findings assured that the modified mixes with CaA are promising construction materials owing to their outstanding strength and lower water absorption rates compared to conventional concrete.