The Application of Sodium Acetate as Concrete Permeability-Reducing Admixtures

摘要

The study is aimed to introduce the application of sodium acetate into the concrete mix for water permeability-reducing admixtures. The sodium acetate was treated as concrete admixture by dissolving in it through the water. Three kinds of concrete strength (fc' = 30 MPa, 40 MPa, and 50 MPa) and five mixture proportions of sodium acetate were involved to provide the specimens. To evaluate the performance of variation sodium acetate mixtures, a series of water permeability test was conducted on 28 days after concrete casting. A separate test of the temperature belongs to the concrete paste was measured in order to investigate the role of the sodium acetate solution for decreasing the temperature during the hydration process. The experiment results show a considerable reduction of water ingress for the lower concrete strength with the addition of sodium acetate greater than 3%. However, the opposite results were obtained for the highest concrete strength. A scanning electron microscope (SEM) test on the lowest strength can confirm the evolution of crystal structure inside the concrete pores.