Durability of very-early-strength latex-modified concrete against freeze-thaw and chemicals

초록

This study focused on the durability of very-early-strength latex-modified concrete against freeze-thaw and chemical exposure by using water absorption, freeze-thaw resistance, deicer salt scaling, and chemical resistance tests. The experimental variables were latex content (latex solids and cement as percentages) and water-cement ratio (w/c). This study examined five levels of latex content (0%, 5%,10%,15%, and 20%) at a constant slump and three w/c's (0.36, 0.38, and 0.40) at a constant latex content of 15%. The results were as follows: the water absorption at 15% latex content was less than 50% at 0% latex content and supported the theory of a continuous polymer film that hinders the penetration of water. Within the range of this study, both the latex-modified and nonmodified concrete exhibited good freeze-thaw performance, although the latex-modified exhibited superior properties. In both the weight loss and visual evaluations, the deicer salt scaling test indicated improved performance as the latex content increased. In the chemical resistance tests, the weight loss of latex-modified concrete decreased as the latex content increased for both sulfuric and hydrogen chloride acid exposures. However, in the calcium chloride solution test, the weight change varied from a slight gain with no latex to a slight loss at 20%.