Study of water absorption and corrosion resistance of the mortar with waste marble powder

Abstract

Adding marble powder as a substitute for fine aggregate is a well-used way to utilize waste marble, one of industrial wastes. But, the addition of marble powder has an adverse impact on the corrosion resistance of mortar. In this study, hydrophobic mortar was prepared by adding superhydrophobic marble powder into mortar as an alternative material of fine aggregate. The results showed that after modification with stearic acid, the water contact angle of marble powder reached 152°, achieving a superhydrophobic state. When the content of superhydrophobic marble powder in mortar was 20%, the mortar reached hydrophobic state with water contact angle of 98°. TGA experiment demonstrated that the hydration reaction of cement was promoted by adding an appropriate amount of superhydrophobic marble powder. In the analysis of water absorption, the addition of superhydrophobic marble powder significantly reduced the water absorption of mortar, which can be reduced by 36.42% compared with ordinary mortar. Electrochemical experiments showed that the polarization resistance of mortar mixed with 20% superhydrophobic marble powder was 4×10−4 KΩ·cm2 higher than that of ordinary mortar. It is expected that this proposed method not only utilizes waste marble powder, but also improves the ability to prevent water penetration and corrosion resistance of the mortar used in the offshore environment.