Improving chloride ion penetration resistance of cement mortar by strong base anion exchange resin

Abstract

How to improve the chloride penetration resistance of reinforced concrete in marine environment has always been an important research topic. In this paper, based on the adsorption properties of strong basic anion exchange resin (SB-AER) for chloride ion, SB-AER, silica fume (SF) and fly ash (FA) were milled into ternary admixtures with particle size less than 75 μm. The effect of SB-AER on chloride ion penetration resistance of mortar was studied. In this experiment, the mechanical properties and compactness of mortar with different SB-AER content were tested by pressure testing machine and ultrasonic nondestructive flaw detector. The microstructure of mortar was observed by scanning electron microscope (SEM). The chloride ion binding capacity of mortar with different SB-AER content was qualitatively and quantitatively analyzed by chloride ion selective electrode method. All the results show that under the appropriate SB-AER content, the ternary admixture can effectively improve the chloride penetration resistance and mechanical properties of mortar. SB-AER-3 group (SB-AER, SF and FA are 3%, 5% and 10% of cement weight, respectively) has the best performance in these two aspects.