Effects of Slag and Fly Ash on the Durability of Acrylic Emulsion Polymer–Modified Mortar

Abstract

Acrylic emulsion polymer–modified mortar (AEPM) is widely used for repairing and maintaining the surface of existing concrete structures. In this study, the durability of AEPM was improved by using slag and fly ash. Experimental investigations, including the underwater steel ball test, rapid chloride migration test, and accelerated carbonation test, were employed to characterize the effects of slag and fly ash on the abrasion resistance, chloride penetration resistance, and carbonation resistance of AEPM, respectively. The results showed that there was a strong relation between the use of slag and fly ash and the abrasion resistance, chloride penetration resistance, and carbonation resistance of APEM: (1) the abrasion resistance of APEM first increased and then decreased with the increase of slag and fly ash; (2) the chloride-penetration resistance of APEM increased linearly with the increase of slag, but first increased and then decreased with the increase of fly ash; and (3) the carbonation resistance of APEM decreased slightly with the increase of slag and fly ash. The proper quantity of slag could significantly improve the durability of AEPM, and a suitable content of slag is 6%–12%. A prediction equation of the abrasive strength of AEPM with slag and fly ash is proposed.