Durability of reactive powder concrete under chloride-salt freeze–thaw cycling

Abstract

The corrosion of reinforcements that results from chloride iron erosion and freeze–thaw damage is the key cause of concrete material failure. Indoor accelerated freeze–thaw cycling tests on reactive powder concrete are carried out in this study, and the mass-loss rate (MLR), relative dynamic-elastic modulus (RDEM), and compressive strength are measured in order to evaluate its durability. In addition, the microstructure and composition of the reactive powder concrete during the chloride-salt freeze–thaw cycles were analyzed using scanning electron microscopy, energy-dispersive spectroscopy, and mercury-intrusion porosimetry. The results show that the reactive powder concrete was durable under chloride freeze–thaw cycling. Furthermore, the values of MLR and RDEM indicated that the actual method is not suitable for reactive powder concrete and should be modified, and that ettringite-type erosion products are generated during the freeze–thaw cycles. The conclusions in this study are valid for specific reactive powder concrete mix.