THE RESISTANCE OF RICE HUSK ASH CONCRETE TO CARBONATION, ACID ATTACK AND CHLORIDE ION PENETRATION

Abstract

It was found that highly reactive rice-husk ash (RHA) with more than 40 m/g BET specific surface could be obtained by the two-step burning method. In this study, concrete specimens with different RHA blending ratios were prepared at different water-cement ratios, then cured in water, 2% HCI solution, and an accelerated carbonating chamber respectively. The results show that after the addition of RHA to the cement not only the strength of concrete is enhanced greatly but also the losses of mass and strength of the concrete cured in the HCI solution and the carbonation rate of concrete were decreased. It was also observed that the resistance of concrete to the penetration of water, air, and chloride-ion can be much improved by using RHA.