STUDY ON THE CARBONATION RESISTANCE IMPROVEMENT EFFECT OF HIGH-FLUIDITY AND SUPER-LOW DRYING SHRINKAGE CONCRETES USING NEW HYBRID ADMIXTURES

New admixtures have been developed for high-fluidity, super-low shrinkage concretes. The properties of fresh and hardened high-fluidity, super-low shrinkage concretes using these admixtures were examined in laboratory experiments. It was found that the concretes using these admixtures have the effect of improving carbonation resistance by the experiments. Furthermore, the cause or mechanism was examined, and it was found that the amount of pores larger than 400 or 500 Å was reduced. It is expected that the concretes will have high durability not only in terms of improving crack resistance by reducing shrinkage, but also in terms of improving carbonation resistance.