EFFECT OF AIR-ENTRAINING AND WATER TO CEMENT RATIO ON AIR-VOID CHARACTERISTICS IN HARDENED CONCRETE

摘要

The advanced air void analyzer (MIC-840-01) was used to study the effects of air-entraining and water to cement ratio (w/c) on the characteristics of air void in hardenedconcrete. The results show that air-entraining and w/c make significant effects on spacingfactor, mean air void diameter, specific air void area and air void size distribution in hardenedconcrete. As w/c increases, the spacing factor in hardened concrete increases and thecharacteristics of air void become worse even though there have the same air contents in freshconcrete, which will influence the frost resistance of concrete. On the other hand, when w/cand the air in fresh concrete are uniform, the air and spacing factor in harden concrete arevariant by different air-entraining.