Water-binder Ratio Influence on De-icing Salt Scaling of Fly Ash Concretes

摘要

The influence of water-binder ratio on de-icing salt scaling of hardened concretes with siliceous fly ash addition is analysed in the paper. The analysis made on the basis of 56 cycles scaling Boras test of air-entrained concretes. The levels of water-binder ratio (w/b): 0.45 and 0.38, the partial replacement of cement with fly ash (0, 20, 35, 50% mass of cement), and kind of siliceous fly ash in three categories of loss on ignition A, B and C were variable in concrete mixes. The results show that apart from air-entraining, which was the sufficient condition to ensure freeze-thaw resistance, also the lowest value of water-binder ratio is necessarily to ensure de-icing salt scaling resistance of fly ash concretes. Loss on ignition of fly ash has significant influence on resistance to scaling only in air-entrained concretes with 0.45 water-binder ratio.