Studies on the Chloride Permeability of Fly Ash and Silica Fume based Ternary Blended Concrete

In this investigation, the performance of chloride permeability of fly ash and silica fume based ternary blended concrete has been studied with 3.5% NaCl solution. The results have been compared with plain cement concrete considered as control concrete and fly ash based binary blended concrete. The ASTM class F type fly ash was used and 20% replacement was considered for developing the binary blended concrete. The ternary blended concrete was developed by considering the replacement of cement in binary system by 4%, 8% and 12% silica fume. The optimum replacement of silica fume was identified by conducting rapid chloride penetration tests. Macrocell current, free chloride content and chloride ion penetration depth were carried out to ascertain the performance of concrete specimens. The variable factors considered in this study were concrete grade (M₂₀, M₃₀ and M₄₀) and the curing period (28 days and 90 days) of the concrete specimens. The results indicate that binary blended concrete shows better results than the control concrete. The ternary blended concrete shows lower chloride ingress compared to both control and binary blended concrete.