Effects of Mineral Admixture on Electrical Resistivity and Permeability of Chloride Contaminated Mortar

Abstract

The corrosion of reinforced concrete mainly was caused by chloride contaminated. Kinds of mineral admixtures such as Fly Ash Type B (FA), Silica Fume Type A (SF), Metakaolin (MKP) and Blast Furnace Slag Type B (BB) are necessary to increase the corrosion resistance. The electrical resistivity and permeability were used on evaluating the effects of mineral admixture. The electrical resistivity and permeability of mortar were measured by using four Wenner probes and Torrent. The parameters in this study were mineral admixtures and water-to-binder ratios. Electrical resistivity and permeability of dried mortar at 91 days were studied and compared with compressive strength. According to the results, lower water/binder ratio concrete had higher resistivity than those with higher water/binder ratios. When cement was replaced by BBMKP, electrical resistivity increased fifteen times when compared to that of OPC mortar. Based on experimental results, a good relationship was obtained between results of compressive strength with electrical resistivity of mortar. The results of this study can be applied further to predict electrical resistivity of concrete when some mineral admixture with different water-to-binder ratio are provided.