Corrosion resistance of self-compacting concrete incorporating quarry dust powder, silica fume and fly ash

This paper presents the results of a study conducted to evaluate the corrosion resistance of self-compacting concrete (SCC) prepared using quarry dust powder (QDP), silica fume (SF) plus QDP or fly ash (FA). SCC specimens were prepared and tested for corrosion resistance, chloride permeability and chloride diffusion. The results indicated that the time to initiation of reinforcement corrosion in M4 (8% QDP plus 5% SF and w/c = 0.4) specimens and M2 (8% QDP and w/c = 0.38) specimens was more than that in M5 (30% FA and w/c = 0.4) specimens. The corrosion current density on steel in the SCC specimens was very low in the initial stage of exposure to 5% NaCl solution and it increased with increasing period of exposure. Corrosion activation was noted on steel in M1, M3, and M5 specimens. However, it was not noted in M2 and M4 specimens even after 990 days (33 months) of exposure. The chloride permeability in SCC specimens incorporating QDP or FA was moderate and it was low in the specimens incorporating QDP plus SF. The lowest diffusion coefficient was noted in M2 specimens while it was the highest in M5 specimens. (C) 2012 Elsevier Ltd. All rights reserved.