In this paper, attempts have been made to analyse the corrosion characteristics of three kinds of cements, namely ordinary Portland cement (OPC), pozzolana Portland cement (PPC) and 25% fly ash replaced in ordinary Portland cement (FA) by designing two grades of concrete, M20 and M40 mixes under accelerated exposure conditions. Reinforced concrete slabs of size 900 mm x 180 mm x 100 mm were cast, cured and pre-cracked to crack width of 0 mm and 0.10 mm, exposed to accelerated testing conditions in 3% NaCl environments and evaluated for their corrosion resistance using various electrochemical tests like open circuit potential, linear polarization technique, free chloride, alkalinity and weight loss measurements and the results obtained were discussed in detail. (c) 2007 Elsevier B.V. All rights reserved.