Use of portland pozzolana cement to enhance the service life of reinforced concrete exposed to chloride attack

This paper discusses the improvement expected in the service life of reinforced concrete (RC) structural elements subjected to chloride-rich environments through the use of blended cement. Comparisons are made between concretes with ordinary portland cement (OPC) and fly ash-based portland pozzolana cement (PPC) at three water-to-cement ratios (w/c=0.57, 0.47, and 0.37). Through a comprehensive experimental program, the apparent chloride diffusion coefficient (Dc) and corrosion current density (icorr) were evaluated for these concretes. The study reveals that (1) although service life depends on both initiation and propagation periods, the propagation period is less significant when the severity of the environment is high; and (2) the service life of an RC structure can double if PPC is used instead of OPC when chloride-induced corrosion is critical.