Title:
Effect of Fly Ash Addition on the Corrosion Resisting Characteristics of Concrete
Author(s):
Mohammed Maslehuddin, Huseyin Saricimen, and Abdulazizi Al-Mani
Publication:
Materials Journal
Volume:
84
Issue:
1
Appears on pages(s):
42-50
Keywords:
admixtures; cements; corrosion; corrosion resistance; fly ash; sands; water-cement ratio; workability; Materials Research
DOI:
10.14359/1976
Date:
1/1/1987
Abstract:
Reports results of experiments evaluating the corrosion resistance of plain and fly-ash concrete mixes. Variables were fly-ash additions of 0 and 20 percent as cement replacement and four cement contents. Data were developed both for constant water-cement ratio and constant-workability concrete mixes. The corrosion resistance of concrete samples in which fly ash replaced an equal quantity of sand was also investigated. Samples were immersed in a 5 percent sodium chloride solution for more than 1000 days and corrosion resistance was evaluated by monitoring the half-cell potentials and measuring the corrosion rate of embedded steel using electrochemical techniques. Results show that addition of fly ash is effective in inhibiting corrosion of reinforcing bars. The corrosion resistance of concrete samples in which fly ash was used as an admixture seems to be better than those in which it was used to replace cement. The superior performance of fly-ash concrete samples in inhibiting corrosion of reinforcing steel is attributable to the densification of the cement-paste matrix due to pozzolanic action in the fly-ash concrete mixes.