The effect and mechanism of chloride ion attack on portland cement concrete and the structural steel reinforcement

Abstract

The effect and mechanism of chloride ion attack on Portland cement concrete and the structural steel reinforcement was investigated.
At low concentrations, chloride ion has little or no effect on the physical stability of concrete structure but it causes the corrosion of the reinforcing steel in the concrete but at high concentration' especially at low temperature, it causes expansion and cracking in the concrete. The degradation is usually accompanied by formation of calcium oxychloride salts. The mechanism for this destruction was due to the thermal transformation of the calcium oxychloride salts: 3CaO CaCl₂ 15H₂O to CaO.CaCl₂ 2H₂O.


IFE Journal of Science Vol. 8 (2) 2006: pp. 131-134