Corrosion behavior of reinforcing bars in cracked reinforced concrete pile before and after CFRP wrapping

Abstract

Due to the drying-wetting cycle caused by the ocean tide, the pre-stressed reinforced concrete (RC) piles serving in the splash zone of the seaport wharf have more serious chloride-induced corrosion problem, resulting in urgent need of repair and maintenance of those RC piles by carbon fibre reinforced polymer (CFRP). In this paper, corrosion behavior of the reinforcing bars in cracked RC pile before and after CFRP wrapping is studied, where the RC piles were simulated by the cylinder specimens with embedded steel bar in the centre. The maximum corrosion crack widths were designed as 0.1mm, 0.15mm, 0.2mm, 0.25mm, and 0.3mm. Before CFRP wrapping, the concrete surfaces were treated by corrosion inhibitor and CFRP wrapping. Results show that, CFRP wrapping repair after corrosion inhibitor treatment and CFRP wrapping directly on the concrete surface, have a good effect on preventing the internal reinforcement from continually being corroded by chloride ions when the corrosion crack width in the concrete cover of the RC specimens is 0.25mm, especially for the former method.