Experimental investigation of the process of corrosion-caused cover cracking: Fid-Bau Portal

Experimental investigation of the process of corrosion-caused cover cracking

Zhang, Yanlong / Su, Ray Kai Leung

Highlights • Cover cracking is experimentally investigated with digital image correlation. • Entire process of cover cracking is experimentally recorded for the first time. • Corrosion-caused rotation of the cover is first observed. • Crack opening displacement profiles are measured. • Concrete expansion at the steel/concrete interface are measured.

Abstract Corrosion-caused cover cracking can lead to the serious deterioration of reinforced concrete (RC) structures. However, only a few experimental studies in the literature have examined the entire cracking process of specimens with a realistic configuration that consists of both the concrete cover and concrete core. Herein, the mechanism and process of cover cracking are experimentally investigated for cover and core specimens by using accelerated corrosion tests together with digital image correlation. The entire process of corrosion-caused cover cracking is experimentally recorded. The phenomenon of the rotation of the cover is first observed. Furthermore, the direction of the crack propagation, crack opening displacement (COD) profiles and the concrete expansion at the steel/concrete interface are measured. The relationship between total rust and the rust that causes expansion pressure on the surrounding concrete is examined. The test results are then used to validate a previously proposed elastic-body-rotation model for simulating cover cracking.