Corrosion impact analysis on residual life of structure using cathodic technique and algor simulation software

Abstract

Damage to the reinforced concrete structure is mainly occurring because of two reasons either due to end of service life or due to load exceeds beyond structural capacity. Along with these two reasons degradation of material property is the one more major factor which causes the risk of failure. A concrete structure constructed in an aqueous environment get exposed to the corrosion process. Consequently, this causes the generation of crack, fragilization, a decrease of bond strength between reinforcement and concrete. All these factors affection static and dynamic behavior of concrete structure reducing the service life of an affected area. Whereas service life carries the major role in the economy of a concrete structure that is why various methods have been developed in the second half of the 20th century to find out the residual life of the structure. In this proposed work, a non-destructive technique is used to predict the residual life of reinforced concrete beams having different cracking levels, as results of steel reinforcement corrosion, considering the variation produced in the dynamic behavior, through the variation of the first natural vibration frequency. Whereas to accelerate the corrosion process, impress current technique is used in which a current is externally applied to induce corrosion in reinforcement and then crack widths and vibration natural frequencies were measured. A numerical model is proposed with the help of FEM based Auto desk Algor simulation software to predict attack penetration depth. At the end, the paper is concluded by giving an effect of “water to cement ratio” and “cover to diameter ratio” on the initiation and propagation of corrosion and residual life of corroded beam specimen is graphically represented.