Analytical and numerical approaches to model cover cracking of RC structures due to corrosion

Abstract

This paper presents two different approaches to model corrosion-induced crack propagation in reinforced concrete (RC) structures. Both approaches are based on a thick-walled cylinder analogy, in which the concrete cover is subjected to the internal pressure generated by the growth of corrosion products, and both consider rust compressibility and rust diffusion into cracks. The first approach is solved numerically using finite differences to model the post-cracking softening behaviour of concrete in tension. The second approach idealises the concrete cover as either a brittle elastic or an elastoplastic material, so that it may be solved using a closed-form solution. The results obtained using each approach are compared against each other as well as against published experimental results. A parametric investigation of the influence of several variables on the results provided by the modelling approaches is also presented. The experimental data found in the literature showed reasonable agreement with predictions from the numerical and elastoplastic (analytical) models.