A model for the evolution of concrete deterioration due to reinforcement corrosion

One of the most crucial factors affecting the service life of reinforced concrete (RC) structures attacked by aggressive ions is reinforcement corrosion. As the steel corrosion progresses, crack propagation in concrete medium endangers the serviceability and the strength of RC structural members. In this study, a nonlinear mathematical model for determining the displacement and stress fields in RC structures subjected to reinforcement corrosion is introduced. For corrosion products, a nonlinear stress–strain relation which has been previously confirmed by experimental data is incorporated in the present analysis. In formulation of the governing equations for steel–rust–concrete composite, the rational behavior of corrosion products and penetration of rust into the microcracks are considered. An analytical approach as well as an innovative meshless method, gradient reproducing kernel particle method (GRKPM), are employed for solving the nonlinear boundary value problem. A reasonably good agreement between the results of the two methods is achieved. The performance of the proposed model is then investigated through various comparisons of predicted values with experimentally observed data, and again good agreement is obtained. Moreover, the effects of the crucial parameters associated with the mechanical behavior of rust and concrete on time to cover cracking and some measures of deterioration are studied for different values of rust penetration into the microcracks.