Optimized maintenance strategy for concrete structures affected by cracking due to reinforcement corrosion

An approach for predicting the development of concrete cracking because of steel reinforcement corrosion and for determining risk-cost-benefit optimized maintenance strategies during the service life of concrete structures is presented in this paper. Crack evolution in the concrete cover due to expansive corrosion products is investigated at different stages during crack propagation across the cover from the reinforcing bar-concrete interface to the concrete-free surface. Crack growth over time is predicted analytically by means of a softening-cohesive model for cracked concrete. Then, a stochastic deterioration model based on a stochastic process, such as a gamma process, is adopted to assess the actual state of the deteriorating structure and to evaluate the probability of failure associated with concrete cracking. Optimal repair planning and maintenance strategies during the service life are determined by balancing the cost for maintenance and the risk of failure. The results from the worked example show that the proposed approach can correctly predict concrete crack growth over time and effectively provide a risk-cost-benefit optimized repair strategy during the service life of the structure affected by bar corrosion