Concrete beam life model based on shear strength under different states of chloride ion penetration

Concrete structures undergo a reduction in strength and ultimately premature deterioration during their life due to environmental factors. Corrosion of reinforcement is known as one of the most important factors in reducing the performance of concrete structures. Assessing the current condition as well as predicting the remaining useful life of structures is very important for providing maintenance plans. In this research, considering the limit-state function of the shear strength of reinforced concrete beams, the life model is calculated under different scenarios of chloride ion penetration. Reduction of the cross-section of longitudinal and transverse rebars, reduction of the cross-section of the concrete beam, and reduction of mechanical properties of concrete and rebar, which are known as side effects of rebar corrosion, have been considered in evaluating the life model. Stochastic properties of effective parameters in shear strength, as well as chloride ions, are also considered for the probabilistic evaluation of the life model. The Monte Carlo sampling method was used to generate the input values of the models. The results show that considering the effect of concrete scaling causes a large difference in the predicted values for shear strength of concrete beams so that in the critical case, considering the effects of concrete scaling reduces the shear strength by 20% and a more realistic estimate of the remaining life of the structure will be obtained.