Residual punching shear capacity of corroded reinforced concrete slabs

Abstract

Steel reinforcement corrosion is becoming a critical issue due to the amount of old buildings still in operation with a high probability of substantial corrosion in their reinforcements. The strength and serviceability of corroded reinforced concrete (RC) slab is remarkably impacted by corrosion. Therefore, it is vital to understand more about the punching shear mechanism of slabs subjected to corrosion effects in order to make a good prediction regarding residual capacity. In this paper, critical shear crack theory (CSCT) was further developed to predict the residual punching shear strength of corroded RC slabs, considering the deterioration of material properties induced by corrosion. The effectiveness of modified CSCT was verified by comparison with the available experimental results. In addition, a validated finite element model that considers material deterioration and bond degradation was proposed to verify the accuracy of the proposed model. Finally, a parametric study of 240 cases was conducted to investigate the effect of some important factors on the punching shear behaviour of corroded RC slabs based on modified CSCT. The outcomes demonstrated that the residual punching shear capacity predicted by the proposed model is more accurate than existing design codes. The predicted failure modes also showed fairly good agreement with the experimental results.