An Experimental Investigation into the Effect of Transverse Reinforcement Corrosion on Compressive Strength Reduction in Spirally Confined Concrete

Due to a small concrete cover of spiral reinforcements compared with longitudinal rebars, the corrosion of spiral reinforcements becomes earlier and more severe, leading to cracks in concrete, a decrease in confinement, an intensification of reduction in deformation capacity and ductility of reinforced concrete structures. To assess the amount of reduction in the capacity of reinforced concrete specimens in different corrosion degrees, forty-four standard cylindrical specimens with and without reinforcements are prepared to conduct an experimental investigation. The test variables include the corrosion percentage, spiral diameter, spiral pitch, and confined core diameter. Based on the experimental observations regarding the effects of corrosion on the spiral reinforcements, functional relationships associated with the compressive strength of reinforced concrete are proposed to indicate the strength of corroded reinforced concrete with respect to the strength of non-corroded reinforced concrete. The main functionality of the proposed relationships is to utilize them in order to estimate the residual strength of reinforced concrete with corroded spiral reinforcements for the rehabilitation and retrofitting of reinforced concrete structures. Results of the experimental investigation demonstrate that the corrosion up to 2.5% has a more significant effect on the reduction in confinement strength, and smaller-sized spiral reinforcements are less sensitive to corrosion.