Flexural behavior of Corrosion-Damaged prestressed concrete beams

Abstract

This paper presents an experimental study and theoretical analysis on corroded prestressing tendons and corroded prestressed concrete beams. 68 steel strands and steel wires were artificially corroded and monotonically tested under tensile loads. Results indicated significant degradation in both deformability and strength of the corroded tendons. A bilinear model was consequently developed to characterize the constitutive relationship of the corroded prestressing tendons. Afterward, six post-tensioned prestressed concrete beams were electrochemically corroded and flexurally tested using a four-point bending set-up. Different variables were considered, including the corrosion degree, yield strength ratio and corrosion of non-prestressed rebars. It was found that, corrosion of prestressing tendons led to a deteriorated flexural bearing capacity of a beam. The cracking load, yield load, and ultimate load all decreased with the corrosion degree. Thereafter, a theoretical approach based on the stress–strain model of corroded steel tendons was proposed to predict of flexural behavior of corroded prestressed concrete beams. Good agreement with experimental results of current study and from literature was observed.