Flexural deformation behaviour of locally corroded prestressed concrete beams

Flexural tests of locally corroded prestressed concrete beams (PCBs) were carried out to study their displacement behaviour. A finite-element model of the locally corroded PCBs was then established, and the influences of concrete strength, corrosion rate corrosion length, corrosion location and reinforcement rate on the displacement behaviour were analysed. The following results were obtained. The displacement reduction of the PCBs was mainly related to the corrosion rate and local corrosion will also weaken the local bending resistance of the PCB. When the steel bar corrosion rate was lower than 5%, local corrosion had little influence on the bending stiffness of the PCBs. At a corrosion rate of 15%, the corrosion rate was the main parameter affecting the bending stiffness of the PCBs. A change in local corrosion length had little effect on the prestress loss and the nominal elastic modulus of the steel strands, so the displacements of PCBs with different corrosion lengths were close. The influence of corrosion position on displacement was more significant when the corrosion rate was higher. For PCBs with a relatively low reinforcement ratio, the effect of localised corrosion on flexural stiffness was more significant.