Experimental flexural response of prestressed concrete beams with corroded strands

The paper aims to experimentally investigate the influence of the strands corrosion on the flexural behavior of prestressed concrete beams. Potential consequences of steel corrosion can be extremely serious, since the strands are subjected to high mechanical stresses. Five prestressed beams, 3700 mm long with a 200 mm× 300 mm cross-section, were subjected to artificial corrosion, to obtain different damage levels, and then tested in four-point bending. The paper follows previous works of some of the authors on the behavior of corroded reinforced concrete and prestressed concrete beams, providing an insight into the calibration of the corrosion process and on the interpretation of the experimental results. The effects of corrosion on the ultimate strength, displacement capacity and failure mode are shown and the importance of accounting for morphological aspects of the corrosion phenomenon is highlighted. Finally, based on a simplified analytical model, some interesting considerations on the failure mode induced by localized corrosion and by prestressing action itself, are made. • Five prestressed beam specimens have been cast and tested up to failure. Four of them were artificially corroded. • The corrosion morphology and location in the wires are analysed in detailed. • The corrosion influence on the ultimate load, ductility and on the failure modes is discussed. • A simplified analytical model is introduced for the results interpretation.