The structural response of post-tensioned beams with bonded wires has been studied experimentally, and a numerical model is proposed. The tests simulated the effect of stress corrosion failure and development of anchorage of the wires on each side of the fracture. The residual structural performance for loading up to failure was also measured. The nonlinear finite element model with interface elements reproduces the different phases of prestressing wire breaking with rebonding and loading of the beam, taking into account local and global parameters. The distribution of damage caused by wire breaking has been assumed to occur in different locations and different failure modes were studied. Conclusions are drawn for the performance of deteriorating prestressed structures.