Failure of reinforcing concrete steel ribbed bars

In order to analyse the causes of unexpected failures occurred in steel ribbed bars used in the transportation of concrete slabs for maritime works purposes, a detailed study of the material’s properties has been carried out. Full mechanical, compositional, metallographic and fractographic analyses have been performed; complementary measurements of residual stresses by X-ray diffraction techniques and finite element modelling of the in-service conditions were decisive in casting some light on the problem. The combination of maritime environment exposure and high residual stress levels associated to severe bendings could be responsible for the characteristic stress corrosion cracking failures reported in the bars.