Some observations on the effects of corrosion on the ductility of steel members and components

To determine whether rusted steel can reliably exhibit stable ductile behavior, a number of rusted pieces taken from an old steel bridge were subjected to tension and cyclic bending tests. Specimens had up to a 60% loss of cross-sectional area due to corrosion. This limited test program revealed that, while stable hysteretic behavior comparable to that of unrusted specimen is possible, premature failure under alternating plasticity can typically develop (in spite of satisfactory ductile behavior under monotonic loading). Irregularities along the severely rusted surface apparently act as crack initiators and precipitate crack propagation throughout the section.