Failure by corrosion in PC bridges: a case history of a viaduct in Italy

The paper illustrates a viaduct collapse due to corrosion phenomena. Moreover, a contribution to the issues related to both the control of existing structures and design methods to be followed for the construction of new buildings is provided.

The objectives were achieved by in situ observations and numerical analyses. The effects of corrosion phenomena are investigated, and the progressive collapse analysis is provided to be helpful in this case.

The damages induced by corrosion phenomena have caused the collapse of the viaduct taken in to account. The performed numerical analyses were able to reproduce the effects of corrosion in terms of reduction of wires diameter.

The research is limited to prestressed concrete viaduct with post-tensioned cables.

A monitoring plan, subdivided in several phases, is suggested, to avoid critical situations as these described.

The case study brought useful information on the effects of corrosion on the decks section, showing how the technology in post-tensioned cables is usually insidious and prone to the issues relating to corrosion of the wires