Seismic risk management of highway bridges

ABSTRACT: The Italian research project S.A.G.G.I. (Advanced systems for the global management of infrastructures) is aimed at developing an integrated system for the effective management of the transport infrastructures. Bridges and viaducts can be considered as the critical elements of a road network, due to their own characteristics and the considerable consequences, in terms of both repair costs and circulation problems, implied by their degradation and damage. Besides the progressive decay of the structure, a sudden and heavy damage can occur due to an earthquake. Earthquakes of medium-high intensity have high probability of occurrence during the lifetime of a bridge in many regions, such as in Italy, where a new seismic zonation in 2003 has emphasised the seismic inadequacies of most bridges and viaducts. Moreover, the slow degradation of their structural materials can significantly change their strength and ductility and, then, increase their seismic vulnerability.