ABSTRACT
This paper proposes a probabilistic framework for assessing seismic and scour effects on existing river-crossing bridge structures. The unique features of this framework include the conjunct use of probabilistic scour and seismic hazard modeling, and the definitions of seismic-scour integrated fragility and demand hazard models. Probabilistic assessment is then performed to evaluate the seismic-scour effects on a representative bridge model. The fragility results for the chosen bridge model reveal that scour tends to be beneficial in reducing structural damage at slight to moderate seismic intensities and to be detrimental in increasing collapse potential at high-level intensities. The demand hazard curves further quantify probabilistically the occurrence of local damage and global collapse, and systematically reveal the complex effects of scour as a hydraulic hazard on bridge structures.
