Abstract: This paper presents the formulation of a time-dependent seismic fragility format for bridges, as well as new insights into the
potential effects of aging and deterioration on seismic vulnerability traditionally neglected in fragility modeling, including joint impacts
of multiple component deterioration not investigated to date. The study evaluates the impact of lifetime exposure to chlorides from deicing
salts on the seismic performance of multispan continuous highway bridges, considering corrosion of reinforced concrete columns and steel
bridge bearings. ...点击查看全部>> The components’ degradation and their influence on seismic response are illustrated through three-dimensional nonlinear
dynamic analysis. A full probabilistic analysis accounting for variation in bridge, ground motion, and corrosion parameters is conducted
to develop time-dependent seismic fragility curves. These fragility curves indicate the evolving potential for component and system
damage under seismic loading considering time-dependent corrosion-induced deterioration. The results indicate that while corrosion may
actually decrease the seismic vulnerability of some components, most critical components suffer an increase in vulnerability. Quadratic
models depicting the change in lognormal seismic fragility parameters are proposed to capture the time-dependent effect of aging on the
fragility of the bridge system. Overall, the seismic vulnerability significantly increases throughout the lifetime of the representative bridge
geometry, with a 32% shift in the median value of complete damage fragility near the end of the bridge’s life.>>收起