ABSTRACT
Despite the propensity of long duration earthquakes in subduction zones, little attention has been paid on life-time seismic loss assessment of highway bridges that are simultaneously undergoing prolonged corrosion deterioration. Consequently, this paper investigates the combined effect of ground motion duration and corrosion deterioration on lifetime seismic vulnerability and loss assessment of highway bridges. A representative case-study multi-span simply supported bridge located in Seattle is considered, where long duration earthquakes are more likely to occur. Two sets of spectrally equivalent long and short duration ground motions are considered to perform nonlinear dynamic analyses of the three-dimensional bridge analytical model. It is observed that the consideration of the effects of long duration ground motion significantly increases the failure probability of the bridge components in comparison to the short duration record set. Additionally, lifetime corrosion deterioration is found to aggravate the influence of long duration earthquakes on the seismic vulnerability of the case-study highway bridge. The seismic life-cycle cost analysis considering regional seismic hazard curve and probabilistic repair strategies reveal significantly higher seismic losses from long duration earthquakes in comparison with short duration earthquakes.
