ABSTRACT
In the past few years across the world, the increases in frequency and intensity of floods have significantly caused damage to property and infrastructure, particularly riverine bridges. The primary focus of this study is to evaluate the flood vulnerability assessment of riverine bridges by incorporating the effect of time-dependent scour over the service life of the structure. To achieve this, a multi-span simply supported concrete girder bridge is selected as a case study bridge, and temporal scour depth is calculated over the bridge service life using regional discharge data. A detailed 3D finite element model of the case-study bridge is developed, incorporating soil-foundation-structure interaction effects. Considering different sources of uncertainties, a set of multiple bridge models is generated, and the fragility curves are developed. The findings of this study highlight that as the bridge progresses through its service life, time-dependent scouring shows a higher scour rate in the initial years, which gradually decreases as the scour depth approaches equilibrium.
