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Abstract
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Two identical reinforced concrete (RC) bridge piers including a rectangular and a circular
section are considered. The infuence of corrosion damage, non-stationary characteristics of
ground motions, and cross-sectional shape on nonlinear dynamic behaviour, failure mechanism and failure probability of these piers is investigated. An advanced modelling technique, capable of modelling coupled infuence of inelastic buckling and low-cycle fatigue
degradation of reinforcement, is employed to simulate the nonlinear structural behaviour
of the piers. The considered bridge piers with various mass loss ratios (as a measure of
corrosion) are subjected to a series of static pushover analyses and incremental dynamic
analyses under three diferent suites of ground motions such as, Far-Field (FF), Near-Field
With Pulse (NFWP), and Near-Field with No Pulse (NFNP). Furthermore, an advanced
matching algorithm is used to investigate the efect of non-stationary content of near-feld
earthquake records including the presence of large pulses in ground motion time series
on the nonlinear dynamic behaviour of the corrosion-damaged RC bridge piers. Finally,
fragility curves are developed for each corroded bridge pier with diferent corrosion ratios
subjected to each ground motion suite. Analyses results show that the failure mechanism
of the corrosion-damaged bridge piers signifcantly depends on the cross-sectional shape
and ground motion type. It is concluded that while both of the piers with slight corrosion
levels are much more vulnerable under NFWP ground motions than those under FF and
NFNP ground motions; the probability of failure of the extremely corroded bridge piers is
approximately the same regardless of ground motion type.
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