Computation of the dissipated hysteretic energy requires monitoring of the lateral forces during the seismic events, which are not as practical as monitoring bridge pier deformations.
This article reports on the development of a simple damage assessment method that considers the effect of cyclic loading on the state of damage and it is merely based on monitoring the bridge pier deformations.
As pier plastic deformation and damage will absorb impact energy and also prolong the interaction time, the impact force acting on the bridge pier might not be accurately predicted with rigid and elastic pier assumption.
Under strong ground excitations, highway bridge structures may experience severe nonlinear behaviors including the yielding and plastic deformation of pier members, and sometimes the pounding between adjacent decks induced by the local failure of hinge bearings necessary for restraining the girders.
The complexities of flow and turbulence patterns as well as the pressure fields induced by the wave current attacks require a three-dimensional model to predict the deformation of piers of bridge structures.
In contrast, the conventional pier accumulates large flexural deformations leading to approximately three times the deck drift seen for the rocking pier after the second motion and eventually failing with the third motion, having acquired drift levels of more than 50 cm (or ≈ 0.5% drift ratio).
The proposed model only considers the lateral deformation of the pier caused by flexure and shear: Δ = V − P tan θ K K = 1 / 4 γ h 3 E L 3 t + h GLt Open image in new window.
Horizontal deck displacement measurements are separated into their two main components: the lateral displacement due to foundation rotation and due to the flexural deformation of the pier (δ col).
Remarkably, despite having been subjected to a sequence of three earthquakes with intensity equivalent to, or exceeding, its design earthquake and having suffered considerable foundation deformation, the rocking pier survives the excess demands imposed by the Rinaldi motion.
The plastic deformation of bridge piers were simulated by artificial plastic hinges.
