Seismic Response Probabilistic Evaluation of Bridge Pier After Vehicle Collision

The purpose of this research is to evaluate the seismic fragility of a concrete bridge pier with high-speed collision experience. Performing probabilistic analysis and calculating the probability of exceeding in the earthquake scenario after collision is another goal of this research. To evaluate the effect of collision with different speeds, a finite element model was created in LS-DYNA software and the time history force curve was extracted. Then, a finite element model was created in OPENSEES software and by considering the effect of various uncertainties, it was aimed at calculating and presenting the fragility curve of the intact and the damaged bridge because of the car collision at speeds of 80, 100 and 120 km/h. Uncertainties include dead and live loads, strength of concrete and reinforcements, modulus of elasticity of reinforcement and seismic loads. Monte Carlo analysis is performed at different maximum accelerations and cumulative distribution function (CDF) curves of the maximum drift at each maximum acceleration are presented. Then, based on these CDF curves, fragility at different levels have been calculated. The results of deterministic analysis show that the collisions at high-speed level have a notable impact on the dynamic response of bridges. In addition, the 50% exceedance probability in moderate limit state in non-collision, and collision at 80, 100, and 120 km/h speeds have occurred at PGA of 0.6, 0.4, 0.35, and 0.1 g while, the corresponding values are 1.4, 1.3, 1.2 in extensive limit state, respectively.