Effects of Corrosion and Scouring on Barge Impact Fragility of Bridge Structures Considering Nonlinear Soil–Pile Interaction

This paper investigates the effects of corrosion and scouring on the barge impact fragility of bridge structures. A typical four-span continuous reinforced concrete (RC) bridge is selected as the baseline structure, and a detailed finite-element (FE) model of the structure is developed to simulate a barge collision. Corrosion of the bridge pier, scouring, and collision-induced soil–pile interaction are taken into account in the FE model. Surrogate models based on the response surface theory and FE model results are developed to efficiently generate the barge impact fragility surfaces using the Monte Carlo method. It is found for the baseline bridge structure that damage of the piles is not an increasing function of the barge's velocity. In other words, the use of the maximum impact velocity for the barge-impact-resistant design cannot always lead to conservative results. Besides, scouring may have a net positive effect on the pier column response and bring more damage to the pile foundation.