Performance-based design of bridge piers under vehicle collision

Abstract

This paper introduces a novel damage ratio index (DRI) that can be used to define the expected damage due to impact scenarios of vehicles striking bridge piers. The DRI is based on the structural characteristics of the bridge and the kinetic energy of the colliding vehicle. A performance-based approach allows the designer or bridge owner to choose a target performance level based on different parameters, such as the criticality of the bridge to the transportation network or economic constraints. Detailed finite element models of the bridge piers were generated, validated, and verified against a series of available experimental and numerical results from previous research. A detailed review of the effects of different design parameters, including the pier diameter and transverse reinforcement ratio, were considered in the response of the bridge piers to collisions. For this purpose, the internal shear forces, bending moments, and displacements under different collision scenarios were studied. The review showed that the pier diameter governs the overall failure mode, the transverse reinforcement ratio controls the amount of localized damage experienced by the pier, and the kinetic energy of the impacting vehicle governs the magnitude of internal forces generated within the pier. This proposed performance-based design approach is based on the novel DRI, which enables straightforward designs of circular reinforced concrete bridge piers for a vehicle collision event without the use of extensive finite element modeling.