A novel frame-type crashworthy device for protecting bridge piers from vehicle collisions

Abstract

The development of different types of crashworthy devices that can alleviate the damage of bridge piers under vehicle collisions has attracted the attention of many researchers. However, the existing crashworthy devices often suffer from problems such as high cost, difficulty involved in maintenance, uneconomical expenditure for structural retrofitting after an impact event, etc. This paper develops a novel frame-type crashworthy device using relatively cost-effective steel material. Beam segments with reduced cross-sections are employed to concentrate the plasticity in certain structural components during vehicle collisions, which may facilitate structural repair after impact. Non-linear finite-element (FE) models of a colliding vehicle, of the device and of a protected reinforced concrete (RC) pier column are developed with detailed model validations to assess the effectiveness of the device for pier protection. Numerical results show that the device can absorb a large portion of the impact energy during a vehicle collision and can reduce the magnitude of the impact force and the dynamic response of a protected RC pier column very markedly.