Dynamic performance of bridge piers impacted by heavy trucks

Vehicle-bridge collision accidents often result in significant economic losses and negative social effects, with heavy trucks being the most destructive to bridge structures. Therefore, this study uses a high-precision finite element method to investigate the impact resistance of concrete bridge piers when subjected to heavy truck impact. The main conclusions of this paper are as follows: (1) When heavy trucks collide with bridge piers, two peak impact forces are generated due to engine and cargo collisions. The peak collision force generated by engine impact is 17.7% greater than that generated by cargo impact. (2) The damage to the bridge, when impacted by heavy trucks, is mainly concentrated on the affected pier. The primary damage characteristics of the bridge piers include punching shear damage at the impact point, tensile damage at the backside, and shear damage at the pier top. (3) The peak values of shear force and bending moment both appear at the bottom of the pier, and the combination of the two causes serious flexural-shear failure damage at the bottom of the pier. (4) The axial force is fluted along the pier height, and the axial force at the top and bottom of the pier is the largest, while the axial force at the middle section is relatively small. The instantaneous axial force of bridge pier will reach more than 2 times the axial force during operational period, seriously threatening the safety of bridge. Overall, this study provides valuable insights into the impact resistance of concrete bridge piers when subjected to heavy truck impact, which can help engineers and policymakers in designing more robust and safer bridges.