Date of this Version
Proceedings of the Sixth International Conference on Protective Structures 2023 (ICPS 6)
May 14-17, 2023 : Auburn University, Auburn, Alabama, United States
Highway bridges exposed to intentional or unintentional fire followed by combined vehicle impact and air blast are at risk of significant damage and, possibly, collapse. Limited studies examining the complex effects of these extreme demands on bridge support elements and parametrizing their response and damage are found in the open literature. Research that is presented is part of an ongoing numerical investigation examining round, multi-column, reinforced concrete (RC), bridge pier behavior subject to multi-hazard scenarios involving fire, vehicle impact, and air blast. Detailed nonlinear finite element analysis models of single columns and multi-column piers supported by a pile foundation system were created using LS-DYNA. A unique multi-step modeling approach was developed to simulate their post fire vehicular impact and blast response and performance was assessed based on defined damage levels. Parametric studies were conducted to evaluate the effects of various multi-hazard scenarios and on different multi-column pier configurations. The studies first examined pier behaviors under vehicle impact and blast and then looked at the combined effects of fire followed by vehicle impact and blast on pier performance and robustness. The effectiveness with which select in-situ retrofit schemes mitigated damage was also investigated using the models by examining final failure modes. Model development steps will be summarized along with results from analyses from ongoing parametric and retrofit studies.