Damage Mode and Dynamic Response of RC Girder Bridge Under Explosions

Throughout its entire lifespan, bridge constructions are susceptible to possible risks posed by military conflicts, terrorist assaults, and accidental explosions. The available research on the damage mechanisms and dynamic responses of whole reinforced concrete girder bridges under explosion loads is quite restricted. This issue is addressed by conducting high-reliability numerical simulations. The material models and corresponding parameters, as well as the numerical simulation algorithms, are sufficiently verified by comparing them with the experimental overpressure- and acceleration-time histories, as well as the damage modes from the explosion tests on 1/5 scaled two-span girder bridges. The Federal Emergency Management Agency has identified three levels of potential explosive threats: suitcase, sedan, and small moving van. These threats correspond to different cubic TNT explosive masses: 23 kg, 454 kg, and 4536 kg, respectively. The purpose of this analysis is to examine the damage modes and dynamic responses of a typical four-span prototype RC girder bridge under both below-deck and above-deck explosion scenarios. In addition, we analyzed the ability of both simply-supported and continuous girder bridges to withstand blasts, and we determined the minimum distances required for safety.