Abstract:
Ever since the tragic events of the 9/11 attacks in New York, global infrastructures
have suffered significant damage caused by acts of terrorism, military strikes, and
accidental explosions. Coastal regions and critical infrastructure, including bridges, face a
significant threat from maritime terrorism. Furthermore, intentional car bomb explosions
in acts of terrorism and military assaults also pose substantial risks to the structural integrity
of bridges. Among the various components comprising a bridge structure, bridge piers play
a crucial role in providing vertical support. Hence, it is crucial to study the structural
response of reinforced concrete (RC) columns under blast loading.
This study involved the development of two comprehensive numerical models,
using LS-DYNA software, to analyze the air blast and underwater explosion (UNDEX)
responses of RC columns. The validation process entailed comparing the simulation results
with experimental data obtained from previous studies by Yuan et al. (2017), Yang et al.
(2019), and Zhuang et al. (2020). Both numerical models exhibited reasonably good
agreement with the experimental findings, demonstrating their reliability in replicating
real-world air blast and UNDEX scenarios. With the numerically calibrated and verified
UNDEX model, a parametric study was conducted to examine the effects of blast loads
from TNT explosive charges on RC columns. The study considered various parameters,
including stand-off distance, charge weight, and water depth. Nonlinear finite element
analysis using LS-DYNA was performed, investigating a total of 60 cases. The simulation
results provided valuable insights and findings regarding the behavior of RC columns
under different air blast and UNDEX loading scenarios. This study is particularly
pioneering in its investigation of RC columns subjected to partially submerged explosions.
Additionally, the response of RC columns for both contact and non-contact air and
UNDEX explosions were investigated.