Title:
Distinguished Impact Response of Hollow Reinforced Concrete Beams under Impact Loading
Author(s):
Thong M. Pham, Tin V. Do, and Hong Hao
Publication:
Symposium Paper
Volume:
347
Issue:
Appears on pages(s):
106-126
Keywords:
Impact response; Concrete beam; Drop-weight tests; Numerical Simulation; Hollow beams; Shear Failure
DOI:
10.14359/51732660
Date:
3/1/2021
Abstract:
This study experimentally and numerically investigated the impact responses of reinforced concrete (RC)
beams with a rectangular hollow section (HCB) in comparison with a rectangular solid section (SCB). Experimental
tests of the two types of RC beams were firstly conducted under the drop-weight impact of a 203.5-kg-solid-steel
projectile. Numerical models of the beams under impact loads were then developed in the commercial software namely
LS-DYNA and carefully verified against the experimental results. The numerical models were then used to investigate
the stress wave propagation in the two beams. The effect of the top flange depth, contact area, and impact velocity on
the impact responses of the beams was also investigated. The experimental and numerical results in this study showed
that although the two beams were designed with similar reinforcement ratio, their impact responses were considerably
different, especially when the shear failure dominated the structural response. The HCB exhibited a smaller peak
impact force but higher lateral displacement than the SCB when these beams were subjected to the same impact
condition. Besides, more shear cracks were observed on the HCB while that of SCB has more flexural cracks.
Furthermore, the decrease of the top flange depth of the hollow section and the increase of the impact velocity changed
the failure modes of the two beams from flexural failure to shear failure with concrete scabbing. The change of the
contact area also shifted the failure mode of the beam from global response to direct shear, inclined shear, punching
shear and concrete scabbing at the top flange of the section close to the impact location.