Effect of different transverse bars arrangements on the behavior of concrete columns under impact loading

Abstract

Due to the fact that common structures are designed only against gravity and seismic loads, the performance of these structures must be investigated against impact loading, in order to protect against this damage if necessary. In this paper, the effect of the arrangement of different shape of transverse bars and their spacing on the performance of beam-column element against blast loading has been studied. In this study, 13 model of concrete beam-column element with different transverse bar arrangement has been explored to examine their performance against explosions with 25 kg TNT. The finite element modeling was performed in Autodyn software and the parameters of explosion modeling, behavioral models of concrete elements and rebar, air meshing dimensions and concrete elements were determined with the results of the field test of explosion in previous studies. In this research, five type of transverse bars shape were modeled proportional to the three spacing of transverse bars. The degree of deformation and the mode of failure of the elements were compared as a measure of the performance of different states of each other. The results showed that for constant area of rebar, the element with one square tie and one link has best performance comparing to other arrangements. The maximum deformation rate in the A-1 (with one square tie ) model was 65 mm and in the D-2 model (one square tie and one link), it was 26 mm, showing a decrease of 60%.

Keywords

• near field explosion
• concrete beam -column
• transverse rebar
• nonlinear finite element
• autodyn