Weak-Axis Behavior of Wide Flange Columns Subjected to Blast

Abstract

Much of past research in the civilian area on the response of civil structures to explosive loading has focused on large detonations in the far field that result in relatively uniform pressure distribution over the structure and specific structural elements. A paucity of research has been conducted that investigates the effect of explosive loading in close proximity to key structural elements. The studies that have been conducted focused primarily on loading perpendicular to the strong axis of bending that result in global deformation, but no rupture or loss of material. Through experimental testing and finite-element simulation, the present study investigates the effect of blast loading on wide flange columns loaded perpendicular to the weak axis of bending. This loading scenario is critical for such columns because the near field shock wave can rupture the web, and in some cases, lead to material loss; both conditions can potentially jeopardize the axial load carrying capacity of the column as a result of increased demands on flanges and possible local buckling of the unrestrained flanges. Therefore, this critical scenario needs to be considered for developing blast resistant measures or assessing the remaining axial and bending capacity of the column. Finite-element simulation can be used for this purpose; the analyses conducted as part of this study replicate, with reasonable accuracy, the experimentally obtained localized deformation, ruptures, and loss of material as a result of blast load, although the finite-element simulation is less successful at replicating the global deformation of the column.