Investigating the behavior of hollow steel section beam under repetitive transverse impact loading

Abstract

When a load is exerted on a structural element several times, it is called repetitive loading. This type of loading causes more damage to structural elements than monotonic loading. This paper presents the effects of repetitive transverse impact loading on the weak axis of rectangular hollow steel section beam. For this purpose, three simply supported beams were tested with a constant drop weight of 75 kg and three different heights (400 mm, 800 mm and 1200 mm). Transverse impact load was exerted on each specimen 3 times repeatedly. In the numerical studies, finite element models of all specimens were developed using ABAQUS finite element analysis software. In order to obtain reliable numerical models, finite element models were verified using the experimental data. To investigate the effects of repetitive transverse impact loading on hollow section steel beam, parameters such as displacement, reaction forces, stress distributions and out of plane plastic denting were evaluated comparatively. The obtained results showed that, when the height value is increased twice as the initial height in test series RIA and RIB, the displacement value increased by 57% in the first hit, 68% in the second hit and 79 % in the third hit. Thus, it seems that the increase in the displacement value due to the increase in the damage of subsequent hits is not linear, but rather logarithmic. Finally, it was understood that with increase in the plastic deformation and displacement occurring in an element subjected to repeated impact loading, a decrement occurs in the reaction force transferred to the supports.