Built-up battened steel columns under impact loading: Experimental and numerical analysis

In this work, experimental and numerical investigations are employed to examine the performance of the built-up battened steel columns under lateral impact load. The columns consist of four equal angle sections connected using batten plates. Drop-hammer impact tests were performed on six specimens, in which 3 impact energies were employed. Modes of failure, impact force-time histories and permanent deformations were obtained in the test. Subsequently, finite element (FE) models were established using ABAQUS, in which the strain-rate effects of steel material and initial global imperfections were considered. In addition, the validated FE models were utilized to analyze the whole dynamic response and investigate the influences of key parameters, including the impact energy, impact location, boundary condition and axial-load level etc., on the impact behaviour. A further discussion on the non-dimensional parameter of the energy absorption capacity (EAC) was conducted to qualify the behaviour of the built-up battened steel columns under impact load.