In this paper, the dynamic response of hollow and partially concrete-filled cold-formed steel tubular (PCFCFST) columns with elliptical cross-section under simultaneous loading of static compressive axial load and dynamic lateral impact load is investigated using finite element analysis (FEA) by ABAQUS. To ensure the accuracy of the numerical modeling, the analysis results are compared with the results of previous experimental and numerical studies. The effect of different parameters such as aspect ratio, axial load ratio, impact angle, concrete filling ratio , and wall thickness of steel tube on the behavior of PCFCFST columns have been investigated. The results of the numerical analysis showed that specimens with higher concrete filling ratios have better performance than hollow specimens. Impact angle and axial load ratio have a significant effect on the failure modes of the columns, especially when the column aspect ratio is low. As the wall thickness of the steel tube increases from 2.25mm to 4mm, the maximum displacement decreases by approximately 70%.
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