Research on nano-concrete-filled steel tubular columns with end plates after lateral impact

Abstract

This paper presents thirteen square columns to study the behavior of nano-concrete-filled steel tubular columns with end plates after lateral impact. The failure modes of the square columns subjected to lateral impact damage or not subjected to lateral impact damage were compared. The lateral impact loading height, steel tubular thickness, and column height were set as the test parameters in these tests. The effects of test parameters on the ultimate capacity, initial stiffness, and ductility of columns are discussed in this paper. The bearing capacity of square columns is decreased because of the lateral impact loading which can also be concluded from the test results. And with the steel tube thickness increasing, the bearing capacity and initial stiffness of columns are increased and ductility has no obvious change. However, with the column height increasing, the bearing capacity and stiffness of columns are decreased and ductility is increased. Furthermore, the strain development of the columns under axial compressive loading is also discussed in the paper. The results indicated that the corner of the square column is more easily damaged under compressive loading. According to the test results, the calculated formula is proposed to predict the ultimate capacity of nano-concrete-filled steel tubular columns with end plates after lateral impact. The calculated results have a good agreement with the test results.