Study on Detailing of Structural Steel Section on Lateral Behavior of SRC-RC Transfer Columns

Transfer columns are the essential elements in a building frame structure wherein some stories are constructed with steel-reinforced concrete (RC) columns and others with RC columns. The stories with transfer columns may suffer severe damage due to sudden changes in strength and stiffness along their heights. This study investigates the structural behavior of transfer columns subjected to axial compressive loading and bending about major/minor axes. Forty transfer columns are modeled in the finite element software ABAQUS to study their failure mechanism, lateral bearing capacity, and ductility ratios. The parameters investigated are the levels of embedment length of the structural steel, and the detailing of lateral ties and the base plate at the truncation zone in the column. It is concluded that hybrid columns have higher lateral strengths than the RC columns but exhibit limited ductility due to the sudden shear failure. The specimen with structural steel extended by 50–60% of clear column height exhibited improved ductility. The precipitous failure of the transfer column is alleviated with the provision of a base plate and anchor bolts at the end of the structural steel section.