Steel column base connection: A joint system that rigidly or semi-rigidly couples a steel column to its concrete foundation, facilitating the transfer of axial, bending and seismic forces.

This phenomenon suggests that the SRC columns confined with 5-spirals are capable of effectively resisting the horizontal shear force caused by strong earthquake without rapid collapse.

The 61-story tower’s superstructure has a reinforced-concrete shear-wall core, which takes all lateral loads, and perimeter structural-steel columns, for gravity loads only.