Abstract
A dynamic response analysis method for evaluation of the maximum and residual displacements of steel piers or frames with box sections is proposed. A “plastic deteriorating hinge” is defined as a deteriorating area in the stiffened plates, which is due to local buckling. The buckling stress, the softening stress-strain relation and the decrease in unloading stiffness of a plastic deteriorating hinge are formulated from FEM studies with shell elements, and they are implemented in the stress-strain relation of a beam element.
The maximum and residual displacements of steel frames are successfully predicted by finite displacement analyses with such beams, which can be used for evaluation of seismic performance of existing steel frames.
