Seismic Behavior of Steel Frames with Deformable Panel Zones

Abstract

This paper presents an analytical study on the effect of panel zone (PZ) distortions on moment-resisting steel frame behavior. Analytical frame models were developed to study the influence of PZ distortions on frames with hinging beam and hinging column joints. A simple, trilinear analytical model was developed based on the mechanics of the column web and the flanges at the beam-column joint. Two bilinear rotational springs were needed at each joint to accurately simulate PZ distortions. Results suggest that simple analytical models that do not include PZ distortions underestimate the elastic drift and overestimate the base shear capacity for moment-resisting steel frames. Further, simple analytical models used to determine inelastic seismic behavior may underestimate the rotational ductility for beam-column joints.