Seismic demands of steel moment resisting frames with inelastic beam-to-column web panel zones

This paper intends to provide quantitative seismic response characteristics of steel moment resisting frames (MRFs) with inelastic beam-to-column panel zone joints. Two modeling approaches are proposed for this purpose along with a methodology to consider the fracture potential at the bottom beam flange in steel MRFs due to panel zone kinking. Both approaches, which are validated with available experiments, preserve the behavioral insights of inelastic panel zones. Nonlinear static and dynamic analyses are then conducted to quantify the seismic demands of 32 prototype steel MRFs while their panel zones exhibit various levels of inelastic deformations. Engineering demand parameter hazard curves are developed to interpret the results for a risk-targeted seismic performance. The results demonstrate that steel MRFs with panel zone shear distortions of 10 to 15 times the shear distortion at yield, gamma y${\gamma _y}$, have a mean annual frequency of collapse ranging from 1.5x10-4$1.5 \times {10{ - 4}}$ to 2.5x10-4$2.5 \times {10{ - 4}}$, which is up to two times lower than corresponding results with code-compliant steel MRFs (i.e., gamma