ABSTRACT
This paper summarizes research on assessing U.S. provisions for seismic and non-seismic design of column stiffener details in steel moment-resisting connections. The limit states of local flange bending (LFB), local web yielding (LWY), and panel zone (PZ) shear were investigated, and new column stiffener details were studied, particularly to avoid welding in the “k”-area of the column section. The research included nine full-scale pull-plate tests to study response to monotonic loading, six full-scale cruciform tests to study cyclic response, and corroborating three-dimensional nonlinear finite element analysis. Current U.S. design provisions are reaffirmed, or alternative design equations are proposed where appropriate. Specific findings for both seismic and non-seismic detailing include: column stiffeners are not required for adequate connection performance if the column section is sufficiently large; fillet-welded continuity plates are adequate; and several new doubler plate details that avoid welding in the “k”-area of the column are effective.
