Stiffness Demand on Stiffeners of Vertically Stiffened Steel Plate Shear Wall

Abstract

Elastic buckling of steel plate shear walls (SPSWs) vertically stiffened by either flat-bar or closed-section stiffeners is studied first to determine the required bending stiffness on stiffeners. The torsional stiffness of the stiffener is found to increase the buckling stress and reduce the required bending stiffness. The proposed equation for the elastic threshold stiffness is related to the increment of the elastic buckling stress of stiffened SPSWs over that of unstiffened SPSWs. Comparisons with previous research on stiffened plates are presented. For moderately thick and stocky plates, elastic-plastic buckling stress is used to define the threshold stiffness. It is found that the threshold stiffness based on elastic-plastic buckling stress is less than that based on elastic buckling stress. Replacing the elastic buckling coefficients with elastic-plastic buckling coefficients, the proposed equation gives good predictions for elastic-plastic threshold stiffness. The findings of this study may be helpful in understanding the real demand on stiffeners in stiffened SPSWs.