On the effect of reduced boundary elements in steel shear walls

Abstract

PurposeSteel shear walls have recently received exclusive remark. Respective of most building code requirements, design of shear wall vertical boundary elements (VBEs) and local boundary elements (LBEs) against web yielding triggers exaggerated stiffness. The extent of stiffness reduction effects in boundary elements thus calls for more exhaustive investigation. The paper aims to discuss these issues.Design/methodology/approachTo this end, FEM-based push-over curves demonstrating base shear vs roof displacement, and von Mises plastic strains were scrutinized in half-scale and full-size models. Analyses were in perfect conformity with experimental data.FindingsWith reference to the AISC requirement, up to 35 percent decrease in the VBE moments of inertia could be imparted in higher levels without the ultimate load capacity nor displacement to failure being reduced. Also considered was open shear walls with reduced or minimum-design LBEs, the latter being used in continuous or abridged form. LBEs could be used with a moment of inertia 80 percent smaller than required if only used in a continuous form. The effect due to opening geometry was negligible on loading capacity but distinguished on the post-yielding buckling-induced softening.Practical implicationsLight-weight design of low- to medium-level steel structures against earthquake loads.Originality/valueWith respect to continuous walls, the results are more comprehensive than those existing in the literature in that they combine the effects due to scale and orientation (horizontal or vertical) of boundary elements. The results for open shear walls are not only comprehensive but also original in a sense that they account for the influences induced by the opening type (door or window), orientation (horizontal or vertical), and design (full-length or abridged) of boundary elements, in reduced form, on the lateral stiffness of the frame.