Flexural Behavior of Anchor Horizontal Boundary Element in Steel Plate Shear Wall

Abstract

Steel plate shear walls (SPSWs) have been increasingly used in lateral load resisting system since the post-buckling strength of web plates was realized and considered in practical design. Diagonal tension field is formed in the web plate to resist the lateral force induced by winds and earthquakes. The force is anchored by the surrounded horizontal boundary elements (HBEs) and vertical boundary elements (VBEs) and eventually transferred to the ground. Therefore, the response of HBEs, especially anchor HBEs, is essential to ensure that SPSWs could exhibit the required strength, ductility, and energy dissipation capacity. This paper presents the results of theoretical studies into the flexural behavior of the anchor HBEs of SPSWs and can be regarded as an extension to the previous work by Qu and Bruneau (2011) and Qin et al. (2017). The boundary effect was considered to reflect the actual stress state at the HBE-to-VBE connection, which assembled the method by Qin et al. (2017). Furthermore, more proper distributions of the vertical component of tension field for the positive and negative flexure cases, respectively, were proposed comparing to the work by Qu and Bruneau (2011). The hand calculation approach for the plastic flexural capacity of the anchor HBEs was given by the summation of the contributions from the flanges and the web. The developed equations are compared with previous data and good agreement was found between them. Meanwhile, comprehensively discussions are conducted to evaluate the influence of key parameters on the flexural behavior of anchor HBE. It was found that the plastic flexural capacity of anchor HBE decreases from unity to the minimum as a result of the increase in shear force, axial force and vertical stresses. Moreover, the flexural response of anchor HBE is most vulnerable to the change in shear force. This indicates that boundary effect is significantly important and cannot be ignored in the analysis. The research in this paper provides basis for the capacity design of anchor HBE.

Keywords

• steel plate shear wall;
• anchor horizontal boundary element;
• flexural response;
• parametric analysis;
• design