Estimation of lateral force contribution of boundary elements in steel plate shear wall systems

Abstract

Summary Steel plate shear walls (SPSWs) are used as lateral force‐resisting systems in new and retrofitted structures in high‐seismic regions. Various international codes recommend the design of SPSWs assuming the entire lateral load to be resisted by the infill plates. Such a design procedure results in significant overstrength leading to uneconomical and inefficient use of materials. This study is focused on the estimation of contribution of boundary elements in resisting the lateral force considering their interaction with the web plates of SPSW systems. Initially, the relative contribution of web plates and boundary frames is computed for a single‐bay single‐story frame with varying rigidity and end connections of boundary elements. Nonlinear static analyses are carried out for the analytical models in OpenSees platform to quantify this contribution. Later, this study is extended to the code‐based designed three‐story, six‐story, and nine‐story SPSWs of varying aspect ratios. Based on the results obtained, a new design procedure is proposed taking the lateral strengths of the boundary frames into account. Nonlinear time‐history analyses are conducted for 40 recorded ground motions representing the design basis earthquake and maximum considered earthquake hazard levels to compare the interstory and residual drift response and yield mechanisms of SPSWs designed as per current practice and the proposed methodology. Finally, an expression has been proposed to predict the lateral force contribution of the infill plate and the boundary frame of SPSWs. Copyright © 2016 John Wiley & Sons, Ltd.

Seismic behavior of coupled steel plate shear walls with simple boundary frame connections

“…As such, an SPSW with a considerably reduced overstrength would require a lower R factor to meet the drift requirements . A few researchers investigated the contribution of the frame action to the overall strength of planar SPSWs and C‐SPSWs and reported that a modest sharing of the lateral force between the infill panel and the frame would allow for improved material efficiency. On the other hand, when a rational design procedure such as energy‐based design and displacement‐based design is used in which the design‐base shear, unlike the conventional force‐based design approach, is calculated explicitly based on the drift demands rather than using the force modification factors, reducing unnecessary overstrength can improve the design economy.…”

Effects of configuration parameters on seismic performance of steel frames equipped with composite steel panel wall

“…However, recent researches pointed out that the boundary column would be carried large additional forces that were transmitted from SPSW or CSPSW once tension field was formed in them . Such phenomenon may result in a great impact to the boundary column, thus strong columns must be used to prevent potential collapse of the structure due to the large forces .…”

“…[9,10] Thus, many researches were conducted to investigate the seismic performance of CSPSW in experimentally and numerically.However, recent researches pointed out that the boundary column would be carried large additional forces that were transmitted from SPSW or CSPSW once tension field was formed in them. [11][12][13] Such phenomenon may result in a great impact to the boundary column, thus strong columns must be used to prevent potential collapse of the structure due to the large forces. [14] Thus, many important researches were conducted…”

Seismic behaviour of steel plate shear wall systems with staggered web configurations

“…Horizontal boundary elements are designed to restrict the formation of plastic hinges at the two ends, whereas it is desired that vertical boundary elements (VBEs) essentially remain elastic under the Design‐basis Earthquake (DBE) hazard level. Stiff and elastic VBEs ensure the better drift distribution and reduce the possibility of formation of soft‐storey mechanism in SPSWs …”

“…Stiff and elastic VBEs ensure the better drift distribution and reduce the possibility of formation of soft-storey mechanism in SPSWs. 8,9 Steel plate shear walls in high-rise buildings usually experience high overturning moment demand under lateral loading. This leads to high axial force demand on the VBEs, resulting in the unreasonably high cross-sectional requirements.…”