Seismic performance evaluation and design of resilient knee braced frames equipped with shape memory alloy knee braces and replaceable energy-dissipating connections. (15th May 2023)

• Record Type: Journal Article
• Authors: Qiu, Canxing; Jiang, Tianyuan; Peng, Lingyun; Liu, Jiawang; Du, Xiuli
• Is Part Of: Engineering structures. Volume 283(2023)
• Publication Date: 2023-05-15
• Subjects: Knee braced frame -- Shape memory alloy -- Replaceable connection -- Seismic performance -- Seismic design method; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2023.115918
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: A novel knee-braced frame with SMA KBs and RED connections is proposed. The knee-braced frames have minimal residual deformations after strong earthquakes. A design method is proposed for the novel frame. Abstract: This paper proposes a novel seismic resilient knee braced frame (KBF) and focuses on seismic performance evaluation and design. In this novel system, the shape memory alloy (SMA) knee braces (KBs) and replaceable energy-dissipating (RED) connections are the key components. The SMA KBs mainly provide self-centering capacity, and the RED connections mainly offer energy-dissipating capacity. To reveal the seismic performance characteristics, the 3- and 6- story KBFs are selected as the example structures. The proposed systems are designed by a modified performance-based plastic design method, which distributes the seismic energy to the SMA KBs and the RED connections by defining an energy distribution factor p . In what followed, nonlinear static and nonlinear time history analysis are conducted. It indicates that these systems could well meet the prescribed performance targets, although they are designed using different p values. In current work, the potentially optimal p value is found to be 0.1, which represents the case where 10% of seismic energy is allocated to the SMA KBs. The advantages of the novel KBF are twofold: 1) the consumption of SMA material is significantly reduced, because the RED connections are the major damping source; 2) the damaged RED connections can be conveniently repaired or replaced, because the frames could nearly return to original position, owing to the SMA KBs.