Influence of cyclic hardening characteristic on seismic performance of welded austenitic stainless steel H-section beam-column

• Published in: Engineering structures Vol. 288; p. 116210
• Main Authors: Chen, Yu, Zhou, Feng, Zheng, Shuai, Li, Jianquan, Shang, Chengzhi, Lin, Xingxin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2023
• Subjects: Beam-column; Cyclic hardening characteristic; Over-strength factor; Seismic behavior; Stainless steel; Beam-column; Seismic behavior; Over-strength factor; Cyclic hardening characteristic; Stainless steel
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2023.116210

•Investigate the influence of cyclic hardening on the seismic performance of welded austenitic stainless steel H-section beam-columns.•Extensive parametric study was performed by considering different loading histories, cross-section slenderness and axial load levels.•Existing design codes and the CSM on the prediction of the ultimate strength are evaluated.•New equations for predicting the over-strength factor and the deformation capacities are proposed. Previous studies have revealed that the cyclic hardening feature of austenitic stainless steel depended on the applied strain amplitude and exhibited unsaturation prior to failure, which greatly affected the seismic response of austenitic stainless steel structures. In view of the limited research on the seismic performance and design of structural stainless steel members, this study investigates the influence of cyclic hardening characteristic on the performance of welded austenitic stainless steel H-section beam-column under combined uniaxial cyclic bending and constant compression. The finite element (FE) models of unsaturated cyclic hardening austenitic stainless steel grade S30408 beam-columns with H-section were initially created and validated with the available test data. The effects of loading history in conjunction with the axial compressive load level and the cross-section slenderness on the seismic performance of specimens were then studied through extensive parameter analysis. Results show that the capacities of load-carrying and deformation for the austenitic stainless steel member are discrete under different loading histories. Apparently, the unsaturated cyclic hardening property of stainless steel S30408 influences the performance of the member under seismic loading. Moreover, current codified design methods and the Continuous Strength Method (CSM) underestimated the ultimate strengths of stainless steel beam-columns under seismic loading. The over-strength factor and seismic deformation capacity design formulae of welded austenitic stainless steel H-section beam-columns were finally proposed.