Details

Autor(en) / Beteiligte

• Islam, Abrar
• Imanpour, Ali

Titel

Seismic stability of steel wide-flange columns in ductile moment-resisting frames: out-of-plane response and design recommendations

Ist Teil von

• Bulletin of earthquake engineering, 2023-05, Vol.21 (7), p.3493-3519

Ort / Verlag

Dordrecht: Springer Netherlands

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• This paper examines the seismic stability of steel wide-flange columns located in the first storey of Ductile Moment-Resisting Frames (MRFs) with emphasis on their out-of-plane response and proposes improved stability design recommendations for such columns. A five-storey steel MRF is first designed in accordance with the seismic provisions of the Canadian steel design standard. A subassembly consisting of the exterior bay plus half of the adjacent interior bay is then isolated from the prototype MRF, and its finite element model is constructed. The results obtained from the nonlinear response history analysis of the MRF subassembly is used to assess the stability response of the first-storey columns and verify the adequacy of a component-based column model, which is isolated from the MRF, in predicting column nonlinear cyclic response. A total of 26 seismically-compact wide-flange columns covering a wide range of geometrical parameters, including global slenderness, cross-section aspect and section width-to-thickness ratios, are subjected to cyclic strong-axis displacement and weak-axis bending in the presence of a constant axial compression load. The results of the column parametric study are used to identify column out-of-plane instability modes using strength and deformation response parameters, including base moment, axial shortening, out-of-plane displacement, and cross-section twist. Two instability modes, including out-of-plane buckling at the base and member buckling, are observed. A design equation as a function of parameters affecting the out-of-plane stability of columns with base plastic hinging, namely global slenderness, cross-section aspect and axial load ratios, is finally proposed to verify the out-of-plane stability of first-storey columns under seismic loading.