Study On Seismic Performance Of K-shaped Eccentrically Braced Frame With Flexural / Flexural-shear Yilding Links

As a new type of structural system,eccentrically braced frame(EBF)integrates the advantages of moment resisting frame and concentrically braced frame,which has large elastic stiffness,good ductility and excellent energy consumption.Therefore,EBFs are suitable for multi-story and high-rise buildings in high seismic fortification intensity areas.To further investigate the seismic performance of EBFs,the design ideas of EBF with flexural and flexural-shear yielding links were proposed based on weakening the cross-section of links.And then,the EBFs with flexural and flexural-shear yielding links were designed.The EBF models with traditional flexural yielding links,which have the same cross-sections with the beams,were designed for comparision.Finally,based on the experiment and numerical analysis,the seismic performance of the three EBFs were studied.The research works are as follows:1)The design ideas of EBF with flexural yielding and with flexural-shear yielding links proposed in this paper were introduced.Three 10-story K-EBF models which were with flexural yielding links,with flexural-shear yielding links and with traditional flexural yielding links.The structural response was analyzed by finite element software ETABS.The dynamic characteristics,the amount of steel used,and the interstory drift of three modes were compared.2)Based on the research above,three one-bay and one-story models were designed.The scale of models was 1/2.6,then the pseudo-static experiments were conducted.The experiment results show that the three experiment models have good energy dissipation capacity and their performance meets the requirements of relevant codes.3)The seismic performance was analyzed by ABAQUS software based the experimental data.In general,the numerical simulation results were in good agreement with the experimental results.The feasibility of the numerical simulation method was verified.Based on parametric numerical analysis,the influence of the link lengths on the seismic performance of EBFs was investigated and the design suggestion of the link lengths was given.