Brace design of K shape eccentrically braced steel frames

In order to study seismic-resistant characteristic of K shape eccentrically braced steel frames,nonlinear finite element analysis for five samples with different sections was performed.Analysis indicates that:(1) to ensure the link yield before the buckling of brace,the brace should have enough rigidity,(2) the brace with smaller ratio of slenderness has better hysteretic behavior,and structural ductility and energy-dissipation performance will decrease if the ratio of slenderness is too small,(3) to brace with smaller ratio of slenderness,the flange ratio of width to thickness should be emphasized while the web ratio of height to thickness should be enlarged,(4) the quality of weld should be controlled strictly,because the weld in the connection of brace and transverse beam is in high possibility of rupture.Suggestions on design and fabrication based on the finite element simulation results are presented.