Performance-Based Seismic Design Method Of Moment-Resisting Steel Frame Based On Hysteretic Energy Spectrum Under Far-Fault Earthquake

At present,the seismic design code in most countries have adopted structural elastic seismic design method based on intensity.The design seismic forceis is far lower than the actual seismic force structure suffered.The design seismic force which is specified by current seismic code is not to make the structure under seismic fortification without injury,but specifing a minimum lateral resistance level expectations make the designed structure into inelastic state under seismic fortification.Such approach that non-direct considering elastoplastic structures under seismic action is no guarantee that the structure appears strong earthquake ideal under ductile failure mode.Therefore,the structure designed by current seismic method of state under fortification and rare earthquake can not be controlled.Scholars from the United States is committed to a clear control of the structure under different earthquake intensity of behavior based on the seismic behavior of the design concept,corresponding to different intensity earthquakes create different structural states of the state standards and indicators,the expected intensity earthquake,structural damage does not exceed provisions of the state,and having the desired level of reliability.Current research on structural seismic design of theory,method has achieved many results,seismic design of buildings in some countries also included in the design of state-related content,but due to lack of technical reserves,national codes have failed to put forward simple and practical the general design methods.Taking into account the cyclic effect of ground motion acceleration of far-fault earthquake,a performance-based seismic design method of moment-resisting steel frame was proposed based on the accumulated hysteretic energy spectrum,accumulated ductility ratio,and hysteretic energy balance equation.In this paper,the calculating formulas of hysteric energy of the steel beam and column were constructed,and determining method of the cross section of steel components were also proposed.A five-story,three-span steel frame was designed based on this new design method,and the seismic behavior was evaluated by the pushove analysis and the nonlinear time history method,and the reliability of this method was proved.