Accumulative deformation-based design method for special concentrically braced frames with H-section braces

Accumulative deformation-based fracture models of braces have been developed by researchers for nearly 30 years. These models are used to predict the fracture of braces in a specific time-history analysis of SCBF. However, no attempt has been made to explore statistical accumulative deformation demands of braces under severe earthquakes. Eight SCBF models are designed in this paper for nonlinear time-history analysis to summarize the accumulative deformation demands of SCBF braces. Meanwhile, accumulative deformation-based fracture models of SCBF braces with H-section are proposed by experimental data. Accumulative deformation demands of braces are in good correlation with hysteretic energy demands according to the results of time-history analysis. Hysteretic energy spectrum, energy demands, and accumulative deformation demands of braces are set up in this paper. The method is proposed by balancing the accumulative deformation demands and accumulative deformation limit index of braces. Finally, an example designed by the proposed method is given. Configuration detailing parameters of braces is not only determined by expected ductility but also the strength of SCBF according to the result of the example. The proposed design method can help designers to determine the configuration detailing parameters of braces complied with the strength of SCBF.