Comparison of three seismic design methods for plane steel frames

The force-based, the displacement-based and the hybrid seismic design methods as applied to plane steel frames are briefly presented and critically compared. The force-based seismic design method forms the basis of almost all the current seismic design codes, while the displacement-based one is a rather new seismic design method already adopted by some seismic design codes. The hybrid seismic design method is a new method that appropriately combines the best elements of both the force- and the displacement-based methods and affects considerable improvements on these elements. Advantages and disadvantages of these three seismic design methods are presented as derived first on the basis of their description and on the basis of the results of their application to three plane steel frames as compared to those coming out of inelastic time-history analyses involving eight different earthquakes.