A new methodology for energy-based seismic design of steel moment frames

A procedure is proposed whereby input and hysteretic energy spectra developed for single-degree-of-freedom(SDOF) systems are applied to multi-degree-of-freedom(MDOF) steel moment resisting frames.The proposed procedure is verified using four frames, viz., frame with three-, five-, seven-and nine-stories, each of which is subjected to the faultnormal and fault-parallel components of three actual earthquakes.A very good estimate for the three-and five-story frames, and a reasonably acceptable estimate for the seven-, and nine-story frames, have been obtained.A method for distributing the hysteretic energy over the frame height is also proposed.This distribution scheme allows for the determination of the energy demand component of a proposed energy-based seismic design(EBSD) procedure for each story.To address the capacity component of EBSD, a story-wise optimization design procedure is developed by utilizing the energy dissipating capacity from plastic hinge formation/rotation for these moment frames.The proposed EBSD procedure is demonstrated in the design of a three-story one-bay steel moment frame.