10. Design Using Advanced Analysis

A rational and efficient seismic design method for plane and space steel moment resisting frames using advanced methods of analysis is presented. This method employs an advanced dynamic finite element analysis working in time domain that takes into account geometrical and material nonlinearities and member and frame imperfections. Seismic actions are in the form of accelerograms compatible with the elastic response spectra of EC8 for three performance levels. The design starts with assumed member sections for the frame, proceeds with the checking of drifts, member plastic rotation, damage and plastic hinge pattern for the three performance levels considered here and ends with the adjustment of member sizes iteratively so as the above response parameters to satisfy their limit values for every level. Thus, the method can sufficiently capture the limit states of displacements, strength, stability and damage of the structure and its members so that separate member capacity checks through the interaction equations of EC3 or the use of the approximate behavior factor of EC8 are not required. Numerical examples dealing with the seismic design of plane and space steel moment resisting frames are presented to illustrate the method and demonstrate its advantages.