ABSTRACT
The estimation of lateral displacement demands is of primary importance in performance-based earthquake-resistant design, especially, when damage control is the main quantity of interest. In particular, the steel moment resisting frames (SMRFs) are expected to be able to sustain large plastic deformations in bending and shear. However, so that the dissipative capacity of the structure can be completely activated, it is necessary to optimize the energy dissipation and guarantee the formation of a global plastic mechanism of collapse. Such objectives are persecuted not directly through nonlinear response history analysis, but indirectly through design procedures essentially based on capacity design. These traditional design provisions may be not effective to obtain a global plastic mechanism and to avoid that interruption or damage may far outweigh the cost of the structural system. It is, rather necessary a multilevel and multi-objective design procedure based on the estimation of the global behavior of the structure in terms of lateral displacement. At this aim, this study develops a simplified seismic demand estimation procedure in which the spectral characteristics of the ground motion are related to the inelastic deformation capacity for the structure.
