Design of yielding or friction-based dissipative bracings for seismic protection of buildings

The problems of designing dissipative bracing systems, based on yielding or friction mechanisms, for the seismic protection of buildings, either for new structures or the retrofitting of existing buildings are considered. After introducing a one-degree-of-freedom (one-DOF) model of a building equipped with dissipative bracings, inelastic response spectra, useful for designing the bracings, are considered. The extension of the design methodology to multi-DOF systems is also considered, paying particular attention to the distribution of stiffnesses and strengths within the structure. The results of a broad parametric investigation of simple shear-type models are discussed.