| Abstract: | To alleviate some of the shortcomings associated with the statistically based inelastic spectral shapes, a rigorous method for the construction of inelastic design spectra is proposed. The method is based on several bounds which are derived from the differential equation of motion for a single degree of freedom system. Comparisons of the proposed spectral bounds with the actual elastoplastic response spectra and with the 84 per cent Newmark elastoplastic design spectra reveal that the proposed method yields a more economical, reliable and simple design aid. To demonstrate the quality of the proposed bounds, comparisons of the bounding spectra with their corresponding constant ductility elastoplastic response spectra for a number of records have been presented. |
