DEMAND SPECTRA FOR ENERGY BASIS DESIGN

Abstract

During strong ground motion, displacement controlled performance criterion does not considers the cumulative damage caused by cyclic load reversals, which basically depends on nonlinear performance of the structure. But, amount of hysteretic energy dissipation by the structure has a signature of cumulative damage. In this report, a constant ductility spectrum of cumulative damage measure has been proposed. To construct this spectrum, ductility demand has been taken a nonlinear performance parameter, and Park and Ang damage index has been taken as a cumulative damage measure. Using these demand spectra, an improved design methodology for earthquake resistant design of two dimensional reinforced concrete frames has been proposed where the damage due to plastic deformation can be distributed in the structure in a designed way