Static Pushover Analysis Based on an Energy-Equivalent SDOF System: Application to Spatial Systems

In this paper a new enhanced Nonlinear Static Procedure (NSP) is presented and evaluated. The steps of the proposed methodology are quite similar to those of the well-known displacement modification method (ASCE 41-06). However, the determination of the characteristics of the equivalent single degree of freedom (E-SDOF) system is based on a different concept. Specifically, the E-SDOF system is determined by equating the external work of the lateral loads acting on the multi-degree of freedom (MDOF) system under consideration to the strain energy of the E-SDOF system. After a brief outline of the method, a series of applications to single storey R/C buildings is presented. Considering the results obtained by nonlinear time-history analysis as the reference solution, a comparison between the proposed and the conventional NSPs is conducted, which shows that the proposed method gives, in general, better results.