Static Versus Dynamic Methods of Analysis for Estimating Seismic Performance

Abstract

Nonlinear static methods are evaluated and compared with nonlinear dynamic methods for estimating the seismic performance of structures. Emphasis is given on assessing the applicability of nonlinear static methods for RC buildings, and on comparing the building’s capacity obtained using nonlinear static and nonlinear response history analysis. The first task refers to the ability of alternative static pushover-based methods to estimate the response at the level of a member or of a story. Plain as well as more elaborate pushover methods such as the Modal Pushover Analysis method and the Consecutive Modal Pushover method are included in our evaluation. The second task refers to the qualitative comparison at the global level between static pushover and nonlinear response history analysis when either the static pushover or the Incremental Dynamic Analysis (IDA) setting is adopted. When the static pushover setting is adopted, we show that nonlinear static methods can be compared with the IDA curve when the base shear instead of spectral acceleration is plotted on the ordinates, while the dispersion among the single-record IDAs is considerably reduced. Alternatively, the comparison can be performed within the IDA setting if appropriate R-C 1-T relationships, simplified or more advanced (e.g. SPO2IDA), are adopted. Each setting shows different qualitative characteristics of the two seismic performance estimation approaches and has different practical applications.