Performance-Based Seismic Design: Avant-Garde and Code-Compatible Approaches

Abstract

Current force-based codes for the seismic design of structures use design spectra and system-specific behavior factors to satisfy one or two predefined structural limit states . In contrast, performance-based seismic design aims to design a structure to fulfill any number of target performance objectives, defined as user-prescribed levels of structural response, loss, or casualties to be exceeded at a mean annual frequency less than a given maximum. First, a review of recent advances in probabilistic performance assessment is offered. Second, the salient characteristics of methodologies that have been proposed to solve the inverse problem of design are discussed. Finally, an alternative approach is proposed that relies on a new format for visualizing seismic performance, termed yield frequency spectra (YFS). YFS offer a unique view of the entire solution space for structural performance of a surrogate single-degree-of-freedom oscillator, incorporating uncertainty and propagating it to the output response to enable rapid determination of a good preliminary design that satisfies any number of performance objectives.