Multihazard Performance-Based Assessment Framework for Multistory Steel Buildings

Abstract

The paper proposes a uniform multihazard performance-based design framework for multistory steel buildings. Damage of structural and nonstructural components is associated with interstory drifts, residual drifts, and floor acceleration thresholds. Predefined measures that are meaningful to stakeholders, e.g., repair costs, are used to assess the performance of the building subjected to independent winds and earthquakes. The novelty of the procedure lies in: (1) developing a multihazard assessment methodology for buildings subjected to earthquake and wind, where both events are critical, (2) assessing the margin of safety for multi-story concentrically braced frame (CBF) buildings subjected to wind, using wind tunnel data for the simulation of case specific wind histories, and (3) evaluating the economic losses caused by multihazard damage, when allowing for controlled inelastic deformations of the CBF braces under wind excitations in moderate seismic regions. The implementation of response history analysis at the design level and beyond, combined with the probabilistic estimation of non-collapse losses, reduces significantly the conservatism in prescriptive wind design and promotes resilience under multihazard excitations.