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USGS · 70035846

Scaling earthquake ground motions for performance-based assessment of buildings

Y.-N. Huang·A.S. Whittaker·N. Luco·R.O. Hamburger
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Abstract

The impact of alternate ground-motion scaling procedures on the distribution of displacement responses in simplified structural systems is investigated. Recommendations are provided for selecting and scaling ground motions for performance-based assessment of buildings. Four scaling methods are studied, namely, (1) geometric-mean scaling of pairs of ground motions, (2) spectrum matching of ground motions, (3) first-mode-period scaling to a target spectral acceleration, and (4) scaling of ground motions per the distribution of spectral demands. Data were developed by nonlinear response-history analysis of a large family of nonlinear single degree-of-freedom (SDOF) oscillators that could represent fixed-base and base-isolated structures. The advantages and disadvantages of each scaling method are discussed. The relationship between spectral shape and a ground-motion randomness parameter, ε, is presented. A scaling procedure that explicitly considers spectral shape is proposed.

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Y.-N. Huang, A.S. Whittaker, N. Luco, R.O. Hamburger. 2011. Scaling earthquake ground motions for performance-based assessment of buildings. https://doi.org/10.1061/(asce)st.1943-541x.0000155

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