This paper examines four methods by which ground motions can be selected for dynamic seismic response analyses of engineered systems when the underlying seismic hazard is quantified via ground motion simulation rather than empirical ground motion prediction equations. Even with simulation-based seismic hazard, a ground motion selection process is still required in order to extract a small number of time series from the much larger set developed as part of the hazard calculation. Four specific methods are presented for ground motion selection from simulation-based seismic hazard analyses, and pros and cons of each are discussed via a simple and reproducible illustrative example. One of the four methods (method 1 'direct analysis') provides a 'benchmark' result (i.e. using all simulated ground motions), enabling the consistency of the other three more efficient selection methods to be addressed. Method 2 ('stratified sampling') is a relatively simple way to achieve a significant reduction in the number of ground motions required through selecting subsets of ground motions binned based on an intensity measure, IM. Method 3 ('simple multiple stripes') has the benefit of being consistent with conventional seismic assessment practice using as-recorded ground motions, but both methods 2 and 3 are strongly dependent on the efficiency of the conditioning IM to predict the seismic responses of interest. Method 4 ('GCIM-based selection') is consistent with 'advanced' selection methods used for as-recorded ground motions, and selects subsets of ground motions based on multiple IMs, thus overcoming this limitation in methods 2 and 3.

We propose a list of simple parameters that act as proxies for the response of more complicated engineered systems and therefore can be studied to validate new methods of ground-motion simulation for engineering applications. The primary list of parameters includes correlation of spectral acceleration across periods, ratio of maximum-to-median spectral acceleration across all horizontal orientations, and the ratio of inelastic-to-elastic displacement, all of which have reliable empirical models against which simulations can be compared. We also describe several secondary parameters, such as directivity pulse period and structural collapse capacity, that do not have robust empirical models but are important for engineering analysis. We then demonstrate the application of these parameters to exemplify simulations computed using a variety of methods, including stochastic finite fault, Graves-Pitarka hybrid broadband, and a composite source model. In general, each simulation method matches empirical models for some parameters and not others, indicating that all relevant parameters need to be carefully validated. Online Material: Tables of ground-motion records and simulations selected to have comparable response spectra, and MATLAB code to compute simple proxies for the response of engineering systems.

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Chapter 16 of ASCE 7 governs the selection of ground motions for analysis of new buildings and requires recordings that meet specified criteria. If a sufficient number of recordings cannot be found, it allows the use of “appropriate simulated ground motions,” but does not provide further guidance. This paper outlines a procedure for generating and selecting a set of “appropriate” hybrid broadband simulations and a comparable set of recordings. Both ground motion sets are used to analyze a building in Berkeley, California, and the predicted structural performance is compared. The structural behavior resulting from recordings and simulations is similar, and most discrepancies are explained by differences in directional properties such as orientation of the maximum spectral response. These results suggest that when simulations meet the criteria outlined for recordings in ASCE 7 and properties such as directionality are realistically represented, simulations provide useful results for structural analysis and design.