Ground motion selection for simulation-based seismic hazard and structural reliability assessment

ABSTRACT The use of numerical simulations in probabilistic seismic hazard analysis (PSHA) has achieved a promising level of reliability in recent years. One example is the CyberShake project, which incorporates physics-based 3D ground-motion simulations within seismic hazard calculations. Nonetheless, considerable computational time and resources are required due to the significant processing requirements imposed by source-based models on one hand, and the large number of seismic sources and possible rupture variations on the other. This article proposes to use a less computationally demanding simulation-based PSHA framework for CyberShake. The framework can accurately represent the seismic hazard at a site, by only considering a subset of all the possible earthquake scenarios, based on a Monte-Carlo simulation procedure that generates earthquake catalogs having a specified duration. In this case, ground motions need only be simulated for the scenarios selected in the earthquake catalog, and hazard calculations are limited to this subset of scenarios. To validate the method and evaluate its accuracy in the CyberShake platform, the proposed framework is applied to three sites in southern California, and hazard calculations are performed for earthquake catalogs with different lengths. The resulting hazard curves are then benchmarked against those obtained by considering the entire set of earthquake scenarios and simulations, as done in CyberShake. Both approaches yield similar estimates of the hazard curves for elastic pseudospectral accelerations and inelastic demands, with errors that depend on the length of the Monte-Carlo catalog. With 200,000 yr catalogs, the errors are consistently smaller than 5% at the 2% probability of exceedance in 50 yr hazard level, using only ∼3% of the entire set of simulations. Both approaches also produce similar disaggregation patterns. The results demonstrate the potential of the proposed approach in a simulation-based PSHA platform like CyberShake and as a ground-motion selection tool for seismic demand analyses.

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An enhanced sequential ground motion selection for risk assessment using a Bayesian updating approach

Journal of Building Engineering ◽

10.1016/j.jobe.2021.103745 ◽

2021 ◽

pp. 103745

Author(s):

Shima Taheri ◽

R. Karami Mohammadi

Keyword(s):

Risk Assessment ◽

Ground Motion ◽

Bayesian Updating ◽

Ground Motion Selection ◽

Selection For

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Multivariate return period‐based ground motion selection for improved hazard consistency over a vector of intensity measures

Earthquake Engineering & Structural Dynamics ◽

10.1002/eqe.3338 ◽

2020 ◽

Author(s):

Ao Du ◽

Jamie E. Padgett

Keyword(s):

Ground Motion ◽

Return Period ◽

Intensity Measures ◽

Ground Motion Selection ◽

Selection For

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Consideration and Propagation of Ground Motion Selection Epistemic Uncertainties to Seismic Performance Metrics

Earthquake Spectra ◽

10.1193/061317eqs114m ◽

2018 ◽

Vol 34 (2) ◽

pp. 587-610 ◽

Cited By ~ 6

Author(s):

Karim Tarbali ◽

Brendon A. Bradley ◽

Jack W. Baker

Keyword(s):

Seismic Hazard ◽

Seismic Response ◽

Ground Motion ◽

Seismic Performance ◽

Performance Metrics ◽

Epistemic Uncertainty ◽

Seismic Demand ◽

Intensity Measures ◽

Ground Motion Selection ◽

The Mean

This paper investigates various approaches to propagate the effect of epistemic uncertainty in seismic hazard and ground motion selection to seismic performance metrics. Specifically, three approaches with different levels of rigor are presented for establishing the conditional distribution of intensity measures considered for ground motion selection, selecting ground motion ensembles, and performing nonlinear response history analyses (RHAs) to probabilistically characterize seismic response. The mean and distribution of the seismic demand hazard is used as the principal means to compare the various results. An example application illustrates that, for seismic demand levels significantly below the collapse limit, epistemic uncertainty in seismic response resulting from ground motion selection can generally be considered as small relative to the uncertainty in the seismic hazard itself. In contrast, uncertainty resulting from ground motion selection appreciably increases the uncertainty in the seismic demand hazard for near-collapse demand levels.

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Ground motion selection for seismic slope displacement analysis using a generalized intensity measure distribution method

Earthquake Engineering & Structural Dynamics ◽

10.1002/eqe.2998 ◽

2017 ◽

Vol 47 (5) ◽

pp. 1352-1359 ◽

Cited By ~ 8

Author(s):

Wenqi Du ◽

Gang Wang

Keyword(s):

Ground Motion ◽

Intensity Measure ◽

Distribution Method ◽

Displacement Analysis ◽

Ground Motion Selection ◽

Selection For ◽

Slope Displacement ◽

Measure Distribution

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Ground Motion Selection in the Near-Fault Region considering Directivity-Induced Pulse Effects

Earthquake Spectra ◽

10.1193/102517eqs223m ◽

2019 ◽

Vol 35 (2) ◽

pp. 759-786 ◽

Cited By ~ 9

Author(s):

Karim Tarbali ◽

Brendon A. Bradley ◽

Jack W. Baker

Keyword(s):

Seismic Hazard ◽

Ground Motion ◽

Hazard Analysis ◽

Ground Motions ◽

Seismic Hazard Analysis ◽

Response Analysis ◽

Seismic Demand ◽

Ground Motion Selection ◽

Near Fault ◽

Fault Region

This paper focuses on the selection of ground motions for seismic response analysis in the near-fault region, where directivity effects are significant. An approach is presented to consider forward directivity velocity pulse effects in seismic hazard analysis without separate hazard calculations for ‘pulse-like’ and ‘non-pulse-like’ ground motions, resulting in a single target hazard (at the site of interest) for ground motion selection. The ability of ground motion selection methods to appropriately select records that exhibit pulse-like ground motions in the near-fault region is then examined. Applications for scenario and probabilistic seismic hazard analysis cases are examined through the computation of conditional seismic demand distributions and the seismic demand hazard. It is shown that ground motion selection based on an appropriate set of intensity measures (IMs) will lead to ground motion ensembles with an appropriate representation of the directivity-included target hazard in terms of IMs, which are themselves affected by directivity pulse effects. This alleviates the need to specify the proportion of pulse-like motions and their pulse periods a priori as strict criteria for ground motion selection.

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