Nonstationary Stochastic Simulation of Strong Ground Motion Time Histories Including Natural Variability: Application to the K-Net Japanese Database

Recent developments in performance-based analyses and the high performance of computational facilities have led to an increased trend for utilizing nonlinear time-history analysis in seismic evaluation of the performance of structures. One of the crucial issues of such analysis is the selection of appropriate acceleration time histories set that satisfy design code requirements at a specific site. In literature, there are three sources of acceleration time histories: 1) recorded accelerograms in real earthquakes scaled to match design code spectrum/uniform hazard spectra/conditional mean spectrum, 2) artificial records generated from white noise spectra to satisfy design code spectrum, and 3) synthetic records obtained from seismological models. Due to the increase of available strong ground motion database, using and scaling real recorded accelerograms is becoming one of the most contemporary research issues in this field. In this study, basic methodologies and criteria for selecting strong ground motion time histories are discussed. Design code requirements for scaling are summarized for ASCE/SEI-7-10, EC8 and Turkish Seismic Codes. Examples for scaling earthquake records to uniform hazard spectra are provided.

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Suitability of Synthesized Waveforms for Seismic Qualification of Equipment

Journal of Pressure Vessel Technology ◽

10.1115/1.3264310 ◽

1984 ◽

Vol 106 (1) ◽

pp. 63-68 ◽

Cited By ~ 2

Author(s):

D. D. Kana ◽

D. J. Pomerening

Keyword(s):

Ground Motion ◽

Strong Ground Motion ◽

Ground Level ◽

Frequency Content ◽

Gaussian Random Process ◽

Earthquake Excitation ◽

Acceleration Time Histories ◽

Time Histories ◽

Orthogonal Components ◽

Strong Ground

Qualification of nuclear plant equipment and components can be performed by analysis, test, or a combination of both. It is often required to synthesize artificial time histories which represent earthquake excitation at either ground level, or some elevated level of a structure. A set of parameters appropriate for the synthesis of acceleration time histories is developed. The parameters are based on a study of six typical earthquake accelerograms, and include general characteristics of the motion, a definition of strong ground motion, frequency content, stationarity, coherence between orthogonal components, and amplitude probability density. It is concluded that the strong ground motion can be approximated by a stationary Gaussian random process, whose frequency content depends on the ground or elevated position of concern. Coherence between orthogonal components is low at ground level, but can become high at elevated structural levels due to coupled responses. Some examples are given for application of the parameters to qualification by testing, as a means of achieving better satisfaction of existing criteria.

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Predicting Probabilistic-Based Strong Ground Motion Time Series for Citadel of Arg-E-Bam (South-East of Iran)

Journal of Earthquake Engineering ◽

10.1080/13632460802597976 ◽

2009 ◽

Vol 13 (4) ◽

pp. 482-499 ◽

Cited By ~ 7

Author(s):

A. Nicknam ◽

A. Yazdani ◽

S. Yaghmaei Sabegh

Keyword(s):

Time Series ◽

Ground Motion ◽

Strong Ground Motion ◽

Motion Time ◽

East Of Iran ◽

Strong Ground

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Study on Long-Period Inelastic Spectra of Strong Ground Motion Containing Velocity Pulse

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.3919 ◽

2011 ◽

Vol 243-249 ◽

pp. 3919-3926 ◽

Cited By ~ 2

Author(s):

Chun Feng Li ◽

Xiao Jun Li ◽

Yian Xiang Yu ◽

Yong Bo Li

Keyword(s):

Ground Motion ◽

Strong Ground Motion ◽

Time History ◽

Elastic Response ◽

Velocity Pulse ◽

Long Period ◽

Elastic Response Spectra ◽

Time Histories ◽

Original Time ◽

Strong Ground

In order to understand fully the effect of strong ground motion containing velocity pulse on constant-ductility long-period inelastic spectra, we synthesize two time histories, not containing velocity pulse, whose elastic spectra are identical to that of original time history containing velocity pulse, and whose peak accelerations are as big as that of the original time history. The reason why we synthesize two time histories for one original time history is to avoid the effect of randomicity in selecting sample. We select two time histories of 1999 CHi-CHi earthquake as original time histories, one of which has two synthesized counterparts. It is found that although the elastic response spectra of original time histories are identical with those of their synthesized counterparts, their constant-ductility long-period inelastic spectra are different. We consider that the difference results from the velocity pulses which exist in the original time histories.

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Shaking is Almost Always a Surprise: The Earthquakes That Produce Significant Ground Motion

Seismological Research Letters ◽

10.1785/0220200165 ◽

2020 ◽

Vol 92 (1) ◽

pp. 460-468

Author(s):

Sarah E. Minson ◽

Annemarie S. Baltay ◽

Elizabeth S. Cochran ◽

Sara K. McBride ◽

Kevin R. Milner

Keyword(s):

Ground Motion ◽

Strong Ground Motion ◽

Natural Variability ◽

Significant Source ◽

Relative Impact ◽

Frequency Relationship ◽

Large Earthquakes ◽

Strong Ground

Abstract Although small earthquakes are expected to produce weak shaking, ground motion is highly variable and there are outlier earthquakes that generate more shaking than expected—sometimes significantly more. We explore datasets of M 0.5–8.3 earthquakes to determine the relative impact of frequent, smaller-magnitude earthquakes that rarely produce strong ground motion, to rare, large earthquakes that always cause strong shaking. We find that the natural variability of ground motion, combined with the Gutenberg–Richter magnitude–frequency relationship, ensures that most occurrences of any ground motion come from earthquakes of smaller magnitude than expected, often >2 magnitude units smaller. This holds even for very strong shaking (>20%g), suggesting that M<7 earthquakes could be a significant source of damage.

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