NGA-West2 Database

2014 ◽  
Vol 30 (3) ◽  
pp. 989-1005 ◽  
Author(s):  
Timothy D. Ancheta ◽  
Robert B. Darragh ◽  
Jonathan P. Stewart ◽  
Emel Seyhan ◽  
Walter J. Silva ◽  
...  
Keyword(s):  
Ground Motion ◽  
Ground Motions ◽  
Prediction Equation ◽  
Ground Motion Prediction ◽  
Motion Data ◽  
Crustal Earthquakes ◽  
Active Tectonic ◽  
Quality Checks ◽  
Working Groups ◽  
Moderate Magnitude

The NGA-West2 project database expands on its predecessor to include worldwide ground motion data recorded from shallow crustal earthquakes in active tectonic regimes post-2000 and a set of small-to-moderate-magnitude earthquakes in California between 1998 and 2011. The database includes 21,336 (mostly) three-component records from 599 events. The parameter space covered by the database is M 3.0 to M 7.9, closest distance of 0.05 to 1,533 km, and site time-averaged shear-wave velocity in the top 30 m of V S30 = 94 m/s to 2,100 m/s (although data becomes sparse for distances >400 km and V S30 > 1,200 m/s or <150 m/s). The database includes uniformly processed time series and response spectral ordinates for 111 periods ranging from 0.01 s to 20 s at 11 damping ratios. Ground motions and metadata for source, path, and site conditions were subject to quality checks by ground motion prediction equation developers and topical working groups.

Ground motion prediction equations for significant duration using the KiK-net database

2020 ◽  
pp. 875529302097097
Author(s):  
Mahdi Bahrampouri ◽  
Adrian Rodriguez-Marek ◽  
Russell A Green
Keyword(s):  
Ground Motion ◽  
Structural Engineering ◽  
Ground Motions ◽  
Motion Prediction ◽  
Ground Motion Prediction ◽  
Subduction Earthquakes ◽  
Significant Duration ◽  
Crustal Earthquakes ◽  
Active Tectonic ◽  
The Difference

Significant duration of strong shaking quantifies the length of time during which strong earthquake-induced shaking occurs at a given site. Significant duration has multiple applications in Geotechnical and Structural Engineering. However, while multiple ground motion prediction (GMPE) equations for duration exist for shallow crustal tectonic environments, at the time of this publication, there are few published models for predicting significant duration of subduction earthquakes. To address this need and to identify the difference between significant duration of motions resulting from earthquakes in different tectonic regimes, we develop predictive equations for significant duration applicable to interface and intraslab subduction earthquakes and shallow crustal earthquakes in active tectonic regimes using the KiK-net ground motion database. The GMPEs are applicable to earthquakes with M4 to 9. In addition, the influence of earthquake magnitude on duration due to path effects is captured in the proposed relationships. Based on the relationships proposed in this study, we note that the duration of ground motions from subduction earthquakes is longer than those of shallow crustal earthquakes that have similar magnitudes and distances. The predictions of duration for shallow crustal earthquakes in active tectonic regimes developed in this study are consistent with those from previous studies.

scholarly journals A New Approach to Estimate a Mixed Model–Based Ground Motion Prediction Equation

2007 ◽  
Vol 23 (3) ◽  
pp. 665-684 ◽  
Author(s):  
Behrooz Tavakoli ◽  
Shahram Pezeshk
Keyword(s):  
Ground Motion ◽  
Mixed Model ◽  
Prediction Equation ◽  
Regression Coefficients ◽  
Motion Prediction ◽  
Ground Motion Prediction Equation ◽  
Predictive Equation ◽  
Ground Motion Prediction ◽  
Data Set ◽  
Motion Data

A derivative-free approach based on a hybrid genetic algorithm (HGA) is proposed to estimate a mixed model–based ground motion prediction equation (attenuation relationship) with several variance components. First, a simplex search algorithm (SSA) is used to reduce the search domain to improve the convergence speed. Then, a genetic algorithm (GA) is employed to obtain the regression coefficients and the uncertainties of a predictive equation in a unified framework using one-stage maximum-likelihood estimation. The proposed HGA results in a predictive equation that best fits a given ground motion data set. The proposed HGA is able to handle changes in the functional form of the equation. To demonstrate the solution quality of the proposed HGA, the regression coefficients and the uncertainties of a test function based on a simulated ground motion data set are obtained. Then, the proposed HGA is applied to fit two functional attenuation forms to an actual data set of ground motion. For illustration, the results of the HGA are compared with those used by previous conventional methods. The results indicate that the HGA is an appropriate algorithm to overcome the shortcomings of the previous methods and to provide reliable and stable solutions.

Ground-Motion Attenuation Model for Small-To-Moderate Shallow Crustal Earthquakes in California and Its Implications on Regionalization of Ground-Motion Prediction Models

2010 ◽  
Vol 26 (4) ◽  
pp. 907-926 ◽  
Author(s):  
Brian Chiou ◽  
Robert Youngs ◽  
Norman Abrahamson ◽  
Kofi Addo
Keyword(s):  
Ground Motion ◽  
Regional Differences ◽  
Regional Difference ◽  
Prediction Models ◽  
Motion Prediction ◽  
Ground Motion Prediction ◽  
Small Magnitude ◽  
Attenuation Model ◽  
Crustal Earthquakes ◽  
Active Tectonic

This paper presents the development of a ground-motion prediction model for small-to-moderate shallow crustal earthquakes (3M5.5, up to 200 km distance) using data from the California ShakeMap systems. Our goal is to provide an empirical model that can be confidently used in the investigation of ground-motion difference between California and other active tectonic regions (such as the Pacific Northwest and British Columbia, Canada) where the bulk of ground-motion data from shallow crustal earthquakes is in the small-to-moderate magnitude range. This attenuation model is developed as a small-magnitude extension of the Chiou and Youngs NGA model (CY2008). We observe, and incorporate into this model, a regional difference in median amplitude between central and southern California earthquakes. The strength of the regional difference diminishes with increasing spectral period. More importantly, it is magnitude dependent and becomes insignificant for M6 earthquakes, as indicated by the large-magnitude California data used in CY2008. Together, these findings have important implications on the practice of utilizing the regional differences observed in small-to-moderate earthquakes to infer the regional differences expected in large earthquakes, including the NGA model applicability in active tectonic regions outside California.

Empirical Terrain-Based Topographic Modification Factors for Use in Ground Motion Prediction

2017 ◽  
Vol 33 (1) ◽  
pp. 157-177 ◽  
Author(s):  
Manisha Rai ◽  
Adrian Rodriguez-Marek ◽  
Brian S. Chiou
Keyword(s):  
Ground Motion ◽  
Ground Motions ◽  
Prediction Equation ◽  
Motion Prediction ◽  
Topographic Effects ◽  
Ground Motion Prediction ◽  
Modeling Error ◽  
Data Set ◽  
A Site ◽  
The Relationship

We develop a model to predict topographic effects on ground motions using the NGA-West2 data set. Topography at a site is quantified using three parameters: smoothed curvature, smoothed slope, and relative elevation. We examine the relationship between the site residuals, which represent the average modeling error of the reference ground motion prediction equation at a station, and the three topographic parameters. Our analysis shows that there are statistically significant trends in site residuals with respect to relative elevation and smoothed curvature. We propose modification factors to the Chiou and Youngs (2014) model that account for topographic effects on both the median and the standard deviation. These factors are period dependent and are a function of the relative elevation at the site. The factors result in amplification on median by a factor as high as 1.13 at T = 0.5 s for higher values of relative elevation, and deamplification as low as 0.75 between T = 2 s to 3 s for lower values of relative elevations.

Ground motion prediction equation for crustal earthquakes in Taiwan

2020 ◽  
Vol 36 (4) ◽  
pp. 2129-2164
Author(s):  
Van-Bang Phung ◽  
Chin Hsiung Loh ◽  
Shu Hsien Chao ◽  
Brian SJ Chiou ◽  
Bor-Shouh Huang
Keyword(s):  
Seismic Hazard ◽  
Ground Motion ◽  
Functional Form ◽  
Hazard Analysis ◽  
Prediction Equation ◽  
Motion Prediction ◽  
Ground Motion Prediction Equation ◽  
Ground Motion Prediction ◽  
Crustal Earthquakes ◽  
Magnitude Scaling

We develop a ground motion prediction equation (GMPE) for estimating horizontal ground motion amplitudes caused by crustal earthquakes, based on an integrated data set that includes strong motion recordings mainly from Taiwan earthquakes and only from large magnitude earthquakes in the NGA-West2 database. This GMPE is developed for probabilistic seismic hazard analysis study, which is introduced as a part of Taiwan Senior Seismic Hazard Analysis Committee Level 3 projects. The functional form developed by Chiou and Youngs was carefully studied to determine the key modeling parameters needed to regress against ground motion in the target region. Using this functional form, the GMPE achieves considerable improvement over previously developed Taiwan GMPEs. In particular, the use of a high-order function in magnitude scaling enables representation of the saturation effects of large earthquakes. Moreover, consideration of focal mechanisms, depth effects, and dip effects are used to correct the magnitude scaling; consideration of nonlinear site amplification is conditioned on VS30 and reference ground motion on rock; and consideration of basin depth effect is a function of Z1.0 in correlation with VS30. In addition, ground motion data used in this study are not only expanded by more than three times as many earthquakes and records compared with a previous Taiwan model but also provide the metadata of these records that were not available or were previously incomplete. In this study, we compare the proposed model with the NGA-West2 models and discuss the regional difference in ground motion in terms of spectral shape, magnitude scaling, distance scaling, depth scaling, style of faulting, and site effects. We provide median and single standard deviations of peak ground acceleration and 5% damped pseudospectral acceleration response ordinates of the orientation-independent average horizontal component of ground motion (RotD50) for the spectral period of 0.01–10 s.

scholarly journals Empirical Spectral Amplification Function for a Reference Site Near Keddara Dam in Algeria using Strong Motion Data.

2021 ◽  
Author(s):  
Faouzi Gherboudj ◽  
Toufiq Ouzandja ◽  
Rabah Bensalem
Keyword(s):  
Ground Motion ◽  
Reference Site ◽  
Ground Motions ◽  
Free Field ◽  
Strong Motion ◽  
Ambient Vibration ◽  
Motion Prediction ◽  
Ground Motion Prediction ◽  
Strong Motion Data ◽  
Motion Data

Abstract This paper deals with empirical spectral amplification function for a reference site (STK) near Keddara dam in Algeria using local strong ground motion of earthquakes of magnitudes Mw 4.0-6.8. Amplification function is obtained as the 5% damped mean spectral ratio of surface observed and the rock predicted ground motions and it is compared to the ambient vibration HVSR which shows a good agreement in terms of fundamental frequency and curve tendency. In addition, recorded ground motions are compared to surface predicted motion with modified GMPE, the site term of the local ground motion prediction equation is adjusted based on the obtained amplification function of the free field STK site. Examples of the M 6.8, M5.4 and M4.7 earthquakes show clearly the advantage of using the adjusted Ground Motion Prediction Equations (GMPE) for predicting surface ground motion. Site effect characterization and the adjusted GMPE presented in this study provide the basis elements toward partially non ergodic site specific-Probabilistic seismic hazard assessment (PSHA) application based on local strong motion data in Algeria.

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