Kenneth W. Campbell

Independent Researcher · Model Development Group

Empirical ground-motion models are typically estimated via mixed-effects regression, to account for correlation between records from the same event or from the same site or station. Estimated values of the random effects are often used in further analyses, for example, to develop additional submodels or to investigate physical characteristics of in...

This article presents the development of ground-motion models (GMMs) of Fourier amplitude spectra for frequencies of 0.1–20 Hz and its potential extrapolation to 100 Hz at near-source distances using the effective amplitude spectrum (EAS) ordinates developed for the NGA-West2 project and the metadata and functional form from our previous NGA-West2...

It has become common in the development of ground-motion models (GMMs), especially using mixed-effects regression with crossed random effects, to calculate standard deviations, referred to as variance components, from sample statistics of the residuals (i.e. random effects and within-group errors) rather than using the variance components reported...

This article presents ground-motion models (GMMs) for inelastic response spectra using the NGA-West2 database. The inelastic response spectra are defined in terms of constant ductility. The GMMs are used to observe the effect of event scenarios, site conditions, and oscillator properties on maximum displacement. Using a large database enabled us to...

This article presents a suite of response spectrum (RS) and Fourier amplitude spectrum (FAS) site amplification models for Central and Eastern North America (CENA). The amplification database used in model development was produced through large-scale one-dimensional site response analyses and overcomes limitations of prior databases by providing br...

In this study, we derived a regionalized partially nonergodic empirical ground-motion model (GMM) for subduction interface and intraslab earthquakes using an extensive global database compiled as part of the NGA-Subduction project. The model can be used to estimate peak ground acceleration (PGA), peak ground velocity (PGV), and ordinates of 5%-damp...

We use a novel hybrid-scenario approach to develop a ground-motion model (GMM) for Housner’s spectrum intensity ( SI) using estimates of pseudo-spectral acceleration ( PSA) from the authors existing GMMs based on a scenario approach proposed in the literature and predictor variables from the same database used to develop the PSA GMMs. These estimat...

This report summarizes a comprehensive analysis of the damped inelastic response of a set of single-degree-of-freedom (SDOF) oscillators to a large number of ground motion recordings in the NGA-West2 database. We develop and present necessary tools to directly consider the effect of inelastic response in probabilistic seismic hazard analysis (PSHA)...

Many changes have been made to the design response spectrum used in the ASCE 7 Standard in recent years. One parameter that has not been investigated or revisited since its first appearance in FEMA 450-1/2003 is the long-period transition period parameter, T L. The long-period transition period parameter was introduced and defined as the corner per...

After publishing its original definition of cumulative absolute velocity ( CAV), the Electric Power Research Institute (EPRI) proposed a standardized version of CAV that it recommended is a better indicator of damage to structures of good design and construction than CAV. We refer to this intensity measure (IM) as CAV STD . EPRI proposed 0.16 g-s (...

In the course of developing ground-motion models (GMMs) of peak ground acceleration (PGA) for Japanese megathrust earthquakes, we discovered that empirical nonlinear site effects from these events are very different from those found for shallow crustal earthquakes in California and other global active tectonic regions. In particular, nonlinearity i...

In this article, ground-motion models (GMMs) for subduction earthquakes recently developed as part of the Next Generation Attenuation-Subduction (NGA-Sub) project are compared. The four models presented in this comparison study are documented in their respective articles submitted along with this article. Each of these four models is based on the a...

We used a ground-motion database of Japanese subduction interface (megathrust) earthquakes from the NGA-Subduction project to develop a series of ground-motion models (GMMs) for peak ground acceleration (PGA) that explore the effects of including random-effect event and station terms and differences in attenuation between forearc and backarc tecton...

This article summarizes the Next Generation Attenuation (NGA) Subduction (NGA-Sub) project, a major research program to develop a database and ground motion models (GMMs) for subduction regions. A comprehensive database of subduction earthquakes recorded worldwide was developed. The database includes a total of 214,020 individual records from 1,880...

This article develops global models of damping scaling factors (DSFs) for subduction zone earthquakes that are functions of the damping ratio, spectral period, earthquake magnitude, and distance. The Next Generation Attenuation for subduction earthquakes (NGA-Sub) project has developed the largest uniformly processed database of recorded ground mot...

The Next Generation Attenuation Relationships for Central & Eastern North-America (NGA-East) Geotechnical Working Group (GWG) has presented models for site amplification in Central and Eastern North America that represent a significant change from past practice, which was based on models developed for active tectonic regions. The GWG models are erg...

In this article, I propose a method for estimating the magnitude [Formula: see text] at which subduction megathrust earthquakes are expected to exhibit a break in magnitude scaling of both seismic source dimensions and earthquake ground motions. The methodology is demonstrated by applying it to 79 global subduction zones defined in the literature,...

Small-strain damping profiles developed from geotechnical laboratory testing have been observed to be smaller than the damping inferred from the observed site amplification from downhole array recordings. This study investigates the high-frequency spectral decay parameter ( 0 ) of earthquake motions from soil sites and evaluates the use of 0 to con...

This paper presents recommendation for nonlinear site amplification models in Central and Eastern North America (CENA), which are developed from one dimensional site response analyses results and accompanies linear site amplification model in companion paper. Two median nonlinear amplification models using identical functional forms are produced as...

We updated our NGA-West1 ground motion models (GMMs) for the horizontal components of Arias intensity (AI) and cumulative absolute velocity (CAV) using the functional form and Next Generation Attenuation (NGA)-West2 database we used to develop GMMs for peak-amplitude and peak-spectral ground motion intensity measures (GMIMs). Our results show that...

This paper presents the development of large scale simulation based data sets used to inform new site amplification models for Central and Eastern North America (CENA). Linear elastic, equivalent linear, and nonlinear one-dimensional (1D) site response simulations of site conditions in CENA are employed. An analysis tree is introduced to capture th...

Site amplification models for Central and Eastern North America (CENA) are developed from simulation results presented in a companion paper. Linear and nonlinear amplification functions are developed for response spectral (RS) accelerations and smoothed Fourier amplitude spectra (FAS). Linear RS model components include ground motion scaling with 3...

We present empirical linear site amplification models conditioned on time-averaged shear wave velocity in the upper 30 m (V S30 ) for central and eastern North America. The models are derived from ground motion data and site condition information from the NGA-East project and are intended for use with reference rock ground motion models. Site ampli...

The hybrid empirical method (HEM) of simulating ground motion intensity measures (GMIMs) in a target region uses stochastically simulated GMIMs in the host and target regions to develop adjustment factors that are applied to empirical GMIM predictions in the host region. In this study, the HEM approach was used to develop two new ground-motion pred...

This paper presents large scale simulation-based modelling of site amplification in two regions, Central and Eastern North America (CENA) and the Western Unites States (WUS). For CENA, a parametric study is developed with 1.2 million 1-D site response analyses (0.58 million of each linear elastic and nonlinear analyses) to represent the variability...

There is no scientific consensus on how finite virtual faults should be modeled in the probabilistic seismic hazard analysis of diffuse seismicity. Often pragmatic implementation decisions are made as a matter of convenience or computational efficiency. To better understand how differences in modeling virtual faults impact seismic hazard, we evalua...

In this study, we use a genetic algorithm to invert horizontal groundmotion intensity measures (GMIMs) predicted from the empirical Next Generation Attenuation-West2 (NGA-West2) ground-motion prediction equations (GMPEs) to estimate a consistent and correlated set of seismological parameters to use with an equivalent point-source stochastic model....

NGA-Subduction is a large multidisciplinary, multi-year research program to develop database resources and ground motion models (GMMs) for subduction-zone earthquakes. Coordinated by the Pacific Earthquake Engineering Research Center (PEER) and funded by FM Global, the project entails extensive technical interactions among many individuals and orga...

Time-averaged shear-wave velocity in the upper 30 m of a site (VS30) is the most common parameter used to characterize seismic site response in ground-motion models. However, in central and eastern North America (CENA), only 6% of the seismic recording stations that contributed data to the Next Generation Attenuation-East (NGA-East) project have me...

Adjustment factors are provided for converting ground-motion intensity measures between central and eastern North America (CENA) sites with different reference-rock site conditions (VS30 = 760, 2000, and 3000 m=s) for moment magnitudes ranging from 2 to 8, rupture distances ranging from 2 to 1200 km, Fourier amplitude spectra (FAS) for frequencies...

Campbell and Bozorgnia (2006) compared their newly developed Next Generation Attenuation-West1 project (NGA-West1) ground-motion prediction equation (GMPE) with a contemporary GMPE developed for the active crustal region of Europe and the Middle East. Based on that comparison, they proposed that their GMPE could be used to estimate ground motions i...

The spectral-decay parameter κ0 is often used to account for the reduction of the high-frequency amplitude of ground motion caused by attenuation within the site profile. In this study, we used the inverse random vibration theory approach described by Al Atiket al.(2014) to calculate Fourier amplitude spectra from predicted values of response-spect...

This study investigates the conditions for which one-dimensional (1D) nonlinear (NL) site response analysis results are distinct from equivalent-linear (EL) results and provides guidance for predicting when differences are large enough to be of practical significance. Relative differences in spectral accelerations and Fourier amplitudes computed fr...

We evaluate six crustal amplification models based on National Earthquake Hazards Reduction Program (NEHRP) B/C crustal profiles proposed for use in western North America (WNA) and often used in other active crustal regions where crustal properties are unknown. One of the models is based on an interpolation of generic rock velocity profiles previou...

We present a ground motion model (GMM) for the vertical-to-horizontal (V/H) ratios of peak ground acceleration, peak ground velocity, and 5%-damped pseudo-acceleration response spectra at periods ranging from 0.01 s to 10 s. The V/H GMM includes formulations for the median V/H ratio and for the aleatory within-event, between-event, and total standa...

We summarize the development of the NGA-West2 Bozorgnia-Campbell empirical ground motion model (GMM) for the vertical components of peak ground acceleration (PGA), peak ground velocity (PGV), and 5%-damped elastic pseudo-absolute acceleration response spectra (PSA) at vertical periods ranging from 0.01 s to 10 s. In the development of the vertical...

The time-averaged shear (S) wave velocity in the upper 30 meters of sediment (VS30) is a widely used site parameter for ground motion prediction. When unavailable from measurements, as is often the case at accelerograph stations in Central and Eastern North America (CENA), VS30 is typically estimated from proxies. We propose an alternative for CENA...

The NGA-West2 project is a large multidisciplinary, multi-year research program on the Next Generation Attenuation (NGA) models for shallow crustal earthquakes in active tectonic regions. The research project has been coordinated by the Pacific Earthquake Engineering Research Center (PEER), with extensive technical interactions among many individua...

A presentation of the model parameters and comparison of the median ground-motion values from the NGA-West2 GMPEs is presented for a suite of deterministic cases. In general, the median ground motions are similar, within a factor of about 1.5-2.0 for 5 < M < 7 and distances between 10-100 km Differences increase (on the order of 2-3) for large-magn...

This paper develops a new model for a Damping Scaling Factor (DSF) that can be used to adjust elastic response spectral ordinates for the vertical component of earthquake ground motion at a 5% viscous damping ratio to ordinates at damping ratios between 0.5 and 30%. Using the extensive NGA-West2 database of recorded ground motions from worldwide sh...

We used an expanded PEER NGA-West2 database to develop a new ground motion prediction equation (GMPE) for the average horizontal components of PGA, PGV, and 5% damped linear pseudo-absolute acceleration response spectra at 21 periods ranging from 0.01 s to 10 s. In addition to those terms included in our now superseded 2008 GMPE, we include a more-...

Ground motion prediction equations (GMPEs) for elastic response spectra are typically developed at a 5% viscous damping ratio. In reality, however, structural and nonstructural systems can have other damping ratios. This paper develops a new model for a damping scaling factor (DSF) that can be used to adjust the 5% damped spectral ordinates predict...

The reference rock site condition has two important applications for ground‐motion prediction in the stable continental region of central and eastern North America (CENA). (1) It represents the site condition for which ground motions are computed using semiempirical ground‐motion prediction equations. In addition, (2) it represents the site conditi...

Ground-motion models (GMMs) and ground-motion adjustment factors developed using the hybrid empirical method (HEM) are used in seismic-hazard analyses throughout the world as an alternative to GMMs developed from the more traditional empirical and simulation methods. The HEM uses the ratio of stochastic ground-motion simulations between a target an...

We used an expanded PEER NGA-West2 database of over 21,000 three-component recordings with moment magnitudes (M) ranging between 3.0 and 7.9 and distances ranging from 0 to 500 km to develop new ground motion prediction equations (GMPEs) for the average horizontal components of peak ground acceleration (PGA), peak ground velocity (PGV), and 5%-damp...

We developed an earthquake hazard model for Australia specifically for use in loss estimation, including industry and insured monetary losses caused by shaking and fire-following of industrial, commercial, and residential structures. The basis of our model is the 2012 hazard model developed by Geoscience Australia (GA) to update the Australia natio...

We used an expanded PEER NGA-West2 database to develop a new ground motion prediction equation (GMPE) for the average (RotD50) horizontal components of PGA, PGV, and 5%-damped linear pseudo-absolute acceleration response spectra at 21 periods ranging from 0.01 to 10 s. In addition to those terms included in our now superseded 2008 GMPE, we include...

Ground motion prediction equations (GMPEs) relate ground motion intensity measures to variables describing earthquake source, path, and site effects. From many available GMPEs, we select those models recommended for use in seismic hazard assessments in the Global Earthquake Model. We present a GMPE selection procedure that evaluates multidimensiona...

http://peer.berkeley.edu/publications/peer_reports/reports_2013/webPEER-2013-22-GEM.pdf

The M w 9.0 Tohoku-oki Japan earthquake produced approximately 2,000 ground motion recordings. We consider 1,238 three-component accelerograms corrected with component-specific low-cut filters. The recordings have rupture distances between 44 km and 1,000 km, time-averaged shear wave velocities of V S30 ¼ 90 m=s to 1,900 m/s, and usable response sp...

We provide a methodology that seamlessly integrates national seismic hazard models across the Canada-U.S. border to provide earthquake risk managers with updated and consistent seismic hazard science and technology in the two countries. Consistent with our U.S. hazard model, we developed a new Canadian model that incorporates (1) spatially varying...

: The project entitled Global Ground Motion Prediction Equations is funded by the Global Earthquake Model (GEM) Foundation and has the objective of recommending a harmonized suite of ground motion prediction equations (GMPEs) that can be used at the global and regional scales for seismic hazard analysis and loss estimation studies. As part of this...

: Ground-motion prediction equations (GMPEs) relate a ground-motion parameter (e.g. peak ground acceleration) to a set of explanatory variables describing the source, wave propagation path and site conditions. In the past five decades many hundreds of GMPEs for the prediction of PGA and linear elastic response spectral ordinates have been published...

Arias intensity (AI) and cumulative absolute velocity (CAV) have been proposed as instrumental intensity measures that can incorporate the cumulative effects of ground motion duration and intensity on the response of structural and geotechnical systems. In this study, we have developed a ground motion prediction equation (GMPE) for the horizontal c...

Cumulative absolute velocity (CAV) has been proposed as an instrumental index to quantify the potential earthquake damage to structures. We explore this idea further by developing a relationship between the standardized version of CAV and the Japan Meteorological Agency (JMA) and modified Mercalli (MMI) instrumental seismic intensities in order to...

The widespread application of the hybrid empirical method (HEM) has made it a viable approach for developing ground motion prediction equations (GMPEs) in regions where there are few strong motion recordings but ample weak motion data from small-to-moderate magnitude earthquakes. The HEM uses empirical estimates of ground motion in a host region to...

The 2009 NEHRP Provisions modified the definition of horizontal ground motion from the geometric mean of spectral accelerations for two components to the peak response of a single lumped mass oscillator regardless of direction. These maximum-direction (MD) ground motions operate under the assumption that the dynamic properties of the structure (e.g...

The U.S. Nuclear Regulatory Commission (USNRC) uses the standardized version of the cumulative absolute velocity (CAV) together with the response spectra of the recorded ground motion at a site to determine whether a nuclear power plant must be shut down for inspection after an earthquake. In order to better understand the impact of these criteria...

The JMA (Japan Meteorological Agency) seismic intensity scale has been used in Japan as a measure of earthquake ground shaking effects since 1949. It has traditionally been assessed after an earthquake based on the judgment of JMA officials. In 1996 the scale was revised as an instrumental seismic intensity measure (IJMA) that could be used to rapi...

Cumulative absolute velocity (CAV), defined as the integral of the absolute acceleration time series, has been used as an index to indicate the possible onset of structural damage to nuclear power plant facilities and liquefaction of saturated soils. However, there are very few available ground motion prediction equations for this intensity measure...

We determined the stress parameter, Delta sigma, for the eight earthquakes studied by Atkinson and Boore (2006), using an updated dataset and a revised point-source stochastic model that captures the effect of a finite fault. We consider four geometrical-spreading functions, ranging from 1/R at all distances to two- or three-part functions. The Del...

This paper presents deterministic and probabilistic predictions of inelastic response spectra based on a comprehensive ground motion prediction equation (GMPE). Our analysis reveals that over a wide structural period range, the magnitude scaling for an inelastic system is higher than that for an elastic system, especially for ductility levels great...

This paper presents the process and fundamental results of a comprehensive ground motion prediction equation (GMPE, or "attenuation" relationship) developed for inelastic response spectra. We used over 3,100 horizontal ground motions recorded in 64 earthquakes with moment magnitudes ranging from 4.3-7.9 and rupture distances ranging from 0.1-199 km...

This paper presents the results of a comprehensive ground motion prediction equation (GMPE, or "attenuation" relationship) developed for inelastic response spectra. Inelastic spectra for over 3100 horizontal ground motions recorded in 64 worldwide earthquakes are used to develop the GMPE, which is used in both deterministic and probabilistic hazard...

Why do stochastic point-source and finite-fault simulation models not agree on the predicted ground motions for moderate earthquakes at large distances? This question was posed by Ken Campbell, who attempted to reproduce the Atkinson and Boore (2006) ground-motion prediction equations for eastern North America using the stochastic point-source prog...

Measured and calculated values of the effective quality factor Q ef and the site attenuation parameter κ 0 for unconsolidated and semiconsolidated sediments in eastern North America (ENA) indicate that the latter is strongly dependent on sediment thickness. Estimates of κ 0 for National Earthquake Hazard Reduction Program (NEHRP) BC site profiles (...

Tavakoli and Pezeshk (2005) conclude that the use of a point-source single-corner source spectrum by Campbell (2003, 2004) causes his eastern North America (ENA) hybrid empirical ground-motion model to underestimate ground-motion amplitudes from near-source large-magnitude earthquakes. This conclusion was based on published studies that found that...