PEER Reports

PEER Reports

Seismic Evaluation and Retrofit of Existing Tall Buildings in California: Case Study of a 35-Story Steel Moment-Resisting Frame Building in San Francisco, PEER Report 2015-14

Jiun-Wei Lai
Shanshan Wang
Matthew J. Schoettler
Stephen A. Mahin
2015

The seismic performance of new tall buildings located in regions of high seismic hazard has been recently investigated by Pacific Earthquake Engineering Research Center (PEER) under its Tall Buildings Initiative (TBI) program. This program has now expanded to assess the seismic performance of existing tall buildings. Buildings being considered are 20 stories or more in height and were constructed on the west coast of the U.S. between about 1960 and 1990. During that period, several hundred tall buildings were constructed in California, but earthquake-resistant design procedures were not as...

A Methodology for the Estimation of Kappa (k) from Large Datasets: Example Application to Rock sites in the NGA-East Database and Implications on Design Motions, PEER Report 2016-01

Olga-Joan Ktenidou
Norman A. Abrahamson
Robert B. Darragh
Walter J. Silva
2016

This report reviews four of the main approaches (two band-limited and two broadband) currently used for estimating the site κ0 : the acceleration slope (AS) above the corner frequency, the displacement slope (DS) below the corner frequency, the broadband (BB) fit of the spectrum, and the response spectral shape (RESP) template. Using these four methods, estimates of κ0 for rock sites in Central Eastern North America (CENA) in the shallow crustal dataset from NGA- East are computed for distances less than 100 km.

Using all of the data within 100 km, the mean κ0...

Semi-Automated Procedure for Windowing Time Series and Computing Fourier Amplitude Spectra for the NGA-West2 Database, PEER Report 2016-02

Tadahiro Kishida
Olga-Joan Ktenidou
Robert B. Darragh
Walter J. Silva
2016

This document introduces and describes the data processing methods developed for computing Fourier amplitude spectra (FAS) in the NGA-West2 project. The products of this study can be used to estimate high-frequency attenuation, kappa (κ), to estimate site amplification through empirical spectral ratios, as well as to aid in the development of ground-motion models (GMMs) based on FAS. To accommodate different potential user objectives, we selected five time windows in the acceleration time series (noise, P-wave, S-wave, coda, and the entire record) for which we compute the FAS. The...

Ground-Motion Prediction Equations for Arias Intensity Consistent with the NGA-West2 Ground-Motion Models, PEER Report 2016-05

Charlotte Abrahamson
Hao-Jun Michael Shi
Brian Yang
2016

Following the approach outlined in the Watson-Lamprey and Abrahamson [2006] conditional model for Arias intensity, we use the NGA-West2 database to derive a new scaling model for Arias intensity given peak ground acceleration (PGA), T = 1 sec spectral acceleration (SAT1), shear-wave velocity in the top 30 m (VS30), and magnitude. By combining this conditional model with each of five NGA-West2 ground-motion models for PGA and SAT1, we derived five new ground motion prediction equations (GMPEs) for the median and standard deviation...

Resilience of Critical Structures, Infrastructure, and Communities, PEER Report 2016-08

Gian Paolo Cimellaro
Ali Zamani Noori
Omar Kammouh
2016

In recent years, the concept of resilience has been introduced to the field of engineering as it relates to disaster mitigation and management. However, the built environment is only one element that supports community functionality. Maintaining community functionality during and after a disaster, defined as resilience, is influenced by multiple components. This report summarizes the research activities of the first two years of an ongoing collaboration between the Politecnico di Torino and the University of California, Berkeley, in the field of disaster resilience.

Chapter 1...

Recommendations for Ergodic Nonlinear Site Amplification in Central and Eastern North America, PEER Report 2017-05

Youssef M.A. Hashash
Joseph A. Harmon
Okan Ilhan
Grace A. Parker
Jonathan P. Stewart
2017

This document is a companion report to Expert Panel Recommendation for Ergodic Linear Site Amplification Models in central and eastern North America (PEER Report 2017/04 , Stewart et al. 2017). This report describes the panel recommendations for ergodic median nonlinear site amplification models, which are meant to accompany linear models in the companion report. Nonlinear models for site amplification must represent the strength of the input ground motion in some manner, and peak acceleration for a reference condition (PGAr) is often used. The use of PGAr (...

Influence of Kinematic SSI on Foundation Input Motions for Bridges on Deep Foundations, PEER Report 2017-08

Benjamin J. Turner
Scott J. Brandenberg
Johnathan P. Stewart
2017

Seismic design of bridges and other pile-supported structures often utilizes a substructure method of dynamic analysis in which the foundation elements are not explicitly modeled but are replaced by springs and dashpots representing the foundation impedance. The ground motion appropriate for input to the free end of the springs, known as the “foundation input motion” (FIM), differs from the free-field motion (FFM) due to the difference in stiffness and deformation characteristics between the pile(s) and soil, which is typically overlooked in practice. Results of a parametric study of the...

Development of Time Histories for IEEE693 Testing and Analysis (Including Seismically Isolated Equipment), PEER Report 2017-10

Shakhzod M. Takhirov
Eric Fujisaki
Leon Kempner
Michael Riley
Brian Low
2017

This study was undertaken to address new developments in IEEE P693/D16 [IEEE693 WG 2017], account for the new strong-motion records from the recent major earthquakes, and assess their effects on the spectral demand. A large set of both crustal and subduction type records was investigated based on a number of parameters and intensity measures. The best candidates were selected as seed motions. The motions were matched to the IEEE693 spectrum in a time domain at 5% damping, which follows the guidance of IEEE P693/D16 [IEEE693 WG 2017]. In addition, three three-component synthetic time...

Stochastic Modeling and Simulation of Ground Motions for Performance-Based Earthquake Engineering, PEER Report 2010-02

Sanaz Rezaeian
Armen Der Kiureghian
2010

A fully nonstationary stochastic model for strong earthquake ground motion is developed. The model employs filtering of a discretized white-noise process.
Nonstationarity is achieved by varying the filter properties and modulating the intensity of the process in time. Separation of the spectral and temporal nonstationary characteristics of the process allows flexibility and ease in modeling and parameter estimation. The evolving intensity and time-varying frequency content of the process are characterized by a set of statistical measures including the mean-square intensity, the mean...

Application Guide for the Design of Flexible and Rigid Bus Connections between Substation Equipment Subjected to Earthquakes, PEER Report 2010-04

Jean-Bernard Dastous
Armen Der Kiureghian
2010

Interaction between equipment subjected to earthquakes is an area of major concern to engineers intent on seismically hardening a substation. The buswork connections installed between equipment greatly affect the seismic performance of that equipment. If the buswork is not properly designed, equipment that would otherwise survive may fail, resulting in unnecessary financial losses or reliability impact. The use of seismically designed connections, whether flexible, rigid, or a combination of both, increases the probability that a facility will still be operational after an earthquake....