PEER Reports

PEER Reports

CPT-Based Probabilistic Assessment of Seismic Soil Liquefaction Initiation, PEER Report 2005-15

Robb Eric S. Moss
R. B. Seed
Robert E. Kayen
Johnathan P. Stewart
Armen Der Kiureghian
2005

The correlation of seismic field performance with in situ index test results has been proven to be a reliable method for defining the threshold between liquefaction a nd non-liquefaction. The objective of this research was to define, in the most accurate and unbiased manner possible, the initiation of seismic soil liquefaction using the cone penetration te st (CPT). Contained in this report are the results of this research.

Case histories of occurrence and non-occurrence of soil liquefaction were collected from seismic events that occurred over the past three decades. These...

Seismic Response and Reliability of Electrical Substation Equipment and Systems, PEER Report 2005-16

Junho Song
Armen Der Kiureghian
Jerome L. Sackman
2005

Continued operation of critical lifelines after a major earthquake is essential for reduction of losses, timely delivery of emergency services, and post-earthquake recovery. An important element within the power transmission lifeline is the electrical substation, which serves to transform the power voltage for distribution in local grids. The electrical substation typically consists of a complex set of equipment items that are interconnected through either assemblies of rigid-bus and flexible connectors or through flexible cable conductors.

Estimating the seismic response and...

Earthquake Simulator Tests on Reducing Residual Displacements of Reinforced Concrete Bridge Columns, PEER Report 2005-17

Junichi Sakai
Stephen A. Mahin
Andres Espinoza
2005

Bridge columns located in regions of high seismicity are generally designed with a large ductility capacity. Although this design strategy is both economical and prevents collapse, such columns develop high ductility demands when subjected to strong-ground motion, resulting in large permanent displacements. To minimize such residual displacements in reinforced concrete (RC) columns, a design is proposed whereby longitudinal post-tensioning strands replace some of usual longitudinal mild reinforcing bars. The seismic performance of such partially prestressed RC columns under near-field...

Bracing Berkeley: A Guide to Seismic Safety on the UC Berkeley Campus, PEER Report 2006-01

Mary C. Comerio
Stephen Tobriner
Ariane Fehrenkamp
2006

Although the campus of the University of California, Berkeley has never been damaged by a major earthquake, it has undertaken one of the most comprehensive and costly seismic retrofit programs in history. After great earthquakes whole cities have been reconstructed and surviving buildings retrofitted, but at the University of California, Berkeley, it was the threat of future earthquakes that galvanized the administration, the faculty and staff to act. As of the centennial of the 1906 earthquake, most of the hazardous buildings have been retrofitted or demolished and replaced with new...

Highway Demonstration Project, PEER Report 2006-02

Anne Kiremidjian
James Moore
Yue Yue Fan
Nesrin Basoz
Ozgur Yazali
Meredith Williams
2006

A method for earthquake risk assessment of transportation network systems is presented that considers loss from damage to bridges and from opportunity costs from trips forgone due to increased traffic congestion. Earthquake hazards include ground shaking, landslides, and liquefaction. Transportation network analysis models are developed with fixed and variable travel demand assumptions. The method is applied to five counties in the San Francisco Bay Area. Four scenario earthquakes are defined: moment magnitude 7.0 and 7.5 events on the Hayward fault, and 7.5 and 8.0 events on the San...

Performance of Lifelines Subjected to Lateral Spreading, PEER Report 2006-03

Scott A. Ashford
Teerawut Juirnarongrit
2006

This report presents the results of full-scale lateral spreading tests in the port of Tokachi on Hokkaido Island, Japan, to assess the behavior of piles and pipelines subjected to lateral spreading. This research project was the joint collaboration between the University of California, San Diego (UCSD), and several Japanese organizations. Controlled blasting was used to liquefy the soil and subsequently induce lateral spreading in the 4–6% surface slope test beds. Several instrumentations including pore-pressure transducers, global positioning (GPS) units, and inclinometers, were installed...

Probabilistic Seismic Evaluation of Reinforced Concrete Structural Components and Systems, PEER Report 2006-04

Tae-Hyung Lee
Khalid M. Mosalam
2006

An accurate evaluation of the structural performance of reinforced concrete structural systems under seismic loading requires a probabilistic approach due to uncertainties in structural properties and the ground motion (referred to as basic uncertainties). The objective of this study is to identify and rank significant sources of basic uncertainties and structural components with respect to the seismic demand (referred to as the Engineering Demand Parameters, EDP) of reinforced concrete structural systems. The methodology for accomplishing this objective consists of three phases. In the...

Advanced Seismic Assessment Guidelines, PEER Report 2006-05

Paolo Bazzurro
C. Allin Cornell
Charles Menun
Maziar Motahari
Nicolas Luco
2006

This document presents guidelines for a practical assessment of the seismic performance of existing structures. Performance is measured in terms of the likelihood that a building, given a level of ground motion, can be in any one of five structural limit states after an earthquake: onset-of-damage, green tag, yellow tag, red tag, and collapse. The green-, yellow-, and red-tag states are directly related to structural post-earthquake functionality. The link between the patterns of structural damage that could be observed after a mainshock and the assignment of the appropriate limit state to...

Nonlinear Analysis of a Soil-Drilled Pier System under Static and Dynamic Axial Loading, PEER Report 2006-06

Gang Wang
Nicholas Sitar
2006

Realistic time history simulation of a soil-drilled pier system under static and dynamic load-ing is essential for the development of effective performance-based earthquake design of deep foundations. Due to the nonlinear transient nature of the system and high computational requirements, to date the application of nonlinear finite element analyses to this problem has been limited. Thus, an important aspect of numerical modeling is a soil model that is simple enough to be computationally efficient yet able to capture the cyclic stress-strain behavior. In particular, it is essential to...

Analytical Modeling of Reinforced Concrete Walls for Predicting Flexural and Coupled Shear-Flexural Responses, PEER Report 2006-07

Kutay Orakcal
Leonardo M. Massone
John W. Wallace
2006

This study investigates an effective modeling approach that integrates important material characteristics and behavioral response features (e.g., neutral axis migration, tension stiffening, gap closure, and nonlinear shear be havior) for a reliable prediction of reinforced concrete (RC) wall response. A wall macro-model was improved by implementing refined constitutive relations for materials and by incorporating a methodology that couples shear and flexural response components. Detailed calibration of the model and comprehensive correlation studies were conducted to compare the model...