PEER Reports

PEER Reports

Effects of Connection Hysteretic Degradation on the Seismic Behavior of Steel Moment-Resisting Frames, PEER Report 2003-13

Janise E. Rodgers
Stephen A. Mahin
2003

Fractures observed at the welded beam-column connections in steel moment-resisting frames after recent earthquakes have led structural engineers to investigate the hysteretic behavior of such connections. Extensive research was subsequently performed on connections, and much is now known about their behavior. However, the same cannot be said for the effects of this behavior on overall system response, particularly if degradation occurs in connection strength or stiffness. Some analytical studies have been performed, but experimental data are virtually nonexistent for systems with degrading...

Finite Element Reliability and Sensitivity Methods for Performance-Based Earthquake Engineering, PEER Report 2003-14

Terje Haukaas
Armen Der Kiureghian
2003

The work in this report is motivated by the performance-based engineering approach advocated by PEER. A comprehensive, object-oriented software framework for finite element sensitivity and reliability analysis is developed. The work builds on the existing software OpenSees.

An essential ingredient in finite element reliability analysis is accurate, consistent and efficient computation of response sensitivities. Using the direct differentiation method, a unified formulation of finite element response sensitivities with respect to material, load and shape parameters is developed and...

Seismic Demands for Non-deteriorating Frame Structures and Their Dependence on Ground Motions, PEER Report 2003-15

Ricardo Medina
Helmut Krawinkler
2003

The objective of this study is to improve the understanding of behavior patterns and the quantification of seismic demands for nondeteriorating regular fr ames subjected to ordinary ground motions. In this study, the term ordinary refers to ground motions that are recorded at distances greater than 13 km from the fault rupture, that do not exhibit pulse-type characteristics, and that are recorded on stiff soil sites. Engineering demand parameters (EDPs) of interest include roof and story drifts, local deformations, absolute floor accelerations and velocities, story shears and...

Seismic Demands for Performance-Based Design of Bridges, PEER Report 2003-16

Kevin Mackie
Bozidar Stojadinovic
2003

The Pacific Earthquake Engineering Research Center is developing a probabilistic performance- based earthquake engineering framework, one component of which is a seismic demand model. Probabilistic seismic demand analysis was used to compute values of bridge-specific engineering demand parameters (EDP), such as curvature ductility, given ground motion intensity measures (IM), such as peak ground acceleration. A representative relation between chosen IM-EDP pairs forms the basis of the probabilistic seismic demand models (PSDM) presented.

The objective of this report was the...

Predicting Earthquake Damage in Older Reinforced Concrete Beam-Column Joints, PEER Report 2003-17

Catherine Pagni
2003

Fragility functions are developed that predict the method of repair required for older reinforced concrete beam-column joints damaged by earthquake loading. The results of previous experimental studies are used to develop empirical relationships between damage states and traditional measures of earthquake demand, such as interstory drift, joint deformation, and number of load cycles. Damage states are proposed and linked deterministically with commonly employed MORs; these damage states are characterized by parameters such as concrete crack width, extent of concrete spalling, and yielding...

Performance Models for Flexural Damage in Reinforced Concrete Columns, PEER Report 2003-18

Michael Berry
Marc Eberhard
2003

To implement performance-based earthquake engineering (PBEE), it is necessary to assess the probability of reaching multiple damage states in structural and nonstructural elements. To help with this assessment, the research presented in this report provides practical recommendations for estimating the likelihood that in a reinforced concrete column the concrete cover will have begun to spall or the longitudinal bars will have begun to buckle, based on the column’s expected deformation demand.

Damage development in reinforced concrete columns is complex, involving three- dimensional...

Empirical Characterizations of Site Conditions on Strong Ground Motion, PEER Report 2005-01

Jonathan P. Stewart
Yoojoong Choi
Robert W. Graves
2005

Empirical relationships are developed to predict amplification factors for 5% damped response spectral acceleration as a function of site condition. Amplification factors are evaluated as residuals between ground motion recordings and predictions from modified rock attenuation relationships.

Both shallow and deep characteristics of site condition are considered to identify those parameters that are most effective from the standpoint of bias and dispersion reduction. The parameterization of shallow site condition is based on (1) surface geology, (2) NEHRP classification, (3)...

Fragility Basis for California Highway Overpass Bridge Seismic Decision Making, PEER Report 2005-02

Kevin R. Mackie
Bozidar Stojadinovic
2005

The seismic loss modeling of transportation networks is a multifaceted procedure for calculating monetary losses due to damage to the transportation links in an earthquake. This report focuses on providing a rational method to evaluate da mage potential and to assess probable highway bridge losses for critical decision making regarding the post-earthquake safety and repair of a highway network. Loss fragilities were defined for each individual bridge using PEER’s performance-based earthquake engineering framework. Decision variables were related to earthquake intensity through a series of...

A Taxonomy of Building Components for Performance-Based Earthquake Engineering, PEER Report 2005-03

Keith A. Porter
2005

To model the seismic performance of building components, they must first be defined. A categorization system (or taxonomy) of components is developed here, including both structural and nonstructural elements but focusing on the latter. Structural elements are those that are part of the structure’s vertical- or
lateral-force-resisting system. Nonstructural components are generally those that are attached to a structure but are not considered part of either system. Taxonomic groups are defined to meet ten objectives to ensure that meaningful fragility functions can be created for a...

Numerical Modeling of the Nonlinear Cyclic Response of Shallow Foundations, PEER Report 2005-04

Chad Harden
Tara Hutchinson
Geoffrey R. Martin
Bruce L. Kutter
2005

Understanding the nonlinear behavior of shallow building foundations under large-amplitude loading is an important aspect of performance-based earthquake engineering (PBEE). Soil yielding beneath foundations can be an effective energy-dissipation mechanism; however, this yielding may lead to excessive permanent deformations. The objective of this report is to develop and test procedures to account for foundation nonlinearity and uplift in PBEE

In order to accurately represent PBEE in current design, a Winkler-type finite element mesh generator is written to simulate a shallow strip...