PEER Reports

PEER Reports

Performance Evaluation of Innovative Steel Braced Frames, PEER 2009-103

T. Y. Yang
Jack P. Moehle
Bozidar Stojadinovic
2009

Adoption of new structural systems is hampered by the lack of a comprehensive method to evaluate their seismic performance. This report introduces a seismic performance evaluation procedure and demonstrates its application for the suspended zipper braced frame. The performance evaluation procedure includes laboratory and computer simulations. The laboratory simulations may be necessary in cases where behavior of a structural system or its components is inadequately understood and therefore cannot be modeled confidently for computer simulation. By integrating the laboratory specimen...

Advanced Implementation of Hybrid Simulation, PEER Report 2009-104

Andreas H. Schellenberg
Stephen A. Mahin
Gregory L. Fenves
2009

Experimental testing of structures under simulated seismic loading is one of the best approaches to gain knowledge about the response and behavior of structures during earthquakes and to confirm the effectiveness of design methods for new earthquake-resistant structures and the retrofit of existing structures. Hybrid simulation, where a test is executed based on a step-by-step numerical solution of the governing equations of motion for a hybrid model formulated considering both the numerical and physical portions of a structural system, is one of the well-established experimental testing...

Reduced Uncertainty of Ground Motion Prediction Equations through Bayesian Variance Analysis, PEER Report 2009-105

Robb Eric S. Moss
2009

A ground motion prediction equation estimates the mean and variance of ground shaking with distance from an earthquake source. Current relationships use regression techniques that treat the input variables or parameters as exact, neglecting the uncertainties associated with the measurement of shear wave velocity, moment magnitude, and site-to-source distance. This parameter uncertainty propagates through the regression procedure and results in model uncertainty that overestimates the inherent variability of the ground motion. This report discusses methods of estimating the statistical...

Experimental and Computational Evaluation of Current and Innovative In-Span Hinge Details in Reinforced Concrete Box-Girder Bridges: Part 2: Post-Test Analysis and Design Recommendations, PEER Report 2009-107

Matias A. Hube
Khalid M. Mosalam
2009

This report focuses on post-test finite element analysis (FEA) of and design recommendations for in-span hinges (ISHs) of reinforced concre te (RC) box-girder bridges when subjected to vertical loads through the bearings. ISHs are disturbed regions due to a complex three- dimensional (3D) stress state caused by the concentrated bearing loads and the possible existence of utility and maintenance openings. The common modeling practice for ISHs is the use of simplified two-dimensional (2D) modeling as short cantilevers, following standard procedures, e.g., those in ACI318. Such simplified...

Shear Strength Models of Exterior Beam-Column Joints without Transverse Reinforcement, PEER Report 2009-106

Sangjoon Park
Khalid M. Mosalam
2009

This study suggests a semi-empirical model and an analytical model to predict the shear strength of reinforced concrete (RC) exterior beam-column joints without transverse reinforcement (denoted as unreinforced) in the joint region. A large experimental data set of unreinforced exterior beam-column joints from published literature is collected using consistent criteria. From the parametric study of the database, it is proved that the shear strength of unreinforced exterior beam-column joints is significantly influenced by two parameters: (1) the joint aspect ratio, and (2) the beam...

PEER Lifelines Geotechnical Virtual Data Center, PEER Report 2009-108

J. Carl Stepp
Daniel J. Ponti
Loren L. Turner
Jennifer N. Swift
Sean Devlin
Yang Zhu
Jean Benoit
John Bobbitt
2009

This report describes in detail the technical specifications and results of the COSMOS/PEER-LL 2L03 project. The main goal of this project was to implement a fully functional online “Geotechnical Virtual Data Center” (GVDC), employing the most current geotechnical and geophysical (geosciences) data standards and web-based dissemination technology. The GVDC is intended to operate as a public, private, or possibly commercial web-based, one-stop center for sharing and disseminating geosciences data in accordance with the policy requirements of each entity that shares data via the G VDC. These...

Simulation and Performance-Based Earthquake Engineering Assessment of Self-Centering Post-Tensioned Concrete Bridge Systems, PEER Report 2009-109

Won K. Lee
Sarah L. Billington
2009

The focus of this research is on conducting a performance-based earthquake engineering assessment of self-centering bridge columns for structural concrete bridges. Standard highway bridges in highly seismic regions are typically designed for columns to undergo large inelastic deformations during severe earthquakes, which can result in residual displacements. These residual displacements are a measure of post-earthquake functionality in bridges, and can determine whether a bridge remains usable following an earthquake. To mitigate the effects of residual displacements, a number of self-...

Evaluation of Ground Motion Selection and Modification Methods: Predicting Median Interstory Drift Response of Buildings, PEER Report 2009-01

Curt B. Haselton
2009

Nonlinear dynamic analysis of structures is becoming increasingly prevalent in code and regulatory documents prescribing design and analysis. A recurring challenge for both practicing engineers and developers of such documents is the selection and modification of ground motions for these nonlinear dynamic analyses. Nonlinear structural response is often highly sensitive to the selection and modification of input ground motions, and many ground motion selection and modification (GMSM) methods have been proposed. No systematic studies exist that provide impartial guidance to engineers...

Improving Earthquake Mitigation through Innovations and Applications in Seismic Science, Engineering, Communication, and Response, PEER Report 2009-02

Proceedings of a U.S.-Iran Seismic Workshop June 29 July 1, 2009 Irvine, California
2009

The second U.S.-Iran seismic workshop was held on June 29–July 1, 2009, at the Arnold and Mabel Beckman Center of the National Academies of Sciences and Engineering, Irvine, California. The workshop was supported by the U.S. National Academy of Sciences in collaboration with the Pacific Earthquake Engineering Research Center, and Sharif University of Technology. The theme of this workshop was Improving Earthquake Mitigation through Innovations and Applications in Seismic Science, Engineering, Communication, and Response.

This report contains the co lection of the papers...

The Integration of Experimental and Simulation Data in the Study of Reinforced Concrete Bridge Systems Including Soil-Foundation-Structure Interaction, PEER Report 2009-03

Matthew Dryden
Gregory L. Fenves
2009

The seismic response of reinforced concrete bridges must include consideration of the whole system including soil-foundation-structure interaction (SFSI). Simulation models validated against the results of experimental tests are required to provide an accurate prediction of the bridge system response. Performance-based engineering necessitates large-scale parameter studies of these simulation models to quantify the demand for varying levels of seismic hazard. The goal of this research is to characterize the SFSI effects for a range of hazard levels by using calibrated models from the...