PEER Reports

PEER Reports

Characterization of Large Velocity Pulses for LaboratoryTesting, PEER Report 2002-22

Kenneth E. Cox
Scott A. Ashford
2002

The occurrence of a greater than magnitude 6 earthquake in an urban setting is a rare event; however, structural performance during such an earthquake is an important consideration. Unique to the near-fault region (less than 10 km) is the occurrence of a large pulse in the velocity time history trace. This large velocity pulse occurs when the conditions of forward directivity are met.

The ability to capture pulse-type ground motions in the near-fault region is of recent development and records of this type are few. The 1994 Northridge, California, and 1995 Kobe, Japan, earthquakes...

Effects of Large Velocity Pulses on Reinforced Concrete Bridge Columns, PEER Report 2002-23

Greg L. Orozco
Scott A. Ashford
2002

The study of near-field effects has been ongoing since the 1971 San Fernando earthquake in California. However, not until the 1994 Northridge earthquake in the Los Angeles area and the 1995 Kobe earthquake in Japan, where fault ruptures occurred near high-density urban settings, did structural engineers take an interest in how large velocity pulses affect structures. The large velocity pulse is a characteristic of near-field motion, which is described as the cumulative effect of almost all of the seismic radiation concentrated in one location.

To study the effects of the large...

Performance of Beam to Column Bridge Joints Subjected to a Large Velocity Pulse, PEER Report 2002-24

Natalie Gibson
André Filiatrault
Scott A. Ashford
2002

The destructive effects of velocity pulses were first recorded during the 1971 San Fernando, California, earthquake. However, the actual near-field behavior of a rupturing fault remained undefined until the 1994 Northridge, California, and 1995 Kobe, Japan, earthquakes. A large amount of data were gathered from
structural damage and strong ground motion recording stations, allowing engineers to more fully understand the near-field seismic environment. This prompted investigations into the performance of bridges, which often have natural periods close to those of recorded velocity...

Shake Table Tests and Analystical Studies on the Gravity Load Collapse of Reinforced Concrete Frames, PEER Report 2003-01

Kenneth John Elwood
Jack P. Moehle
2003

The collapse vulnerability of reinforced concrete building frames constructed before the
introduction of modern seismic codes has been well documented by earthquake reconnaissance, but the mechanisms that lead to collapse are not yet well understood. The collapse of a structure can occur only if the structure loses its ability to support gravity loads. Among other causes, the loss of gravity load capacity can result from column buckling, unseating of the supported beam, P-δ instability, or degradation of axial capacity due to column shear failure. This last cause and the effect of the...

Software Framework for Collaborative Development of Nonlinear Dynamic Analysis Program, PEER Report 2003-02

Jun Peng
Kincho H. Law
2003

This report describes the research and prototype implementation of an Internet-enabled software framework that facilitates the utilization and the collaborative development of a nonlinear dynamic analysis program by taking advantage of object-oriented modeling, distributed computing, database, and other advanced computing technologies. This new framework allows users easy access to the analysis program and the analysis results by using a web browser or other application programs, such as MATLAB. In addition, the framework serves as a common finite element analysis platform for which...

Probabilistic Response Assessment for Building-Specific Loss Estimation, PEER Report 2003-03

Eduardo Miranda
Hesameddin Aslani
2003

The use of economic losses as measure of seismic performance is proposed. A methodology is developed to evaluate the expected annual loss in buildings resulting from the occurrence of earthquake ground motions. The methodology uses a component-based approach to estimate the expected loss in buildings.

A primary step in building loss estimation is a probabilistic evaluation of the structural response. A procedure aimed at computing the probability of exceedance of different types of engineering demand parameters (EDPs) is proposed. Emphasis is given to the estimation of the...

Experimental Assessment of Columns with Short Lap Splices Subjected to Cyclic Loads, 2003-04

Murat Melek
John W. Wallace
Joel P. Conte
2003

Splices in reinforced concrete columns in older buildings, or within the nonparticipating frames in some newer buildings, were typically designed as compression lap splices. Compression lap lengths are typically short (20 to 24db ), and only light transverse reinforcement is provided over the lap length. Observations of column damage following earthquakes have revealed that these splices perform poorly; however, relatively sparse information exists to assess the expected performance for typical conditions. To address these needs, a PEER Center research program was undertaken at...

Response Assessment of Nonstructural Building Elements, PEER Report 2003-05

Shahram Taghavi
Eduardo Miranda
2003

A database is developed in this study for the adequate organization, storage, and easy retrieval of information related to the seismic performance of nonstructural components and contents of commercial buildings. The database addresses several problems and aspects of nonstructural components including damage and cost information. The performance of nonstructural components including damage descriptions and information about ground motions and structures are investigated and collected in the database. Also included are numerous photos of damaged components with a detailed damage description...

Performance of Circular Reinforced Concrete Bridge Columns Under Bidirectional Earthquake Loading, PEER Report 2003-06

Mahmoud M. Hachem
Stephen A. Mahin
Jack P. Moehle
2003

The behavior of ductile reinforced concrete bridge columns subj ected to cyclic loading has been the subject of extensive research. It is now possible to predict with fair accuracy the strength and deformation capacities of those columns given a variety of parameters that include the section geometry, amounts of longitudinal and transverse reinforcement, slenderness ratio, axial load and material strengths. Nonetheless, some areas of uncertainty remain, including the response of such columns when subjected to one or more components of intense earthquake ground motions, and the ability of...

Uncertainty Specification and Propagation for Loss Estimation Using FOSM Method, PEER Report 2003-07

Jack W. Baker
C. Allin Cornell
2003

The estimation of repair costs in future earthquakes is one component of loss estimation currently being developed for use in performance-based engineering. An important component of this calculation is the estimation of total uncertainty in the result, as a result of the many sources of uncertainty in the calculation. Monte Carlo simulation is a simple approach for estimation of this uncertainty, but it is computationally expensive. The procedure proposed in this report uses the first-order second-moment (FOSM) method to collapse several conditional random variables into a single...