PEER Reports

PEER Reports

Conditional Ground-Motion Model for Peak Ground Velocity for Active Crustal Regions, PEER Report 2020-05

Norman A. Abrahamson
Sarabjot Bhasin

Conditional models for the horizontal and vertical peak ground velocity (PGV), given the pseudospectral acceleration [PSA(T)] values, are developed for active crustal regions. The period of the PSA(T) used in the conditional model, TPGV , is magnitude dependent, which captures the effect of the magnitude dependence of the earthquake source corner frequency on the PGV. Conditional models can be used to estimate the PGV given a design spectrum and are applicable for magnitudes between 3.0 and 8.5, and for distances up to 200 km. The...

Partially Non-Ergodic Ground-Motion Model for Subduction Regions using the NGA Subduction Database, PEER Report 2020-04

Nicolas Kuehn
Yousef Bozorgnia
Kenneth W. Campbell
Nicholas Gregor

This report presents a summary of the development, evaluation, and comparison of a new subduc-tion ground-motion model (GMM), now known as Kuehn-Bozorgnia-Campbell-Gregor (KBCG20) model. This GMM was developed as part of the Next Generation Attenuation for Subduction Regions (NGA-Sub) program using a comprehensive compilation of subduction interface and in-traslab ground-motion recordings and metadata compiled in the NGA-Sub database. The KBCG20 model includes ground-motion scaling terms for magnitude, distance, site amplification, and basin amplification. Some of these terms are adjustable...

NGA-Subduction Global Ground-Motion Models with Regional Adjustment Factors, PEER Report 2020-03

Grace A. Parker
Jonathan P. Stewart
David M. Boore
Gail M. Atkinson
Behzad Hassani

Next Generation Attenuation Subduction (NGA-Sub) is a multi-year, multidisciplinary project with the goal of developing an earthquake ground-motion database of processed time series and ground-motion intensity measures (IMs), as well as a suite of ground-motion models (GMMs) for global subduction zone earthquakes. The project considers interface and intraslab earthquakes that have occurred in Japan, Taiwan, New Zealand, Mexico, Central America, South America, Alaska, and Cascadia. This report describes one of the resulting GMMs, one important feature of which is its ability to describe...

Data Resources for NGA-Subduction Project, PEER Report 2020-02

Yousef Bozorgnia (NGA-Sub PI)
Jonathan P. Stewart (Editor)

The NGA-Subduction (NGA-Sub) project is one in a series of Next Generation Attenuation (NGA) projects directed towards database and ground-motion model development for applications in seismic-demand characterization. Whereas prior projects had targeted shallow crustal earthquakes, active tectonic regions (NGA-West1 and NGA-West2), and stable continental regions (NGA-East), NGA-Sub is the first to address specifically subduction zones, which are a dominant source of seismic hazard in many regions globally, including the Pacific Northwest region of the United States and Canada.


Modeling Viscous Damping in Nonlinear Response History Analysis of Steel Moment-Frame Buildings: Design-Plus Ground Motions, Revision 1.0, PEER Report 2020-01

Xin Qian
Anil K. Chopra
Frank McKenna

This report investigates the question: can seismic demands on steel moment-frame buildings due to Maximum Considered Earthquake (MCER) design-level ground motions [2% probability of exceedance (PE) in 50 years] be estimated satisfactorily using linear viscous damping models or is a nonlinear model, such as capped damping, necessary? This investigation employs two models of a 20-story steel moment-frame building: a simple model and an enhanced model with several complex features. Considered are two linear viscous damping models: Rayleigh damping and constant modal damping; and...

City-Scale Multi-Infrastructure Network Resilience Simulation Tool, PEER Report 2021-05

Kenichi Soga
Renjie Wu
Bingyu Zhao
Chaofeng Want

The goal of this project is to deliver a coherent framework of simulation tools that can quantify the performance of the water distribution network (WDN) and the transportation network at the city scale under different ground-motion scenarios. In addition to tool development, this project also investigates the potential interactions between structural and infrastructure systems in the case of normal operational and various earthquake damage scenarios. A multi-threaded, high-performance computing (HPC) scalable semi-dynamic traffic simulation model has been developed to understand the...

Effective Stress Analysis of Liquefaction Sites and Evaluation of Sediment Ejecta Potential, PEER Report 2021-03

Daniel Hutabarat
Jonathan D. Bray

Sediment ejecta mechanism contributes significantly to the severity of liquefaction-induced ground failure (e.g., excessive land subsidence). Estimating the amount of ejected sediment is a key step to assess the severity of ground failure; however, procedures to quantify it are currently lacking. Sediment ejecta is a post-shaking phenomenon resulting from the migration and redistribution of excess-pore-water-pressure (ue) generated during earthquake shaking. The dissipation process of residual ue can trigger high-gradient upward seepage, which...

Towards Multi-Tier Modeling of Liquefaction Impacts on Transportation Infrastructure, PEER Report 2021-04

Brett Maurer
Mertcan Geyin
Alex J. Baird

Semi-empirical models based on in situ geotechnical tests have been the standard-of-practice for predicting soil liquefaction since 1971. More recently, prediction models based on free, readily available data have grown in popularity. These “geospatial models” rely on satellite remote sensing to infer subsurface traits without in situ tests. While the concept of such an approach is not new, the recent models of Zhu et al. [2015; 2017] are arguably the most rigorously formulated and well-trained to date. The use of such models is appealing for a range of applications, but these models have...

Use of Corridors for Decision Making in Transportation Networks in Seismic Regions, PEER Report 2021-09

Rodrigo I. Silva-Lopez
Jack W. Baker

This report presents the results of the study that proposes a retrofitting strategy to manage seismic risk via identification of what constitutes "Corridors” in transportation networks. We define a Corridor as a set of bridges that work together to ensure connectivity and traffic flow between areas of a region. We propose using a Markov clustering algorithm to detect Corridors, whereby it selects sets of bridges that correspond to highway and main road segments that are effective in reducing disruption when jointly retrofitted. We then use a two-stage stochastic optimization to identify...

Seismic Performance of Column-to-Drilled-Shaft Connections in Reinforced Concrete Bridges, PEER Report 2021-10

Michelle Chang
John Stanton
Marc Eberhard

Drilled shaft foundations are often used to support reinforced concrete bridge columns founded in soft soils or in locations where a small footprint is desired. Increasingly, the shaft is being built with a diameter larger than that of the column, to allow tolerance in the column placement and to facilitate plastic hinge formation in the column rather than in the shaft. The column–shaft connection, which involves a noncontact splice between the column and shaft bars, is a key component in this structural system. However, there is limited research on the behavior of these connections under...