PEER Reports

PEER Reports

Dynamic Modeling of the UC San Diego NHERI Six-Degree-of-Freedom Large High-Performance Outdoor Shake Table, PEER Report 2024-07

Chin-Ta Lai
Joel P. Conte
2024

The UC San Diego Large High-Performance Outdoor Shake Table (LHPOST), which was commissioned on October 1, 2004 as a shared-use experimental facility of the National Science Foundation (NSF) Network for Earthquake Engineering Simulation (NEES) program, was upgraded from its original one degree-of-freedom (LHPOST) to a six degree-of-freedom configuration (LHPOST6) between October 2019 and April 2022. The LHPOST6 is a shared-use experimental facility of the NSF Natural Hazard Engineering Research Infrastructure (NHERI) program. A mechanics-based numerical model of the LHPOST6 able to capture...

Ground Failure of Hydraulic Fills in Chiba, Japan and Data Archival in Community Database, PEER Report 2024-06

Scott J. Brandenberg
Jonathan P. Stewart
Kenneth S. Hudson
Dong Youp Kwak
Paolo Zimmaro
Quin Parker
2024

This report describes analysis of ground failure and lack thereof observed in the Mihama Ward portion of Chiba, Japan following the 2011 M9.0 Tohoku Earthquake. In conjunction with this work, we have also significantly expanded the laboratory component of the Next Generation Liquefaction (NGL) relational database.

The district referred to as Mihama Ward is on ground composed of hydraulic fill sluiced in by pipes, thereby resulting in a gradient of soil coarseness, with coarser soils deposited near the pipes and fine-grained soils carried further away. Observations from local...

PEER Report 2024/05: "A Granular Framework for Modeling the Capacity Loss and Recovery of Regional Transportation Networks under Seismic Hazards: A Case Study on the Port of Los Angeles"

June 13, 2024

PEER has published Report No. 2024/05: "A Granular Framework for Modeling the Capacity Loss and Recovery of Regional Transportation Networks under Seismic Hazards: A Case Study on the Port of Los Angeles." It was authored by Michael Benedict Virtucio, Department of Civil and Environmental Engineering, University of California, Berkeley; Barbaros Cetiner, NHERI SimCenter; Bingyu Zhao, University of California, Berkeley; Kenichi Soga, TU Wien, Austria; Ertugrul Taciroglu, Department of Civil and Environmental Engineering University of California, Los Angeles.

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PEER Report 2024/06: "Ground Failure of Hydraulic Fills in Chiba, Japan and Data Archival in Community Database"

July 9, 2024

PEER has published Report No. 2024/06: "Ground Failure of Hydraulic Fills in Chiba, Japan and Data Archival in Community Database." It was authored by Scott J. Brandenberg, Jonathan P. Stewart, Kenneth S. Hudson, Dong Youp Kwak, Paolo Zimmaro and Quin Parker, Department of Civil and Environmental Engineering, University of California, Los Angeles, California.

Access the report and 2 page summary. Access the full listing of PEER reports...

An International Workshop on Large-Scale Shake Table Testing for the Assessment of Soil-Foundation-Structure System Response for Seismic Safety of DOE Nuclear Facilities, A Virtual Workshop – 17-18 May 2021, PEER Report 2024-03

Ramin Motamed
David McCallen
Swasti Saxena
2024

Aging infrastructure within the US Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) nuclear facilities poses a major challenge to their resiliency against natural phenomenon hazards. Examples of mission-critical facilities located in regions of high seismicity can be found at a number of NNSA sites including Lawrence Livermore National Laboratory, Los Alamos National Laboratory, and the Nevada National Security Site. Most of the nation’s currently operating nuclear facilities have already reached their operating lifetime, and most currently operating...

Two-Dimensional Debris-Fluid-Structure Interaction with the Particle Finite Element Method, PEER Report 2024-04

Minjie Zhu
Michael H. Scott
2024

In addition to tsunami wave loading, tsunami-driven debris can cause significant damage to coastal infrastructure and critical bridge lifelines. Using numerical simulations to predict loads imparted by debris on structures is necessary to supplement the limited number of physical experiments of in-water debris loading. To supplement SPH-FEM (Smoothed Particle Hydrodynamics-Finite Element Method) simulations described in a companion PEER report, fluid-structure-debris simulations using the Particle Finite Element Method (PFEM) show the debris modeling capabilities in OpenSees. A new contact...

A Granular Framework for Modeling the Capacity Loss and Recovery of Regional Transportation Networks under Seismic Hazards: A Case Study on the Port of Los Angeles, PEER Report 2024-05

Michael Benedict Virtucio
Barbaros Cetiner
Bingyu Zhao
Kenichi Soga
Ertugrul Taciroglu
2024

Earthquakes, being both unpredictable and potentially destructive, pose great risks to critical infrastructure systems like transportation. It becomes crucial, therefore, to have both a fine-grained and holistic understanding of how the current state of a transportation system would fare during hypothetical hazard scenarios. This paper introduces a synthesis approach to assessing the impacts of earthquakes by coupling an image-based structure-and-site-specific bridge fragility generation methodology with regional-scale traffic simulations and economic loss prediction models. The proposed...

Seismic Performance of Isolated Bridges Under Beyond Design Basis Shaking, PEER Report 2024-02

Claudio Sepulveda
Ricardo Bustamante
Gilberto Mosqueda
2024

Seismically isolated highway bridges are expected to provide limited service under a safety evaluation-level ground shaking with minimal to moderate damage. The behavior under shaking beyond design considerations, corresponding to a large return period seismic hazard, is not well understood and could induce significant damage. In these rare events, the seismic isolation system can be subjected to displacement demands beyond its design capacity, resulting in failure of the bearings, exceeding the clearance and pounding against the abutment backwalls, or damage propagating to other primary...

Expert Panel Recommendations for Ergodic Site Amplification in Central and Eastern North America, PEER Report 2017-04

Jonathan P. Stewart
Grace A. Parker
Joseph P. Harmon
Gail M. Atkinson
David M. Boore
Robert B. Darragh
Walter J. Silva
Youssef M.A. Hashash
2017

The U.S. Geological Survey (USGS) national seismic hazard maps have historically been produced for a reference site condition of VS30 = 760 m/sec (where VS30 is time averaged shear wave velocity in the upper 30 m of the site). The resulting ground motions are modified for five site classes (A-E) using site amplification factors for peak acceleration and ranges of short- and long-oscillator periods. As a result of Project 17 recommendations, this practice is being revised: (1) maps will be produced for a range of site conditions (as represented by V...

Response Modification of Structures with Supplemental Rotational Inertia, PEER Report 2024-01

Gholamreza Moghimi
Nicos Makris
2024

Tall, multistory, buildings are becoming increasingly popular in large cities as a result of growing
urbanization trends (United Nations Department of Economic and Social Affairs 2018). As cities
continue to grow, many of them along the coasts of continents which are prone to natural hazards,
the performance of tall, flexible buildings when subjected to natural hazards is a pressing issue
with engineering relevance. The performance of structures when subjected to dynamic loads can
be enhanced with various response modification strategies which have been traditionally...