Project Website
www.nees-cityblock.org

Sponsor

NSF Logo
Funding support provided by the
National Science Foundation
under Grant no.: CMMI-0721399

CUREE Projects
Membership Information
Faculty Position Openings
Member Database
CUREE Newsletters

Projects : NEES Cityblock : Document Archive

Soil-Structure Interaction on the Scale of a City Block

Seismic Performance Assessment in Dense Urban Environments

ARTICLES AND REPORTS

Centrifuge Testing to Evaluate and Mitigate Liquefaction-Induced Building Settlement Mechanisms

Shideh Dashti, Jonathan D. Bray, Juan M. Pestana, Michael Riemer, and Dan Wilson

From JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING © ASCE / JULY 2010

ABSTRACT: The effective application of liquefaction mitigation techniques requires an improved understanding of the development and consequences of liquefaction. Centrifuge experiments were performed to study the dominant mechanisms of seismically induced settlement of buildings with rigid mat foundations on thin deposits of liquefiable sand. The relative importance of key settlement mechanisms was evaluated by using mitigation techniques to minimize some of their respective contributions. The relative importance of settlement mechanisms was shown to depend on the characteristics of the earthquake motion, liquefiable soil, and building. The initiation, rate, and amount of liquefaction-induced building settlement depended greatly on the rate of ground shaking.

Earthquake Input Motions and Seismic Site Response in a Centrifuge Test Examining SFSI Effects

Ben Mason

56th International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics (05.24.10)

ABSTRACT: This paper describes the ground motion selection process and reports observed seismic site response and SFSI effects during a dynamic centrifuge test (Test-1). The centrifuge test is the first in a series of tests examining the effects of SFSI in dense urban environments. The objective of Test-1 is to examine SFSI effects for two structures that are located a significant distance apart and essentially isolated. The model structures represent a three-story building founded on spread footings and a nine-story structure founded on a three-story basement. The structures are sited on a dry, dense bed of Nevada Sand. The centrifuge model is subjected to a series of shaking events that represent near-fault and “ordinary” ground motions at a site in Los Angeles. Results show that site periods degrade as ground motion intensity increases with more pronounced degradation observed for near-fault ground motions as compared with ordinary ground motions. Additionally, the results indicate the importance of kinematic effects of embedded structures when considering SFSI effects.

Graduate Students Mentoring Undergraduate Researchers on a Large-scale Experimental Research Project - A Case Study

Gregg L. Fiegel (Cal Poly, SLO), H. Ben Mason (UC Berkeley), and Nicholas W. Trombetta (UC San Diego)

Article published for the American Society of Engineering Education (ASEE)

ABSTRACT: The paper describes our strategies and experiences in recruiting, training, advising, and mentoring five undergraduate student researchers for a large-scale experimental research project. Specific discussions focus on the development of student learning outcomes and the establishment of a recruiting program. For this project, graduate student leaders served as the primary mentors to the undergraduate researchers.

Mechanisms of Seismically Induced Settlement of Buildings with Shallow Foundations on Liquefiable Soil

Shideh Dashti, Jonathan D. Bray, Juan M. Pestana, Michael Riemer, and Dan Wilson

From JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING © ASCE / JULY 2010

ABSTRACT: Seismically induced settlement of buildings with shallow foundations on liquefiable soils has resulted in significant damage in recent earthquakes. Engineers still largely estimate seismic building settlement using procedures developed to calculate postliquefaction reconsolidation settlement in the free-field. A series of centrifuge experiments involving buildings situated atop a layered soil deposit have been performed to identify the mechanisms involved in liquefaction-induced building settlement. Previous studies of this problem have identified important factors including shaking intensity, the liquefiable soil’s relative density and thickness, and the building’s weight and width.

NEES City Block - Design Spectra For Project Location No.1

Ben Mason and Jonathan Bray

ABSTRACT: The purpose of this memorandum is to examine the seismic hazard of a selected project location for the ‘NEES City Block’ project. With this information, the research team, as well as the professional practice committee, can decide whether to make this the permanent project location, or whether another site should be selected.

Seismic Performance Assessment in Dense Urban Environments: Evaluation of Nonlinear Building Foundation Systems Using Centrifuge Tests

ZhiQiang Chen

56th International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics (05.24.10)

ABSTRACT: In dense urban areas, buildings are generally constructed in clusters, forming city blocks. New buildings are designed assuming their response is independent of adjacent buildings, which ignores potentially important structure-soil-structure-interaction (SSSI) effects. Although a few studies have revealed the significance of SSSI effects, validated simulation and design tools do not exist. In this paper, we present the results from the first in a series of centrifuge tests intended to investigate SSSI effects. Results herein are focused on the design and measured response of two model building-foundation systems placed on dense dry Nevada sand and tested at 55-g. The two models represent prototypical nine-story and three-story special moment resisting frame buildings, with the former structure supported by a three-level basement-mat and the later on isolated spread footings. Nonlinear response-history simulations are performed to aid in the design of the models, with particular attention to reproducing prototype building periods and nonlinear characteristics. Yielding of the model buildings is achieved using custom-designed fuses placed strategically throughout the superstructures. At present, the two models are placed as far apart as possible to characterize soil-structure interaction on individual buildings; subsequent experiments will move the structures in near proximity, allowing direct experimental assessment of structuresoil- structure-interaction.

Seismic Structure-Soil-Structure Interaction in Nuclear Power Plant Structures

Chandrakanth Bolisetti and Dr. Andrew Whittaker

From the SMIRT 21 - 21st International Conference on Structural Mechanics in Reactor Technology 6-11, 2011, New Delhi

Seismic System Identification using Centrifuge-based Soil-Structure Interaction Test Data

Z. Chen, N.W. Trombetta, T.C. Hutchinson, H.B. Mason, J.D. Bray and B.L. Kutter

From JOURNAL OF EARTHQUAKE ENGINEERING (2013)

ABSTRACT: This paper presents a framework for conducting seismic system identification using geotechnical centrifuge-based data for soil-structure interaction (SSI) experimentation. The framework starts with a design step that calculates two important SSI parameters: the period-lengthening ratio and the foundation-damping ratio. An identification and approximation procedure is further developed to estimate the system parameters at a variety of boundary conditions. The framework is then applied to two centrifuge tests. The results illustrate that the proposed framework can improve both the understanding of complex seismic soil-structure response and the use of geotechnical centrifuge-based SSI test data.

Soil-Foundation-Structure Interaction Effects on Model Buildings within a Geotechnical Centrifuge

H. B. Mason (UCB), Z. Chen, K. C. Jones (UCB), N. W. Trombetta (UCSD), J. D. Bray (UCB), T. C. Hutchinson (UCSD), C. Bolisetti (UB-SUNY), A. S. Whittaker (UB-SUNY), B. Y. Choy (UCD), B. L. Kutter (UCD), and G. L. Fiegel (CalPoly-SLO)

ABSTRACT: This paper describes a geotechnical centrifuge test that is part of a study investigating soil-foundation-structure interaction effects in dense urban environments. Two prototypical structures, a three-story building on spread footings and a nine-story building on a three-story basement, are located sufficiently far apart to be considered isolated from each other. The results show that kinematic soil-foundation-structure interaction is important for structures founded on deep, stiff basements. Additionally, acceleration amplification factors from the ground to roof levels of these buildings are under two and during intense motions, more than 50% of the roof drift of the shallow spread footing-supported structure is attributed to foundation movements. For lower intensity motions, the foundation movements only contribute approximately 20% of the roof drift.

Soil-Structure/Adjacent Structure Interaction

Vitelmo Bertero

excerpt from Connections - The EERI Oral History Series [reprinted by permission]

What's Fail-Safe For A Dam?

article from MOSAIC (July/August 1979)

DESCRIPTION: Geotechnical engineers seek - and find - ways to test massive structures to failure without waiting for them to fail.

 

 


© CUREE. All rights reserved.
Consortium of Universities for Research in Earthquake Engineering
last updated 06.05.14