Location

San Diego, California

Presentation Date

26 May 2010, 4:45 pm - 6:45 pm

Abstract

The Garner Valley and Wildlife sites are producing a large data set that includes very interesting observations from earthquakes in the magnitude 4 to 7 range, with peak accelerations of ~10%g, at the threshold where nonlinear effects start to become important. In addition, hundreds of smaller earthquakes are recorded each month that provide the control data representing the linear behavior of the site. With the larger motions, we begin to see pore pressure build up on the liquefaction array at both the NEES Garner Valley Array site and at the NEES Wildlife Liquefaction Array site. We present the results of simulated pore pressure generation using the observed ground motions and a nonlinear anelastic hysteretic finite difference model of the soil response. We are able to reproduce this onset of pore pressure generation that occurs under the moderate strain levels associated with these ground motions. Additional work to be completed for this conference includes the development of an empirical model to predict pore pressure generation based on observed ground motions within a saturated soil column using data from the GVDA and WLA field sites. Correlations between pore pressure data and various ground motion parameters derived from accelerometers within the vertical arrays will be shown. Continuing studies on these unique data sets are improving our understanding of the physical process that drives liquefaction.

Department(s)

Civil, Architectural and Environmental Engineering

Meeting Name

5th International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Publisher

Missouri University of Science and Technology

Document Version

Final Version

Rights

© 2010 Missouri University of Science and Technology, All rights reserved.

Creative Commons Licensing

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Observations and Analysis of Ground Motion and Pore Pressure at the Nees Instrumented Geotechnical Field Sites

San Diego, California

The Garner Valley and Wildlife sites are producing a large data set that includes very interesting observations from earthquakes in the magnitude 4 to 7 range, with peak accelerations of ~10%g, at the threshold where nonlinear effects start to become important. In addition, hundreds of smaller earthquakes are recorded each month that provide the control data representing the linear behavior of the site. With the larger motions, we begin to see pore pressure build up on the liquefaction array at both the NEES Garner Valley Array site and at the NEES Wildlife Liquefaction Array site. We present the results of simulated pore pressure generation using the observed ground motions and a nonlinear anelastic hysteretic finite difference model of the soil response. We are able to reproduce this onset of pore pressure generation that occurs under the moderate strain levels associated with these ground motions. Additional work to be completed for this conference includes the development of an empirical model to predict pore pressure generation based on observed ground motions within a saturated soil column using data from the GVDA and WLA field sites. Correlations between pore pressure data and various ground motion parameters derived from accelerometers within the vertical arrays will be shown. Continuing studies on these unique data sets are improving our understanding of the physical process that drives liquefaction.