Location

San Diego, California

Session Start Date

3-26-2001

Session End Date

3-31-2001

Abstract

System identification techniques are employed to characterize the stiffness and damping characteristics of a dense sand stratum at low dynamic excitation conditions. The identification process utilizes a large database of input-output accelerations recorded in a highly instrumented centrifuge experimental program conducted by researchers at the University of California at Davis. This paper presents a computational effort based on the recorded small shaking events, where the peak ground surface acceleration ranges from 0.05g to 0.196g in amplitude. The dynamic behavior of the prototype stiff soil site near its first resonance is modeled by that of a one-dimensional shear beam. An employed system identification process attempts to define the shear wave velocity profile and damping that provide a best match to the experimental dynamic soil response near the first resonance, along a central downhole accelerometer array. Both linear viscous and hysteretic soil models are utilized in this identification study. The identified properties are found to be consistent among the investigated events, and are in good agreement with other laboratory estimates. The calibrated (via system identification) shear beam predications were found to be an excellent match to those recorded at all central downhole accelerometer locations around the first resonance.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics

Meeting Name

Fourth Conference

Publisher

University of Missouri--Rolla

Publication Date

3-26-2001

Document Version

Final Version

Rights

© 2001 University of Missouri--Rolla, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Mar 26th, 12:00 AM Mar 31st, 12:00 AM

Identification of Small Strain Dynamic Properties of Dense Sand

San Diego, California

System identification techniques are employed to characterize the stiffness and damping characteristics of a dense sand stratum at low dynamic excitation conditions. The identification process utilizes a large database of input-output accelerations recorded in a highly instrumented centrifuge experimental program conducted by researchers at the University of California at Davis. This paper presents a computational effort based on the recorded small shaking events, where the peak ground surface acceleration ranges from 0.05g to 0.196g in amplitude. The dynamic behavior of the prototype stiff soil site near its first resonance is modeled by that of a one-dimensional shear beam. An employed system identification process attempts to define the shear wave velocity profile and damping that provide a best match to the experimental dynamic soil response near the first resonance, along a central downhole accelerometer array. Both linear viscous and hysteretic soil models are utilized in this identification study. The identified properties are found to be consistent among the investigated events, and are in good agreement with other laboratory estimates. The calibrated (via system identification) shear beam predications were found to be an excellent match to those recorded at all central downhole accelerometer locations around the first resonance.