Location
San Diego, California
Presentation Date
30 Mar 2001, 1:30 pm - 3:30 pm
Abstract
Microtremor measurements are conducted using arrays of sensors at six strong motion stations in Taiwan where the peak ground accelerations over 400 cm/s2 were recorded during the 1999 Chi-Chi earthquake. Shallow shear wave velocity profiles of these stations are estimated based on an inverse analysis of microtremor dispersion characteristics and H/V spectra. At Wufeng (TCU065) where building damage was the most extensive among others, a thick soft surface layer with a shear wave velocity less than or equal to about 200 m/s overlies a stiff layer with Vs greater than 400 m/s at a depth of about 30 m. At other stations, stiff layers with Vs greater than 300-400 m/s occur from the ground surface or at a depth less than 20 m. Linear and equivalent linear analyses are conducted using the estimated Vs profiles. The natural site periods computed from an equivalent linear analysis are generally consistent with the peak periods of the response acceleration spectra of the recorded strong motions, but they are considerably longer than those estimated from a linear analysis, regardless of the value of the shallow shear wave velocity. This suggests that local soil conditions including nonlinear soil behavior might have had significant effects on the ground surface motion and performance of buildings during the earthquake.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
4th International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Publisher
University of Missouri--Rolla
Document Version
Final Version
Rights
© 2001 University of Missouri--Rolla, All rights reserved.
Creative Commons Licensing
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
Recommended Citation
Tokimatsu, Kohji and Sekiguchi, Toru, "Site Effects Estimated From Microtremor Measurements at Selected Strong Motion Stations in Taiwan" (2001). International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics. 21.
https://scholarsmine.mst.edu/icrageesd/04icrageesd/session03/21
Included in
Site Effects Estimated From Microtremor Measurements at Selected Strong Motion Stations in Taiwan
San Diego, California
Microtremor measurements are conducted using arrays of sensors at six strong motion stations in Taiwan where the peak ground accelerations over 400 cm/s2 were recorded during the 1999 Chi-Chi earthquake. Shallow shear wave velocity profiles of these stations are estimated based on an inverse analysis of microtremor dispersion characteristics and H/V spectra. At Wufeng (TCU065) where building damage was the most extensive among others, a thick soft surface layer with a shear wave velocity less than or equal to about 200 m/s overlies a stiff layer with Vs greater than 400 m/s at a depth of about 30 m. At other stations, stiff layers with Vs greater than 300-400 m/s occur from the ground surface or at a depth less than 20 m. Linear and equivalent linear analyses are conducted using the estimated Vs profiles. The natural site periods computed from an equivalent linear analysis are generally consistent with the peak periods of the response acceleration spectra of the recorded strong motions, but they are considerably longer than those estimated from a linear analysis, regardless of the value of the shallow shear wave velocity. This suggests that local soil conditions including nonlinear soil behavior might have had significant effects on the ground surface motion and performance of buildings during the earthquake.
