Enhancement of long period components of recorded and synthetic ground motions using InSAR

J.A. Abell; J. Carlos de la Llera; Charles W. Wicks

doi:10.1016/j.soildyn.2011.01.005

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Enhancement of long period components of recorded and synthetic ground motions using InSAR

J.A. Abell·J. Carlos de la Llera·Charles W. Wicks

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Abstract

Tall buildings and flexible structures require a better characterization of long period ground motion spectra than the one provided by current seismic building codes. Motivated by that, a methodology is proposed and tested to improve recorded and synthetic ground motions which are consistent with the observed co-seismic displacement field obtained from interferometric synthetic aperture radar (InSAR) analysis of image data for the Tocopilla 2007 earthquake ( M w =7.7) in Northern Chile. A methodology is proposed to correct the observed motions such that, after double integration, they are coherent with the local value of the residual displacement. Synthetic records are generated by using a stochastic finite-fault model coupled with a long period pulse to capture the long period fling effect. It is observed that the proposed co-seismic correction yields records with more accurate long-period spectral components as compared with regular correction schemes such as acausal filtering. These signals provide an estimate for the velocity and displacement spectra, which are essential for tall-building design. Furthermore, hints are provided as to the shape of long-period spectra for seismic zones prone to large co-seismic displacements such as the Nazca-South American zone.

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Soil Dynamics and Earthquake Engineering Article

Source-reported bounding extent: -24.226928664976363° to -20.910134481692673° latitude; -71.224365234375° to -68.631591796875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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J.A. Abell, J. Carlos de la Llera, Charles W. Wicks. 2011. Enhancement of long period components of recorded and synthetic ground motions using InSAR. https://doi.org/10.1016/j.soildyn.2011.01.005

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