Pontificia Universidad Católica de Chile Pontificia Universidad Católica de Chile
Abell J.A., de la Llera J.C. and Wicks C.W. (2011)

Enhancement of long period components of recorded and synthetic ground motions using InSAR. http://dx.doi.org/10.1016/j.soildyn.2011.01.005

Revista : Soil Dynamics and Earthquake Engineering
Volumen : 31
Número : 5-6
Páginas : 817-829
Tipo de publicación : ISI Ir a publicación


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. (C) 2011 Elsevier Ltd. All rights reserved.