Producing broadband synthetic time histories for central and eastern north america


Generation of artificial time histories is a promising solution in the absence of sufficient and appropriate (potentially damaging earthquake) recorded seismograms for the seismic time history analysis of structures. In this study, we propose a new method to generate seismograms appropriate for the Central and Eastern North America (CENA). Here, the broadband synthetic seismograms are generated for moment magnitudes 5.5, 6.5 and 7.5 for the CENA region. Utilizing the deterministic synthetics at low frequencies is critical to simulate the characteristics of the actual strong ground motion records like coherent ground motion pulses as well as the near fault effects like forward rupture directivity. In this study, we use the numerical technique of Spudich and Archuleta. The Green's functions which are considered as wave propagation are achieved using the discrete wavenumber finite element method. We consider a spatial random field model to characterize the complexity of the slip distribution on a heterogeneous fault. Also, uncertainties are considered in the method by applying random components in the generation process. Some results for moment magnitude of Mw=6.5 are presented. As it is expected, the effect of forward directivity in the long period velocity time histories is observed in the stations along the strike of the fault. © 2013 American Society of Civil Engineers.

Publication Title

Structures Congress 2013: Bridging Your Passion with Your Profession - Proceedings of the 2013 Structures Congress