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Study of Site Response at a Selected Memphis Site.
Desai, H.; Ahmad, S.; Gazetas, E. S.; Oh, M. R.
National Science Foundation, Washington, DC., October 11, 1990, 43 p.
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The influence of geological and geotechnical factors on potential ground motions in Memphis due to a 65 km distant hypothetical M sub w = 7 New Madrid earthquake has been investigated. From the study of the seismotectonic environment and the seismicity of the region, the characteristics of the design earthquake are selected. A seismological model of the radiation/attenuation of the earthquake source and of the generated waves is used to generate synthetic bedrock (hard rock) accelerograms, which are then propagated through a deep deposit of soft rock to obtain input base excitations for the near-surface soil profiles. A representative soil profile for Memphis is selected from a large number of borelog data. Propagation of the generated seismic waves through the soil profile is modeled with state-of-the-art formulations to obtain the seismic motions at the ground surface. Effects of nonlinear inelastic versus equivalent-linear analysis has also been investigated. Results are presented in the form of site-specific response spectra and a proposed design spectrum.
Seismic waves; New Madrid earthquake; Earth movements; Mathematical models; Amplification; Dynamic response; Earthquake engineering; Soil properties; Soil profiles; Memphis (Tennessee); Soil mechanics; Earthquakes