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Seismic Strain Induced in the Ground During Earthquakes.
Sugimura, Y.
National Science Foundation, Washington, D.C., June 1977, 73 p.
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This report develops a method of estimating seismic ground strain by using techniques for strong motion data and presents some computed results from these techniques. Simple plane wave forms are applied to seismic records for an estimation of strain. The two earthquakes selected for this study have shallow focal depths and strong ground motions. For these earthquakes the parallel and normal directions to the causative fault line are shown to form a pair of orthogonal axes, along which the mean square intensities of the components of ground motion have maximum and minimum values. The velocity curves are transformed to this coordinate system. Then the seismic shear strain component at each frequency is evaluated by applying Fourier analysis and the simple plane wave solution.
Ground motion; Computer programs; Earthquake engineering; Earthquakes; RUNF1 computer program; Plane waves; Soil dynamics; Secondary waves; Earth movements; Strains; Soil mechanics; California; CORFA computer program; CORIN computer program; Seismic waves