Scaling and Estimation of Earthquake Ground Motion as a Function of the Earthquake Source Parameters and Distance

摘要

This report reviews the various methodologies currently available to predict the near-source ground motion from an earthquake. The limitations of the various approaches are discussed in light of recently developed theory and recored data. To overcome some of the limitations of available approaches, the author developed improved rules for scaling between earthquakes. Ground-motion data obtained from salvo (line source) explosions are also investigated to gain insight into the appropriate form for the attenuation of peak acceleration and peak velocity. The scaling laws are combined with the appropriate attenuation relations and the data from the 1971 San Fernando and 1940 Imperial Valley earthquakes to obtain relations among the key source parameters: dynamic stress drop and equivalent radius of the highly stressed region, distance from the center of energy release, and peak ground acceleration and velocity. These relations are verified by comparing the predicted levels of ground motion to those actually recorded from a number of earthquakes. The relations among earthquake magnitude, earthquake source parameters, and peak ground motion are discussed.