Current practice in earthquake engineering is to model earthquake- induced strong ground motions as accelerations occurring at single locations; or at most to use simple physical wave propagation models employing simple waveforms. This research program will develop a description of the spatial variation of earthquake ground motions that models observed motions, using data from strong-motion seismograph arrays. In addition, the effects of these spatial variations in ground motion on the response of structures will be studied. The investigation will utilize digital signal processing techniques, simulation of correlated multiple excitations, random vibration analysis, and deterministic dynamic analysis. The research has direct application to the design of structures on large foundations, such as dams and containment structures for nuclear power plants; to spatially extended structures with multiple supports such as occurs in long-span bridges and surface pipelines; and to long buried structures, including electric power, telecommunication, oil, gas, water and sewage lifelines. The principal investigator is highly qualified and has the institutional facilities available to undertake the proposed research program.
