The University of California at Davis is in the process of designing an earthquake simulator for their National Geotechnical Centrifuge (NGC). The purpose of this award is to support a three-person committee to oversee the design of this simulator. The committee members consist of a geotechnical engineer having expertise in the design, installation and operation of an earthquake simulator having the same operational principle as the one being designed; a structural engineer with expertise in the dynamics of structures, especially with respect to statistical aspects of the analysis and performance; and a mechanical engineer experienced in the design and analysis of rotating devices, including motors and drive systems. The oversight involves technical studies and selected experiments, some of which are performed by the committee, and some by the University of California at Davis. The goals of this committee are to: (a) Examine the operational conditions and capabilities of the NGC through calculations of the modal shapes and frequencies of the entire system; as well as through selected experiments using the instrumented centrifuge; (b) Assess the capabilities of the proposed earthquake simulator, acting alone; (c) Examine through experiment and numerical simulations the interaction of the mounted simulator with the other centrifuge components; (d) Integrate the above results to assess the expected shaking performance of the system with the centrifuge rotating, the repeatability and reliability of the motions generated, the safety of the facility, and the effect of the operation of the shaking system on the fatigue life of the centrifuge.
