This award is an outcome of the NSF 08-519 program solicitation George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Research (NEESR) competition and includes the University of California, San Diego (UCSD) (lead institution) and Harvey Mudd College (sub-award). This project will utilize the NEES equipment sites at the University of California, Los Angeles (UCLA) and the University of California, San Diego (UCSD). The research outcomes will allow engineers to appropriately and economically account for seismic loading on wind turbines. This will further facilitate expansion of a main source of Green renewable energy, and ensure minimal disruption to the critical resource that wind power provides. The project will be conducted in collaboration with industry representatives in order to further focus the research effort on the most significant practical needs today. Related educational outreach activities will allow undergraduate students to participate in the utilization of the involved NEES world class testing facilities. In addition, the project team will develop related internet dissemination applications for K-12 and undergraduate students. In the United States, the 2006 investment in wind turbines was on the order of $4 billion. This growth shows no sign of slowing with the Department of Energy (DOE) goal of expanding the number of wind turbines fivefold by 2015. A significant portion of this growth is in earthquake prone states. For instance, more than a quarter of the new capacity installed in 2005 and 2006 was in the seismically vulnerable States of California and Washington. New wind turbines are also becoming increasingly taller and heavier, standing vertically in excess of 200 feet (taller than a twenty-story building), and thus increasing the significance of potential earthquake loads. If seismically vulnerable, numerous turbines of a given vintage in a large wind farm may be damaged, leading to substantial economic consequences. In order to address this challenge, the proposed research will utilize NEES facilities to provide the needed experimental data and insights for developing validated rational analysis and design procedures. The NEES equipment operated by UCLA will be used to conduct a comprehensive field investigation to quantify the dynamics of actual operating wind turbines. Experiments using the outdoor UCSD NEES shake table will provide insight into the potential damage modes of wind turbines when subjected to earthquake shaking. Findings from these tests will be used to construct and validate computational models that will further extend the testing results. These models will be used to develop a framework for seismic analysis and design of wind turbines. Intellectual merit in this effort stems from providing the first experimentally validated seismic design procedure for wind turbines worldwide. Data from this project will be made available through the NEES data repository (www.nees.org).
