US-Egypt Cooperative Research: Seismic Risk Assessment of Wind Turbine Towers in Zafarana Wind Farm Egypt

University Of California-San Diego, La Jolla CA

Investigators

Abstract

This project supports a cooperative research project by Dr Ahmed Elgamal, University of California-San Diego in collaboration with Dr. Khaled El-Zahaby, Chairman, Housing and Building national Research Center (HBRC) in Cairo, Egypt. They will performe a Seismic Risk Assessment of Wind Turbine Towers in the Zafarana Wind Farm in Egypt. The Zafarana wind farm in 2012 was generating a capacity of 517MW, making it one of the largest onshore wind farms in the world. It is located in an active seismic zone along the west side of the Gulf of Suez. An extension of the wind farm southward is under consideration for construction in the near future. Seismic risk assessment is needed to assess the structural integrity of wind towers under expected seismic hazard events in this location, and this risk assessment procedure is likely to be valuable whenever wind turbines are located in a potentially active seismic region. The project objective is to pursue interdisciplinary studies to define seismic risk and seismic loads via a range of seismic analyses that are coupled with measured structural values in the field. The ultimate goal is to define and improve seismic design of wind turbine structures. Wind turbines are unique structures. They are tall, slender and flexible and susceptible to dynamic loads. In addition, they are operating/moving structures as compared to buildings or bridges which are stationary. As alternative energy sources such as wind become more important globally, we will continue to have more wind turbine structures; therefore, pursuing research for these structures is important and broadly relevant. This international project combines a team of scientists, engineers, students and researchers from two countries. The diverse expertise of the two teams is a strength of the research effort and the cultural exchange between them is an important broader impact of this project. The research will be integrated into several facets of the structural and geotechnical engineering programs at the participating institutes. Results of this study will be of relevance to similar projects in the Middle East, as well as in other seismically active regions worldwide. Graduate and undergraduate students from the US and from Egypt will participate in the research, which ranges from numerical modeling of structure and soil structure interaction of wind turbine towers to the practical aspects of conducting a field investigation and instrumentation, thus providing a well-rounded education for the participants. In this regard, students from STEM under-represented communities will be actively recruited. Additionally, the international/intercultural collaborative aspects of the proposed research will provide a unique experience for those involved. The proposed seismological studies, geo technical studies for loads, dynamic field measurements, and structural seismic analyses of existing wind towers will greatly enhance the associated design recommendations and provide strong intellectual merit for this project. The actual estimated site loads can be applied to the new towers that will be located in the same zone. The new wind turbine ambient vibration datasets to be acquired at Zafarana will constitute a basis for calibration of analysis tools for studies elsewhere. This data will be professionally archived and made available for use by interested researchers and practitioners worldwide. Valuable recommendations will be deduced for provisions in design codes based on realistic data and detailed structural assessments of the wind turbines. This project is funded through the US-Egypt Joint Science and Technology Fund Program. Support for the U.S. side of these cooperative projects is provided to the National Science Foundation by the U.S. Department of State. The Egyptian Government provides support for the Egyptian side of the collaboration.