The design of structures under winds worldwide is governed by a unique set of design limit states that encompass not only survivability and serviceability but also habitability, which all must be satisfied in increasingly complex wind environments. In fact, even though the performance of tall buildings and long-span bridges affects the safety and comfort of a large number of people, their design continues to be based on analytical and scaled models that have not been widely validated in full-scale.
The seminar will provide an interesting guided tour of the complex dynamic wind-structure interactions experienced by tall building and longspan bridges in turbulent atmospheric winds through the eye of a cyberinfrastructure enabled virtual collaborative platform VORTEX-Winds. It is a virtual organization designed to reduce the toll of extreme winds on society. Quantification of aerodynamic loads on structures is central to the assessment of their performance in extreme winds. The seminar will address fundamental issues related to the modeling of wind load effects on structures, their laboratory simulation and monitoring at full-scale. A general overview of the basic techniques for quantification of wind loads and their effects using analytical, CFD and model-based and data driven simulation schemes, code and standards based procedures, and experimental and full-scale monitoring will be presented. Highlights of an automated shape and topology optimization of structures will also be provided.
Ahsan Kareem is the Robert M. Moran Professor of Civil Engineering and Geological Sciences and the director of the NatHaz Modeling Laboratory at the University of Notre Dame. His research uses computer models and laboratory and full-scale experiments to study the dynamic effects of environmental loads under winds, waves, and earthquakes in order to understand and predict the impact of natural hazards on the constructed environment and to develop mitigation strategies that enhance the performance and safety of structures. He is a former president of the American Association for Wind Engineering. Dr. Kareem is the recipient of the Alan G. Davenport Medal, Robert H. Scanlan Medal and the Jack E. Cermak Medal. He was elected to the National Academy of Engineering, USA in 2009 for his contributions in analyses and designs to account for wind effects on tall buildings, long-span bridges, and other structures. In 2010, he was elected as a Fellow of the Indian National Academy of Engineering and as a distinguished Member of ASCE Dr. Kareem was appointed Honorary Professor of Tongji University, Shanghai, PROC, 2010 and The Hong Kong Polytechnic University in Oct 2012, The Southeast University, PROC in 2013. In 2011, he was inducted to the Offshore Technology Conference Hall of Fame for his paper presented at early years of OTC that offered innovation, direction and lasting impact on the design, construction or installation of offshore infrastructure; in 2012, he was appointed by the State Council of China as a High-End Consultant to Tongji University. In 2013, he received 2013 IASSAR Distinguished Research Award from the International Association for Structural Safety and Reliability. He has served as Chair of the Engineering Mechanics Division and the ExCom of the Structural Engineering Institute of ASCE.