报告题目: Development of Next Generation Structural Engineering Laboratories
报告人:Tony T.Y. Yang, Ph.D., P.Eng.
Professor, Department of Civil Engineering
Director, Smart Structures Laboratory
University of British Columbia, Vancouver, Canada
Professor, Department of Disaster Mitigation for Structures
Executive Director, International Joint Research Laboratory of Earthquake Engineering,
Tongji University, Shanghai, China
时间:8月26日周一早上9:30
地点:新葡的京集团8814海洋楼208
摘要: The knowledge of earthquake engineering is largely gained through experimental testing. The most direct method to recreate the loading experienced by a structure during an earthquake is via shaking table testing. Conventional shake tables employ linear controllers such as proportional-integral-derivative (PID) or loop shaping to regulate the movement. However, it is difficult to tune a linear controller to achieve accurate and robust tracking of different reference signals under payloads. The challenges are mainly due to the nonlinearity in hydraulic actuator dynamics and specimen behavior. Moreover, tracking a high frequency reference signal using a linear controller tends to cause actuator saturation and instability. In this presentation, a hierarchical control strategy is proposed to develop a high performance shake table. The high-level controller utilizes the Sliding Mode Control (SMC) technique to provide robustness to compensate for model nonlinearity and uncertainties experienced in experimental tests. The performance of the proposed controller is compared with a state-of-the-art loop shaping displacement-based controller. The experimental results show that the proposed hierarchical shake table control system with SMC can provide superior displacement, velocity and acceleration tracking performance and improved robustness against modeling uncertainty and nonlinearities. In addition to shaking table testing, hybrid simulation (HS) is becoming a favorable alternative experimental method to shaking table test. This is particularly useful for the development of novel structural components and systems, where only a small portion of the structure needed to be experimentally tested. Traditionally, HS is displacement-based. Many successful tests have been accomplished. However, such a methodology is not suitable for specimens with high stiffness. In this presentation, a hierarchical displacement-based and force-based control framework for HS is presented. In this framework, a high-level controller generates either the force or displacement commands based on finite element formulation and regulated the force or displacement commend using low-level controller(s). A detailed formulation for the high-level controller is presented.
报告人简历: Prof. Yang is a full professor in the Department of Civil Engineering at the University of British Columbia. He is also the director for the Smart Structures Laboratory at the University of British Columbia and the executive director of the International Joint Research Laboratory of Earthquake Engineering (ILEE). Prof. Yang received his B.Sc. (2001) and M.Sc. (2002) from the University at Buffalo, New York, and his Ph.D. from the University of California, Berkeley in 2006. His research focus on improving the structural performance through advanced analytical simulation and experimental testing. He has developed the next-generation performance-based design guidelines (adopted by the Applied Technology Council, the ATC-58 research team) in the United States; developed advanced experimental testing technologies, such as hybrid simulation and nonlinear control of shake table, to evaluate structural response under extreme loading conditions; developed risk-based simulation models for countries in the North and South America and the Global Earthquake Model (GEM) for the counties in the South East Asia. Prof. Yang’s research has been well applied to national and international research and code committees. He has been invited to over 100 leading research institutes worldwide to present his research. Prof. Yang is one of the 19 voting members of the Standing Committee for Earthquake Design, which is responsible for writing the seismic design provision of the 2020 National Building Code of Canada (NBCC). Prof. Yang is also a corresponding member of the TC9 committee within the American Institute of Steel Construction (AISC), which is responsible for writing the seismic design provision of steel structures in the United States. Prof. Yang is an active member of the Tall Buildings Initiative Project which has developed seismic design guidelines for tall buildings in the West Coast of United States. Prof. Yang’s work has been well recognized by his colleagues, he is the recipient of the 2014 CISC H.A. Krentz Award and the 2011 Kwang-Hua Professor Title from Kwang-Hua Foundation, China.