报告题目：Damage assessment and form-finding concept of natural draught cooling towers
报 告 人：Professor Noh, Sam-Young
报告时间：2026年4月23日（周四）上午8:30
报告地点：谭山书院博雅讲堂
报告摘要：Natural draught cooling towers are important thermal power plant components for an efficient and resource-preserving production of electric energy. Cooling towers grow in size with increasing plant capacities and efficiency. Because of the giant size and slenderness of these structures they are extremely sensitive to dynamic excitation by turbulent wind flow. The formation of cracks in the reinforced concrete shell due to gales and temperature loads may considerably devaluate the predetermined lifetime of cooling towers since the repair is difficult and thus the cost is extremely high. Therefore, the preservation of their structural reliability for the predetermined life-time becomes an important issue: The most economical way to this must be to design cooling towers under the consideration of the durability. Natural draught cooling towers often develop visible crack structures as consequences of progressive damage processes over their life time. The features of these damage processes are the wide frequency range of the dominant excitation, the occurrence of a shift of the structural response spectrum towards higher spectral ordinates parallel to the degrading structural stiffness and also a damage-controlled self-adaptation phenomenon. The Lecture demonstrates numerically such progressive damage process in reinforced concrete structures as a prerequisite for improving their durability and extending their life time. An existing natural draught cooling tower with a pronounced crack pattern was chosen for a numerical example. The numerical simulation deals with a typical damage state of large cooling towers. As second issue, the lecture shows a form-finding concept of a hyperbolic shell which is the most important process in the natural draught cooling tower design. The result of the previous work leads to the idea that the inner area of the hyperbolic shell generator should be minimized for the cooling tower with higher first natural frequency. Three representative cooling towers were selected for the analysis of the structural behavior by means of nonlinear finite element method and evaluated using a damage indicator based on the change of natural frequencies. The results show that the damage behaviour of the cooling tower reinforced heavily due to a lower first natural frequency is not necessarily advantageous than the other two.
报告人简介：Professor Noh, Sam-Young is a faculty member in the Department of Architecture and Architectural Engineering at Hanyang University, South Korea. He earned his Ph.D. in Structural Engineering from RWTH Aachen University in 2001, following a Dipl.-Ing. from Dortmund University (1993) and a Bachelor’s degree from Hanyang University (1986). His academic career spans over two decades, including roles as a Visiting Scholar at the U.S. National Institute of Standards and Technology (2011–2012) and research positions at the Institute for Statics & Dynamics at RWTH Aachen and Bochum University (2000–2003; 1995–2000). His expertise lies in structural mechanics, nonlinear finite element analysis (FEM), and the numerical modeling of complex structural materials. His pioneering research focuses on the theory and failure mechanisms of shell structures, as well as simulating structural collapse under extreme conditions. His work has significantly influenced both academic research and industry practices, solidifying his reputation as a leader in structural engineering innovation.
