This lecture presents a rational procedure for the seismic analysis of underground tunnels using recorded free-field earthquakes based on the 2.5D finite/infinite element approach. The near and far fields of the half space are modeled by finite and infinite elements, respectively. Using the 1D wave theory, the nodal force and displacement on the near-field boundary are computed for each spectral frequency of the earthquake. Then, equivalent seismic forces are computed for the near-field boundary for the imposition of earthquake spectrum. By assuming the soil-tunnel system to be uniform along the tunnel axis, the 2.5D approach adopted can duly account for the wave transmission along the tunnel axis, which reduces to the 2D case for infinite transmission velocity. The horizontal and vertical components of the 1999 Chi-Chi Earthquake (TCU068) are adopted as the free-field motions in the numerical analysis. The maximal stresses and distribution patterns of the tunnel section under the P- and SV-waves are thoroughly studied by the 2.5D and 2D approaches, which should prove useful to the design of underground tunnels. Comments on the idea to extend the present approach to include the effect of overlying water, such as the case for the sites below reservoirs, rivers, or sea, will also be pointed out.
Professor Yeong-Bin Yang got his Ph.D. degree from Cornell University in 1984. Previously, he was President of National Yunlin University of Science and Technology (YunTech), Dean of College of Engineering, NTU, Chairman of Civil Engineering Department, NTU, President of Asian-Pacific Association of Computational Mechanics (APACM), and Chairman of East Asia-Pacific Conference on Structural Engineering and Construction (EASEC).
He was the founding President of Association of Computational Mechanics Taiwan, and the President of: Institute of Engineering Education Taiwan, Chinese Institute of Civil and Hydraulic Engineering, Society of Theoretical and Applied Mechanics, and Chinese Society of Structural Engineering. He has received a number of Awards, including (1) Zienkiewicz Medal, APACM (2022), (2) Li-Guo-Hao Bridge Innovation Medal, Tongji University, China (2022), (3) Nishino Medal, EASEC (2016), (4) Tsuboi Award, IASS (2008), (5) Munro Prize, Engineering Structures (2003), (6) Outstanding Scientist, Nobel Laureate Dr. Y. T. Lee’s Foundation, Taiwan (1998), (7) Distinguished Research Award, National Science Council, Taiwan (1988-1998), etc. In addition, he has published 4 books, 280 SCI papers, with a citation number of 14,666 and h-index of 60.
Clean water and clean air are vital for public health. This project focuses on developing high-efficiency and environmentally sustainable filters for removing harmful air/water pollutants. The team has developed novel architectures and functionalities for the filters to achieve high permeance, high removal efficiency, and excellent reusability.
