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Vortrag: Prof. Qingshan Yang

Lecture: Prof. Qingshan Yang

Extreme Wind Speed Distribution in A Mixed Wind Climate, Monday, November 25, 2019, 13:00

Summary

The meteorological services of mid-latitude countries record wind speeds averaged over 10 min or 1 h periods and peak wind speeds for the same averaging period or a full day. Design wind speeds based on the statistical analysis of this data in a mixed wind climate may prove to be imprecise and unsafe due to the occurrence of intense, small and rapid extreme wind events such as thunderstorm outflows. And a reasonable extreme wind speed analysis cannot be done without separating the data related to different phenomena. Thanks to the continuous high-frequency records registered in Beijing, China and the ports in the northern Mediterranean Sea, the data gathered during different intense wind events were separated into selective homogeneous datasets by a semi-automatic procedure. Herein, considering two port areas, a preliminary but representative analysis of the extreme wind speed distribution has been carried out over a 6-year period. Firstly, independent extreme wind speeds are selected based on the time interval that separates successive extremes. Then, the extreme distribution of the peak wind speed for each wind phenomenon is given by the Type I extreme value model. Finally, the information on the extreme distribution of the peak wind speed is completed by mixed statistics and by gathering the ensemble of all the extreme values into a single set. At least in the seaport areas examined here, the results show that wind events with a high return period, the most important for structural safety, are always related to thunderstorm phenomena. The mixed extreme distribution asymptotically overlaps with that for thunderstorms for high return periods and always provides the highest wind speeds. Gathering the ensemble of all extreme values into a single set leads to underestimating of the extreme wind speed. The refined analysis based on the data of Beijing is still in process.

 

Brief Biodata

Qingshan Yang (1968- ) is distinguished professor and dean of School of Civil Engineering at Chongqing University, director of Beijing’s Key Laboratory of Structural Wind Engineering and Urban Wind Environment. He was awarded Changjiang Scholar Distinguished Professor of Chinese Ministry of Education. He serves as the Vice-Chair of Wind Engineering Committee of Chinese Civil Engineering Society. His research interests include structural wind engineering, earthquake engineering, and structural health monitoring. He has been sponsored by numerous fundamental research funding, such as the National Natural Science Foundation of China (NSFC) for Major Program, State Key Program, and Distinguished Young Scholars Program.

He is currently the host of two ‘111’ programs titled “Innovation and Intelligence-importing base on Mitigating Wind-induced Disaster of Infrastructures Sensitive to Wind” and “High Performance Infrastructures and Effective Operation of Wind Farms” sponsored by Chinese Ministry of Education and State Administration of Foreign Experts Affairs. He has published more than 150 SCI-indexed journal papers and has finished more than 40 practical engineering programs including the wind tunnel tests, engineering consulting of sports stadiums (Birds Nest) for 2008 Beijing Olympic Games, airport terminals and tall buildings, and performance maintenance of Cultural Heritages such as the Potala Palace in Tibet. He drafted the Chinese National Code of Wind Resistant Design of Roof Structure. Given his tremendous contributions to structural wind engineering, he won the State Science and Technology Awards in 2018. He has co-chaired the 15th International Conference on Wind Engineering (ICWE15) during September 1-6 2019, Beijing.

 

Prof. Dr. Qingshan Yang

School of Civil Engineering
Chongqing University (CQU), Chongqing, China