Standing strong against the wind
Professor You-Lin Xu is the Dean of the Faculty of Construction and Environment, Director of the Research Centre for Urban Hazards Mitigation, and Chair Professor of Structural Engineering of The Hong Kong Polytechnic University. His research interests include understanding the effects of wind loading and seismic loading on building structures and long span bridges, and health monitoring and damage detection of civil structures.
Xu’s research interest in Structural Wind Engineering began over 30 years ago when he was a Master’s student in the Department of Mathematics in Tongji University in Shanghai, China. Upon finishing his Master’s degree, Xu received a scholarship from the Australian Government as 1 of 22 awardees to pursue a doctoral degree abroad, and consequently, he went to the University of Sydney to study the effect of strong wind on tall buildings.
Back then, Xu’s research subject was a popular but challenging topic. With the economic advances of the time, many tall commercial buildings were being built in populated coastal areas where strong winds and typhoons were a major concern.
Despite the difficulty of the subject, Xu’s persistence helped him push through the challenge and completed the PhD program in 2.5 years. By the time he graduated, he already had published 9 research papers in top international journals.
Xu then moved on to James Cook University in North Queensland – one of the strongest typhoon areas in the region – as a research fellow. However, in his four years in North Queensland, he never got the chance to actually experience a typhoon.
Return to Hong Kong
In 1995, Xu joined The Hong Kong Polytechnic University as an assistant professor. At that time, both the Tsing Ma Bridge and the new Hong Kong International Airport were under construction, so as one of the most active typhoon zones in Southeast Asia, it was important to predict and monitor the effects of strong winds on these large civil structures.
This was particularly important for the Tsing Ma bridge. As the longest suspension bridge carrying both railway and highway at time of completion, the bridge can only swing by a few meters at its mid-span under strong wind, so it was important to install an automated wind and structural monitoring system to sense the wind and structural responses in order to ensure that the bridge can function properly, or else the the bridge has to be closed until the wind subsides.
The chance for Xu to apply his research theory in wind effects and structural health monitoring to practice came soon after he joined the Hong Kong Polytechnic University. The Hong Kong Highway Department invited the Hong Kong Polytechnic University to participate in a collaborative research project on wind and structural health monitoring of the Tsing Ma Bridge.
In retrospect, Xu was thankful for this opportunity because it represented one of the most fruitful collaborations between the Hong Kong Government and academic researchers. He has then used the experienced gained from the Tsing Ma Bridge project and applied it to building the monitoring system for the Stonecutters Bridge – the longest cable-stayed bridge back then, and The Shanghai Centre, the second tallest building in the world. Results from the work were also published in many international papers and 2 books – “Wind Effects on Cable-Stayed Bridges” and “Structural Health Monitoring of Long-span Suspension Bridges”.
Xu has won a few prestigious awards as a result of these important works, including the Croucher Senior Research Fellowship.
“I remember clearly that during the Award Ceremony, Croucher invited Professor Zhou Guangzhao, the President of the Chinese Association for Science and Technology as the presenter, and he was an outstanding scholar. So it was a pleasant surprise and remains a great memory to date,” Xu said. In addition to the award from the Croucher Foundation, Xu also received the Qian Ling Xi Computational Mechanics Award in 2010, and the American Society of Civil Engineering’s Robert Scanlan Medal in 2012 – the first awardee from Hong Kong and second in China.
As the Dean of Faculty of Construction and Environment, Xu is extremely busy with administrative responsibilities for The Hong Kong Polytechnic University. Nevertheless, he still maintains an active research group. His next ambition is to develop smart civil structures – structures that can mimic human beings with self-sensing, self-adaptive, self-diagnostic, self-repairing, and self-powered functions so as to perform any targeted functions in various environments and to preserve the safety and integrity of the structures during strong winds, severe earthquakes, and other extreme events.
Professor You-Lin Xu is the Chair Professor of Structural Engineering of The Hong Kong Polytechnic University. He has conducted research and consultancy work in the field of wind engineering and bridge engineering for almost 30 years, and has published close to 200 research journal papers in wind loading and wind effects on structures, health monitoring and damage detection of structures, structural vibration control and smart structures, and structural analysis and structural dynamics.
To view Xu’s personal Croucher profile, please click here.