- Wind Wizard: Alan G. Davenport and the Art of Wind Engineering. by Siobhan Roberts
This is a professional biography of the leading figure in the development of tall towers, buildings, and bridges safely able to withstand the wind. Alan Davenport (1932–2009) was a British engineer who spent his professional career in Canada. He entered the engineering program at the University of Toronto in 1954. The event of the Tacoma Narrows Bridge collapse in 1940 had provided a graphic warning to structural designers about the danger of ignoring the wind, and Davenport was fascinated by the challenge. He pursued a doctorate at Bristol beginning in 1959, and his dissertation explored issues related to turbulence. He used statistical analysis in order to bring order to that untidy field, and he also drew on concepts from meteorology, aeronautical engineering, and structural engineering. In 1961, Davenport accepted a position at the University of Western Ontario, where he remained for his entire career.
Siobhan Roberts organizes the book into three chapters that examine Davenport’s attention to very tall buildings, long bridges, and wind-related natural disasters. Davenport was a pivotal figure in each area. He consulted on many of the tallest buildings erected since 1960, beginning with tests of the design for the original World Trade Center towers in 1964. He contributed to successful designs for (among others) the Sears Tower in Chicago, the CN Tower in Toronto, the notorious John Hancock Center in Boston, the Hong Kong and Shanghai Bank with its trapezoidal aperture [End Page 281] near the top of the structure, and the world’s tallest building, the Burj Khalifa in the United Arab Emirates. Davenport also studied the fabric roofs of the Calgary Saddledome and the Hajj Terminal in Jeddah, Saudi Arabia.
Davenport also consulted on many suspension bridge projects around the world during his career. Bridges truly fascinated him, and they were topics of significant engineering interest after the Tacoma Narrows failure. Roberts examines Davenport’s role on many projects, but it was especially interesting to follow his work over many years to stabilize the Bronx-Whitestone Bridge in New York City. This bridge shared some design features with the Tacoma Narrows, and as a result the Bronx-Whitestone could exhibit unacceptable dynamic behavior. Changes resulting from Davenport’s studies eventually produced a significantly more stable and safer structure. Finally, Davenport’s interest in safe structural designs led to studies of the behavior of any building in the face of tornadoes and hurricanes. He studied electric power line towers, as well as low buildings and houses.
In each chapter, Roberts explores how Davenport studied the performance of structures in the face of wind. Her research rests largely on his papers and numerous interviews. Davenport was not a fluid dynamicist, although he was comfortable with numerical calculations. Instead, he approached wind engineering with two main techniques. First, he applied probability to the wind phenomenon he encountered, enabling him to understand the full range of situations and to design with a sense of real problems. He refined his understanding in unique wind tunnels using scale models of structures that also included topography and local environments. His models of buildings were crucial to his success, for they provided essential information on the dynamic performance of key structural elements. Likewise with bridges, he developed ideal models of the structure but also used detailed models of sections and of full designs. Davenport also monitored the performance of finished structures to compare calculated and real performance. This brief review cannot capture the full range of Davenport’s approaches, but it is worth highlighting that Roberts argues that Davenport’s understandings of the behavior of structures in the wind grew not only from lots of data, but also from understanding the essentials. Thus the book’s subtitle, the art of wind engineering, captures a central feature of Davenport’s approach.
Overall, the book is nicely done and the many illustrations are well-chosen and important. Davenport’s story is worth telling and Roberts tells it well...