Cross-Border Connections: Guideline Documents, Codes, and Standards for wind

Canada and the US have been leaders in developing the field of wind engineering. In the US one can go back to the collapse of Tacoma Narrows Bridge in 1940 as a triggering event for much of the early research by F.B Farquharson, von-Karman and others during the 1940's and 1950's into bridge aerodynamics. Later, in the 1960's J. Cermak and his co-workers at Colorado State University undertook pioneering work in developing accurate simulations of the natural wind within the planetary boundary layer. Almost in parallel, in Canada, at the University of Western Ontario techniques were being developed by A.G. Davenport and co-workers for measuring the complex wind loading patterns on buildings, and for studying the dynamic response of large structures such as tall buildings (e.g. the original World Trade Centre towers of New York) and bridges. Cermak was very instrumental in having wind runnel testing methods recognized in wind codes and standards and in developing wind loading provisions in the US. In Canada Davenport was equally active in developing the wind provisions for the National Building Code of Canada. As the 1970's progressed the knowledge of wind effects on buildings was greatly advanced by both Cermak's and Davenport's teams. Also other institutes in Canada such as the National Research Council of Canada, the University of British Columbia, the University of Toronto and Concordia in Montreal became active in the field of wind engineering research and consultation as well as several others such as MIT, Texas Tech and Johns Hopkins in the US. R. Scanlan pioneered advanced methods for analyzing bridge flutter in the US at Princeton and Johns Hopkins Universities. In the early 1970's the first purely private consulting firm in wind engineering was formed in Guelph, Ontario, Canada. It built its own wind tunnels and eventually became known as RWDI (short for Rowan Williams Davies and Irwin Inc.). Also in the US in the early 1980's the private firm of CCP, short for Cermak Peterka Peterson Inc., was formed by members of the group at Colorado State University to provide wind engineering services similar to RWDI's. By the 1990's the field of wind engineering had grown substantially and besides the major research programs going on at Universities such as Texas Tech, Colorado State, Western Ontario, and Concordia, wind tunnel testing of large buildings, stadiums and bridges had become routine at the private wind tunnel testing houses such as RWDI and CPP. All of this activity meant that there was considerable world leading expertise present on both sides of the border and the competition between the various test houses led to an acceleration in the range of wind engineering services provided and techniques used. It also led to numerous collaborative efforts in the development of various wind codes and standards, which this paper will now briefly summarise.