June 20, 2023 - 11:00am to 1:00pm

The Structural Engineers Association of Illinois is pleased to announce the Tall Building Design Seminar. David Tayabji, Greg Thompson, and John Kilpatrick share their presentations on tall building design and the challenges this art can pose.

Attendees will receive 2 hours of CE credit.

320 South Canal (BMO Tower): Chicago’s First Use of 80ksi Steel

-David Tayabji

320 South Canal is a 50-story, 1.3-million-ft² office building with 300,000 ft² of additional structured parking. The project features 9 tower columns on the east and west façade that transfer to 3 columns with a two-story transfer truss sitting atop “bi-dent” columns. The structural steel transfer truss creates a column-free lobby with 40-foot-tall ceilings. The project features Chicago's first use of ArcelorMittal’s HISTAR®/ASTM A913 Grade 80 structural steel sections. The V-shaped “bi-dent” columns seen at the tower base were fabricated using “Web Tailor Made” (WTM) steel in Grade 65. The massive steel columns are highlighted as unique architectural elements and create a dramatic lobby space.

Wind Tunnel Testing for Buildings – A Practical Review

-Greg Thompson and John Kilpatrick

As the complexity of buildings grows, designers may have reservations about the applicability of code-based methods for design. The measurement of wind loads on buildings can be carried out with a high degree of accuracy in boundary layer wind tunnels, and when incorporated properly into the design these data will lead to more efficient and economical outcomes. Topics related to the prediction of wind loads are examined in this presentation including (i) the provisions of the ASCE 7 standard, (ii) a review of the wind tunnel testing and analysis process, (iii) comparisons of full-scale responses with wind tunnel predictions, and (iv) application of the wind tunnel technique to novel façade and structural systems. A brief overview of the Prestandard for Performance-Based Wind Design developed by the Structural Engineering Institute (SEI) of the American Society of Civil Engineers (ASCE) will also be provided.


Members: $60

Nonmembers: $90

This will be a virtual event on Zoom. Attendees will be required to have a free Zoom account in order to have access to the presentations.

Meet the Speakers

David Tayabji, PE, SE

Senior Associate, Magnusson Klemencic Associates

David is a structural engineer focused on the design of office developments ranging from high-rise office buildings in urban environments to low-rise campuses. He has had the opportunity to apply his expertise across the U.S. including high wind and seismic regions


Greg Thompson


As one of our senior project managers, Greg has overseen complex, multidisciplinary projects in locations around the world--from Toronto, Canada to the Middle East to Hong Kong and to the Mongolian desert. RWDI clients benefit from Greg’s unwavering focus on client satisfaction and from his international experience, which enables him to ably navigate the regional and cultural nuances of projects in diverse settings. Greg’s mechanical engineering background combined with his strong communication and project management skills make him a valued member of any project team.

John Kilpatrick


John manages RWDI’s global wind engineering team as well as the firm’s technical development in this area. During his over two decades in the field, John has earned a reputation as a creative and insightful wind engineer who delivers substantial value for clients by meeting complex challenges in building design. Working closely with design teams to develop a thorough understanding of wind effects on specific sites and structures--especially high-rise buildings, stadia and flexible structures--John has developed technically sound and cost-effective solutions for projects around the world. Among other professional distinctions, John has been a recipient of the State-of-the-Art in Civil Engineering Award, presented by the American Society of Civil Engineers.




Tim Corcoran ( Thatcher Foundations )
Navid Naraghi ( The Consulting Engineers Group )
Thomas Zalewski ( Strang )
Rachel Jackson ( Thornton Tomasetti, Inc. )
Joseph Dardis ( ArcelorMittal )
Richard Weber ( Wiss, Janney, Elstner Associates, Inc. )
Joseph Petrich ( Sargent & Lundy LLC (Retired) )
David Weihing ( ESD )
Sudarshan Krishnan ( University of Illinois School of Architecture )
Juan Carlos Esquivel ( JCE Structural Engineering Group, Inc. )
Devon Telberg ( Envision Architects )
Conner Maines ( Krieger, Maines and Vicars Consulting Engineers, LLC )