SMG
Mortenson Construction
RISA-3D
Cold-Formed Steel Frames
2013
Pinnacle Bank Arena serves as the foundation for the $344 million West Haymarket Redevelopment Project in Lincoln, NE. The arena regularly hosts concerts, performances and other live events in addition to serving as the home for the University of Nebraska basketball teams. The main structural components of the 470,400 sq. ft. arena consist of a concrete structure, wrapped in metal panel and glass curtain wall façade.
"There is no way we could have done this project without RISA-3D."
— Jeff Kreinke, PE, SE
As a result of various architectural design choices, cold formed steel (CFS) framing encloses the concrete form creating an outer tri-radial elliptical shape. Excel Engineering chose to utilize RISA-3D due to its ease of use and built in cold formed steel design checks. One unique aspect of the frame design was that all gravity load associated with the exterior façade had to terminate at the main concourse level. To accomplish this, special connections utilized vertical slide clips in order to avoid vertical load transfer while allowing the façade to deflect independent from the superstructure.
In total, 96 cold formed steel space frames were designed to handle the changing radius of the elliptical façade while also defining the desired slope of the exterior upper collar. These 50 ft tall by 12 ft wide frames were designed in RISA-3D for special wind loading conditions, additional temporary construction platforms and to be assembled on site in a special jig and lifted into place so that the overall building schedule could be met. In all, nearly a dozen different models were modeled, analyzed and designed in the software in order to capture the various elliptical panel conditions.
Images 1-3: Excel Engineering