Mock-Up Work Raises Confidence in Radical Steel Structure

Cutting-edge shear wall core — Team building an 850-ft-tall “proof of concept” for a cutting-edge shear wall core (*above*) made from tied-steel-plate sandwich modules filled with rebar-free concrete is even more confident after building a full-scale mockup (*next photo*) of one level of the core wall.

*PHOTO COURTESY MKA*

Core Wall Rendering — Team building an 850-ft-tall “proof of concept” for a cutting-edge shear wall core (*previous photo*) made from tied-steel-plate sandwich modules filled with rebar-free concrete is even more confident after building a full-scale mockup (*above*) of one level of the core wall.

*RENDERING COURTESY MKA*

The steel sector is so excited about structural engineer Ron Klemencic’s composite steel superstructure, expected to speed office tower construction, that at least three steel fabricators are studying it, many months before erection is set to begin on Seattle’s 850-ft-tall “proof of concept.”

The team gearing up to build the Seattle high-rise, named Rainier Square Tower, predicts the new structure, based on a cutting edge shear-wall core consisting of stacked sandwich modules field-filled with rebar-free concrete, will slash 40% off the time required to build a steel frame surrounding a reinforced concrete core.

“It’s one of the most innovative approaches I’ve seen in my career,” says Peter Labbe, general manager of the Northeast division of Cives.

The steel fabricator is supplying modules for research about to get underway at the University at Buffalo, which is part of a bigger project with Purdue University, to fine-tune the modules. Klemencic, chairman and CEO of Magnusson Klemencic Associates Structural + Civil Engineers, is the engineer for Rainier Square and the organizer of the research, which is funded by $300,000 each from the Charles Pankow Foundation and the American Institute of Steel Construction.

“We feel [the system] has so much merit,” says Don Banker, CEO and owner of Banker Steel Co., who is taking a team to the Pacific Northwest to investigate the system. Herrick Corp. is also excited about the system’s potential to speed office tower construction, says Bob Hazleton, president of the fabricator.

Preparations for Rainier Square’s steel fabrication and erection, including a full-scale mock-up, are proceeding well, according to Adam Jones, president of The Erection Co., which is a subcontractor to the fabricator, the Supreme Group. The mock-up erection work last month “met or exceeded our expectations,” says Jones.

“Completing the mock-up has only reinforced our confidence of a nine-month erection schedule, four to five months shorter than it would take with a concrete core,” he adds. “Our whole team is so tremendously excited about this that I am considering running the project myself.”

The steel sector is not alone in its excitement over the system, which eliminates both reinforcing steel and concrete formwork. “This system represents a paradigm shift, and it will get people’s attention, [especially] after the building is complete,” says Bill Lewis, chairman of Lease Crutcher Lewis, the tower’s general contractor.

Post a comment to this article

We'll invite leaders from this year’s top-ranked firms to talk about the challenges of the year gone by and how they plan to succeed in 2023. We'll discuss the results of the Top 400 survey, as well as moderate a panel of executives from the largest contracting firms as they discuss the industry’s pressing issues, from workforce challenges to data security.