McCarthy Building Companies, Inc., the oldest privately held national construction company in the United States, has completed an innovative seismic renovation of the Robert A. Young Federal Building to improve the historic structure’s seismic performance. The 20-story, one million square foot building is one of the largest office buildings in downtown St. Louis, MO.
The U.S. General Services Administration (GSA), which owns and manages the building, undertook this $75 million design-build project to provide additional shelter-in-place opportunities and safe exiting for the building’s 3,000 occupants in the event of an earthquake. Originally constructed in the early 1930s, the Art Deco brick and terra cotta building faces potential seismic hazards because of its location within the New Madrid fault zone.
This project represented the first use of seismic dampers in a St. Louis building retrofit and the GSA’s first time using this alternative approach compared to more traditional seismic renovation methods. This novel strategy eliminated the need for 90% of the concrete shear walls traditionally required, which streamlined the project schedule.
The design-build team’s innovative solution combined viscous dampers, steel braces, and steel sheer walls, enabling all work to be completed while the building was 100% occupied by employees from 48 government agencies. Additional project elements included seismic bracing of non-structural components such as ceilings; partitions; and mechanical, electrical, plumbing and fire protection systems.
“Our McCarthy team worked closely with the designers and trade partners to identify and implement the most flexible, efficient design alternatives and to ensure that all construction work was well-coordinated with office moves,” said McCarthy vice president Ryan Molen.
To complete the project on time and with minimal disruption to government organizations and their employees, construction progressed 21 hours a day — from 6 am to 3 am — with much of the work completed from 6pm to 3 am. McCarthy scheduled and managed customized moves for each tenant. These included either relocating entire offices or temporarily consolidating office work spaces into more compressed areas. After four to six weeks, employees returned to offices that looked exactly like the space they left — including the original location of electric outlets to the exact positioning of each desk.
During the project, water and electric service for tenants was not disrupted, and all work was completed with close attention to environmental considerations, including controlling negative air flow, avoiding potential contamination, noise reduction, odor management, and other best practices.
In recognition of the team’s overall commitment to safety, the AGC of Missouri recognized McCarthy with a Construction Project Safety Award for completing the project without a recordable incident.
The McCarthy-led design-build team includes Gensler (lead designer and architect of record), Etegra (associate architect), and Thornton Tomasetti (structural engineer). Other project team members included William Tao & Associates, Integrated Facility Services, Aschinger Electric, and Wilson’s Structural Steel.