In 2017, St. Joseph’s Hospital in Tampa, Florida, broke ground on an expansion project that would bring greater accessibility to patients and become a beautiful new addition to the community. At the core of the project was a six-story tower featuring a beautiful covered entry, 90 new private patient rooms, and a pedestrian bridge to the Women’s Hospital across the street.
When designing the new addition, the architects wanted the organic geometry of the building to reflect the human body while softening the perception of the typical hospital building. They relied on precast concrete to achieve that vision in a durable and cost-effective design.
The addition features a three-dimensional, prefabricated precast concrete skin that “pushes the boundaries between design and manufacturing,” says Noble Levesque, senior project manager for Gate Precast. The defining element of the architecture are the 25-ft-tall precast concrete structural V-shaped columns at the first floor. The design team used precast glass-fiber-reinforced concrete (GFRC) to ensure the columns had the same quality architectural finish as the precast concrete panels above.
The rest of the design includes multiple shapes, including double C-shaped panels, curved panels, a conical base, and parapet panels. “A triangular window with a rounded corner with a deep recess became a signature feature of the entire building,” says Yuri Jukarev, principal of J & M Structural Engineers. “This portion of the building required specific attention during the design stage and resulted in unique design challenges.”
Dimensional control was paramount
The columns did not have sufficent space between the structural concrete and the exterior surface to allow for a cladded option, so the fabricator designed the GFRC as permanent formwork that was set into the forms and cast into the structure. The GFRC permanent formwork allows the structure of the building to be incorporated into the overall building design while providing a high-quality, durable architectural finish.
The corners were especially challenging, Levesque says. To be sure they could meet the exact specifications, the precast team created a mock-up to identify any fit issues and then they measured, remodeled, rebuilt, repoured, and recast the final pieces. “The effort to hold dimensional control was paramount, and the craftsmanship is in full display,” he says.
Bulky parapet panels had to be designed as freestanding elements at the locations where a panel joint was located at the roof level. The three-dimensional level panels along the south elevation also had a significant negative slope and were designed with leaning bearing connections.
Because construction had to be accomplished while the hospital was fully operational, the project required tight coordination of multiple disciplines within confined site restrictions, with access limited to a narrow strip of land. To accommodate these constraints, the structure was erected using a single tower crane shared by the concrete, structural steel, precast concrete, and glass and glazing subcontractors. This resulted in some trade partners working night shifts so the work could continuously flow around the perimeter of the building.
The work progressed in a counterclockwise direction by elevation. It started with the erection of miscellaneous structural steel supports, which were immediately followed by the precast concrete elements and then the glass and glazing units. As each elevation was completed, the precast concrete was punched due to limited accessibility.
The team’s careful collaboration was achieved through daily communication and work plan meetings led by the installing supervisors. This ensured that the project was completed safely without risk to the operational facility or other employees. The project was completed in 2019, and the facility is now providing expanded care to the Tampa community.