Workers prepare support column rebar below the sky bridge at Tacoma General Hospital. Photo courtesy of J.R. Abbott Construction

The project was a seismic retrofit and upgrade of the J-Wing birthing/intensive care units, as well as a seismic upgrade of the sky bridge that crosses from J-Wing to L-Wing.

The $930,000 job consisted of constructing three concrete shear walls in occupied patient rooms of the ICU unit, with tie-in to the structure of the cancer ward above. While the actual patient rooms themselves were vacated during construction, all the surrounding areas were occupied and functional.

The concrete shear walls were a challenge because the job required concrete to be pumped into an occupied ICU — without using any interior stairways or chases. The solution was to remove exterior windows and pump the concrete up four floors.

Epoxy column wraps were installed on three existing concrete columns spanning two floors. In addition, eight 30-inch-diameter columns, extending 50 feet below street level, were installed to support two 75-foot-long wide-flange beams. The beams in turn supported the under side of the sky bridge.

Negative air machines were used during the epoxy curing stage to exhaust the fumes. Care was taken to coordinate the location of the exhaust so as to not re-introduce the odors into adjacent air intakes.

The project’s greatest challenge was penetrating the occupied space below street level to build three auger-cast columns. Drilling had to be coordinated during off-shift hours. In addition, intense water control methods had to be used to insure that there was no disruption to the hospital’s activities below the work.

Construction personnel received critical training in hospital procedures and protocol in order to ensure the safety of patients, hospital staff and fellow workers.

The project was originally intended to span six months. It was finished 45 days early with no injuries or recorded accidents.