Located on West 57th street, the One 57 Tower is currently the tallest residential building in New York City, at 1,003 feet tall. The project includes a total of 853,076 gross square feet of prime residential units over 19 floors of Park Hyatt Hotel.
The site conditions accommodate the tower footprint in the form of an Lshape, with wings extending toward the east and north. The floor-to-floor heights vary from 10.83 feet to 12.875 feet at the penthouse levels and 23 feet where the swimming pool is located on the 20th floor. The structural system is comprised of a reinforced concrete flat plate system with column spacing up to 30.5 feet. Slab thickness varies from 10 to 12 inches, depending on the floor and span requirements.
In order to minimize the column sizes, high strength concrete of 12,000 psi was used up to the 26th floor.
The lateral wind and seismic for the resisting system consists of shear walls around the elevator cores and stairs as well as wing shear walls to resist the torsional forces. Three concrete belt systems comprised of a one-story perimeter concrete wall at the building’s low, middle and high mechanical levels are utilized to enhance the lateral force resisting performance. The facade setbacks required column transfer systems at several floors.
In addition, a series of transfer girder systems over the amenity floor allowed for the clear space requirement for the pool and other amenities at midheight of the building. Concrete strength of up to 12,000 psi was used with a specified Modulus of Elasticity to enhance the structure’s lateral stiffness.
Separate wind tunnel tests were performed to obtain more accurate wind loads for the structure and facade. In addition, a series of wind tunnel tests were performed to ascertain the building performance for human comfort and serviceability criteria which resulted in the reshaping of the massing and the facade at the upper levels of the building. A stack of four tuned liquid dampers were incorporated on the roof to enhance the building damping’s characteristics, thus improving its performance with respect to human comfort.
The building has two levels underground, reaching down to Manhattan rock. The foundations are spread footings on rock. At the shear walls, tie-down rock anchors were installed to resist the uplifting forces from the wind load.
