Workshops: 53W53 | Engineering a Modern Pyramid with Reinforced Concrete Diagrids

Gustavo Oliveira
Vice President | Properties & Building Structures
WSP, New York City

To stand out in the jungle of high-rises and other iconic buildings normally encountered in the urban context of cosmopolitan cities like New York, it takes more than creativity and innovation. It is essential that a close synergy is established between the architectural design intent and the engineering solutions required to enforce the architect’s vision.

53W53 is a luxury condominium building envisioned by Pritzker Prize-winner architect Jean Nouvel for lead developer Hines. Comprising 67,633 square meters, this pyramidally-shaped supertall building reaches 339 meters in height on a narrow 26.5-meter-wide site, resulting in a 1:12 slenderness ratio. Adjacent to the MoMA Museum, the new structure also provides 6,039 square meters of unobstructed gallery spaces at levels 2, 4 and 5 necessitating the implementation of massive steel trusses for load transfer from the limited number of interior columns at the 72 residential floors above. In addition to the structural challenges associated with a slender high-rise, 53W53 implemented a cast-in-place reinforced concrete diagrid structural system for the architectural expression that is also integral to the redundancy and resilience of both, the gravity and lateral-load resisting systems. Perhaps the most challenging aspect was the conception, testing and implementation of highly specialized nodal connections at some diagrid intersections where several structural elements converge from different angles and planes derived on high concentration of stresses and rebar congestion that were mitigated by the utilization of high-strength materials such as, 14-ksi reinforced concrete and Grade-97 rebar.