The prestigious new Fordham University School of Law and McKeon Residence Hall is the centerpiece of the first phase of Fordham University’s 15-year master plan at its Lincoln Center, New York City campus. The 22-story, 468,000-square-foot LEED Silver-certified building integrates two distinct curved forms, different construction types, and different user groups in one unified complex.
Designed by Henry N. Cobb and Yvonne Szeto of Pei Cobb Freed & Partners, the building forms a new northern boundary to Fordham’s Robert Moses Plaza with three distinct scales, consisting, as the architects put it, of “a one-story dining pavilion opening onto the Plaza’s central green; the nine-story School of Law, whose gently curved surface frames the Plaza; and the taller but quieter slender convex form of the 12-story McKeon Residence Hall, which houses 430 undergraduates.”
The project comprises the 339,000-square-foot School of Law, with 26 classrooms, lecture halls, seminar and conference rooms, a two-story atrium, a moot and trial court facility, and a 90,000-volume law library; the 129,000-square-foot residence hall above, which includes 211 student rooms, five integrated learning center suites, a dance studio, and entertainment rooms; and the 130-seat dining hall. The two main components gracefully interface at the mechanical level, an additional floor that provides the foundation for the residence hall.
“The undulating checkerboard pattern of the precast panels provides a distinct identity for the new law school, while the curved glass curtain wall gives a lighter appearance to the residential tower,” the architects explained. “Yet the two forms meet in a way that reinforces their unity.”
Merging column-free spaces with a residential grid above
The structural engineering team of WSP | Parsons Brinckerhoff responded to the challenges of scale, geometry, volume, budget, and construction schedule with a cost-effective solution that merges column-free public and academic spaces in the law school with the residential grid above.
The law school base structure is a conventional steel-framed building with spans up to 60 feet topped with a 3-inch metal deck and poured-in-place concrete with thicknesses ranging from 3 to 6 inches to ensure conformance with stringent industry Guide 11 vibration and noise criteria. The residential section comprises staggered truss frames with precast concrete panel floors.
The structural engineers developed the solution based on the results of a study of several structural systems designed to stay within the budget while accommodating the need for column-free spans in certain law school spaces: a conventional steel-framed structure with poured-in-place concrete for both the law school and the residential tower; a conventional poured-in-place concrete building for the residence hall; and a staggered truss system with precast concrete floors for the residence hall.
The team settled on utilizing staggered truss frames with precast panel floors within the residence hall because this system is economical and rapidly constructed in buildings with repetitive spaces. This structural solution also reduced the height of the residential component by approximately 10 to 15 feet when compared with a conventional steel-framed building.
Open spaces were maximized in the law school component using moment frames and multistory hangers supported by Vierendeel trusses — open-web trusses with vertical members every 30 feet and rigid joints, but without diagonals — that are designed to support a load of approximately 600k. The lateral system in the law school consists of steel braced frames located along the perimeter and interior moment frames.
Mega columns support the residential tower
The structural engineers were challenged to create a “foundation” at the top of the nine-story academic facility for the residential structure above it because the residential tower columns could not directly continue to the ground. To achieve this, support framing was designed within the mechanical floor consisting of two 24-foot-high curved trusses along the entire 100-foot length of the residence hall, each supported by three built-up steel mega columns that are designed to support loads up to 8,000k.
Sloped columns at the perimeter enable the transition from the law school building to the residential tower. The slab of the residential first level consists of cast-in-place concrete from which are hung the ducts, pipes, and other mechanical equipment. Removable bar-joists were used to support the forms required for this concrete floor as an economical alternative to scaffolding.
Staggered truss system is efficient and economical
The staggered truss system serves as the lateral force resistance system as well as the gravity support system. Lateral forces perpendicular to the staggered trusses are resisted utilizing braced frames. Placed within the partitions between student rooms, the staggered trusses created efficient long spans for the residence hall corridors.
As Pei Cobb Freed & Partners designed the Fordham University School of Law and McKeon Residence Hall to qualify for LEED Silver certification, the structural engineering team incorporated sustainable design criteria, including the use of recycled content and regional materials.
The structural engineering team’s creativity enabled column-free spaces in the law school with a minimal additional cost to the owner. The full-story-height trusses located within the mechanical space created efficient transfer structures for the columns above. Through innovative thinking, the team was able to meld the column spacing criteria from the residential hall above with the column spacing requirements of the law spaces below, while staying within budget and reducing construction time.
Rodica Kestenband, P.E., is vice president, Building Structures, of WSP | Parsons Brinckerhoff (www.wsp-pb.com). She is based in New York City.