Owing to space limitations (see the March, 2002, Architectural Record for the full story), we were unable to include all the technical information that makes the Kimmel Center singular. Below is an elaboration of certain points. Plus see a complete list of the people and products.
— Suzanne Stephens

I. Barrel Vault
The Kimmel Center’s basic structure is a steel frame on a concrete foundation. Steel columns, vertically cantilevered, support the barrel vault’s folded plate arched Vierendeel trusses that span the 174-foot atrium. The arches were constructed of two types of rectangular steel tubes: one, (in the direction of the arch) is 5 by 5 inches. The other, (in the direction of the folded plate) is 4 by 5 inches. The laminated glass panels in the roof are approximately 7 by 3 feet in size.

Click images for larger view.

The entire assembly is held in place by a cable system suspended from a single arch under the roof, which is vertically separated from the roof so that the arch and the cable structure are structurally independent. As Viñoly puts it, "A very dead pattern of cable produces uniform load on the arch. The arch takes in compression what you would take in bending—like a sail." Between the arch and the vault a neoprene pad is installed, which slides vertically and horizontally to accommodate extra movement. The thin linear cables are attached to the corners of the glass panels. To prevent the cable system from lifting under wind pressure, weights were installed at the bottom of the cable. Each weight is consistent in profile, but they weigh different amounts.

III. Verizon Hall’s Wood Exterior and Interior
Verizon Hall’s exterior comprises 1522 prefabricated panels of plain-sliced Makore (African Cherry) wood from Ghana with a cathedral-shaped grain. According to Rick Herskovitz of Architectural Woodwork Industries, this species was chosen since it would be less likely to fade from the sunlight entering the atrium. On the exterior of the 95-foot-high wall, linear fins project 7 inches at the top, receding to 2 inches at the middle. At the bottom the back panel moves out so that the "fins" transmute into 2-inch-deep reveals.

On the interior of the auditorium, quartered-figured African mahogany veneer was used instead of Makore, since it has more luster and reflects well under low light. On the walls of the auditorium, the 1/2-inch-thick fire-rated panels with mahogany on both sides, 705 in all, are applied to fire-rated plywood with a continuous urethane bond, which was glued continuously to the 10 inch-thick solid-grouted cement block walls.

To disperse the sound at various frequencies and in multiple directions, Viñoly and the acoustical consultant, Russell Johnson of Artec, installed battens, trim, and bumpy wood of South American mahogany on the walls and on the undersides of the balconies. Six different patterns of wood are used for the bumpy wood areas, which have semi-open pores. The balcony rails, which are tilted upward to reflect sound, are formed of 206 curved sections, with a fire-rated plywood inner frame, cork reveals, and finished with mahogany panels, cappings, and soffits.

The swinging panel doors, surfaced with the solid blocks of bumpy wood, are constructed on a 3-inch steel tube frame, with three layers of high-density fire-rated board, and four layers of high-density gypsum board on the backs. Neoprene seals prevent sound leaking when the doors are shut. These swinging panels open into reverberation chambers, 71 feet high and approximately 16 feet deep, which line the auditorium on both sides of the room.

Mahogany lines the ceiling of the auditorium as well: 1456 fire-rated mahogany curved panels, 3/8 inch thick, have been applied to 3 inches of plaster or high density drywall with a continuous urethane glue bond to prevent any loss of sound. The plaster itself is placed on a lath and embedded with wood strips to add to the mass and make it more reflective. Architectural Woodwork and Russell Johnson and Chris Storch of Artec say they developed this method of filling the plaster and block wall voids and attaching the wood with adhesive covering as "extreme" measures to make sure that the sound would be contained and reflected.

Over the stage are suspended three large movable canopies, covered with the same 3/8-inch ceiling panels and partially with open-grained cork. The stage itself is 77 feet wide and 45 feet deep which can be extended to a 52–foot depth. The stage floor is stained beech with a six-inch airspace on resilient pads.

Computer modeling was employed by the design team and the woodworkers to create the sizes and alignments for the many complex forms in the auditorium. First, three-dimensional modeling was used to develop templates for the concrete slabs, ceiling shapes and door placement. Next, the shapes and definition of each panel and component were developed to make sure the prefabricated elements would fit precisely into the space in the short amount of construction time allowed. —S.S.

Continue with Technical Tidbits: The A\coustics

See the the People & Products behind this project