Flight 93 memorial earns design award
Two local firms had major roles in construction
STOYSTOWN — The Tower of Voices at the Flight 93 National Memorial was recently awarded in the Precast/Prestressed Concrete Institute’s 2020 Design Awards contest.
Two local businesses played major roles in the project: PennStress, a division of MacInnis Group, Roaring Spring, was the precast concrete provider for the project and Leonard S. Fiore of Altoona was the contractor.
Each year, a jury of architects, engineers and precast concrete producers judge construction projects from across North America on creative and innovative uses of precast concrete in a variety of applications.
This year, the Tower of Voices received the Building Information Modeling award.
The 93-foot Tower of Voices houses 40 custom-made aluminum wind chimes. Each chime was cast to produce a distinct musical note, so that together they create a set of 40 “voices” to memorialize the 40 passengers and crew who lost their lives when United Airlines Flight 93 was hijacked by terrorists on Sept. 11, 2001.
Precast concrete was selected for the tower frame because of the precision required to accommodate the shapes of each component and the strength needed to support the tall, slender frame, Paul Murdoch of Paul Murdoch Architects said in a statement. “The customizable nature of precast concrete allowed for a unique design, featuring faceted columns and diagonal, curved beams.”
The tower features a cross section in a “C” shape that allows sound to reflect outwardly from the open side in a fan-shaped pattern. The chimes are suspended at variable heights within the tower, starting from 20 feet above the main plaza and ascending to the top.
The memorial created some construction challenges. The structure lacked a clean geometric starting point due to its curves, and this made form building and checking the pieces extremely difficult, Greg Gorman, senior vice president and chief operating officer for PennStress, said in a statement.
The design also required an extremely high degree of accuracy.
“The use of Building Information Modeling software was imperative to ensuring that the detailed geometry of the pieces was exact, and that no interferences for the reinforcing steel, splice sleeves, lifters, electrical conduit or various other internal components could occur,” Gorman said.