Summarized by Kent Larsen
New LDS Conference Center Construction Detailed in Civil Engineering (A sound assembly)
Civil Engineering Jan00 B1
By Nathan T Charlton, Joseph Collins, James G Peterson, Randall Thomas, and Jeff Huddleston
NEW YORK, NEW YORK -- The architects and engineers behind the LDS
Church's new Conference Center detailed the challenges and methods used
in constructing the building in the current issue of Civil Engineering,
the journal of the American Society of Civil Engineers. In their
article, they make clear the magnitude of the challenges faced because
of the building's size, the size of the auditorium, the building's
depth, the landscaping use of the roof and the LDS Church's requirement
that the building last at least 150 years.
The complex includes 1.5 million square feet, 600,000 of which is in the
auditorium itself. In addition to the auditorium, the complex includes a
900 seat regional theater and a 1,300-car underground parking structure.
The unobstructed views in the auditorium required the designers to
include spans of up to 290 feet in the roof. Because of the rooftop
landscaping, these spans had to support as much as 525 pounds per square
foot. The auditorium's interior walls are more than 100 feet tall and
made of concrete to support the roof.
Because of city ordinances that limit building height to 75 feet above
ground level, the building had to be partially embedded up to 90 feet
below ground level, allowing for both the auditorium and the parking
below it. The size of the building and its placement on the lot kept the
designers from using traditional methods to shore-up the walls of the
building. The exterior walls of the building are as much as 30 inches
wide, and the designers had to use "unique approaches" in the buildings'
foundations and retaining walls. The building's foundation is actually
twice as deep as the parking garage foundation, to support the building.
The LDS Church's desire to have the building last at least 150 years led
the designers to exceed the requirements of the 1994 Uniform Building
Code, which puts Salt Lake City in seismic zone 3. The building can
therefore withstand seismic forces far greater than those required by
The article also notes that the construction of the building required a
number of unusual methods. The trusses that cover the spans in the roof
are usually found in bridge construction and weigh between 215 and 300
tons each. To meet the design requirements, they had to be preassembled
in the shop where they were manufactured, then disassembled and sent to
the site for final assembly. Similar challenges were faced in the 34
cantilevered trusses used to support the balcony.
The design team for the building included architecture firm Zimmer
Gunsul Frasca Partnership of Portland, Oregon and structural engineers
KPFF Consulting Engineers, also of Portland. The construction of the
building was undertaken by Legacy Constructors, a joint venture of three
Salt Lake City construction firms, Okland Construction, Jacobsen
Construction, and Layton Construction.