Leavitt Engineering joined Yanke Energy, Inc., of Boise, Idaho, to complete
structural designs for approximately 640 feet of industrial ducts and
support structures for Roseburg Forest Products' Plywood-1 Facility in
The ducts, ranging in diameter between 30 inches and 60 inches, span up
to 100 feet between supports and are approximately 70 feet above the ground.
Our team also completed structural designs for several duct transition boxes
designed for 5.0 psi internal pressure.
Two of the major support structures were a 50-foot tall steel-framed fan
support tower with stairs and five interconnected space trusses to support
the ducts over an existing building. In addition to the internal pressure,
the ducts were designed to resist all snow, wind, and seismic loads required
by the current International Building Code.