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TWA Maintenance Hangar
Mi c ro - Conc rete Mode l Tes t
WJE was retained to design, construct, and test a scale model of the thin, folded plate roof structure proposed for the TWA Maintenance Hangar
in Kansas City, Missouri. The roof structure design was comprised of intersecting hyperbolic paraboloids of reinforced and post-tensioned concrete.
The main shell of the scale model was only 0.3 inches thick. Within it were two layers of reinforcement and post-tensioning tendons. After a series of
concentrated load tests, uniform loading was applied to the model using differential air pressures created by producing a partial vacuum in the space
beneath the model.
The unusual geometry of the roof structure and the size and complexity of the micro-concrete scale model presented enormous technical
challenges that WJE engineers and technicians had to overcome in building and testing a scale model of this unique structure. This project was
probably the last great scale model test conducted by WJE—the dawn of the computer age brought with it the ability to analyze most complex
structural shapes using finite element programs.
Notes of Interest
• Testing of this model would not have been possible
without the 20,000 square foot expansion of WJE’s home
office and laboratory in the early 1970s.
• The maintenance structures—with their innovative folded
plate roofs—are still used today by American Airlines,
which acquired TWA in 2000.
WJE 50 Years