Orlando's Orange County Courthouse uses concrete in almost all its variations: cast-in-place, precast, prestressed and post-tensioned. The building's 52 courtrooms required floor-to-floor heights of 16 feet, making the 24-story, 416-foot high-rise almost as tall as a typical 40-story building. Moreover, to provide the unobstructed views required in the courtrooms, floors had to span up to 49 feet. Such large floor-to-floor and column-to-column spacings obviously could result in a less-rigid frame, one more susceptible to the hurricane winds that all buildings in Orlando must be designed to resist.
To compensate for this loss of stiffness and to control differential deflections between floors, a concrete shear-wall design was used. But even the concrete frame required special features to make it stiff enough, including the use of more shear walls than normal, a wide-module concrete-joist framing system, high-strength concrete and post-tensioned beams and girders.
The courthouse tower, two five-story office buildings that flank it, an eight-story 850-car parking garage and a five-story central energy plant are all clad in architectural precast concrete. About 5,400 panels, or 450,000 square feet of precast, were used.