Located in downtown St. Petersburg, the Suncoast features a fabric dome that is 688 feet in diameter-the largest cable-supported, clear-span roof in the world, bigger than the Astrodome and nearly every other air-supported fabric stadium roof. Another distinctive feature is its 6 degree tilt, design to reflect the trajectory of a fly ball.

The structure is known as a "cabledome". The system is intended to look like an air-supported structure without the attendant problems and expenses of inflation. The design features a primary structure consisting of a perimeter compression ring beam, concentric tension hoops, diagonal and ridge cables, compression struts and a center tension ring. The compression struts are arranged in concentric rings. The bottom of each ring of struts is connected by a tension hoop. The hoops and struts are "hung" from the tops of the adjacient struts by diagonal cables, which are arranged radially in plan and are bundled with the ridge cables

The suncoast Dome is a four-hoop structure with 140 0.6"diameter strands making up the larges hoop and 40 stands making up the smallest. The diagonal cables vary from four stands at the center tension ring to 52 strands at the outer post.

The outermost set of diagonals connects the largest tension hoop-called "D-hoop" by the engineers- to the perimeter ring beam. The next ring of struts, at "c-hoop" is carried by the diagonal cables from the top of the D-struts to the bottom of the c-struts. The system repeats itself with the hoop elevations increasing to the conter. The innermost diagonals connect the top of A-struts to the lower center tension ring.

Another way to look at the sytem: The ridge cables pull the hoops upward, holding the struts inplace. The ridge cables are actually a cluster of cables, the greatest number of which are at the compression ring-essentially the outer wall of the stadium. As each cable cluster passes over the top of a strut toward the center tension ring, a few cables drop off, thus serving as the diagonal cable cluster that tensions the nexta adjacent hoop.

The structural system allow gravity loads to accumulate in the structure from the center to the perimeter. Thus, unlike a truss system-where the heaviest members are in the center of the span-the cabledome has its heaviest members at the perimeter of the span. The fabric membrane is stressed between the radial ridge cables of the primary structure and the radial valley cables, which in effect hold down the fabric.

Installation of the entire roof, including fabricqation of the fabric pieces was handles by Birdair Inc and required about one year's work with a crew of about 30.

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