Trop's top probably can take it, by Georges

The dome can withstand winds of 110 mph, "with a safety factor beyond'' that level, says its designer.

By BRUCE LOWITT

© St. Petersburg Times, published September 25, 1998

t will take a pretty strong storm to blow a hole in the roof of Tropicana Field. The Teflon dome is hurricane-tested to 110 mph, said the head of the company that built it.

More coverage from the Times on our Georges site.

Dave Campbell, chief executive officer of New York-based Geiger Engineering, said a scale-model of the stadium was tested in a special wind tunnel that duplicates the wind on the earth's surface.

The 110-mph threshold was chosen because of the probability of a storm of that intensity hitting once in 50 years, he said.

A storm that exceeds 110 mph over water, however, quickly loses its intensity when it hits land, he said.

But why set the dome's stress limit at 110 mph? Why not 120? Or 150?

"It's based on the statistical analysis of the meteorological record," Campbell said, meaning the likelihood of a storm of a specific intensity sweeping over the dome, how long the sustained winds would last and the average of the wind speed for one minute, as opposed to gusts.

"'We still have a safety factor beyond (110 mph)," Campbell said.

"It's not as though the building is going to implode at 111. You have to set it at something. It should be based on a very unlikely event, and then you have a design margin above that.

"That's how any structure is designed, whether it's for snow or wind, anything. At the end of the day, you could always design for more, but it costs more to build."