The roof wheels are housed in structures called
bogies. The bogies are situated between the roof
truss and a large crane rail. At 100 pounds per foot
and 1,750 total feet of rail length, the operable roof
sits on the second-largest crane rail in the world.
The single panel design also affects the weight
distribution across the roof panels. To balance the
substantial weight of the roof, there are more wheels
and a complex suspension system to carry the
weight from the roof to the rails and throughout the
entire 1.7-million-square-foot structure.
"That's also what's unique about this one. Instead of
a two-wheel bogie, we have a six-wheeled bogie,"
Agosto explained.
Every bogie features six 6,000-pound wheels, four
more wheels than the average retractable roof
system. Half the wheels are motorized with 10
horsepower motors, giving the roof a total of 600
horsepower.
Moving about 39 feet every minute, the roof will
open in an estimated 15 minutes.
COMMAND CENTER:
As it comes time to open or close the retractable
roof, the action requires only the push of a single
button. Located in the command center, the roof
operator has access to control the actions of the
260,000-square-foot roof.
Uni-Systems also designed the computer
mechanism and programming for roof operation.
The computer checks for faults in the system before
allowing the roof to start operation.
The operator must keep his or her hand on the
button the entire time the roof is in transit, and as
soon as the finger comes off the bottom, the roof is
programmed to automatically stop.
"It operates similar to how your phone senses your
finger touch. If your finger leaves the switch, the
movement will stop," Agosto said.
The operator can track where the roof is located at
By the Numbers:
Roof Size: 268,800 square feet
Travel Distance: 405 feet
all aspects of operation. The roof is equipped with a
variety of tracking devices, allowing the computer to
know exactly where the roof is located at all times.
The main operator also connects with several spotters
placed along the roof rail. The spotters travel next to
the roof rail to watch out for obstacles or any possible
problems with the mechanism. The same process is in
place when the roof is closing.
"The spotters are not only making sure there's nothing
in the way, but also monitoring that the roof is
moving the way it should be so it's not getting out of
alignment," Manhattan Vice President of Operations
Jim Cuddihee said. "They're also making sure the roof
is moving at the pace it should be. It's more like a
safety measure."
ROOF PROGRESS:
Since June, work on the 5.5-acre retractable roof has
been moving at a rapid pace. The first retractable roof
truss, weighing 3.3 million pounds, was installed and
relocated down the rail in mid-July.
One retractable roof truss section is being installed
every week, and three sections complete an entire
truss. There is a total of five retractable roof sections
to complete the 24-million-pound structure, with
conclusion of the steel roof structure expected to
conclude in October.
The roof construction involves more than the
track and steel. As soon as one truss is completed,
construction will begin on the decking, tying all five of
the panels together.
"We'll construct one truss, then slide it over on the
rail to start the roof deck and the ETFE framing,"
Cuddihee said. "As everything is tied together, we'll
start working on the bulb seals, what keeps the rain
out from the retractable to fixed roof."
ETFE panels, the transparent material that will help
natural light flow throughout the building, will be
installed alongside the steel work. Retractable roof
construction is expected to be complete by the end of
the fall.
Travel Speed: 39 feet/minute
Estimated Time to Open: 12-15 minutes
Operable Roof Weight: 24 million pounds
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