Retractable Roof and Operable Endzone Wall | Cowboys Stadium | Uni-Systems Projects
Cowboys Stadium
HKS, Inc.
Historic Retractable Roof, Operable Endzone Wall, and Mechanized Video Board
Jerry Jones, owner of the NFL’s Dallas Cowboys, wanted to give fans a stadium unlike any other (and to show that everything in Texas is indeed bigger). With loyalty being a key component to any true Cowboys fan, the team’s new home was designed so that the retractable roof, when open, created a rectangular exposure that looks just like the permanent opening at the Cowboys’ previous home, Texas Stadium.
Uni-Systems was presented with the challenge to design a mechanization system on two rounded arches, the steepest incline the company has worked with yet. Engineers designed a custom rack-and-pinion drive system to ensure the roof’s operation as it climbs the tall arches. The powerful system easily conquers the incline, driving the 800,000-pound roof panels up to their closed positions.
When the roof is opening and traveling down the incline, the motors’ function is actually to slow the roof, allowing gravity to do most of the driving. Using regenerative drives, the power generated through this process is harnessed and input back into the stadium’s power grid.
End Zone Walls
To add to the stadium’s open atmosphere, two operable window walls were installed at each end zone. Clad in glass and offering the stadium unprecedented natural lighting even when closed, these world-record-sized walls offer a stunning panoramic view of the area surrounding the stadium.
The entire system is designed to give Cowboys fans and stadium guests an open-air stadium, but when the intense humidity and heat of north Texas becomes overpowering, the environment can be closed and controlled. Not only do fans remain comfortable, they remain safe. The roof and walls are protected against strong winds through a series of locks and tie-downs designed to keep moving components closed even when the wind may be blowing.
Video Board
Finally, With work on the Cowboys Stadium nearly complete, Jerry Jones and his stadium team were able to marvel at the results of all their work and dedication. With events already scheduled, the new stadium was already a draw for the public. One of the first events that would demonstrate the stadium’s multipurpose aspect was a U2 concert. However, a problem quickly became apparent.
A concert stage used by U2 on their world tour required the stadium’s center-hung scoreboard to be lifted higher to accommodate the massive traveling stage. While a temporary solution was considered, the Cowboys and their design/construction team took it one step further.
Uni-Systems went in immediately to raise the scoreboard for the concert in time, but also installed numerous cable drives to give the stadium ultimate versatility. The scoreboard can now be raised or lowered when necessary from a height of 25 feet to 115 feet above the playing field. The flexibility in the board’s placement allows the operations team to cater to specific events, but keep the display exactly where it was designed to be during football games.
The lifting power comes from several cable drives similar to those used in other Uni-Systems projects. These drives provide raw lifting power to raise or lower the 700-ton scoreboard, while several additional drives maintain tensioned cables that stop the scoreboard from swaying. The entire system is designed to safely and efficiently move the video board while giving the operations crew and event planners the peace of mind they need.
With the video board mechanization in place, Cowboys Stadium stands alone in the world of multipurpose stadiums. Its innovative and impressive features set it apart and make it a truly one-of-a-kind facility.
Retractable Roof, End Zone Walls, and Video Board
General Information
Location: Arlington, Texas, EUA
Scope of Work: Design, Fabricate, Install.
Project Engineer: Justin Waldron
Project Client: Manhattan Construction
Project Team
Architect: HKS, Inc.
Gen. Contractor: Manhattan Construction
Struc. Engineer: Walter P Moore
Retractable Roof
- Two 300x220-foot panels
- Roof opening of 256x410 feet when panels open
- Each panel travels 215 feet
- Panels travel up a 23.9 degree slope
- Each panel driven by 64 7.5 Hp motors within 32 tractors
- Total power for each panel is 480 Hp
- Total towing capacity of each panel is 800,000 pounds
- Regenerative drives put power back into the system when the roof is driven primarily by gravity
End Zone Walls
- Two windows walls, one at each end of the stadium
- Each window wall is 256x120 feet and comprises 7 individual panels, each 38 feet wide and 120 feet tall
- Five of the 7 panels for each window wall are operable
- Wall opening of 180x120 feet when panels open
- Walls open in approximately 5 minutes
- Each panel driven by 2 24-inch diameter steel wheels, each powered by a 3 Hp motor
- Two top guide rollers allow for 20 inches of relative vertical movement between structural steel and concrete below
Video Board
- Entire video board is 160 feet wide and 72 feet tall
- Total weight of video board is 1.4 million pounds
- Lifting/lowering is driven by 16 20-hp cable-drum drives
- 8 10-hp cable-drum drives are used to stabilize the video board from swaying
- Can be placed anywhere from 25 feet to 115 feet above the field (90-foot stroke)
