The bright yellow goalposts flanking an interstate highway are not just there to remind visitors that Canton, Ohio, U.S., is home of the Pro Football Hall of Fame. They also are transmission structures, streaming power into the city that birthed America’s professional football league.
The already iconic 80-ft (24-m)-tall goalposts arose during the summer of 2016 in response to a challenge by Hall of Fame planners who wondered if American Electric Power Transmission, POWER Engineers Inc. and Valmont Utility engineers, who were collaborating on a 69-kV rebuild near the gridiron landmark, could build football-themed transmission structures where the conductors would span I-77. The engineers could have punted. Instead, they huddled to create a distinctively playful structure with utilitarian function and commercial possibilities.
The Game Plan Develops
Canton is counting on a nearly US$500 million expansion of its landmark to generate billions of dollars for the local economy over the next two-and-a-half decades. When the new 95-acre (38.5-hectare) Hall of Fame Village opens for the National Football League’s (NFL’s) centennial season in 2019, it will feature a renovated Hall of Fame museum, a new 23,000-seat stadium, a 3000-seat indoor football field, a sports and entertainment complex, and a hotel and conference center. The roster also will include an assisted living facility, a youth sports complex, retail stores and restaurants. With so much in the offing, it is no wonder Hall of Fame officials were seeking clever ways to attract fans to its sports-resort venue.
AEP Transmission, POWER and Valmont started updating and relocating distribution and transmission lines for the village construction as part of AEP’s $7 million rebuild of nearly 4 miles (6.4 km) of 69-kV line in the city. The 45-year-old network had to be modernized to improve service reliability in Canton and, coincidentally, feed the new facilities at the village.
A portion of the rebuild required establishing a new route through Canton’s Stadium Park on the east side of I-77 and then crossing the busy highway near the Hall of Fame campus on the west side of the interstate. To get an easement through the park, POWER and Valmont created an aesthetically pleasing 16-sided green monopole capable of carrying a 69-kV double-circuit line. It was a heftier version of the green fluted poles AEP Transmission used for a 23-kV rebuild elsewhere in Canton. However, everyone thought the structures straddling the interstate, outside the park, would be regular and reliable galvanized single-stem steel poles.
Hall of Fame planners had another idea. They scattergunned emails among project engineers, asking if football-themed towers could be designed to simultaneously satisfy the city’s request for attractive structures, shoulder double-circuit 69-kV conductors and distribution lines across I-77, and serve as quirky, eye-catching tourist bait.
After working a few hours in separate huddles, engineers at POWER and Valmont had a conference call and learned they had been thinking along similar lines. They quickly agreed on a jumbo NFL goalpost with a 44-ft (13.4-m) two-piece goosenecked backbone supporting a 24-ft (7.3-m) horizontal crossbar and a pair of 35-ft (10.7-m) vertical uprights. The arcing stem was a conundrum. Besides shouldering tons of steel, the curve from the vertical pole to the crossbar complicated clearances, loading criteria and attachments for distribution lines, plus raised a concern about torsion.
Clock Ticks Down
AEP Transmission engineers entered the game to study their engineering drawings and specifications. They certified the structures were properly scaled for safe clearances of conductor over the highway as well as strong enough to carry conductor and withstand the rigors of seasons and storms. The connection points for transmission and distribution lines were properly spaced and protected, though oddly placed. The engineers ensured the job, as designed, would meet AEP’s standards for load criteria, materials and building procedures while also meeting the aesthetics AEP’s customer expected.
It was a one-of-a-kind project that had to be done right the first time, as a tight schedule did not allow time for do overs. The tight schedule pointed to a construction deadline of July 30 2016, a week ahead of the Hall of Fame induction ceremonies. As the clock on that deadline ran down, erecting the unique structures in the allotted time was becoming the construction equivalent of kicking a field goal in the final second to win a game.
After pondering the design awhile, Hall of Fame officials signaled their approval to activate the game plan. Engineering plans developed by POWER Engineers and Valmont Utility were sent to Valmont’s steel fabricating plant in Tulsa, Oklahoma, U.S., where the poles and attachments were manufactured. Across Tulsa, American Pipe Bending got the delicate task of curving the upper piece of the main shaft to match the inverted J-shaped stem of an NFL goalpost.
The NFL shared its fluorescent yellow paint specifications for goalposts (Saturn yellow 215-7, made by DayGlo in Cleveland, Ohio). Valmont closely matched the color for powder coating the steel at its plant in Valley, Nebraska, U.S. Full-length padding on each piece of steel kept the paint clean and free of scratches on the journey to northeast Ohio. Everyone wanted to make the goalposts as realistic as possible. With that in mind, Valmont made a shroud to cover protruding connection points on the crossbar and eliminated climbing attachments. The structures were located in an area that would enable easy access for maintenance with bucket trucks.
New River Electrical Corp. assembled the pieces in Canton and created special rigging to lift the gooseneck atop the vertical stem, the two pieces topping 15,000 lb (6804 kg). Crossbars and uprights had to be bolted, centered and leveled precisely. The padding stayed in place until the pieces were ready for placement. The goalposts had to be clean at kickoff. There was definitely a learning curve for all parties involved. The teams noticed the second structure went up faster than the first one.
It Is Up and It Is Good
Pulling the 69-kV conductor and 13.2-kV distribution wires safely across the interstate also was challenging and required a great deal of planning. This period of the activity occurred over three nights and required the cooperation of the Ohio Department of Transportation and Ohio Highway Patrol, which orchestrated rolling roadblocks when New River crews needed to string cables. As it turned out, the supersized goalposts are pretty close to being 100 yards (91 m) apart, the length of a football field.
AEP energized the goalposts on July 29, 2016, a day ahead of the deadline and before crowds swarmed into Canton for the Hall of Fame enshrinement activities. Successful football teams execute the fundamentals, make the most of their resources, challenge their players and stick to a proven game plan. Applying these proven techniques to distribution and transmission projects ensures utilities meet the needs for
reliable power and public safety. In this AEP case, one-of-a-kind transmission structures styled as goalposts provided the added benefit of catching attention and applauding the Pro Football Hall of Fame.
Tony Purses is a designer principal for American Electric Power. In his 43 years of experience in line design, Purses has been part of many innovations and improvements to the AEP transmission system.
Marc Tavares is a senior project engineer for POWER Engineers Inc. He has extensive experience in the utility sector working in a wide range of areas, including distribution engineering, metering services, system strategy, system integration, GIS and transmission line design. As transmission project engineer, he has worked on numerous multiyear transmission projects for American Electric Power.
AEP Scores with Teamwork
Given the compressed construction timeline for erecting the Canton, Ohio, U.S., goalpost transmission structures, there was little room for trial and error. Designing, fabricating and erecting the unique, customized transmission structures necessitated near-daily communications that led to collegial collaborations along with a lot of head-scratching and problem solving among project team members.
Engineers at Valmont Utility, POWER Engineers Inc. and American Electric Power (AEP) built a trusted working partnership that enabled them to think outside the box, concoct solutions and help each other walk through the construction process. POWER developed the engineering specifications, understanding that the goalposts — first and foremost — had to be serviceable and sturdy utility structures that met AEP’s standards for loads and clearances. Although the Pro Football Hall of Fame had not specified a size for the roadside icons, the project team surmised the structures had to be big enough to be noticed, but not garish and extravagant.
Overall dimensions and scale of the new 69-kV steel monopoles were borrowed from structures elsewhere along the route to guide development of specifications for the goalposts. Therefore, the spacing between circuits and between phases on the monopole informed POWER’s engineers of the placement and spacing of those essentials on the uprights and crossbar. The height of the structure also had to allow the required clearance for the distribution circuits installed on the crossbeam.
At the site in Canton, contractor Parks Drilling of Dublin, Ohio, prepared foundations for the goalpost that kept their exposure to a minimum for the sake of authenticity — as a National Football League goalpost shows no foundation — and safety, as the structures would be accessible to the public and an exposed foundation could be a tripping hazard.
After receiving the overall specifications, Valmont fashioned a computer-generated model of the goosenecked two-pronged structure. AEP realized the design had to be altered slightly by widening the spread between the uprights and concurrently increasing the length of the crossbar and scale of the structure. Furthermore, the diameter of the crossbar had to be enlarged to safely accommodate the additional weight of a shroud that was being added to conceal connections on the crossbar. These small changes required another round of consultations with POWER and AEP to verify Valmont’s structural adaptations did not compromise specifications or standards.
With no timeouts remaining when the steel arrived on Monday, July 25, 2016, New River Electrical Corp., the building contractor, got the yellow-coated structures assembled and erected by midweek. With that complete, the project engineers designed and attached plates at the intersection of crossbar and uprights to hold a recently added neutral distribution wire and fiber-optic cable. New River strung all conductors, wires and cables across I-77 at night, finishing on July 29, two days before the final whistle.