Fifteen miles from the Las Vegas Strip, a precast concrete plant in Sloan is producing the more than 1,000 seating risers that will form the backbone of the Athletics’ $2 billion ballpark. Western Pacific Precast began manufacturing the custom pieces three months ago, and the first risers were installed behind home plate earlier this month, said JR Elias, the company’s vice president and general manager.
“We have to start probably two to three months ahead so that the erect never catches the production,” Elias said. The risers, known in the industry as stadia, are cast off-site to avoid clogging the construction zone. They are stored at the plant until flatbed trucks haul them to the stadium at night, with each load carrying one to five pieces depending on size and shape.
The first phase focuses on the main concourse of the upper balcony and part of the outfield, with completion targeted for this fall. “Then we’ll come back on a second phase to allow them to start building out the bottom,” Elias said. “At that time, when we’re done with the first phase, production is still working to get the lower bowl completed with stadia so that we don’t catch them.”
Nearly all of the 1,166 pieces are unique, requiring minor adjustments during installation. Each riser contains a rebar core and is prestressed to withstand the dynamic loads of a cheering crowd. “It’s got to take the pressure of all the people on there,” Elias said. “Then when they’re cheering on the A’s, doing wave and bouncing up and down, there’s a frequency that they’ve got to meet.”
Installation of each piece takes 20 minutes to an hour, depending on alignment. Tolerances range from a quarter-inch to three-eighths of an inch. The stadium’s design also includes air-conditioning vents beneath most seats — a feature not present at Allegiant Stadium, which Western Pacific also supplied.
Western Pacific’s portfolio includes Allegiant Stadium, Sphere, T-Mobile Arena, Lee’s Family Forum, the Intuit Dome, and other major venues. The same construction manager, the Mortenson-McCarthy joint venture, oversaw Allegiant Stadium. “They know our work, we know how they work; so it makes the communication a lot better,” Elias said.
During summer heat, crews work overnight from 10 p.m. to 6 a.m., switching to daytime hours in the fall. About 60 workers are at the Sloan plant and a dozen at the stadium site.
