As the new Milwaukee Bucks arena reaches 85% completion, take a look inside the structure to see the progress so far. Mike De Sisti
The concrete pad that will chill the ice sheet at the new Milwaukee Bucks arena was poured Friday, a meticulous daylong undertaking guided by GPS and lasers.
The operation also was a delicate timing balance between the curing properties of the concrete with the need to have a perfectly smooth and level surface.
The ice sheet is an oft-overlooked aspect of the $524-million arena, which was designed for NBA and college basketball. The Bucks will operate the facility and are aggressively booking concerts and other events, starting with dates in September.
"We're going to have family ice shows" like Disney on Ice, said Barry Baum, the Bucks senior vice president of communications.
The Bucks also plan to host college hockey games and "an NHL preseason game is a possibility," Baum said. No games have been announced.
One team that won't play in the new arena is the Milwaukee Admirals, which moved from the BMO Harris Bradley Center to the UW-Milwaukee Panther Arena last season. The minor league hockey team moved after it became clear that the Bucks were not including the Admirals in planning for the new arena. The Bradley Center will be demolished once the new area opens.
The ice sheet won't be a permanent part of the new arena, and that's partially why the concrete pour Friday was so important to the project.
A team of arena ice installation specialists from New York led the operation.
RELATED: Admirals move planned
Workers guided a large concrete-gushing hose stretched from trucks in the arena's east loading dock. They directed the wet slop into an 8-inch deep lattice of pipes and structural steel.
The first of several finishing machines spread the concrete to levels adjusted automatically by lasers on the edge of the arena floor. And only a few hours after the initial pour, with the concrete partially cured, another set of machines with fast-moving blades were to zip across and smooth the surface even more.
"You have one shot to put it in and make it perfect, " said Corey Waclawski, a project manager for Mortenson, the construction manager for the arena.
"When they're done, it will look like a normal concrete floor — but there's a lot of stuff inside."
The inner workings of the concrete pad are a carefully engineered system that balances heating and cooling, explained Alex Spangler, a Mortenson project engineer.
First, there's a heating element that prevents the cold from the ice sheet from transferring to and creating permafrost in the ground underneath.
Then there is a layer of stone dust, followed by a bed of insulation. On top of that is the network of cooling piping and structural steel strong enough to support workers and machinery.
RELATED: Miller, Leinies and Coors Light themed bars coming to new Milwaukee Bucks arena
About 45 truckloads of concrete were to be delivered for the project on Friday.
The pour, however, is only the start of the process. The concrete undergoes a temperature-controlled cure for 28 days, a step that's necessary to prevent cracking, Waclawski said.
The chilling system is then activated and the temperature is slowly brought down to the point where it will freeze water. Again, it's a careful process.
"If you cool it too fast, it will crack," Spangler said.
Workers then spray a mist of water over the surface and gradually build up the ice sheet. It's a complicated process for a simple final product — a sheet of ice that's a half- to three-quarters of an inch thick, depending on the use.
The Bucks arena, supported by $250 million in taxpayer funds, is expected to open in late summer.