Big Thickness Slab

An automated storage and retrieval system (AS/RS) is a combination of equipment and computers that allows the owner to store and retrieve materials with precision, accuracy, and speed, according to MHI, the leading association in material handling.

That means that there will very seldom be people inside this 80,000-square-foot, 140-foot-high freezer facility built atop a 2-foot-thick heavily reinforced concrete slab. “We had a specification of FF35/FL 20—so not too difficult to achieve,” says K&M Concrete Construction director of sales and marketing Michael Hoeft. “The big mobile cranes in the warehouse run on tracks, so a high flatness number wasn’t critical.”

The slab is supported by 851 concrete-filled tubular steel piles that were driven to 140 feet deep—that’s almost 23 miles of piles.
K&M Concrete Construction.The slab is supported by 851 concrete-filled tubular steel piles that were driven to 140 feet deep—that’s almost 23 miles of piles.

But what is critical is a solid base. “There was a sub that drove 581 piles,” Hoeft says. “Twenty-three miles of pipe.” The piles are 10 inches in diameter, pointed with a starter cone, driven about 140 feet, and then concrete filled. Then a 2-foot-square by 2-inch-thick steel plate cap was welded on top, which supports the slab. Piles were driven in a grid about every 81/2 feet.