In 1998, when the world's largest pasta maker, Barilla, started to build its first plant in the United States in Ames, Iowa, rapid construction was essential since Barilla was losing more than $1 million in import costs each month. Key to getting Barilla into production quickly was construction of a 10-story mill that would turn raw durum wheat into flour. Barilla's construction management firm, McClier Corp., chose Evergreen Concrete Inc. to slipform the mill and 15 storage silos. Using a combination of ingenious concrete forming, a large crew, and a lot of work hours Evergreen was able to slipform the mill in only 9 days and the silos in 11 days.
Because the 850-ton slipform on this job was so large, Evergreen had to raise it using 117 jacks and two hydraulic systems, interlinked to operate simultaneously. To speed work, crews precast the concrete floor beams onsite and installed them as the walls were slipped. Removable wood panels made to the width of the precast beams and built into the inside form of the slipform could be removed as the slipform passed the beam locations so workers could set the beams in place.
After crews completed slipforming the walls, they came back and formed, poured, and stripped a floor slab every 5 days. Workers poured the floors from the top down, using suspended flying forms. This enabled Evergreen to cast the floors in about 10 weeks less time than it would have taken to cast them from the bottom up, with shoring.