with Brokk remote-control demolition robots for the concrete removal but needed an efficient solution to shape new concrete on the tunnel’s floor. Due to the tunnel’s radius, the old-fashioned method of screeding with a 2x4 wasn’t an option. Mike Clover, concrete superintendent, was in charge of equipment selection for the project. He searched for a more user-friendly, efficient method to shape the concrete tunnel’s invert. “This project needed equipment that adhered to the tunnel’s shape, while increasing our productivity for the concrete finishing process,” Clover said. “A stock product wasn’t going to cut it. I started doing some research online and stumbled on a picture of a custom drum from a different project that looked similar to what I was looking for.” This project needed equipment that adhered to the tunnel’s shape, while increasing our productivity for the concrete finishing process... “
The Scope of Work PCiRoads, a highway and heavy civil general contractor out of St. Michael, Minnesota, won the bid for the job. The business started in 2008 when a group of experienced construction workers banded together to form a company that uses seasoned crews and innovative technologies. PCiRoads tackles highways, bridges, and specialty projects, taking pride in cultivating lasting customer relationships. The Minneapolis project was the largest job PCiRoads has faced, and Nap Scott, estimator and project manager, knew there would be unique logistics. “This is a major job that’s crucial for the future of Minneapolis’ underground infrastructure,” Scott said. “The amount of concrete involved and the complexity of working far below the streets of downtown made this a standout project.” PCiRoads’ 30-person crew was tasked with installing about 4,200 feet of new tunnel with a total of around 15,000 cubic yards of new concrete. Due to the tunnels lying well beneath downtown Minneapolis, crew members and equipment would need to be lowered by crane down an 80-foot shaft to the worksite. The crew would need to tackle several logistical challenges because of the underground environment, such as dangers from falling rock and close-quarters workspaces. Additionally, new concrete would need to be pumped 1,000 feet into the tunnel, requiring PCiRoads to go through an extensive trial-and-error period to find the optimal concrete slump to pump that far. The scope of the project also included enlarging and repairing the existing tunnel while installing new concrete. PCiRoads was equipped
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