Excelsior, Minnesota, 2013
As part of the Excelsior Area Improvement project, a 4-foot diameter tunnel was designed to carry a new 24-inch Forcemain under Highway 7. In order to protect the underlying utilities and road infrastructure from settlement during the mining operation, a soil grouting program was implemented by EJM Pipe Services under the direction and supervision of ECO.
The grouting program involved the installation of 5 sleeve pipes above the 185 feet long tunnel trajectory. Each sleeve was injected multiple times with a sodium silicate based grout to consolidate the fine sands around the tunnel trajectory and minimize excessive raveling of the soils during the tunneling operation.
