client: Regional Municipality of Hamilton-Wentworth
location: Hamilton, Ontario
project description:
R.V. Anderson was retained to design a 2.44 m ID, 330 m long rock tunnel into the Niagara Escarpment in the City of Hamilton, Ontario. The company began this extensive project by boring through various shale formations with a Tunnel Boring Machine. The primary support consisted of rock bolts and ribbing with a cast in place concrete secondary lining. Two 88 m deep 1.067 m ID shafts, one sewage shaft and one air relief shaft were also constructed as raise bores with precast concrete secondary liners. A 50 mm thick foam layer was installed on the tunnel walls to allow for an anticipated rock convergence of 25 mm during the service life of the facility. The design required special attention to the hydraulic aspects of the 88 m drop. A second shaft was bored 6.0 m from the first shaft to allow air to escape to the top of the shaft. At the bottom of the shafts a cavern was constructed to house an impact cup to disperse the energy of the falling flow. Construction of the shaft liners was made by remote installation, lowering high strength concrete sewer pipes. A compressible cementitous foam grout was used to fill the space between the exterior of the pipe and the rock to allow for anticipated convergence to take place in the rock.
project status:
Project completed for a construction cost of $2,500,000. |
