Burnhamthorpe Water Project C1&C2
Role: General Contractor
Project Delivery: Design-Bid-Build
Tunnel Equipment: 2ea 1.2m MTBMs, 3m & 2.7m TBMs (Shielded), 3m TBM (Main Beam), 800mm MTBM
Primary Support: Microtunnelling Pipe, Ribs & Lagging, CPP Carrier Pipe
Ground Conditions: Georgian Bay Shale Formation
The project included approximately 2200 meters of 1200mm sanitary sewer and 210 meters of 600mm watermain installed my microtunneling. The 1200mm sanitary sewer was installed using a single passed method with RCJP directly installed. The 600mm watermain was installed inside a 1500mm diameter jacked microtunnel CPP with an inside steel liner. The sanitary sewer works required the construction of 6 shafts, each 7.14m diameter, varying in depth from 24m to 30m.
The project also consisted of 3.6km of 3m diameter Tunnel in shale (800m using rockbolts & mesh and 2,8km using ribs & lagging), with a 1500mm carrier CPP being installed within the excavation. The watermain works required the construction of 6 shafts with a diameter of 14.1m with varying depths ranging from 22m to 29m.
The sanitary sewer was excavated using a 1.5m diameter slurry MTBM and the watermain tunnel was excavated utilizing a 3m main beam TBM and a 3m diameter single shielded mixed faced TBM.
All shafts were constructed by ribs/wire mesh/shotcrete in the overburden and rockbolts and plywood in the shale, with the exception of 3 shafts constructed using secant piles for overburden support.
Drive Length: 3600m, 400m & 200m
Diameter: 3m, 1.5m & 1.5m
Contract Amount: $134,071,727
All tunnel drives were within the Georgian Bay formation shale with limestone layers reaching strengths up to 230 MPa.