Mole Constructors, Inc. performed the first Precast Segment Tunnel in North America when we excavated 3.3 km of 2.16 m diameter sanitary trunk sewer in the city of Thunder Bay, Ontario. The tunnel was constructed through soft clay soil with boulders.
The 2.47 m diameter Earth Pressure Balance Machine excavated the tunnel while erecting the precast segmented lining consisting of four trapezoidal-shaped segments 11 cm thick and 1 m long.
The tunnel was constructed in a deltaic plain with grey silty clay with unconfined compression strengths of 15 to 32 Kpa.
Project Details
- Owner: City of Thunder Bay
- Location: Thunder Bay, Ontario, Canada
- Performed as: Mole Constructors, Inc.
- Project value: $31,500,000.00
- Completion Date: May 1979