Twinning Tunnels
The installation of a deep trunk sanitary sewer system in the bedrock beneath Erin Mills Parkway in Mississauga required an innovative approach for shoring manholes. For this project, HCM was contracted to install nine caisson wall compression rings at various locations. RWH Engineering Inc. (RWH), an HC Group company, provided an economical design for the shafts which had diameters of up to 11 meters and depths up to 50 meters.
RWH overcame several design challenges on this project including the consideration of the compression rings to withstand large uneven surcharges due to a close embankment as well as significant crane loads. To ensure the integrity of the shoring system, RWH provided the precision monitoring services.
This project required the installation of the compression rings into the bedrock to support the overburden. HCM successfully implemented RWH’s innovative design which did not include a bench at the top of the bedrock, as commonly seen in compression ring design. This resulted in a reduced diameter of the compression rings, significantly reducing the amount of bulk excavation required as well as installation time.
The project exemplifies HCM’s ability to find effective solutions to complex projects to minimize construction time.
Location: Mississauga, Ontario
Customer: McNally Construction Inc.
