DPI Thruster Excavation Support Shoring (Urgent)
Pipeline expansion through Rocky Mountains
British Columbia


With severe delay penalties on the line for contractors, Arch responded to this failed shoring box system with urgency and pragmatism.

Initial designs of the shoring were appropriate for the geotech and bore-hole data analysis, but unusual cobbles and boulders resulted in severe difficulty for the contractor while installing the sheets.

Solution & Impact

After review of the bridge design details, Arch designed a “push beam” for the excavator and a simple system of hillman rollers and cribbing to slide 4-girder lines across the creek in winter conditions.

The crane was available for assisting the launch, which removed the need for counterweight on the bridge – allowing for a faster launch.