CN RAIL / SHOTCRETE AND GROUT CONSTRUCTION / BRITISH COLUMBIA
Project Overview
The Bulkley Canyon Retaining Wall project in New Hazelton, British Columbia involved construction of one of three retaining walls for a CN Rail siding between Mile 36 and Mile 42 on the Bulkley Subdivision. The system consisted of a reinforced shotcrete wall tied back with pressure-grouted double corrosion-protected soil anchors (DCP anchors).
Project Scope
MSI constructed access ramps and a shotcrete-supported access corridor, including temporary retaining structures and fall protection measures along the steep canyon slope. Injection bore anchors (IBO bars) and a shotcrete retaining wall were installed to support drilling equipment used for the main anchor system.
6-inch boreholes were drilled using cased drilling methods, and DCP anchors were installed and pressure grouted to 100 psi. Anchors were tested after achieving required grout strength, with grout socks used to maintain bond and capacity where required.
A reinforced shotcrete wall was constructed against falsework over a continuous spread footing, encapsulating the anchor system in 8-inch lifts. Once strength requirements were met, the wall was backfilled, anchor heads were installed, and anchors were locked off at design load to complete the structure.
Project Highlights
- Construction of retaining wall system for CN Rail Bulkley Sub siding expansion
- Reinforced shotcrete wall tied back with double corrosion-protected soil anchors (DCP anchors)
- Complex canyon-side work with engineered fall protection and access ramp systems
- Installation of temporary shotcrete support walls for drill rig access and stability
- 6-inch cased borehole drilling and pressure grouting to 100 psi
- Use of grout socks to ensure anchor bond and performance requirements
- Anchors load-tested after 7-day strength gain and locked off at design loads
- Full-height reinforced shotcrete wall constructed in 8-inch lifts over continuous footing
