- Soil anchor length
- 6 m
- Anchor hole diameter
- 100 mm
- Support systems: soil anchors, and bolts, screen and shotcrete
- 2
The Work
Shoring and ground support for an apartment building excavation in the city — grouted soil anchors where the walls are soil, and bolts, screen and shotcrete where they are rock.
The excavation for a new apartment building on Joseph Howe Drive cuts through two kinds of ground. On one side it is soil all the way to the bottom of the dig. On another, bedrock starts about eight feet down and climbs from there. Each needed its own kind of support, and neither could be allowed to move toward the street or the houses beside the lot.
The soil walls are held with grouted soil anchors: 6 metres long, drilled at 100 mm and fully grouted on hollow bars, as the engineer specified. Grout is mixed on site and pumped into each hole.
The rock walls are bolted and screened, with the screen pinned tight to the face, then covered in shotcrete. These are the same methods our underground crews use in portals and headings, applied on a city lot.
Stock photos: Joseph Howe Drive — Excavation Support — photo by Raimond Spekking, CC BY-SA 4.0.
Next Project
Caribou Mine — Tailings Dam Raise
New spillways cut into rock beside a tailings dam and its concrete spillway — 30 blasts under a 25 mm/s limit at the dam, every one independently monitored, the highest reading 37% of the limit.