Multiple Bell Ground Anchors
Multiple Bell Ground Anchors Often used in London Clay.
- Uncased, 10 m long 2.0 no/day
- Top Cased type, 15 m long 1.0 no/day
- Anchor Stressing 2.0 no/day
Removable Ground Anchors
Removable Ground Anchors Recent innovation of “removable” ground anchor system. Steel cables are doubles up and threaded over a roller at the anchor end. Once de-stressed, they can be pulled out. 1 rig can achieve…
- Drill 30 m shaft 7.0 hrs
- Install strands/setup anchor 6.0 hrs
- Grout in strands 2.0 hrs
- Stressing can be done 4 – 7 days after grouting.
Usually at 3 m horizontal centres and can only be worked on with 5 – 6 m spacings. So a hit and miss method must be adopted, giving a significant programme constraint.