What is sheet piling?
Sheet piling can be made of a several different materials such as concrete, steel, plastic and wood. It often acts as a temporary supportive wall driven into earth to provide support for soft soils and help avoid soil collapse from higher ground.
They are often used in environmental applications such as:
- Tunnels
- Locks and dams
- Waterfront structures
- Piled foundations
- Excavations and trenches
- Slope stabilization
- Flood protection.
Sheet piling can be constructed using one of three driving methods.
1) Pitch and Drive – loose soils and short piles.
Pitch and drive is the simplest method for sheet pile driving, it involves driving each sheet pile to full depth before pitching the next one. However it is only suitable for loose soils and short piles.
2) Panel Driving – dense sands and hard cohesive soil.
The purpose of using panel driving is to ensure that the sheet piles are driven with good alignment and verticality. The risks of driving difficulties and problems of de-clutching also can be minimised. As a whole panel of piles is pitched there is no need to drive all piles fully to maintain piling operations. If obstructions are encountered, individual piles can be left high without fear of disruption to the overall efficiency. Panel driving is suitable for dense sands and hard soils.
3) Staggered Driving – dense sand, gravel or rock.
In difficult soil conditions, panel installation combined with staggered driving is more suitable in driving process. The piles are installed between guide frames and then driven in short steps as follows: piles 1, 3 and 5 first; then piles 2 and 4. If the soil is very dense sand, gravel or rock, piles 1, 3 and 5 can be reinforced at the toe. In this case, these piles are always driven first and piles 2 and 4 in the second stage.