An MV pile is a steel foundation pile that is driven into the ground while cement grout is injected along the shaft through an internal duct. MV stands for Müller Verpress, after the German company that developed the system. The grout lubricates the pile as it goes in and, once set, forms a rough sleeve that locks the pile to the surrounding soil.
How it works
The pile itself is usually a steel H-section, a sheet pile section or a tube. At the toe sits a widened base plate or injection shoe. During driving, cement grout flows continuously out of the toe and up along the shaft:
- While driving, the grout acts as a lubricant, so driving resistance and vibration are reduced
- After setting, the grout bonds to both the steel and the soil, greatly increasing shaft friction
Because the capacity comes largely from that shaft friction, the pile is as suitable for tension as for compression — the feature that sets it apart from most ordinary driven piles.
Applications
- Heavy tension loads — anchoring quay walls, sheet pile walls and excavation support systems
- Underwater concrete slabs — as a tension element resisting uplift from groundwater
- Alternating loads — bridge and lock foundations that see compression and tension in turn
- Raked piles — MV piles can be installed at an angle, which anchor arrangements often require
Points to watch
- Installation is specialist geotechnical work: grout pressure and volume must be monitored and logged
- The system is not an economical house foundation; the extra cost is only justified by high tension or compression loads
- Capacity is verified through load testing or from cone penetration test data, not from driving formulae alone
- Where the grout does not fully enclose the shaft, a corrosion allowance on the steel thickness is required
Related terms
- Pile foundation
- Tension pile
- Grout injection
- Sheet piling
- Cone penetration test
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