A segmental concrete pile is a type of deep foundation element composed of short, precast concrete segments that are stacked on top of each other and pressed or driven into the ground until they reach a load-bearing soil layer. Each segment is typically 1 to 2 metres long and is connected to the next by a steel coupling or interlocking joint.
Unlike a single-piece driven pile, which is manufactured as one continuous length, the segmental pile is assembled on site segment by segment. This makes it easier to transport and handle, and allows the total pile length to be adjusted to match the actual ground conditions encountered during installation.
Application
Segmental concrete piles are commonly used in residential and light commercial construction where the bearing capacity of the surface soil is insufficient to support a shallow foundation. They are particularly popular in areas with deep layers of soft clay or peat, where piles need to reach firm sand or gravel layers several metres below the surface.
Installation is done with a hydraulic press or a small piling rig. The first segment is positioned vertically, and the machine pushes it into the ground. Once the top of the first segment is near ground level, the next segment is placed on top and the pressing continues. This process repeats until the pile reaches the required depth and resistance.
For DIY builders planning a new-build home or substantial extension, segmental piles are worth considering if a soil investigation reveals poor bearing capacity at shallow depth. They produce less noise and vibration than traditional driven piles, making them suitable for use near existing buildings and in residential neighbourhoods.
A structural engineer will determine the required pile length, diameter, and spacing based on the soil report and the loads from the building above. Typical segment diameters range from 180 mm to 320 mm for residential projects.
Related terms
- Foundation
- Concrete press pile
- Driven pile
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