A patented proprietary ground improvement system that comprises a series of piers constructed of uniformly graded aggregate (or stone) installed using specialist equipment.

The piers are installed vertically in the ground in either a triangular or square grid to at least 4m depth below the ground surface. A layer of compacted gravel is then put over the top of the piers, ready for the construction of a structure.



A technique that compacts granular soils and rearrange the soil particulars into a denser state. The compaction is attained using depth vibrators, typically suspended from a crane or mounted on piling equipment.

How do Rammed Aggregate Piers improve the ground?

Rammed Aggregate Piers help to limit the amount and consequences of liquefaction by:
• Displacing soil laterally to densify the soil and increase soil stiffness
• Reinforcing the soil creating a stiff composite soil mass

By achieving this, the non-liquefying soil crust is thickened and stiffened to reduce the likelihood of undulations, tilt and uneven ground surface subsidence from liquefaction of the underlying soil layers.

How are Rammed Aggregate Piers constructed?

Rammed Aggregate Piers are installed by experienced contractors, using specialist equipment involving an excavator with a vibrating mandrel attachment. An excavator or tele handler continually loads stone into the hopper, feeding it down the mandrel and into the ground. The stone is compacted using a ramming and vibrating action to form a stiff, high-density, vertical aggregate pier within the ground.

An advantage of Rammed Aggregate Piers
is that no dewatering or excavation is required
for construction. They also typically have a
short construction period.

What soils suit Rammed Aggregate Piers?

Rammed Aggregate Piers are best suited to sandy soils. A greater concentration of Rammed Aggregate Piers are required when used in siltier soils. Because of the large equipment required and the requirement for an area to store the stone, this method may not be practical for smaller properties or those with limited access.
With a team of experienced management and staff
we are available to provide the right solutioN 
to your geotechnical problem

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