An Olivier pile is a drilled displacement pile:. This is an underground

deep foundation A deep foundation is a type of foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does to a subsurface layer or a range of depths. A pile or piling is a vertical structural eleme ...

pile made of

concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wi ...

reinforced concrete Reinforced concrete (RC), also called reinforced cement concrete (RCC) and ferroconcrete, is a composite material in which concrete's relatively low tensile strength and ductility are compensated for by the inclusion of reinforcement having hig ...

with a screw-shaped shaft ( helical shaft) which is performed without soil removal.

History

The Belgian Gerdi Vankeirsbilck applied for the production

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...

for the Olivier pile in April 1996. This technique was implemented by his own company and various licences have been granted in Belgium and abroad. Due to its screw-shaped shaft, the Olivier pile is particularly suitable for use in soils with low load-bearing capacities, such as

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...

and

loam Loam (in geology and soil science) is soil composed mostly of sand (particle size > ), silt (particle size > ), and a smaller amount of clay (particle size < ). By weight, its mineral composition is about 40–40–20% concentration of sand–sil ...

. In 2018 a patent was applied for drilling without the use of a lost bit.

Description

An Olivier pile is drilled into the ground by the use of

drilling rig A drilling rig is an integrated system that drills wells, such as oil or water wells, or holes for piling and other construction purposes, into the earth's subsurface. Drilling rigs can be massive structures housing equipment used to drill wat ...

with a top-type rotary drive with variable rate of penetration. A lost tip is attached to a partial-flight

auger Auger may refer to: Engineering * Wood auger, a drill for making holes in wood (or in the ground) ** Auger bit, a drill bit * Auger conveyor, a device for moving material by means of a rotating helical flighting * Auger (platform), the world's f ...

which, in turn, is attached to a casing. The casing, which is rotated clockwise continuously, penetrates into the ground by the action of a torque and a vertical force. At the desired installation depth, the lost tip is released, and the reinforcing cage is inserted into the casing. Concrete is then placed inside the casing through a

funnel A funnel is a tube or pipe that is wide at the top and narrow at the bottom, used for guiding liquid or powder into a small opening. Funnels are usually made of stainless steel, aluminium, glass, or plastic. The material used in its construct ...

. The casing and the partialflight auger are extracted by counter-clockwise rotation. The shaft of the Olivier pile has the shape of a screw. The casing has an external diameter of 324mm (12.75"), with a wall thickness of 25mm (1"). The casing consists of several parts assembled with watertight couplings, which are strong enough to handle the maximum torque produced by the rotary drive. The various auger heads, for the various diameters of the Olivier Pile, all have a larger diameter than the casing. Common diameters of the auger head * diameter 36–56 cm (14"-22") * diameter 41–61 cm (16"-24") * diameter 46–66 cm (18"- 26") * diameter 51–71 cm (20"-28") * diameter 56–76 cm (22"-30")

Installation

* An Olivier Pile is screwed into the ground without vibration, the soil is displaced sideways. No soil is transported to the surface. * The rotary pressure is compared with the results of the

cone penetration test The cone penetration or cone penetrometer test (CPT) is a method used to determine the geotechnical engineering properties of soils and delineating soil stratigraphy. It was initially developed in the 1950s at the Dutch Laboratory for Soil Mecha ...

. * The rotary head with a maximum

torque In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of th ...

of 55 ton meter is pulled up and down along an adjustable leader, which is strong enough to hold all the forces. The leader is adjustable in all directions, so that it is possible to drill leaning backward or forward. * When the desired depth has been reached, it is possible to place

reinforcement In behavioral psychology, reinforcement is a consequence applied that will strengthen an organism's future behavior whenever that behavior is preceded by a specific antecedent stimulus. This strengthening effect may be measured as a higher freq ...

through the casing. * Then the auger head is screwed back. The lost tip is disconnected from the auger head and left behind. During the screwback process, the soil is displaced again. This system is called 'double soil displacement'. * While screwing back, concrete is poured into the casing. Because of the weight of the concrete, the concrete is injected into the space under the auger head. During the screwing back, the Olivier Pile is formed with the screw-shaped shaft. The screw-shape has a pitch of ±250mm (±10") and an external diameter of ±200mm (±8") larger than the base shaft. This process continues until the entire casing and the auger head are back on the ground.

External links

Research and Development Activities on Pile Foundations in Europe
wtcb.be
Drilled Displacement Piles – Current Practice and Design
researchgate.net
Cast piles
floridabuildingofficials.com
The history of displacement piles
soilmecna.com

References

{{Reflist Geotechnical engineering Civil engineering Foundations (buildings and structures)

History

Description

Installation

External links

See also

References