User:Yrtim/Olivier pile

An Olivier pile is an underground deep foundation pile made of concrete or reinforced concrete with a screw-shaped shaft.

History
The Belgian Gerdi Vankeirsbilck applied for the production patent for the Olivier pile in April 1996. This technique was implemented by his company Olivier Betonfabriek en Funderingstechnieken. Since then, 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 and loam. In 2017 a patent was obtained for drilling without the use of a lost bit.

Description
An Olivier pile is drilled into the ground by the use of a steel drive pipe with at the bottom a cylindrical augar head with a helicoidal flange and a 'lost bit' underneath. The steel driving pipe has an external diameter of 324mm (12.75"), with a wall thickness of 25mm (1"). The steel driving pipe consists of several parts assembled with watertight couplings, which are strong enough to handle the maximum torque produced by the rotary head. The various augar heads, for the various diameters of the Olivier Pile, all have a larger diameter than the steel drive pipe.

Common diameters of the augar head:


 * diameter 36-56cm (14"-22") max 60 ton
 * diameter 41-61cm (16"-24") max 80 ton
 * diameter 46-66cm (18"- 26") max 100 ton
 * diameter 51-71cm (20"-28") max 120 ton

Implementation



 * 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 rotary head with a maximum torque of 55 ton meter is pulled up and down along an adjustable leader, wich 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 through the steel drive pipe.
 * Then the auger head is screwed back. The lost tip is disconnected from de augar 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 steel drive pipe. 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 steel driving pipe and the auger head are back on the ground.

External link

 * Implementation for pile foundations, wtcb.be
 * Cast piles, floridabuildingofficials.com