Introduction

This guide page is intended as a basic introduction to helical piling in general with a specific focus on our own helical piling system called QuadraPile.

  • Helical piling refers to the installation of helical piles.
  • The term helical piles loosely refers to the group of piles which have at least part of their form in a helical shape.
  • A pile is a structural vertical element of a foundation, either driven or formed in the ground.
  • Helical refers to something taking the shape of a helix which is a 3-dimensional curved form, the most common example in everyday life is probably a coil spring or the thread on a bolt.
  • Helical piles can be helical along their entire length (like the QuadraPile) or helical for only part of their length (like most other types of helical pile).
  • There’s no rule as to what material a helical pile is manufactured from so they can be made from a range of materials: steel, plastic or aluminium alloy (like the QuadraPile) for example.

 

What are Helical Piles Used for?

Helical piles can be used for any number of applications but are often used for:

  • Foundations for traditional buildings (houses, extensions, garden rooms, offices, classrooms, etc)
  • Foundations for modular buildings and extensions
  • Foundations for communication masts (telephone)
  • Foundations for solar arrays / solar panels
  • Foundations for decking or viewing platforms
  • Foundations for ramps & steps
  • Underpinning or repair of existing foundations
  • Repair of failed retaining wall

Helical piles can be used in conjunction with concrete or as a bolt-together solution for concrete-free foundations.

How about 'Screw Piles?'

The terms ‘screw pile’, ‘screw anchor’, ‘ground screw’, ‘helical anchor’ and ‘helical pile’ are often used interchangeably.

Whilst technically the products that these terms refer to differ, in general terms they are all foundations with a part or fully helical shape.

The QuadraPile system is a true helical pile as it is helical along its entire length whereas most other piling systems in this group only have the helical shape for small sections of their length.

How are Helical Piles Installed?

There are two main methods for installing helical piles:

  • Percussion – in simple terms, driving the pile by hitting it. This is usually achieved using an electric, hydraulic or pneumatic driver. This looks similar to a road breaker but is usually higher powered. The pile will rotate as it is driven simply because of its shape. The QuadraPile system is installed in this way using pneumatic post drivers imported from the US.
  • Screwing – driving by applying torque (or rotational force) to the pile. This is usually achieved using a torque head fitted to an excavator or a smaller electric driver (usually with an anchor arm to try to prevent it spinning out of control).


Installation of a QuadraPile helical pile