Benefits of Screw Piling Include
- Fastest Pile Installation Method Available
- Loads Up To 150 tonne In Some Cases
- Piles Up To 30m Length
- Installation At Any Angle
- Rock Engaging Piles
- Segmented Piles (limited head height)
- No Vibration or Noise (environmental restraints)
- Difficult Access Sites Easily Handled
- Wasteage Eliminated (concrete/soil)
- Massive Reduction In Concrete Quantity Compared to Traditional Methods
- Factory Manufactured Piles For Greater Quality
- Excellent For Sand Soils with High Water Tables
Modern Use of Screw Piles
Screwpile foundations are still used extensively, and their usage has extended from lighthouses to rail, telecommunications, roads, and numerous other industries where fast installation is required, or building work takes place close to existing structures. Most industries use screwpile foundations due to the cost efficiencies and - increasingly - the reduced environmental impact. 'Screwing' the foundations in the ground means that there is less soil displacement so excess soil does not need to be transported from the site, saving on transportation costs and reducing the carbon footprint of the project.
The main benefits of screwpile foundations include: shorter project times, ease of installation, ease of access, reduction of the carbon footprint, ease of removal when the foundations are no longer required, reduced risk to the workforce, and reduced costs. They are also suitable for both tensile and compression loads, so they are also used for masts, signs, and retaining structures.
Installation
A screw-pile comprises a circular hollow section of steel shaft with one or more helical plates welded near to the end of it The size of the shaft (diameter, wall thickness and length), combined with the size and placement of the helical plate are Engineer designed to take full advantage of the available soil capacity. Screw-piles are screwed into the ground similar to a self tapping screw through the use of rotary hydraulics attached to earthmoving equipment. This action results in the compaction of the soil profile to maximize side adhesion and end bearing resistance. Throughout the screw-pile installation the installer monitors the installing torques to ensure that sufficient load capacities are achieved. Changes in soil density are indicated by changes in hydraulic pressure thereby providing important quality control on the load capacity of each pile. The building loads are transferred to the stronger strata below, providing a simple and cost effective deep foundation system as an alternative to traditional methods. Ongoing research, testing and development by Screw-Pile International has established a correlation between installation torque and screw-pile capacity.
