What are Helicast Multi Turn Cast Steel Screw Piles?
Helicast™ screw piles provide superior holding capacity to any other foundation system based on cost, speed of installation and minimal soil disturbance, especially in unstable soils. The Helicast™ screw piles feature a Multi-turn cast steel helical made as a one piece 485 MPa minimum ultimate tensile steel casting. It is possible to found Helicast™ screw piles at substantially shallower depths than that required by conventional driven piles. The versatile cast helix can accommodate a range of shaft wall thicknesses to handle higher installation torques when required to penetrate hard grounds at depth.
The “thread” or multi turn helical on the screw pile allows it to be turned into the ground with impressive speed and accuracy and without the noise and vibration associated with driven piles. Properly selected shaft size in relation to the ground type where foundations are to be installed, will eliminate the need for any costly, time consuming pre-drilling of the piles.
Unstable upper layers, subject to heave and shrinkage, can be avoided by placing the helical assembly deeper than the unstable zone. The lack of major skin friction on the smooth and slender shafts prevents such soil movement from affecting the axial capacity/ stability of the Helicast™ multi turn cast system.
All Helicast™ load calculations are based on end pile capacity with no allowance for additional capacity through skin friction. The buttwelded end attachment of the cast steel helix to the steel pipe shaft allows engineers to use the full structural capacity of the steel pipe, unlike piles which have simple plate helix circumferentially welded around the outer shaft.