Since we introduced screwpiles into Western Australia in 1996 others have introduced numerous versions of screw in foundations to the market. New manufacturers continually come and go as they unsuccessfully attempt to enter the market.
Some think screwpiles are simply a helix welded to a steel tube. Those with that simplistic view use a pile design criteria that at best can only be described as questionable. More often than not one can demonstrate the component specification used in manufacture is insufficient for the intended design load and installation requirements. The typical justification for this practise is to reduce costs and win work.
In our 15 years of design, manufacture and installation we have never compromised on product integrity just to win a job, something we are very proud of.
A typical example of this is where there is a design load requirement of say 50kN for the screwpile, there is a minimum engineering embedment depth requirement and the pile has to be installed through some tough or rocky ground. Engineering design allows for a particular section and wall thickness but in actual fact you could "get away" with a lighter steel section. Then when this pile is installed the installer has difficulties getting to the minimum specified depth due to the installing torques exceeding the sectional capacity. In addition the installer cannot install the pile within the specified eccentricity tollerance resulting in significant pile misalignment causing excessive eccentic loads when loaded. The installed pile is likely fail over design life of the structure.
From time to time we have witnessed screw in foundations being manufacured and installed using second hand steel. It is our opinion that this practise is not in accordance with Australian Standards. See our section on Steel Quality for more important information.
Herein is an example of a steel screw in foundation that has failed. We have not nor will we ever manufacture product that does not perform in accordance with intended engineering outcomes.