Applications

Tapered Steel Light Pole Foundations

The Screwpile Australia Lightpole Foundation System is a simple foundation solution for tapered steel light poles replacing messy slow and expensive concrete bored piles.  Significant time and cost savings are the major advantages.

Screwpile Australia's Steel Screw-in Foundation System is by far the quickest method of installing engineered foundations and allows for immediate lightpole erection as there is no concrete curing time holding up further works. The entire process is reduced to just screwing in a foundation, excavating a small power cable access trench, feeding the power cable through the cable slot provided, lifting up the pole and bolt connecting it to the screwpile, its that easy.

Based on the following information:

  1. Pole height and weight
  2. Allowable bending moment load specified for that pole base (ultimate or SWL)
  3. Allowable horizontal (lateral) shear load (ultimate or SWL)
  4. Pole baseplate and connecting bolt configuration
  5. Site-specific ground conditions and corrosion exposure classification and location

A single screwpile foundation solution is available for monopoles up to 25 metres with a bending moment of up to 150kNm. Multiple configurations are available for mono and lattice towers up to 50 metres regardless of loads. In high wind regions such as cyclonic areas grouped screwpile configurations may be appropriate.

Our lightpole foundation products are hot dipped galvanised for protection against the ambient elements providing for the same design life as . of 35 year design life the same as the ligh pole, however design life can be extended where required.

Important Notes:

Unlike other products, Screwpile Australia’s lightpole screw-in steel foundation system does not use shallow vertical fin plates to transfer the horizontal loads into the ground or to stiffen the piles shaft.  Screwpile Australia’s engineers believe the practice of relying on shallow vertical fins to structurally support the foundation loads is flawed for the following reasons:

  1. It is not known or guaranteed that surface compaction is present or adequate.
  2. Trench excavation next to the pile shaft and fin assemblies is necessary to install the power cable and it cannot be guaranteed that the backfill will be compacted in accordance with the intended design specification.  This is critical as finned foundations are inherently shallow and any loose upper soil zone may result in excessive pole movement under high wind loads.  Possible foundation failure is possible causing larger poles to collapse.
  3. It is common for no site-specific soil density information is available at the lightpole locations and a generic attitude towards pile design is considered dangerous in this instance as there is insufficient overdesign allowing for such senarios. 
  4. Our engineers will not certify the installation of steel screw-in foundations in these circumstances as certification needs to be provided on two components: A) the structural integrity of the product to be installed and, B) the actual installation and subsequent performance of the foundation is in line with the intended engineering design outcome.