There are numerous ways to utilise screw piles from big industrial buildings to reindeer fences. Yes, you got it right: reindeer fences.
Paalupiste received an interesting job offer to install a 1 800 meter protective fence around a gold mine in Lycksele, Sweden. One of the purposes of the fence was to make sure the reindeers around the area wouldn’t get lost in the mining site.
We developed a brand new product for this project; a mesh fence pile, which turned out to be brilliant.
Technically speaking, the construction of the fence was pretty simple: 3 meter long screw piles were installed into the ground every 3,5 meters so that 2 meters of the piles remained above ground as the fence posts. The mesh was attached into the piles using drill screws and pulled tight.
Installing the mesh into the fence piles is made easy by pre-drilled holes for the screws. The installation took place in January, but the frozen ground did not present a problem and the piles were drilled through the frost without difficulty.
When installing piles into frozen ground, the quality of the screw piles is emphasised, since piles made from weak material won’t be able to withstand drilling into frozen ground. Paalupiste’s screw piles, however, are strong enough for frost installation
Similar mesh fence piles can just as well be used to protect gardens or industrial sites. Our experience is that screw piles are easier to install into hard ground than traditional fence posts. In addition, it is easier to make sure the screw piles are at the right height above ground.
Especially when fencing around large areas, screw piles are an unbeatable method because of the ease and speed of the installation.
We tested the lateral strength of the mesh fence screw piles by performing a tensile test in both sandy and clay soil. A 3 meter long, 60,3 x 2,9 mm screw pile with a 150mm helice mounted to a depth of 1 meter was used in the test. When the pile was pulled sideways from 1,2 meter height, the lateral displacement in clay soil was 10mm with applied tensile load of 160 kg and 40mm with a load of 300kg.
This is enough in most cases, but the lateral strength can be increased further by using a pile with a bigger tube diameter or by using longer piles i.e. installing them deeper into the ground.
Location: Lycksele, Sweden
Type of pile: Paalupiste machine installed PRO™ mesh fence screw piles
Piles used: Approx. 500 piles, pile size 60,3 x 2,9mm with a 150mm helice
Installation machinery: 4,5 tonne excavator with a 4 500 Nm screw pile drive head
Main contractor: Dragon Mining