Helical piers, also commonly known as screw piles and by a number of other names are ground anchoring systems and screw-in steel pilings used for supporting deep foundations. Helical piers are, in essential terms, earth screws that are formed from galvanized steel. They can be used when building a foundation, or as support and repair for pre-existing foundations, and they are turned into the ground until they create stability for both new and existing structures. "Screw pile" is a common name for the foundation aid, as the helical piers consist of two major parts: the screw or helix and the pile shaft.
Screw foundations were first discovered and began being used in the early 1800s as suitable foundations for lighthouses and piers in harbors, largely on the east coast of the United States, built to withstand harsh waves and turbulent winds. In the past, the helical piers were formed from wrought or cast iron. Helical piers were used to help erect over 100 lighthouses along the coast between the 1850s and the 1890s.
Helical piers have become a building staple, extending use from piers, docks, and lighthouses to roads, railroads, and buildings that require fast installation or are to be built close to pre-existing structures. In fact, modern use of helical piers is still in full swing, especially for industrial building.
Helical piers can be turned and installed into the ground in a similar approach you would have with a screw and a plank of wood. Many different earth moving machines may be used to install helical piers including heavy-duty excavators and skid-steer loaders. Correct installation is very important when installing helical piers. In order to achieve best results, calculations, measurements, and installation must be done carefully in order to ensure the foundation is stable and lasting.
There are many benefits to using helical piers. Reduced costs and reduced environmental impact go hand-in-hand when it comes to choosing to install helical piers over other alternatives. Since the devices screw directly into the earth, there is much less soil displacement, reduced soil, and earth transporting costs, less fuel used, which all, in turn, lead to reduced costs and a reduced carbon footprint for the building project.
Determining the number of helicals used, the steel’s thickness and other parameters are dependent on the type of structure being supported, the environment’s corrosion rates, the weight distribution, and the minimum time that the helicals are intended to last at their maximum supporting strength.
Helical piers were an excellent discovery and their use has been expanded over the past 150 years due to their stability, strength, and long-lasting nature. In the future, we are likely to see more use of helical piers, not only saving companies on costs but also helping to conserve the environment.