multiple helical piers

Understanding Helical Piers Systems

Understanding Helical Piers Systems


Helical piers are known by many names, but no matter what you call them, they are often the perfect solution to your traditional foundation issues


multiple helical piers

What Are Helical Piers Systems?


A helical pier is a deep foundation system used to support or resist any load or application. Helical piers are commonly referred to by many names, including helical piles, screw piles, helical anchors, and helical pier systems. A helical pier is a screw-like foundation pin made of steel that contains helices. A hydraulic system is used to drive the helices deep into soil at depths below the frost line.

Today, helical piers are commonly used for residential, light or heavy commercial construction, machinery/equipment foundations, telecommunication towers, tie-downs for wind or seismic forces, and virtually any application where site access is limited or remote.


Advantages of Helical Piers


Screw piles are great for building foundations in common soils, sand, and the most challenging unstable soils. Along with soil versatility, helical piles are often the best option for foundations because they offer many advantages.


Fast and Efficient


Installation of helical piers is unexpectedly quick and easy. Because of their size, helical anchors require no special equipment being brought to the job site. Inclement weather does not prevent installation so that the job can be completed on schedule. Helical piles can be loaded immediately after installation, with no need to wait for concrete to cure. The precision associated with helical piers allows the job to be done exactly as needed, removing the need to make costly fixes once the job is completed. As a pre-engineered system, no time is spent coming up with a solution once you’ve broken ground and can be easily modified if a need arises.


Environmentally Friendly


Helical anchors have the benefit of minimal site damage compared to other types of foundational construction. Screw piles avoid the need for soil cutting, which leaves worksites cleaner and undisturbed. Once installed, helical piers can be left unattended for years and then removed to be reused at other locations. Some environmentally sensitive areas require no construction area vibrations, and because there is no need for large machinery, a screw pile is a perfect solution.


Cost Reductions


Helical piles are so easy to transport and install they significantly reduce construction costs. Because they cause so little disruption to the soil, cleanup and repair times are virtually nonexistent, which results in less workforce hours. Helical pier systems come with almost no maintenance or upkeep, saving your business the costs of aftercare.


Helical Pier Applications


The helical pier is a deep foundation element in its simplest form, transferring a structure’s dead and live loads to competent soil strata deep below grade. This is the same for any deep foundation elements such as driven piles, drilled shafts, grouted tendons, auger-cast piles, and belled piers.

Therefore, helical piers can be used as an alternative method to drilled shafts and driven piles. As is the case with virtually all engineering challenges, more than one solution exists. This decision should consider factors such as load capacity, the existing structure load, and soil conditions.

Helical piles have become the deep foundation solution of choice for walkways and boardwalks in environmentally sensitive areas and expansive soil areas. Helical anchors have several advantages that make them the foundation of choice for many applications, including these general categories:

  • Machinery/equipment foundations
  • Limited-access sites
  • Wind and seismic loading
  • Replacement for drilled/driven piles

Components Of A Helical Pier System


The most effective way to reverse the signs and effects of sinking foundations is to go through an underpinning, piering, or piling process. Several piering systems are available, but the most effective solution is to transfer the weight of a structure to a more stable soil. Screw piles contain helices that serve as end-bearing plates for the weight of a building. The flights are welded to a central steel shaft that acts as a screw, and is rotated into the soil. The helical pier’s simplicity is its greatest asset, allowing its three essential parts to maximize their efficiency.


Helix Bearing Plates


Dies form each steel bearing plate into a true helix. The plates are formed in an actual helical shape to minimize soil disturbance during installation (instead of the inclined plane of an auger, which mixes soil as it excavates). Properly formed helical plates do not measurably disturb the soil. The helical bearing plates transfer the load to the soil bearing stratum deep below the ground surface. “Deep” is considered five-helix diameters vertically below the surface, where the helical plate can develop the full capacity of the plate-to-soil interaction.


Central Shaft


During installation, the central steel shaft transmits torque to the helical plate(s). The shaft transfers the axial load to the helical plate(s) and then to the soil bearing stratum. In addition to having the torsional strength to resist the torque required to install the helical plates into load-bearing soils, the shaft must have the structural capacity to exceed the applied stresses from the building or structure it is supporting.


Termination


The termination connects the structure to the top of the helical pile, transferring the load down the shaft to the helical plate(s) to the bearing soil. To evenly distribute the structure load to the helical anchor, the termination may be a manufactured bracket or an attachment produced on-site as designed by the structural engineer. Intech Anchoring and A.B. Chance design and create specialized termination brackets for a wide variety of loading conditions and applications including, compression, tension, seismic, and lateral types of loading, among others.


You Can Rely On The Expertise of Intech Anchoring


With Intech Anchoring, you can be sure that the equipment and products we recommend are high quality and geared toward the specific goals of your project. Our team offers a same-day response and two locations of inventory to gather supplies. Our experts can be at your side to coordinate your equipment and ensure it is installed according to the appropriate engineering specifications. To learn more about Helical Piers and our support services, contact us today.