Your Guide to Helical Pile Terminology

Your Guide to Helical Pile Terminology

The helical pile world can be technical and confusing. With decades of experience in the industry, we’re happy to help simplify it a bit.

If helical piles are a new concept for you or you’re looking for more information before you can fully decide if they’re the right solution for you, you’re in the right place. This is a glossary-style blog post full of all the most important helical pile terms you should know.

15 Key Helical Pile Terms You Need to Know

Every day, more and more information is published about helical piles and how they function to make great foundations. But it can be difficult to fully grasp their capabilities if you don’t understand some of the technical terminology.

Here are 15 of those terms related to helical piles, helical pile design, and helical pile installation — broken down into clear definitions by our experts.

1. Helical Pile

A helical pile is a segment that makes up a larger, deeper foundational system. It consists of a central shaft, and at least one helical plate welded onto it. The plate’s axis is positioned parallel to the shaft’s length — making it look similar to a screw.

Helical piles are also commonly referred to as: helical piers, helical anchors, helical foundations, screw piles, and screw anchors.

2. Helical Plate

A helical plate is one component of a helical pile. It’s a helix-shaped blade that’s welded onto the central shaft of a helical pile section. When embedded into soil, the helical plate helps to support compressive and tensile loads, and they’re spaced in a way that minimizes soil disturbance during installation.

Helical plates are also commonly referred to as helical blades and helical bearing plates.

3. Lead Section

A lead section is the first section of a helical pile. It’s the first to make contact with soil and always has at least one helical plate.

Lead sections can vary in length depending on project needs but are usually between 5-20 feet.

4. Helical Extension

A helical extension is a square bar or round shaft section that connects onto the helical lead section. It’s needed to form a continuous length of steel so the pile can reach its intended depth.

Helical extensions are most often smooth sections, but can also have helical plates welded onto them in certain situations — usually when you’re dealing with very soft soil.

5. Pitch

Pitch is the distance between one helical plate and another along the central shaft. It’s critical that the pitch is uniform to ensure minimal soil disturbance during installation and optimal performance post-installation.

6. Torque

Torque is the force applied to a helical pile (usually by a gear motor) that causes the pile to rotate and embed itself into the soil. It’s an important measurement to calculate before the installation process.

7. Tensile Load

Tensile load is the force pulling at a helical pile, often causing the pile to lengthen or pull out. Examples of forces that produce tension loads include wind, soil, water buoyancy, frost, and earthquakes.

Tensile load is also commonly referred to as tension load.

8. Compression

Compression is the force pushing on a helical pile, often causing the pile to shorten or settle deeper into the soil. It’s the opposite of tensile load.

9. Lateral Load

Lateral load is the force that pushes or pulls on a helical pile in a direction that’s perpendicular to the longitudinal axis of the pile.

10. Down Drag

Down drag is a circumstance where soft soils around a helical pile consolidate and pull downward, causing the pile to settle deeper into the ground. Down drag can occur due to the weight of soil, changes in groundwater or other additional loads put on the ground surface.

11. Corrosion

Corrosion is any force of nature that corrodes the helical pile metal and weakens its performance over time. Although it’s an extremely slow process, it is an important factor to consider when looking at your project’s soil conditions and environment.

12. Soil Resistivity Rating

A soil resistivity rating determines the rate at which a helical pile will corrode. It considers things like soil conditions, environmental conditions, the thickness of steel, and any corrosion protection measures that have been taken.

13. Slide

A slide is a device that attaches to the boom of an excavator. It’s used to stabilize and control the forward and backward movements of a torque motor during the helical pile installation process.

14. KIP

Acronym for Kilo-pounds. Helical pile engineers often specify in KIPS while designing helical piles and referring to the loads they can support. 1 KIP = 1,000 pounds.

15. OSHA

Acronym for the Occupational Safety and Health Administration. OSHA has established many health and safety regulations that apply to helical pile installation — the most prominent being OSHA 1926.6603.

Elite Helical is dedicated to ensuring safe helical pile installation practices, so we maintain strict adherence to OSHA standards.

Do You Have a Helical Pile Project in Mind? Contact Us!

The helical piling industry can get technical. At Elite Helical, we’re here to make it easier on you by providing safe, high-quality solutions, and keeping you informed every step of the way. If you have questions on helical piles, the installation process, or if we’re the right choice for you, contact us today.

5 Tips for a Safe Helical Pile Installation

5 Tips for a Safe Helical Pile Installation

Helical piles offer incredibly safe and strong foundational solutions. When compared to traditional concrete foundations, they offer more structural support, instant load-bearing capacity, and extended life expectancy — but that’s only if they’re installed correctly.

The helical pile installation process is a fairly quick and simple one, but it still requires expert service and close attention to detail. If anything is installed incorrectly, it could compromise the viability and, most importantly, the safety of the project

Here are some things we do at Elite Helical to ensure a safe and secure helical pile installation.

5 Tips for a Safe Helical Pile Installation

Ensuring a safe helical pile installation project starts long before the installation actually takes place. In fact, for us, much of how we set our team up for success is done before we even get to the project site.

Here are our top five helical pile installation safety tips, straight from our experts.

1. Calculate the Correct Helical Pile Load Capacity

It’s important to know exactly how much weight helical piles can support. Knowing this information prior to installation helps ensure that the piles are installed in the correct amount, lengths, and depths. Otherwise, they won’t be able to bear the necessary load and support the structure.

There are three primary ways to determine helical pile load capacity:

  • Torque correlation
  • Bearing capacity in soil
  • Direct capacity measurement

At Elite Helical, we always use at least two out of these three methods to calculate helical pile capacity. This way, we can get a more accurate gauge and ensure a stronger, more durable, and safer foundation.

2. Schedule Full-Team Trainings on OSHA Regulations

The Occupational Safety and Health Administration (OSHA) has established many health and safety regulations that are applicable to helical pile installation. The most prominent is OSHA 1926.6603, which dictates various standards to comply with while using pile driving equipment. It’s under the umbrella of OSHA 1926, the Safety and Health Regulations for Construction.

However, there are many other applicable OSHA standards that aren’t specific to helical pile installation. Think things like:

  • Noise control
  • Personal protective equipment
  • First aid and medical attention
  • Environmental controls (gases, fumes dusts, etc.)
  • Sanitation
  • And more

In order to ensure that our workers are safe while completing helical pile installations, we hold regular staff training sessions on OSHA regulations. Whether we’re reviewing and refreshing on material we’ve already learned or going over a new standard, we’re always up to date on these standards — and we know the importance of adhering to them at all times while out on a job.

3. Prepare for High-Risk Projects & Environments Ahead of Time

If you fail to plan, you are planning to fail. That’s why our team thoroughly investigates all aspects of a project before we get to the site and start working. This is especially important for projects and environments we’ve deemed “high-risk” for one reason or another.

For example, helical piling is a great foundational choice for structures in remote or limited-access locations. This could be onshore or offshore. Either way, we inform ourselves of the area we’re headed before we go there, so we understand the conditions we’re working with and can plan for what to do in the case of an emergency.

4. Conduct Daily Pre-Task Safety Assessments

Every morning, our team completes a pre-task safety analysis form. This needs to be completed before we can begin any work on a project.

The pre-task safety analysis form runs our team through a series of questions to ensure that we’re safe and equipped for work, the conditions around us are safe to work in, and that we’re in compliance with OSHA and other applicable industry standards. It’s a great daily check-in that helps us be proactive and notice any potential safety hazards before they occur.

5. Re-Evaluate Tasks & Processes Regularly

Once we complete a task or job, we’ll evaluate how it went. We’ll ask ourselves questions like:

  • What went well? What didn’t?
  • Were there any hiccups in the installation process? Why?
  • Were there any times we didn’t feel safe?
  • Were there any processes that could have been improved for efficiency?
  • Were there any processes that felt too rushed?

And so on. Overall, these evaluations are completed in order to continuously improve human and environmental safety during the helical pile installation process. And it’s part of what’s got us to being one of the safest, most efficient companies in our industry.

For Safe & Effective Helical Pile Installation, Choose Elite Helical.

At Elite Helical, we make safety a top priority — for our people and for our environment. We’ll work with you to ensure helical piles are installed quickly and in a responsible manner that protects everyone involved.

For more information on our helical pile installation process and what it’s like working with us, contact our team online.

Are Helical Piles Environmentally Friendly?

Are Helical Piles Environmentally Friendly?

The construction industry has a large footprint and heavy footfall when it comes to environmental impact. But more than ever, reducing that impact is a necessary consideration for industrial and commercial construction for social, ecological, and economic reasons. This reckoning comes with an exploration of alternatives to traditional methods; in the foundations space, this means helical piles.

Helical piles offer some distinct environmental benefits over conventional foundations, including recyclable materials with a lower emissions profile, reduced soil displacement, and increased durability—all of which are also distinct financial benefits, and reflected in the relatively low cost of helical pile foundations. There are also some exciting applications for helical pile foundations in renewable energy infrastructure.

Helical Piles Are Made from Recyclable Materials

Helical piles are generally made of steel. The current process for manufacturing steel does emit a significant amount of carbon; however, steel is nearly infinitely recyclable—steel that is no longer in use is melted down to create new steel products. When a building or structure using a helical pile foundation is decommissioned, the helical piles can be recycled. In some instances, where the helical piles are still in serviceable condition, they can even be reused, significantly lowering the environmental impact per use as well as the cost of the project.

It is also the case that steel is an alloy of iron and carbon, two naturally-occurring substances. While untreated steel will suffer from corrosion, helical piles are treated for corrosion resistance. Variants of steel such as stainless steel are wholly corrosion resistant and are neutral and inert in the environment.

This is not the case for concrete foundations. Concrete manufacture is responsible for over 8% of annual global carbon emissions, and carbon emission is an inherent byproduct of the chemical reactions that form cement. And its environmental effect doesn’t stop with manufacturing: It is carbon-intensive to transport, and concrete leaches chemicals into surrounding soil and water when it is poured and when it comes into contact with water and acidic substances.

Helical Piles Reduce Soil Displacement

Helical pile foundations require significantly less soil displacement than conventional foundations. This is because rather than digging out a flat surface onto which to pour a concrete foundation, helical piles are screwed into the soil itself.

Heavy, resource-intensive equipment is used to excavate and level the soil for poured foundations. Then the soil that is displaced during the construction of structures is used as fill or removed from the site, increasing carbon emissions due to the transport of tons of heavy soil.

This soil displacement can have knock-on effects on the landscape, such as risking erosion. Any time soil is displaced, the potential for rain and wind erosion increases. It’s also the case, and particularly so for industrial applications, that there may be unknown contaminants in the sediments being exposed by excavation. Contaminated soil that is exposed can pose risks to human and environmental health.

Increased Durability Improves Sustainability

Deep helical pile foundations are extremely durable. In fact, helical piles can have a lifespan of over 150 years in normal soil conditions. Poured concrete foundations are generally considered to have a life expectancy topping out at about 100 years.

While durability isn’t synonymous with sustainability, the longevity of helical pile foundations does reduce consumption. A stronger, more durable foundation that lasts longer means that it uses less resources over its lifetime since it does not require repair, fortification, or replacement as soon as less durable foundation materials.

Green Tech Applications for Helical Piles

While not an argument for the environmental friendliness of helical piles themselves, it is notable that some key green technologies make use of helical pile foundations. Helical piles are used for (non-roof mounted) solar panel foundations, ensuring that wind and weather don’t affect the stability of the panels.

Helical piles are also used in some wind turbine applications. As with solar panels, wind turbines are top-heavy, requiring deep foundations to ensure their stability. Battery installations, often in conjunction with solar panels, also make use of helical pile foundations, necessary because of their weight.

For applications like solar panels, helical pile foundations have an additional environmental benefit in that they take up less surface area on the ground. This is beneficial because it means less of the surface is impermeable. This is a boon for plant life, which grows in soil, not concrete, but also protects the soil against erosion from runoff. Impermeable surfaces like concrete prevent stormwater from filtering back into the groundwater naturally, which can cause drainage and infrastructure issues and contribute to flooding.

Learn More About Your Helical Piling Options

If you’re looking to invest in a more eco-friendly foundation solution, helical piles are your go-to. With unmatched durability, minimal installation vibration, and recyclable materials, helical piles not only outperform poured foundations, but they’re also more sustainable. Contact our team of helical piles experts at Elite Helical to learn more.

6 Helical Pile Foundation Design Considerations

6 Helical Pile Foundation Design Considerations

Before helical piles are installed, there are a few design considerations you need to make to ensure they’ll effectively support the intended structure. Without taking into account the size and shape of the piles, the type of soil, the pile capacity, and other such factors, your design may risk failure. Keep reading for six aspects of helical pile foundation design to consider when planning your industrial construction project.

1. Load-Bearing Capacity

The load-bearing capacity of the helical piles to be used for your project is the first and most important consideration for helical pile foundation design. You need to know whether the piles will be able to bear the load of the intended structure, which informs other aspects of design, like the shaft size, number of piles, spacing, and depth.

There are three primary methods to determine helical pile capacity:

  • Direct capacity measurement
  • Torque correlation
  • Bearing capacity in the soil

At least two of these methods should be used in conjunction when calculating load capacity for helical pile design to ensure accuracy and safety.

2. Shaft Size and Type

There are three main types of helical piles: round, square, and combination. These different shapes are suited to different conditions. The hardness or weakness (looseness) of the soil can inform the shaft type to be used. Some soils may be too hard to use round piles, and square or combination shafts may be required. Conversely, round shafts are better suited to loose, weak soils due to the compressive loads they’ll experience in that soil condition.

3. Spacing of Helical Piles

The spacing of helical piles depends both on the number of piles you need to safely bear the load of the structure and the size of the helical plate. The helical plate (also referred to as the helical bearing plate or helix) is one pitch (complete revolution around the pile) of the screw thread. The larger the helical plate, the larger the minimum spacing required.

Since the helices do not extend the entire length of the helical pile, maintaining the necessary minimum spacing is necessary not at ground level, but at bearing level, where the helices are in their final installed position. For structures that require additional load bearing capacity, helical piles can be installed at angles that ensure minimum spacing at bearing level while reducing spacing at ground level.

4. Depth of Helical Pile Installation

Like other deep foundations, helical piles are generally installed at greater than 3 meters below the ground’s surface. The depth should be at least 6 times greater than the diameter of the biggest helix, as measured from the top of the pile to the uppermost helical plate.

Increased depth = increased torque = greater load bearing capacity.

For applications where the soil doesn’t provide enough friction to support the load of the structure at shallower depths, longer, deeper helical piles may be required. Challenging landscapes, such as offshore construction, may require deeper foundations, to support the weight of the installation in water and sand.

5. Soil Type

It’s crucial to consider the soil type when designing a helical pile foundation, as the strength of the load bearing capacity of the piles depends on the torque applied to the piles due to resistance from the soil. When considering soil type for helical pile installation, soil is classified into two general types: fine-grained and granular. Fine-grained soils have a diameter of less than 0.075mm; granular soils have a diameter of greater than or equal to 0.075mm.

Type of soil Classification
Clay Fine-grained
Silt Fine-grained
Gravel Granular
Sand Granular

6. Location and Environment

In addition to the soil present at the construction location, there are other environmental factors to consider that are location specific. Given that helical piles are driven deep into the soil, it’s also critical to know that there are no obstructions where your piles are to be sunk.

This entails more than just calling Miss Dig—you need to ensure that there are no underground utilities, impenetrable rock, caves or caverns, underground water sources, pockets of natural gas or oil, or even just the ruins of old structures or debris. Anything that could impede the screwing in of a helical pile or reduce its torque could compromise the integrity of the foundation.

Helical pile foundations are revolutionizing foundation design with distinct advantages over poured foundations in difficult landscapes and heavy industrial applications. But it’s important to consider the above factors in your helical pile design. If you need help with helical pile design for your construction project, contact a trusted helical pile installer.

Interested in using helical piles to support your next construction project? You’re going to need a solid design before getting started. As your turnkey helical pile contractor, Elite Helical can help with all steps of the process — from design to supply to installation. Contact us online today.

How to Determine Helical Pile Load Capacity

How to Determine Helical Pile Load Capacity

Helical piles are used to create strong, steady foundations with the ability to bear heavy loads in unique or difficult terrains. Because of their critical function in supporting foundations for industrial applications, it’s important to know exactly how much weight helical piles can support.

Since the capacity of a helical pile depends on the material and construction of the pile itself, as well as the landscape and soil into which it is being placed, among other factors, the load capacity must be calculated for the specific type of helical pile and application.

There are three primary methods to determine helical pile capacity:

Torque Correlation

Torque correlation, also known as the torque-to-ultimate holding capacity relationship, is an empirical method for determining helical pile load capacity. This method holds that as a helical pile is installed via screwing into soil that is increasingly hard and dense, the torque—the resistance to installation—will increase. The higher this torque, the higher the axial capacity (the ability to bear load along the vertical axis of the pile).

In layman’s terms, the denser the soil, the greater the load capacity of the helical pile.

To determine the torque correlation, multiply the torque correlation factor (Kt) by the average installation torque (T) to get the ultimate uplift capacity (Qult). As a formula, this would be:

Qult = Kt x T

The torque correlation factor is based on the size and type of helical pile and is inversely related to shaft size.

Bearing Capacity in Soil

To determine helical pile capacity using the bearing capacity in soil method, theoretical calculations are made based on soil strength data. This data can be derived during a Standard Penetration Test (SPT), wherein the soil is drilled for soil sample collection and the resistance to drilling is measured.

The data collected during soil sampling and penetration testing includes the soil profile, groundwater, unit weight, and soil classification. Soil is classified as either:

  • Fine-grained, such as silt or clay
  • Granular soil, such as gravel or sand

Different soil grain sizes can result in different amounts of friction against the piles as they are installed, and therefore different levels of torque. As discussed previously, torque during installation affects the load capacity of the pile.

Using this soil strength data and information about the proposed helical piles and pile configuration, engineers can calculate the helical pile capacity in the proposed installation condition.

Direct Capacity Measurement

The direct capacity measurement method of determining helical pile capacity consists of performing a load test on an installed pile, to comply with the ASTM Standard Test Methods for Deep Foundations Under Static Axial Compressive Load. As this method actually tests the capacity of a helical pile under operating conditions, it is the most accurate method for determining load capacity.

In a direct capacity load test, compression load is applied to the installed helical pile in increments for defined intervals, until the maximum test load is reached, or the pile fails and can’t bear any more load. At each increase in load, the movement/settlement of the pile is measured, and this information is used to determine the capacity of the helical pile.

Due to the importance of accurately gauging the load capacity of helical piles to ensure a strong and durable foundation for the application, it’s recommended that helical pile capacity be calculated using at least two different methods.

While some geoengineers and firms allow for the use of only the torque correlation method to determine helical pile capacity in specific instances, as load testing and collecting soil data can be costly and exceed project budget, this should only be done if the calculations use an increased safety factor to ensure safety in the absence of more complete data.

Helical piles are one of the strongest foundation solutions on the market. If you’d like to use them for your upcoming project, contact the team at Elite Helical. We can help you install helical piles properly, quickly, and safely, so you can enjoy the benefits of helical piling to the maximum degree.