Helical Piles

Helical piles are defined as a central steel shaft with one or more helix shaped bearing elements that is rotated into the ground to support the loads of structures. Other names for helical piles are Helical Piers, Screw Piles, Torque Anchors, Auger Screw Piles, and Helix Piers. Helical Piles were invented in 1836 and were primarily intended for coastal construction. Early applications included lighthouses, marina piers, bridges, and other coastal structures. Their ease of installation in ground water and their resistance to scour makes them ideal for shoreline construction. Helical piles are available in a variety of different sizes to accommodate residential, commercial, and industrial applications.

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Why a Magnum Helical Pile?

The Benefits of Magnum Helical Piles / Helical Piers:
•    Resist scour and undermining for bridge applications
•    Can be removed for temporary applications
•    Are easily transported to remote sites
•    Torque is a strong verification of capacity
•    Can be installed through groundwater without casing
•    Typically require less time to install
•    Can be installed at a batter angle for added lateral resistance
•    Can be installed with smaller more accessible equipment
•    Are installed with low noise and minimal vibrations
•    Can be grouted in place after installation
•    Can be galvanized for corrosion resistance
•    Eliminate concrete curing and formwork
•    Do not produce drill spoil
•    Minimize disturbance to environmentally sensitive sites
•    Reduce number of truck trips to site
•    Are cost effective
•    Can be installed in areas with a high water table
•    Can be installed under a home that has been lifted
•    Are readily available at our distributer in central Jersey
•    Magnum helical piles and materials are MADE IN AMERICA

When it comes to stabilizing a foundation, the amount of benefits that helical piles provide makes it a very each decision.  Helical piles are the most accurate, environmentally friendly, and cost effective way to support the load of a structure.  We have helical piles in stock for your future or current project.  Call us today to get the most reliable helical piles on the market!

    What is a Helical Pile?

    A helical pile is a manufactured steel foundation consisting of one or more helix shaped bearing plates affixed to a central shaft that is rotated into the ground to support structures. Helical piles are made of many different parts that work together in order to support a structure.
    The first part that enters the ground is referred to as the “lead”. It is called the lead because it is the first section to enter the ground when installing a pile. At the tip of the lead is the “pilot point” which is tapered in order to facilitate positioning and proper installation. On the lead, there are usually two helical bearing plates that will ultimately be the most important part of the pile that stabilizes and supports the structure. The lower portion of each helical bearing plate is known as the leading edge while the higher portion is called the trailing edge. The distance between the leading edge and trailing edge is known as the pitch.
    The following portions of the pile are called extensions. These extensions help to drive the pile deeper into the earth until the desired torque ratio is reached. Each extension is usually compromised of only three parts: the coupling, the shaft, and the bracket. The coupling is the piece that attaches to the lead or any additional extensions, the bracket is used at the end of the pile when the desired torque ratio is reached, and the shaft connects those two pieces together.
    For more specific definitions on the parts of a helical pile, please refer to the glossary of terms below:
    Lead – First section of a helical pile to enter the ground; consists of a pilot point, central shaft, and one more helical bearing plates.
    Pilot Point – Short section of shaft with tapered tip extending below the lead helix; facilitates positioning and proper installation.
    Pitch – Distance between the leading and trailing edges of a helix; also, the approximate distance a helical pile should advance per revolution.
    Helical Bearing Plate – Generally circular steel plate pressed in a spiral shape with uniform pitch. The helix is welded to the shaft and used to install the helical pile in a screwing action into the ground and to transfer the load from the shaft into the surrounding soil or rock material.
    Extension – Sections of central shaft with or without helical bearing plates used to extend the lead section of a helical pile to greater depth and form a continuous column of steel in the ground. Extensions with helical bearing plates often are required in very soft soils or in soil nail applications.
    Coupling – Pinned, bolted, or welded connection of two helical pile shafts.
    Shaft – Central tubular or solid steel column that makes up the core of a helical pile and transfers loads from the helical bearing plate to the pile butt; typically square or round cross-section, although other shapes may be used.
    Bracket – Manufactured steel cap or assembly that attaches to the helical pile butt and is used to transfer loads to new or existing foundation elements; examples include angle bracket, plate bracket, new construction cap.

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    Why use helical piles over other foundation systems.

    When it comes to installing a foundation system, a helical pile system is the easiest and most convenient. From delivery to removal (if necessary) there is no other system like it. Delivering the product to a site is very simple considering that the piles are light and can fit on most flat-bed trucks. High load bearing or specialty trucks are not necessary.
    In addition, the equipment used to install the helical piles is much smaller, easier to operate, and quieter than the equipment needed to install other foundation systems. For example, timber piles require a large pile driver in order to install them properly. However, the anchor drives used in the helical pile installation process are significantly smaller which gives them the ability to be used in adverse conditions such as sites with limited space, uneven terrain, inclement weather, etc.
    The assembly is very simple as well. As the pile drives deeper into the earth, extensions can easily be added until the ideal depth and torque ratio is reached for each pile. Considering this, even when adverse conditions such as caving soils, sink holes, and groundwater exists- helical piles are still able to clear those conditions and reach the optimum torque ratio required for the structure.
    The installation process is quick as well. A project with even up to 20 piles can take just a few hours to install which makes it much quicker than many other foundation systems. Furthermore, the piles can be removed in the event that the structure is temporary, the pile is incorrectly installed, or the construction plans change.
    Nevertheless, the most important and beneficial feature of a helical pile is that it provides more accurate load bearing data than any other system available. Not only is torque considered a more precise measurement by leading engineers, but it is also easily and accurately measured through the latest technology in helical pile installation. The torque can be measured at multiple intervals which allows the construction team to be absolutely certain that the load bearing capacity is met by each and every pile.

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    Types of Structures That Use Helical Piles as a Foundation System

    Due to the many benefits of helical piles, they are used in almost any type of structure in order to support its foundation. From transmission towers to light houses, they have been utilized to effectively support structures.

    Homes Near Bodies of Water

    Bodies of water such as lakes and oceans can cause extremely adverse conditions like flooding, tidal surges, land erosion, ground water in the earth below the structure and much more. The use of helical piles can navigate all of these obstacles in order to ensure the structure is stable and can withstand any type of natural adversities caused by a nearby body of water.

    Homes in Mountains

    Attempting to install any type of pile that would require a pile driver can be incredibly difficult. However, the helical pile is much easier to install and the anchor drives used to install the piles are much easier to transport into construction sites with little room to maneuver.

    Lighthouses

    In many cases, lighthouses are built incredibly close or sometimes even in oceans in order to provide an optimal amount of visibility for boats out at sea. Due to its proximity to the ocean, the structure must be able to withstand flooding and whatever tidal strength the ocean may have in an event such as a hurricane. Helical piles are used to support these structures to ensure that it can withstand any type of conditions the ocean may have at any given time.

    Transmission Towers

    In order to erect and stabilize a transmission tower, high tension wires are required. In this instance, helical piles are installed at a batter angle in order to keep the wires in a high tension state. Even with the immense amount of tension in those wires, helical piles are able to keep them in place.

    Structures Susceptible to Seismic Events

    In the event that an earthquake were to affect the earth beneath a structure, the structure would be subjected to lateral loads. Lateral loads can cause buildings to tip or sink into the earth if it does not have the proper helical piles supporting it. Large structures will need to have piles that have had a flexible pile analysis performed on them in order to ensure that the structure stays in place during a seismic event.

    Many other structures

    High rise structures, additions to a home, decks, gazebos, nature walks, and many other structures utilize helical piles due to their reliability and advantages over other foundation systems.

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    Helical Pile Installation Steps and Common Helical Pile Terms

    • Attach helical pile lead section to torque adaptor using drive pin.

    • Center helical pile over planned pile location

    • Push pilot downward until bottom helix makes contact with ground surface

    • Check plumbness

    • Check alignment and plumbness of torque motor and all linkage

    • Begin Rotation while applying downward crown

    • Continue installation, check plumbness as required

    • Record depth and torque readings at select intervals

    • Stop at ground surface so that operator can see drive pin clearly

    • Add extension sections as necessary

    • Continue installation and check plumbness as required

    • Halt installation when specified depth and torque are achieved

    • Cut shaft to final elevation

    • Drill bolt holes as necessary

    • Mount Pier Cap

    • Record final depth, torque, and elevation

    Helical Pile – Manufactured steel foundation consisting of one or more helix-shaped bearing plates affixed to a central shaft that is rotated into the ground to support structures.

    Helix – Generally circular steel plate pressed in a spiral shape with uniform pitch. The helix is welded to the shaft and used to install the helical pile in a screwing action into the ground and to transfer the load from the shaft into the surrounding soil or rock material.
    Extension – Sections of central shaft with or without helical bearing plates used to extend the lead section of a helical pile to greater depth and form a continuous column of steel in the ground. Extensions with helical bearing plates often are required in very soft soils or in soil nail applications.
    Drive Pin – Pin used to connect a helical pile butt to a drive tool on a torque motor; typically a high strength smooth round pin, although any dowel of appropriate strength can be used.
    Shaft – Central tubular or solid steel column that makes up the core of a helical pile and transfers loads from the helical bearing plate to the pile butt; typically square or round cross-section, although other shapes may be used.
    Plumbness – Deviation of a helical pile shaft from vertical.

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    Installation Tips

    Clear Utilities:

    Always locate and clear underground utilities and structures prior to pile installation. Pot-hole to accurately locate utilities close to planned piles

    Reduce Pile Deviations:

    Use a drive tool that is closely matched to the helical pile shaft size and long enough to properly engage the pile. Short or loose-fitting drive tools can cause excessive wobble during rotation.

    Repeat Lifting of Portable Torque Motors:

    Use a block-and-tackle system for repeat lifting of portable torque motors, especially when working with short sections in confined areas.

    Controlling Plumbness:

    For a better control of plumbness, an installation assistant should observe the helical pile at a vantage point that is perpendicular to that of the operator

    Increase Crowd:

    If needed, more crowd sometimes can be achieved by securing the installation machine to a helical anchor installed as a temporary reaction

    Difficult Couplings:

    Correct dimpled round shaft bolt holes by removing the coupling bolts and rotating the drive tool several revolutions prior to decoupling. When necessary, use the machine to force the next extension

    Stubborn Bolt Holes:

    If necessary, align stubborn bolt holes using a drift pin.

    Toxic Fumes:

    Cutting, welding, or grinding galvanized coatings can result in the production of toxic gases. Perform these activities only with proper ventilation and safety equipment.

    Improve Placement Accuracy:

    Position lead section over marker and, without rotation, use downward pressure to push pilot point into the ground until first helix rests at ground surface. Check and adjust plumbness, and then begin rotation while maintaining constant downward pressure.

    Removing Helical Piles:

    When removing helical piles, it is important to limit the tensile force applied to the pile. Some hydraulic machines can apply excessive tensile loads to helical piles. Since they are pulling against the earth, the force is not limited by the weight of the machine.

    Drilling Bolt Holes:

    The effectiveness of most drill bits is enhanced with low speed and high pressure. Drill pressure can be increased using a pry bar. If available, an electromagnetic drill press is very effective.

    Thru Bolts:

    Each side of a tubular pile shaft can be drilled independently with perfect alignment for a thru bolt by using a tubular jig with pre-aligned guide holes. The jig is slid over and securely clamped to the top of a pile shaft.

    Limit Torque:

    To avoid overstressing helical piles during installation, it is feasible to install an inline pressure-relief valve on the supply and return hydraulic hoses.

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    Environmental Sustainability

    Helical pile foundations are an environmentally conscientious and sustainable construction practice. They are much more efficient and environmentally beneficial than drilled shafts, driven h piles, or timber piles. This is mainly due to the difference in installation, manufacturing, and delivery of the piles. The installation of helical piles requires less materials to install than other piles which ultimately reduces truck trips. The manufacturing of the pile itself requires much less material than the other foundation options. The delivery of the piles is more efficient due to their overall size and weight as well. Read on to find out, in more detail, why helical piles are the most environmentally sustainable foundation system.

    Less raw materials

    The unique configuration of helical piles consisting of large bearing surfaces and slender shafts is an efficient use of raw materials. The construction of helical piles utilizes 65% less raw materials compared to driven steel piles and 95% less raw materials than drilled shafts or augercast piles.

    Fewer truck trips

    Not only are fewer trucks needed to install helical piles over other foundations systems, it also reduces the types of trucks needed to go to the construction site. For instance, it only takes a total of 3 truck trips made by two trucks to install 50 helical piles. On the other hand, it takes a total of 17 trips and 4 different truck types to install 50 drilled shafts and a total of 7 trips and 3 truck types to install 50 driven H-piles. The alternative foundation systems require significantly more truck trips than a helical pile foundation system.

    Better for environmentally sensitive areas

    If you are dealing with an environmentally sensitive area, helical piles are your best choice. The lightweight materials and installation equipment minimizes disturbance and ultimately makes less of an impact on fragile ecosystems.
    Overall, helical piles may be the most environmentally friendly deep foundation systems.

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