Helical Piles – FAQS

Helical pilings, also known as screw piles, represent an innovative approach to deep foundation piles in construction. Characterized by their unique design, these piles feature spiraling helices along their steel shafts, distinguishing them from traditional deep foundation options like steel/concrete driven piles and micropiles. This distinct corkscrew design allows for more effective penetration and anchoring into the ground.

Helical piles are made from steel that has been hot dipped in galvanized coating for rust protection. Affordable Foundation’s piles typically come in either round hollow shafts or solid square shapes, crafted from ASTM-compliant steel. These piles are available in different diameters and square shaft sizes, depending on the requirements outlined in the engineer’s design. An essential aspect of an engineer’s design for these piles includes considering the geological composition of the subsurface soils

Helical piles with square shafts are suitable for both tension and compression uses. In contrast, round shaft helical piles are typically utilized for compression purposes and offer better resistance to bending, especially in weaker soils. In Florida, the preference is to use round shaft helical piles for new buildings, while square shafts are often employed for grouted micro piling and reinforcing seawall tiebacks.

The helical lead, measuring seven feet in length, can feature either a single or multiple helical blades, often called bearing plates. These blades differ in their dimensions, designs, and numbers. The helix plates are securely attached to the primary pile shaft through welding, ensuring appropriate spacing between the blades. To enhance the lead’s penetration into the soil and bolster its capacity, extensions are use

Screw piles, while having a long history, are a recent addition to Florida’s construction techniques. Elsewhere, they’ve been integral in constructing railways, stabilizing runways, and facilitating large-scale engineering endeavors. Their standout feature is the combination of versatility and simple installation. Affordable Foundation Repair offers efficient installation of high-capacity screw piles, even in tight spaces, using compact machinery. This method produces minimal waste, operates quietly, and avoids vibrations that could disturb nearby residents.

Screw piles are selected for their efficiency in scenarios necessitating deep foundations or construction near pre-existing buildings. They typically present a cost-effective and pragmatic solution, with minimal environmental impact. Compared to conventional foundation approaches and anchoring methods, helical piles have numerous benefits. Unlike augercast piles that require a curing period for the concrete, screw piles are capable of supporting loads right after they are installed. In Florida, they are commonly employed for home expansions, building new swimming pools or hardscapes, marine construction, and foundation reinforcement.

Installing helical piles is a straightforward process. These piles are twisted into the ground, similar to how a large screw is driven into wood. Affordable Foundation Repair uses a suitably sized excavator equipped with a hydraulic anchor drive to apply the necessary torque for inserting the helical piles into the earth. The procedure for setting up these piles varies greatly, depending on the project, especially in coastal regions. The equipment needed for a century-old wooden building differs markedly from that required for a contemporary five-story concrete office structure.

The key factor in designing helical piles lies in precise structural and geotechnical engineering. Each installation of helical piles is distinct, necessitating tailor-made designs and varying load-bearing capabilities. The capacity of helical piles depends on several variables, including the pile’s design, soil conditions, and the required depth for achieving adequate torque. Notably, a single helical pile can support up to 500 tons, though collectively, their capacity can be significantly greater. It’s important to note that tension forces pull materials apart, while compression forces press materials together.

Helical piles can be installed in various confined spaces, including areas as narrow as a walk-in shower. Affordable Foundation Repair boasts an array of specialized machinery suitable for tight spaces, alongside larger excavators for more open areas. The equipment and installation processes they employ are notably more compact than those used in other pile installation techniques.

Torque refers to the rotational force needed to install a helical pile. Different helical pile designs need varying levels of torque depending on their designed capacities for tension or compression. The torque requirement is higher in denser soils, while more cohesive soils require less torque. Additionally, square shaft piles feature a KT factor of 10, whereas round shaft piles, specifically those with a 3” diameter, start with a KT factor of 9.

In our operations, we exclusively employ hot-dipped galvanized materials and components. Due to Florida’s tropical climate and the presence of harsh marine seawater, which infiltrates our groundwater, there’s an increased risk of corrosion. The galvanizing process we use offers an exceptional shield against rust and corrosion, ensuring a durability that can extend up to 100 years.

The spiraling helices dig into the ground, generating torque as they go deeper, thereby offering support. The helix flights bear the load as per the engineered design. This process is often known as compressive capacity or true end bearing capability.

In Florida, the necessary depth for installing helical piles varies due to several factors, such as soil composition, required load capacities, and diverse site-specific conditions. Typically, these screw piles are designed to reach a depth where they can effectively handle the critical load requirements. The installation depth is crucial because the helix plates on the screw piles are responsible for bearing the structure’s weight and distributing it into the ground. These helical piles, featuring multiple helices, are arranged along the pile shaft, enabling them to reach and anchor in stable soil layers deep underground. Depending on the engineering design specifications, the depth of screw piles can range from at least 14 feet to more than 70 feet. The specific conditions will determine the torque and load capacity that the pile must sustain.

Our screw piles are fitted with a digital torque indicator to measure the applied torque capacity. Should the pile fail to reach the predetermined engineering capacity, it must be driven deeper into the ground by attaching additional extensions. These extensions continue until the pile reaches a soil layer firm enough to fulfill the engineering criteria.

Before beginning any construction or building project, conducting a geotechnical investigation is crucial. Building on unstable foundations can lead to significant structural damage. The integrity of these foundations depends largely on the soil type where the footings are placed. Clay soils, for example, can expand or contract with changes in moisture, leading to potential settlement issues due to soil compression or use of fill materials.

Helical or screw piles are becoming increasingly favored in Florida, particularly following Hurricane Ian. Design engineers have noted their significant advantages, as structures built on these piles have withstood recent hurricanes. Helical/screw piles offer a versatile and dynamic foundation solution, bringing a wide array of benefits, such as:

Helical piles, while innovative in the realm of deep foundations, have certain limitations:

A hydraulic gear motor attached to a small excavator or a larger 50,000-pound excavator is utilized for driving a hot dip galvanized helical pile into the ground. The torque applied during installation is carefully monitored to ensure it meets the required engineered load capacities. After installation, a steel termination plate is either welded or bolted to the top of the pile, which is then integrated into the newly poured concrete foundation.

Homes in Florida are at risk of foundation sinking due to settlement. Signs of this issue include cracks in exterior walls and difficulty in opening windows and sliding doors. To address this, underpinning is used to strengthen existing foundations in both residential and commercial properties that can no longer support their current loads. This process involves installing helical piles into the ground, which are then connected to a concrete footer with a bracket. This method is necessary when the lowering of the ground level causes foundations to sink, often due to changes in soil moisture, water runoff from roofs, or failing retaining walls.

Affordable Foundation Repair specializes in stabilizing foundations using advanced techniques. They install helical pilings by rotating them into the ground until they reach stable soil. Once in place, a high-quality hot-dipped galvanized (HDG) custom bracket is securely attached to the structure’s grade beam or footer pad. To adjust the elevation of the structure, a specialized hydraulic lifting jack is temporarily used. This process ensures that the hot-dipped galvanized bracket remains a permanent part of the footer, effectively maintaining the structure’s corrected elevation.

For those working in pool construction or engineering, helical piles are essential for creating a strong foundation for swimming pools. It’s vital to establish a stable and secure base using helical pile anchors, given the significant weight that water adds to a swimming pool project. This weight bears down on the concrete foundation, necessitating the use of approximately 10 to 16 helical piles for most standard pools to ensure stability and safety.

In certain specific cases in Florida, a method is used where concrete grout is applied around the edges of helical pilings. This technique is mainly used for a type of square shaft pile known as a helical micro pulldown piling. Additionally, there are occasions where the inside of a round shaft pile is filled with grout, aiming to reinforce areas where bolt connections are made.

In certain specific cases in Florida, a method is used where concrete grout is applied around the edges of helical pilings. This technique is mainly used for a type of square shaft pile known as a helical micro pulldown piling. Additionally, there are occasions where the inside of a round shaft pile is filled with grout, aiming to reinforce areas where bolt connections are made.

New evidence has emerged highlighting the effectiveness of helical pilings in Florida, particularly in the wake of Hurricane Ian. AFFORDABLE FOUNDATION REPAIR has been instrumental in installing these pilings across various coastal regions. The scope of their projects is extensive, encompassing swimming pools, hardscape walls, structural concrete slabs, support for cell towers, underpinning and reinforcing foundations for multi-story buildings, as well as marine applications. Helical piles, made of galvanized steel pipe, are designed to anchor new and existing structures securely into solid ground, functioning similarly to traditional driven piles. These piles are environmentally friendly, being recyclable, and offer a clean and efficient installation process, eliminating the need for managing excess soil or removing debris.

New evidence has emerged highlighting the effectiveness of helical pilings in Florida, particularly in the wake of Hurricane Ian. AFFORDABLE FOUNDATION REPAIR has been instrumental in installing these pilings across various coastal regions. The scope of their projects is extensive, encompassing swimming pools, hardscape walls, structural concrete slabs, support for cell towers, underpinning and reinforcing foundations for multi-story buildings, as well as marine applications. Helical piles, made of galvanized steel pipe, are designed to anchor new and existing structures securely into solid ground, functioning similarly to traditional driven piles. These piles are environmentally friendly, being recyclable, and offer a clean and efficient installation process, eliminating the need for managing excess soil or removing debris.