Why Structural Foundations?
1. Because you can save up to 50% in foundation cost without any sacrifice in structure performance, durability, quality, or safety.
2. Because Structural Foundations are suitable and cost-effective substitutes for many uses of deep foundations, piles (h-piles, pipe piles, screw piles / helical piers), concrete caissons, aggregate piers, and large concrete pours.
3. Because foundation capacity is verified during the installation process. A Structural Foundation is a tested foundation.
4. Because Structural Foundations are made of the same materials as steel piles, providing the same or greater longevity, and fabricated in the U.S. with American steel.
5. Because Structural Foundations are professional engineer (P.E.) stamped for the respective jurisdiction of foundation installation.
Immediately ready to build on!
No cure time
Installation in mere minutes to an hour
Year-round installation, even in frost
Towers & Columns
Structural Foundations are customized for each application and consist of a steel pipe having welded steel fins and a steel top cap. Foundations that primarily resist moment and sliding forces have wide fins, while foundations that primarily provide bearing capacity have tapered fins. Foundations are fabricated in the U.S. by AWS-certified welders using American steel and hot-dip galvanized when specified. For high uplift applications, foundations are mated with our hydraulically-installed anchor systems.
For high overturn and sliding forces, the wide fins of our moment foundations multiply resistance to overturn and sliding per foot of foundation depth, providing superior economics and performance.
For high-capacity applications and especially those in poor soils, our bearing foundations achieve the highest capacities at the shallowest foundation depths compared to alternative approaches, providing the most economical solution.
Just weld or bolt your structure to, or pour concrete over, the installed foundation!
Small-diameter hole drilled.
Anchor inserted, hydraulically actuated, and soils pre-stressed.
Steel foundation hydraulically installed using anchor rod.
Anchor removed (or kept in place for high-uplift applications). Hydraulics removed. Voids filled with the excavated material. Steel foundation secure and ready to be built upon.
Installation Features & Benefits
After drilling, most foundations require only mere minutes up to an hour.
Equipment with a drilling attachment or a small drilling rig + Front-end loader or small crane to lift foundations + Compact hydraulic system.
None! Spoils from drilling are minimal and most can be returned to the pipe of the foundation or easily and thinly spread in the vicinity.
None from foundation installation! Minimal vibration from drilling.
Individual Structural Foundations have achieved the following impressive capacities:
600+ kips bearing capacity in moderate-strength soils
600+ kips uplift resistance capacity in moderate-strength soils
300+ kips bearing capacity in very poor soils
300+ kips uplift resistance capacity in very poor soils
1,000+ ft.-kips overturning moment capacity in poor soils
"The foundation strength is proven during the installation process, as the hydraulically applied installing load is the same as the uplift and bearing capacities.
"Another unique feature of the foundation is the ability to increase the natural bearing capacity of the soil."
- U.S. Department of Energy, NREL, Cooperative Research and Development Agreement, 2004
Our installation process is made possible by our proprietary hydraulically-actuated anchors. Our methods of anchor use coupled with anchor design features enable use to achieve hundreds of kips of resistance, even in poor soils, for installing our foundations. In some applications, our anchors are left in place in order to provide high uplift resistance. We install our anchor systems for a variety of applications, including those that don't require our steel foundations.
1. Cost Savings
Structural Foundations save 25% to 50% over deep foundations, piles (h-piles, pipe piles, screw piles / helical piers), concrete caissons, aggregate piers, and large concrete pours.
2. Time Savings
Immediately ready to build on
No cure time
Installation in mere minutes to an hour
Year-round installation, even in frost
Structural Foundations are entirely prefabricated and can be installed and built upon the same day, regardless of the ambient and ground temperatures (including frost). Installation time ranges from mere minutes to one day per foundation, depending upon foundation size.
As set forth by the American Concrete Institute (ACI) Committee 301, minimum time for concrete curing corresponds to 70% of its specified compressive strength. In common practice, this usually is seven days’ cure time for small-volume concrete installations and 14 to 28 days’ cure time for large-volume installations. That’s seven or more days until concrete achieves sufficient strength to be built upon.
Structural Foundations accelerates the construction schedule, saving project costs, and yielding earlier use / revenue for project owners.
6-ton bearing foundation installed in under one hour and ready for immediate construction. Wind turbine installation in Jackson, Michigan.
Earlier project completion = Earlier use / revenue.
3. Verified Bearing
Verified bearing capacity established before use
Settling and creep virtually eliminated
In installation, the bearing capacity of Structural Foundations is measured and verified. Impressive bearing capacities exceeding 300 tons (600 kips) per foundation have been achieved.
Structural Foundations are hydraulically installed. This supplies an accurately applied and known force throughout the installation, including foundation and soils in its zone of influence. The installing force is applied in either a stress or strain controlled manner as dictated by soil conditions. This process directly pre-stresses and pre-tests the strength of the surrounding soils and the system’s overall ability to meet and exceed the loads specified. Structural or geotechnical engineers supervise installations and complete records that verify installed loading.
The Structural Foundations system and method of installation consolidates or compacts soils and combinations of soils and rock. This is accomplished by any combination of (1) applied bearing forces that develop and / or utilize the soils’ bearing capacity, and (2) frictional forces that enact, develop, and / or utilize the passive lateral strengths of soils. This virtually eliminates settling and creep of the structure at loading equal to or less than the applied installing load.
Bearing capacity is indicated by the hydraulic system’s gauges and verified by an on-site engineer.
100+ year durability
Galvanized coating for corrosion resistance
30+ years of field performance data
Fabricated from high-strength structural steel and galvanized in accordance with ASTM A123 / A123M standards, Structural Foundations can achieve a maintenance-free lifetime of 100+ years. These are robust materials with known durability and properties, providing superior corrosion resistance both beneath and above ground. Galvanized coatings are ubiquitous on construction materials and hardware having steel substrates. With installations since 1986, not one Structural Foundations product has required maintenance.
Structural Foundations have been installed in high-moisture, high-erosion areas without any observed or measurable degradation in structural integrity. Our galvanized foundations have been installed for multiple riparian flood walls, where submersion in water is common.
Lifetime reliability and low costs.
Galvanized foundation for a 120-foot tall road lighting tower in Charleston, West Virginia.
5. Versatile Installation
Installs in poor soils and rock
Few equipment needs
Well suited to both remote and urban areas
No disposal necessary for excavated materials
Geotechnical conditions pose little challenge to the installation of Structural Foundations. Structural Foundations consolidate and compact soils, improving their load bearing, and the method of installation accurately measures soils’ minimum bearing capacities. In contrast, traditional foundation systems are designed to utilize existing strengths of soils, and where soils are deficient, require uneconomical soils remediation in installation or larger safety factors in design. As well, inconsistencies in soil conditions across an installation site challenge the performance of traditional foundation design. Structural Foundations can be installed in soils where traditional concrete and / or pile systems are impractical or highly uneconomical.
Equipment requirements for installation aren’t intensive. Most sizes of Structural Foundations can be installed quickly and capably with a small crane and a compact hydraulic system. Structural Foundations can be equally valuable to projects in remote areas with rugged terrain as in densely populated cities where jobsite space is scarce. An added benefit of Structural Foundations is minimal excavation requirements, with all excavated materials returned to the foundation system during installation.
Install virtually anywhere.
6. Removable and Reusable
Can be removed and installed over and over again
Minimal infill of soils necessary
Portable, one-piece integral design
Desirable in jurisdictions requiring environmental restoration and reclamation
With minimal site disruption, installations of Structural Foundations can be removed and reused. Quick removal, often ranging from five minutes to under one hour depending upon size, is accomplished with a similar hydraulic process as in installation. Structural Foundations can be reused again and again as uses and locations change. One-piece integral design provides portability and ease in re-installation. Where removed, only minimal infilling of soils is necessary. Structural Foundations may be particularly attractive for installation in jurisdictions that regulate environmental restoration and reclamation. With Structural Foundations, you pay once for a foundation that could have many uses and installation locations.
Suited for permanent and temporary uses.
Structural Foundations installation for a signal tower. Located atop Pea Ridge in the Appalachian Mountains, near Charleston, West Virginia.
Removal of Structural Foundations begins with hydraulic lifting, performed in the reverse manner as in installation. For small foundations, a front-end loader can complete the lifting action to remove. For larger foundations, a crane is necessary.
7. Environmentally Compatible
Ideal for sensitive environments
Minimal site disruption
Lower carbon footprint than concrete foundations
Sensitive environments, where site disruption and major excavation compromise fragile ecosystems, watersheds, and compliance with regulation, may especially benefit from Structural Foundations. Site disruption and deformation of ground cover is minimal.
The minimal heavy equipment needs for Structural Foundations installation reduces soil compaction and damage to vegetation. Installations can be accomplished within the immediate vicinity of buildings, trees, and utilities. Most overhead obstructions from vegetation do not require removal.
Made of steel, Structural Foundations have a smaller carbon footprint than concrete foundations designed for similar bearing capacity.
Stewardship of natural resources.
8. Validated Performance
Third-party validated performance
Withstood 100% of design loads
The National Wind Technology Center (NWTC), a department of the National Renewable Energy Laboratory (NREL), conducted a Cooperative Research and Development Agreement (CRADA) on our custom foundation installation for a 50kW wind turbine in Colorado. The CRADA was prepared by Dave Corbus and Jason Cotrell, and released May 17, 2004. It also evaluated the viability of our installation for large and small wind turbines. Significantly:
“[The] bearing foundation is unique among wind turbine foundations in that the foundation strength is proven during the installation process as the hydraulically applied installing load is the same as the uplift and bearing capacities. Another unique feature of the foundation is the ability to increase the natural bearing capacity of the soil, the installation test was designed to show the system’s ability to greatly increase this bearing capacity within the load bearing zone of influence.”
“The confined compressive strength of the soil was increased 3.4 times during installation of the foundation.”
“Further testing would not be required, as the bearing foundation system exceeded all of the design requirements. It is recommended that the bearing foundation system be considered for use in appropriate wind turbine applications.”