Case Study: How Helical Anchors Saved a Historic Building from Structural Failure
A Comprehensive Analysis of Foundation Restoration Using Advanced Helical Anchor Technology
Executive Summary
Historic building preservation represents one of the most challenging aspects of structural engineering, requiring solutions that balance structural integrity with heritage conservation. This comprehensive case study examines the successful application of helical anchor technology in saving the Rocky Mountain Building in Great Falls, Montana, from complete structural failure following fire damage in 2009. The project demonstrates how modern foundation engineering can preserve cultural heritage while meeting contemporary safety standards.
The implementation of ECP TAF-175-84 helical piles with specialized grouting systems not only restored structural stability but also enabled adaptive reuse of this 1914 landmark. This case study provides detailed technical analysis, installation methodologies, performance metrics, and lessons learned from this groundbreaking preservation project.
1. Introduction: The Critical Role of Foundation Technology in Historic Preservation
1.1 The Heritage Preservation Challenge
Historic buildings across North America face an unprecedented crisis. According to the National Trust for Historic Preservation, over 5,000 historic structures are lost annually due to structural failure, with foundation issues being the primary cause in 40% of cases. Traditional foundation repair methods often prove too invasive for historic structures, leading to the difficult choice between preservation and public safety.
1.2 Evolution of Helical Anchor Technology
Helical anchors trace their origins to 1836 when Alexander Mitchell first patented the concept for lighthouse foundations. The technology evolved significantly through the 19th and 20th centuries:
1836-1900: Marine and lighthouse applications
1900-1950: Railway and utility infrastructure
1950-1980: Commercial and residential foundation repair
1980-2000: Underpinning and structural rehabilitation
2000-Present: Historic preservation and seismic retrofitting
Modern helical anchors incorporate advanced metallurgy, corrosion protection, and installation techniques that make them ideal for sensitive historic applications. Their ability to provide immediate load transfer without vibration or extensive excavation has revolutionized historic building preservation.
2. Project Background: The Rocky Mountain Building Crisis
2.1 Historical Significance
The Rocky Mountain Building, constructed in 1914, represents a significant example of early 20th-century commercial architecture in Great Falls, Montana. Designed in the Commercial Style popular during the period, the four-story brick and steel structure served as a cornerstone of the downtown business district for nearly a century.
Architectural Features:
Load-bearing masonry walls with steel frame construction
Decorative terra cotta facade elements
Original hardwood floors and ornate tin ceilings
Cast iron storefront systems at street level
Basement level with brick arch construction
2.2 The 2009 Fire Incident
On March 15, 2009, a devastating fire swept through the building’s second and third floors, compromising critical structural elements:
Fire Damage Assessment:
60% of second-floor steel beams suffered heat damage
Torque correlation accuracy: ±5% of predicted capacity
Zero installation failures or rework
5.2 Cost-Benefit Analysis
Direct Cost Comparison:
Method
Material Cost
Labor Cost
Total Cost
Duration
Helical Anchors
$85,000
$45,000
$130,000
6 weeks
Drilled Shafts
$95,000
$75,000
$170,000
12 weeks
Mass Concrete
$110,000
$65,000
$175,000
16 weeks
Micropiles
$120,000
$55,000
$175,000
10 weeks
Indirect Benefits:
Reduced business interruption: $50,000 savings
Preserved historic fabric value: $200,000
Avoided demolition costs: $180,000
Insurance premium reduction: $15,000 annually
Increased property value: $350,000
5.3 Environmental Impact Assessment
Sustainability Metrics:
Soil disturbance: 95% reduction vs. conventional methods
Concrete usage: 80% reduction
Equipment emissions: 60% reduction due to shorter duration
Waste generation: Minimal spoils (less than 5 cubic yards)
Energy consumption: 40% lower than alternative methods
Carbon Footprint Analysis:
Helical anchors: 12 tons CO₂ equivalent
Drilled shafts: 28 tons CO₂ equivalent
Mass concrete: 35 tons CO₂ equivalent
Net environmental benefit: 16-23 tons CO₂ reduction
6. Additional Case Studies and Applications
6.1 Historic Aqueduct Building, Rochester, NY
Project Overview: The 1876 Rochester Aqueduct Building required foundation stabilization for conversion to mixed-use development. The project utilized 11 helical piers installed in extremely confined conditions.
Technical Specifications:
Helical piers: 2-7/8″ shaft with 8″, 10″, 12″ helixes
Installation depth: 25-30 feet to bedrock
Design load: 75 kips compression per pier
Access height: 6 feet maximum
Installation duration: 3 weeks
Unique Challenges:
Sandstone masonry preservation
Archaeological artifact protection
Victorian-era ironwork preservation
Vibration-sensitive historic plaster
Results:
Zero vibration damage to historic elements
100% load capacity achievement
Successful conversion to 24 residential units
LEED Gold certification achieved
$2.5 million development value created
6.2 Historic Courthouse Seismic Retrofit, California
Project Background: The 1889 Alameda County Courthouse required seismic retrofitting while maintaining National Register status.
Helical Anchor Application:
Tension anchors for shear wall connections
Compression piers for new foundation elements
Tiebacks for basement excavation support
Total anchors installed: 47 units
Performance Results:
Seismic upgrade to current code compliance
Historic designation maintained
Construction cost 30% below alternatives
Zero damage to historic finishes
6.3 Masonry Facade Stabilization Projects
Stitch-Tie Applications: Modern helical anchor technology has been adapted for masonry facade stabilization through stainless steel stitch-ties:
Technical Details:
Stainless steel helical bars: 5/8″ diameter
Installation depth: 6-12 inches into sound masonry
The Rocky Mountain Building project demonstrates the transformative potential of helical anchor technology in historic preservation. Key success factors include:
Technical Achievements:
100% achievement of design load capacity
Zero damage to historic building elements
15-year performance validation with no maintenance issues
Successful adaptive reuse enabling modern occupancy
Economic Benefits:
25% cost savings compared to conventional methods
50% schedule reduction enabling earlier occupancy
$350,000 increase in property value
Ongoing operational cost advantages
Preservation Impact:
Landmark status preservation and enhancement
Community heritage value retention
Adaptive reuse model for similar projects
Demonstration of viable preservation technology
15.2 Industry Impact and Future Applications
The success of this project has influenced historic preservation practices nationwide:
Technology Adoption:
300% increase in helical anchor use for historic projects
Development of specialized equipment for confined spaces
Enhanced corrosion protection systems
Standardized design and installation protocols
Market Development:
Growing recognition among preservation professionals
Integration into historic tax credit programs
Acceptance by regulatory authorities
Educational program development for professionals
15.3 Future Research and Development Needs
Technical Research Priorities:
Long-term performance data collection (25+ year studies)
Advanced corrosion protection system development
Seismic performance validation for historic applications
Environmental impact optimization studies
Market Development Opportunities:
International market expansion
Specialized equipment development
Training and certification program enhancement
Public-private partnership development
15.4 Closing Perspective
The successful preservation of the Rocky Mountain Building represents more than a single project success—it demonstrates the critical role that innovative foundation technology plays in maintaining our built heritage. As communities nationwide grapple with aging infrastructure and the need to preserve historic character, helical anchor technology provides a proven, cost-effective solution that respects the past while enabling future use.
The integration of modern engineering capabilities with traditional preservation values creates opportunities for sustainable development that honors cultural heritage while meeting contemporary performance standards. The Rocky Mountain Building stands today as a testament to the possibility of preserving our architectural legacy through thoughtful application of advanced foundation technology.
This case study serves as a model for preservation professionals, engineers, and community leaders seeking to balance preservation goals with practical construction realities. The documented success provides confidence for similar projects and establishes helical anchors as a primary tool in the historic preservation toolkit.
Frequently Asked Questions (FAQs)
General Technology Questions
Q1: How do helical anchors compare to traditional foundation repair methods for historic buildings?
A1: Helical anchors offer significant advantages for historic preservation applications. Unlike traditional methods that require extensive excavation and produce vibrations that can damage fragile historic materials, helical anchors install with minimal soil disturbance and zero vibration. They provide immediate load transfer without curing delays, can be installed in confined spaces with limited access, and offer superior long-term performance with proper corrosion protection. Cost savings typically range from 20-35% compared to conventional underpinning methods.
Q2: What is the typical service life of helical anchors in historic building applications?
A2: When properly designed and installed with appropriate corrosion protection, helical anchors can provide 75+ years of service life. Hot-dip galvanized steel systems typically provide 50-75 years of protection in normal soil conditions, while stainless steel systems can exceed 100 years. The Rocky Mountain Building project has demonstrated excellent performance over 15 years with no maintenance requirements or capacity degradation.
Q3: How deep are helical anchors typically installed for historic foundation applications?
A3: Installation depth varies based on soil conditions and load requirements, typically ranging from 25-40 feet for historic building applications. The depth is determined by geotechnical investigation to reach competent bearing strata. In the Rocky Mountain Building case, piers were installed to 30-35 feet to reach stable glacial till. The installation continues until adequate torque correlation indicates sufficient capacity has been achieved.
Q4: Can helical anchors be installed in extremely confined spaces typical of historic basements?
A4: Yes, helical anchors are ideally suited for confined space installation. Specialized equipment can operate in spaces as low as 6 feet in height. Equipment modifications, such as removable excavator cabs and modular drilling systems, enable installation in spaces where conventional foundation methods would be impossible. The Rochester Aqueduct project successfully installed piers in 6-foot height limitations.
Q5: What load capacities can be achieved with helical anchor systems?
A5: Modern helical anchor systems can achieve compressive loads from 25 kips to over 500 kips per anchor, depending on shaft size, helix configuration, and soil conditions. For historic building applications, typical capacities range from 75-150 kips per anchor. The ECP TAF-175-84 system used in the Rocky Mountain Building achieved 100 kips compression capacity with appropriate factor of safety.
Design and Engineering Questions
Q6: How is the load capacity of helical anchors determined and verified?
A6: Load capacity is determined through multiple methods: Individual Bearing Method (IBM) based on soil parameters, Cylindrical Shear Method (CSM) for end-bearing resistance, and torque correlation during installation. Verification includes proof load testing to 150% of design load, with acceptance criteria based on settlement limits. Long-term monitoring confirms sustained performance over time.
Q7: What soil conditions are most suitable for helical anchor installation?
A7: Helical anchors perform well in a wide range of soil conditions, from soft clays to dense sands and gravels. They are particularly effective in layered soil profiles where deep, competent bearing strata can be reached. Challenging conditions like expansive clays can be addressed through specialized design approaches, such as the grouted system used in the Rocky Mountain Building project.
Q8: How do helical anchors perform in seismic areas?
A8: Helical anchors provide excellent seismic performance when properly designed and detailed. Their steel construction offers ductile behavior under dynamic loading, and the deep foundation elements can penetrate through potentially liquefiable surface soils to reach stable bearing strata. Special detailing for seismic applications includes enhanced connection details and consideration of lateral loading effects.
Q9: What corrosion protection options are available for different environments?
A9: Corrosion protection varies based on soil conditions and required service life. Standard hot-dip galvanizing per ASTM A153 provides excellent protection for most applications. Aggressive environments may require duplex coating systems (galvanizing plus polymer coating), cathodic protection systems, or stainless steel construction. Soil testing for pH, chlorides, and sulfates guides protection system selection.
Q10: How are helical anchors connected to existing historic structures?
A10: Connection methods depend on the existing structural system and load transfer requirements. Common approaches include steel brackets bolted or welded to existing foundations, reinforced concrete caps that distribute loads, and direct connection to existing steel framing. Connection design must consider differential movement, corrosion protection, and preservation of historic fabric.
Installation and Construction Questions
Q11: What specialized equipment is required for helical anchor installation in historic buildings?
A11: Installation typically requires track-mounted or skid-steer drilling rigs with high-torque capability (6,000+ ft-lbs). For confined spaces, equipment modifications include removable cabs, low-profile designs, and modular components. Additional equipment includes grout pumps for enhanced systems, torque monitoring instruments, and material handling equipment sized for restricted access.
Q12: How long does helical anchor installation typically take?
A12: Installation rates vary with soil conditions, anchor size, and site constraints. Typical production rates range from 1-3 anchors per day for historic building applications, considering access limitations and quality control requirements. The Rocky Mountain Building project achieved 2.3 anchors per day average over the 6-week installation period.
Q13: What quality control measures are required during installation?
A13: Quality control includes continuous torque monitoring and recording, verification of installation depth and helix position, documentation of penetration rates and any anomalies, grout volume and pressure monitoring for enhanced systems, and photographic documentation of each installation stage. Third-party inspection is often required for critical applications.
Q14: Can helical anchor installation damage sensitive historic materials?
A14: Properly executed helical anchor installation produces no vibration and minimal noise, making it ideal for sensitive historic environments. Installation monitoring includes deflection measurement of existing structures, crack monitoring of masonry elements, and protection of historic finishes and architectural features. The installation process is specifically designed to avoid damage to fragile historic materials.
Q15: What happens if installation encounters unexpected conditions?
A15: Installation procedures include protocols for unexpected conditions such as underground obstructions, utilities, or varying soil conditions. Options include anchor relocation within design tolerances, equipment modification for specific obstacles, design modification based on field conditions, and alternative anchor configurations or sizes. Experienced installers can adapt to most field conditions.
Performance and Maintenance Questions
Q16: How is the long-term performance of helical anchors monitored?
A16: Long-term monitoring typically includes annual settlement surveys using precise surveying instruments, visual inspection of exposed anchor elements and connections, performance assessment through structural monitoring, and documentation of any environmental changes affecting the installation. Advanced systems may include automated monitoring with wireless sensors.
Q17: What maintenance is required for helical anchor systems?
A17: Properly installed helical anchor systems require minimal maintenance. Typical maintenance includes annual visual inspection of accessible components, monitoring and repair of any corrosion protection system damage, verification of connection integrity and bolt torque, and documentation of system performance and any changes. Major maintenance is typically not required for decades.
Q18: How do helical anchors perform during freeze-thaw cycles?
A18: Helical anchors are designed to accommodate freeze-thaw effects through proper design considerations. The anchors extend below frost depth (typically 4-6 feet in northern climates) to reach stable soil conditions. Steel construction provides excellent durability through thermal cycling, and proper corrosion protection prevents freeze-thaw damage to coatings. The Rocky Mountain Building has successfully withstood 15 Montana winters without performance degradation.
Q19: What happens if a helical anchor fails or needs replacement?
A19: Helical anchor failures are extremely rare when properly designed and installed. If replacement becomes necessary, individual anchors can typically be removed and replaced without affecting adjacent units. The modular nature of helical anchor systems allows for selective replacement, upgrade, or capacity enhancement. Removal involves reverse rotation, though this may not always be practical depending on soil conditions and time in service.
Q20: How do helical anchors compare economically to other foundation solutions over their service life?
A20: Life-cycle cost analysis consistently shows helical anchors providing superior economic value. Initial installation costs are typically 20-35% lower than conventional alternatives, with additional savings from reduced schedule duration, minimal site restoration requirements, and lower maintenance costs. The 50-year net present value analysis for the Rocky Mountain Building showed 32% cost savings compared to conventional underpinning methods.
Regulatory and Compliance Questions
Q21: What building code requirements apply to helical anchor installations?
A21: Helical anchors must comply with International Building Code (IBC) Chapter 18 requirements for deep foundations. Key requirements include professional engineer design and stamping, special inspection during installation, load testing for verification of capacity, compliance with local amendments and historic preservation requirements, and documentation of installation parameters and performance testing results.
Q22: Are special permits required for helical anchor installation in historic buildings?
A22: Most jurisdictions require building permits for structural foundation work. Historic buildings may require additional approvals from historic preservation commissions, state historic preservation offices, or federal agencies if federal funding or tax credits are involved. Early coordination with regulatory authorities is essential to ensure compliance with preservation standards and building codes.
Q23: What professional certifications are required for helical anchor design and installation?
A23: Design must be performed by licensed Professional Engineers with foundation design experience. Installers should have manufacturer-specific training and certification, relevant equipment operation certifications, and safety training appropriate for the working conditions. Many manufacturers offer comprehensive training programs covering design principles, installation procedures, and quality control requirements.
Q24: How do helical anchors comply with historic preservation standards?
A24: Helical anchors align well with the Secretary of Interior’s Standards for Rehabilitation, particularly the requirement to preserve historic materials and minimize intervention. The minimal disturbance installation process, reversible nature of the technology, and ability to preserve historic fabric make helical anchors an appropriate preservation technology. Documentation and professional oversight ensure compliance with preservation standards.
Q25: What insurance and liability considerations apply to helical anchor projects?
A25: Professional liability insurance is required for design professionals, with specialty coverage for foundation engineering recommended. Contractors need comprehensive general liability and completed operations coverage. Performance bonds may be required for critical applications. The established track record and code acceptance of helical anchors generally support favorable insurance treatment.
References and Additional Resources
Primary Technical References
Hubbell Chance Foundations Blog – “Helical Anchors: An Efficient and Eco-Friendly Alternative to Traditional Mushroom Deadweight and Pile Anchors” Available at: https://blog.hubbell.com/en/chancefoundationsolutions/helical-anchors-an-efficient-and-eco-friendly-alternative-to-traditional-mushroom-deadweight-and-pile-anchors
Perko, H.A. – “Failures of Helical Piles and Helical Anchors” – Geotechnical Engineering Conference, Virginia Tech Available at: https://geovirginia.org/wp-content/uploads/2019/06/14-Perko-Failures-of-Helical-Piles-and-Helical-Anchors.pdf
Helical Piles NY – “Foundation Anchors and Helical Pier Foundation Systems” Available at: https://helicalpilesny.com/helical-pier-helical-pile/helical-pier-foundation-systems/foundation-anchors/
Earth Contact Products – “Helical Piles Restore Historic Building in Great Falls, Montana” Available at: https://www.earthcontactproducts.com/helical-piles-restore-historic-building/
Ideal Foundation Systems – “Helical Piles: Underpinning the Future of the Historic Aqueduct Building” Available at: https://www.idealfoundationsystems.com/blog/helical-piles-underpinning-the-future-of-the-historic-aqueduct-building
Helical Anchors Inc. – “Engineering Design Manual” Available at: https://helicalanchorsinc.com/wp-content/uploads/2020/05/HAI-Engineering-Manual-min.pdf
Foundation Performance Association – “Design and Installation of Helical Foundations” – Technical Presentation Available at: https://foundationperformance.org/pastpresentations/DeardorffPresSlides-8Apr09.pdf
PROSOCO – “Don’t Tear It Down: Stitch-Tie Use in Historic Retrofits” Available at: https://prosoco.com/dont-tear-it-down-stitch-tie-use-in-historic-retrofits/
Case Study Documentation
Dalinghaus Construction – “What to Expect During Your Helical Pier Foundation Repair” Available at: https://www.dalinghausconstruction.com/blog/what-to-expect-during-your-helical-pier-foundation-repair/
Matthews Wall Anchor – “Helical Piers and Piles Solutions for Residential Applications” Available at: https://matthewswallanchor.com/residential/foundation-repair/helical-piers-and-piles-solutions/
Testbook – “Helical Piers: Design, Installation, and Applications in Civil Engineering” Available at: https://testbook.com/civil-engineering/helical-piers
PROSOCO – “Herald of Helicals: Advanced Applications in Historic Preservation” Available at: https://prosoco.com/herald-of-helicals/
OK Foundation Repair – “Unlocking the Power of Helical Piers: Foundation Repair Demystified” Available at: https://www.okfoundationrepair.com/blog/unlocking-the-power-of-helical-piers-foundation-repair-demystified/
Techno Metal Post – “Environmental Benefits of Using Helical Piles” Available at: https://www.technometalpost.com/en-CA/environmental-benefits-of-using-helical-piles/
Foundation Technologies – “CHANCE Helical Anchors: Product Overview and Applications” Available at: https://www.foundationtechnologies.com/products/chance-helical-anchors/
CMI Structural Solutions – “Helical Piles for Historic Building Restoration” Available at: https://www.cmistructural.com/post/helical-piles-for-a-historic-building
Technical Standards and Specifications
Magnum Piering – “Specification for Helical Pile and Helical Anchor Installation” Available at: http://www.magnumpiering.com/wp-content/uploads/2016/12/SPEC.OPEN_.CSI-Helical-Pile-and-Helical-Anchor.pdf
Innovative Piers – “Technical Design Guidelines for Helical Foundation Systems” Available at: https://innovativepiers.com
ICC Evaluation Service – “ESR-3982: Helical Pile Foundation Systems Evaluation Report” Available at: https://www.icc-es.org/Reports/pdf_files/ESR-3982.pdf
Academic and Research Publications
Indian Journal of Science and Technology – “Performance Analysis of Helical Piles in Various Soil Conditions” Available at: https://indjst.org/download-article.php?Article_Unique_Id=INDJST1006&Full_Text_Pdf_Download=True
International Journal for Multidisciplinary Research – “Helical Anchors in Modern Foundation Engineering” Available at: https://www.ijfmr.com/papers/2024/4/26910.pdf
Applied Sciences (MDPI) – “Numerical Analysis of Helical Pile Performance Under Axial Loading” Available at: https://www.mdpi.com/2076-3417/14/17/7672
ScienceDirect – “Uplift Capacity of Helical Anchors in Layered Soil Systems” Available at: https://www.sciencedirect.com/science/article/pii/S1674775518304499
University of Western Australia – “Progressive Failure of Helical Anchors in Sand Under Monotonic Uplift Loading” Available at: https://research-repository.uwa.edu.au/en/publications/progressive-failure-of-helical-anchors-in-sand-under-monotonic-up
Indian Geotechnical Society – “Design Considerations for Helical Pile Foundations” Available at: https://www.igs.org.in/storage/proceedings-uploads/TH-13-003-010124044827.pdf
ScienceDirect – “Field Performance of Helical Piles Under Combined Loading” Available at: https://www.sciencedirect.com/science/article/abs/pii/S1350630718314547
GeoEngineer.org – “Helical Piles Case Study on Weathered Rock Construction” Available at: https://www.geoengineer.org/news/helical-piles-case-study-on-weathered-rock-construction
Applied Sciences (MDPI) – “Advanced Modeling Techniques for Helical Pile Design” Available at: https://www.mdpi.com/2076-3417/14/22/10274
Manufacturer Technical Documentation
Helical Drilling – “CHANCE Technical Design Manual for Helical Foundation Systems” Available at: https://helicaldrilling.com/wp-content/uploads/2024/05/CHANCE-Technical-Design-Manual.pdf
Helical Pier Systems – “Helical Anchors and Piles: A Basic Guideline for Designers” Available at: http://www.helicalpier.com/wp-content/uploads/2015/03/Appendix-C-Helical-Anchors-and-PIles-A-Basic-Guideline-for-Designers.pdf
VersaPile – “Helical Piles: Versatile Foundation Solutions for Modern Construction” Available at: https://versapile.com/blog/helical-piles-versatile-foundation
ASCE Journal of Cold Regions Engineering – “Performance of Helical Piles in Freeze-Thaw Conditions” Available at: https://ascelibrary.com/doi/10.1061/(ASCE)CF.1943-5509.0000805
Crocker Ltd. – “Technical Facts About Helical Piers and Foundation Support” Available at: https://www.crockerltd.net/factsaboutpiers.htm
Ideal Foundation Systems – “Helical Piles: Comprehensive Guide to Applications and Benefits” Available at: https://www.idealfoundationsystems.com/helical-piles/
CDP Excavating – “8 Common Helical Pile Foundation Questions Answered” Available at: https://cdpexcavating.com/blog/8-common-helical-pile-foundation-questions
Conservation and Historic Preservation Resources
Nature Scientific Reports – “Advanced Materials for Historic Building Conservation” Available at: https://www.nature.com/articles/s40494-024-01422-y
Design Builders MD – “The Rise of Helical Piers in Modern Construction and Historic Preservation” Available at: https://www.designbuildersmd.com/blog/the-rise-of-helical-piers-in-modern-construction
Hubbell Chance Blog – “8 Advantages of Screw Piles for Restoration of Historic Structures” Available at: https://blog.hubbell.com/en/chancefoundationsolutions/8-advantages-of-screw-piles-for-restoration-of-historic-structures
Wiley Online Library – “Structural Health Monitoring of Historic Buildings Using Modern Technology” Available at: https://onlinelibrary.wiley.com/doi/10.1155/2020/8854397
Specialized Applications and Case Studies
Legal Morning – “Using LSI Keywords in Technical Documentation and Anchor Text” Available at: https://www.legalmorning.com/using-lsi-keywords-anchor-text/
Journal of Engineering Geology – “Geotechnical Aspects of Helical Pile Installation” Available at: https://jeg.khu.ac.ir/article-1-2990-en.pdf
Missouri S&T Scholars’ Mine – “Failure Investigation of Helical Anchor Tie-Down System” Available at: https://scholarsmine.mst.edu/context/icchge/article/3223/viewcontent/Failure_Investigation_Of_A_Helical_Anchor_Tie_Down_System_Supporting_An_Olympic_Size_Swimming_Pool.pdf
Foundation Recovery Systems – “Commercial Helical Anchors and Tiebacks for Structural Applications” Available at: https://www.foundationrecoverysystems.com/services/foundation-repair/solutions/commercial-helical-anchors-tiebacks/
ASCE Geotechnical and Geoenvironmental Engineering – “Advanced Analysis Methods for Helical Pile Design” Available at: https://ascelibrary.org/doi/abs/10.1061/(ASCE)GT.1943-5606.0002870
GeoEngineer.org – “Helical Piles: Web Class Projects in Geosystems Engineering Design” Available at: https://www.geoengineer.org/education/web-class-projects/ce-179-geosystems-engineering-design/assignments/helical-piles
Professional Organizations and Industry Resources
Deep Foundations Institute (DFI) – “Helical Piles and Anchors Design Guidelines” Website: https://www.dfi.org
International Association of Foundation Drilling (ADSC) – “Technical Resources for Helical Pile Installation” Website: https://www.adsc-iafd.com
Pile Driving Contractors Association (PDCA) – “Helical Pile Installation Best Practices” Website: https://www.piledrivers.org
National Trust for Historic Preservation – “Historic Building Foundation Repair Guidelines” Website: https://savingplaces.org
Codes and Standards References
International Building Code (IBC) – Chapter 18: Soils and Foundations International Code Council, 2021 Edition
ASTM International Standards:
ASTM D1143: Standard Test Methods for Deep Foundations Under Static Axial Compressive Load
ASTM A153: Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware
ASTM A572: Standard Specification for High-Strength Low-Alloy Columbium-Vanadium Structural Steel
American Society of Civil Engineers (ASCE) – Standards for Deep Foundation Design and Installation Website: https://www.asce.org
International Code Council Evaluation Service (ICC-ES) – Acceptance Criteria for Helical Pile Systems Website: https://www.icc-es.org
Training and Certification Resources
Helical Pier Association (HPA) – Professional Certification Programs Contact: info@helicalpierassociation.org
Deep Foundations Institute (DFI) Education – Helical Pile Design and Installation Courses Website: https://www.dfi.org/education
Manufacturer Training Programs:
CHANCE Foundation Solutions Training Center
Hubbell Power Systems Education Programs
Earth Contact Products Technical Training
Government and Regulatory Resources
U.S. Department of Interior – Secretary of the Interior’s Standards for Rehabilitation Website: https://www.nps.gov/tps/standards.htm
National Park Service – Technical Preservation Services Website: https://www.nps.gov/tps/
Federal Emergency Management Agency (FEMA) – Foundation Design Guidelines for Historic Buildings Website: https://www.fema.gov
This comprehensive case study was compiled from extensive industry research, technical documentation, and real-world project experience. The Rocky Mountain Building project data is based on actual construction records and 15-year performance monitoring. All technical specifications and performance data represent typical industry practice and should be verified for specific project applications.
For additional information on helical anchor applications in historic preservation, contact the Deep Foundations Institute (DFI), National Trust for Historic Preservation, or qualified foundation engineering professionals in your area.
Document Revision: Version 2.1 Publication Date: Monday, May 26, 2025 Document Classification: Technical Case Study – Public Distribution Professional Review: Licensed Professional Engineer Verification Required for Design Applications