Anti-Buoyancy
CHANCE® Helical Anchors and MANTA RAY® earth anchors provide reliable anti-buoyancy anchoring for pipelines, tanks, vaults, and other below-grade structures in high groundwater. Both systems install with small equipment, create minimal disturbance, avoid large excavations and spoils, and can be verified at the time of installation—an efficient alternative to concrete deadmen or added ballast.
CHANCE® Helical Anchors (Bearing-Mode Uplift Resistance)
Helical anchors resist uplift by advancing helical bearing plates into competent soils, relying on soil bearing rather than friction or added structure weight. They install cleanly, require no concrete or cure time, are not impacted by high water tables, and can be loaded immediately. Capacity is correlated to installation torque, with optional proof testing. Helicals can also be removed or extended if the project requires it.
Benefits of CHANCE® Helical Anchors for Anti-Buoyancy
- No concrete; no cure time
- Minimal disturbance and no spoils
- Not impacted by high groundwater; limited de-watering
- Immediate loading with torque-correlated capacity
- Removable/extendable when specified
MANTA RAY® Earth Anchors (Percussion-Driven, Proof-Loaded)
MANTA RAY® anchors are percussion-driven with compact tools and then proof-loaded at lock-off to confirm capacity on site. They are well-suited for light to moderate uplift demands (soil/depth dependent), tight-access locations, and rapid mobilization—delivering efficient buoyancy control without large excavations or spoils. Note: MANTA RAY® anchors are not removable.
Benefits of MANTA RAY® Anchors for Anti-Buoyancy
- Fast installation with small equipment
- Proof-load verification at lock-off
- Minimal disturbance; no spoils to haul
- Effective in limited-access and high-water-table conditions
- Not removable
When to Use Each Product
- Use CHANCE® Helical Anchors when you need bearing-mode uplift resistance, torque-correlated design, immediate loading, and potential removability.
- Use MANTA RAY® earth anchors when the project calls for quick, proof-verified installs, small-equipment access, and light to moderate uplift demands.
Frequently Asked Questions
Do I need to de-water for installation?
Generally, no. Both systems install with small equipment and avoid large excavations, reducing or eliminating de-watering compared to concrete deadmen.
How is capacity verified?
Helical anchors use installation torque correlation (with optional proof tests). MANTA RAY® anchors are proof-loaded at lock-off to confirm performance on site.
Are the anchors removable?
Helical anchors can be removed or extended when specified. MANTA RAY® anchors are not removable once installed and proof-locked.
When do engineers prefer helical anchors?
When projects require stringent testing, engineering sign-off, or detailed design documentation, helical anchors are often preferred due to their torque-correlated installation and well-established design methodology.
Why use helical or MANTA RAY® anchors instead of concrete deadmen?
Unlike concrete deadmen or added ballast, helical and MANTA RAY® anchors require no excavation, no spoils, and no cure time. They install quickly with small equipment, are not impacted by groundwater, and provide immediate, verifiable capacity. This reduces labor, mobilization, and cleanup costs while delivering predictable performance for buoyancy control.
Project Support
Selection depends on uplift loads, soils, access, groundwater, and testing requirements. We support the engineer of record with product data, preliminary capacity guidance, and proof-testing recommendations. Ask an Engineer or Request a Quote.
Your Solution for Other Tiedown Applications
CHANCE® and MANTA RAY® anchors are also used wherever uplift or marine restraint is critical:
- Guy Anchoring — towers, poles, and guyed structures
- Mooring — floating docks, barges, and marine structures
Want to learn more? Visit our Helical Anchor and MANTA RAY® Earth Anchor pages.