Technical Primer: What is Bollard Verification?
A marine bollard is not simply a steel fixture attached to a dock. It’s a structural load-transfer assembly: the cast steel body, the anchor bolts, and the reinforced concrete foundation acting together as one system.
Verification testing confirms the entire assembly can reach its rated capacity without permanent deformation, displacement, or substrate damage.
In short: we’re validating the full load path.
Why Testing Is Necessary
Mooring loads are dynamic and aggressive. As vessels like offshore wind Service Operation Vessels (SOVs) grow larger, they impose steeper mooring angles and higher windage loads.
- The Fatigue Factor: Constant-tension winches can keep bollards under sustained high stress—not just cyclical loading.
- The Failure Mode: Failures typically occur in the substrate—bolt shear from corrosion, bolt elongation, or concrete cracking/spalling under combined shear + uplift.
- The Consequence: A bollard failure is catastrophic. Stored energy can turn hardware into a projectile hazard.
Test objective: confirm rated performance with no permanent set and controlled displacement behavior.
The Challenge: Critical Infrastructure for a Green Future
At the South Brooklyn Marine Terminal (SBMT), verification was required for 16 newly installed bollards, each rated for a Safe Working Load (SWL) of 100 Metric Tons (approx. 220,000 lbs).
Engineering Constraints
- Exert 110% of SWL: Apply ~242,000 lbs without damaging a new quay wall.
- Simulate real vectors: Replicate vertical angles up to 30° (uplift + shear interaction).
- Zero failure tolerance: Active construction zone + controlled stored-energy hazard management.
The Engineering Solution: Two Test Paths
Atlas Anchor developed two methodologies to solve the force-generation problem—giving the client flexibility between precision science and heavy logistics.
Option 1 — Precision Engineering
Partner: Bollard Proof Ltd (United Kingdom)
- 125-ton hydraulic test rig anchors directly to the quay (no vessel-motion variables).
- Angle simulation up to 30° vertical to capture uplift + shear.
- Displacement tracking captures micro-movement in bolts and substrate.
Option 2 — Marine Heavy-Lift
Partner: Madeline Marine, Inc. (New York)
- Spud barge + winch system using calibrated inline dynamometry/load cells.
- Efficient along a quay line for repeated shear verification across multiple bollards.
- Local mobilization reduces logistics complexity and cost drivers.
The Testing Procedure: Anatomy of a 100MT Pull
Generating 100 tons of tension creates a significant stored-energy hazard. The protocol below controls risk while producing engineering-grade data.
Step 1 — Setup & Exclusion
Establish snap-back zones. Route load + displacement data to remote telemetry outside the hazard line.
Step 2 — Incremental Loading
Apply staged loads (10%, 25%, 50%, 75%) to verify linear elastic response and stop if displacement becomes non-linear.
Step 3 — Peak Hold at 110%
Hold 110% SWL (110 MT) for ≥10 minutes to identify creep and slow substrate movement.
Step 4 — Controlled Release
Release gradually and confirm return-to-position with no permanent deformation or unacceptable displacement.
The Outcome
- Verified capacity: Protocol designed to confirm 100MT SWL for next-generation vessels.
- Deflection data: Engineering-grade reporting on bollard + substrate behavior under load.
- Technical authority: Documentation aligned with rigorous stakeholder expectations.
Takeaway: A proper regimen doesn’t just check if the bollard stays in the ground — it verifies the physics of the entire assembly: bolts, concrete, and steel.
Technical References & Standards
- UFC 4-159-03: Mooring design guidance and hardware capacity assumptions.
- OSHA 1926.251: Rigging equipment requirements for handling systems.
- ASTM E74: Calibration of force-measuring instruments.
- ASTM E4: Force verification of testing machines.
- ACI 318: Structural concrete requirements relevant to anchorage behavior.
Does your project require engineering-grade verification?
If you want testing support, reach out—our team can help with procedures, execution, and reporting.
Contact Us
We'd be happy to hear from you! Please fill out the form below and someone from our team will be happy to get back to you as soon as possible.
"*" indicates required fields