Testing of Marine Fenders

Abstract: Fender testing is a crucial aspect of the industry, which has been established for many years. The PIANC WG33 "Guidelines for the Design of Fenders" (2002) and the ASTM F2192 "Standard Test Method for Determining and Reporting the Berthing Energy and Reaction of Marine Fenders" (2022) have already recognized their importance.
The recently published PIANC WG211 "Fender Guidelines" (2024) take a significant step forward by introducing new forms of testing and providing better protocols to ensure consistent testing. The PIANC WG211 guidelines consider three types of testing: Fundamental Testing, Type Approval Testing, and Verification Testing. Additionally, they introduce new terminology, including Fender Base Performance, Design Deflection, Stabilizing Compression Cycles, and Thermal Stabilization.
To ensure the credibility of fender testing, it is essential to demonstrate that the physical properties test results and the type approval test results are relevant to the actual fenders supplied. Thermogravimetric Analyses (TGA) testing can help establish this by showing that the chemical composition of the compound used for testing is similar to the chemical composition of the actual fenders. This avoids the use of high-quality compounds for testing while employing a different (low-cost) quality compound for the actual fenders.
Designers and authorities must be aware of the changes and the content of PIANC WG211 Chapter 10. Ideally, specifications writers should adopt the new PIANC guidelines into their specifications.
The industry will need to adopt the new PIANC Guidelines as soon as possible. PIANC WG211 Chapter 1 states, "Since the changes are quite substantial, there is a transition period between WG 33 and WG 211 to reorganize Fender suppliers' catalogs according to the new guidelines, which is expected to require a significant amount of type approval testing." The transition period ends on 1-5-2026 (two years after the WG 211 guideline publication). Designers can start using the new guidelines but should be aware of what they are specifying for deliveries before this date.
However, suppliers adopting the new PIANC WG211 guidelines cannot guarantee reliable Fender performance results from suppliers. Recent research by Politechnico di Milano shows that 30% of fenders tested by an independent body do not meet the claimed performance. Therefore, independent testing is critical to ensuring performance and driving the industry to better practices. Generally, two forms of independent testing are recognized: Independent testing at a third-party facility or a third party with verification equipment that works independently from the supplier's equipment.
Independent testing involves three stakeholders: Manufacturers, authorities and the 3rd parties. Its important that these stakeholders work together and understand the technical possibilities of independent testing and potential impact on the delivery schedule.

How does this project / topic contribute to the advancement of the industry and profession?: Testing of fenders has been a common practice. However, testing traditionally happens at the supplier under the suppliers control. Even for an independent 3rd partly witness it will be difficult to impossible to truly verify the performance of the fender. Various cases and a paper from Politecnico Milano show that fender performance is not reliable at all, hence why looking into independent testing is critical for the advancement and professionality of this industry.

Does the project / topic implement new and innovative techniques, materials, technologies, and delivery methods?: The topic will cover the latest in industry standard and guidelines (PIANC WG211) as well as new forms of testing such as fatigue testing and shear / compression testing and the importance of it. Also linking the sample testing to the actual product via Thermogravimetric Analyses (TGA) testing is new development in the industry.

What was the most challenging aspect of your project / topic and how did you handle it to ensure success?: Providing unbiased and factual information that many of the fenders supplied do not really meet the performance has been a challenge for various reasons. Fenders are not often independently tested and even when they are independently tested the results stand on their own and without considering various test data from various tests a general conclusions can not be drawn. However recent independent studies have provided these insights now.

Who is the target audience for this paper?: Both Port Authorities and Consultants will benefit from this paper. They will be provided insights of the new PIANC WG211 chapter 10 “Testing of Fenders. It will also show them the importance of considering independent fender verification testing to ensure the fenders truly meet the performance over its full service life.