Reviving The Nashville Wharf: Transforming 1,500 Pile as a US South Coast Port

WHARF-SUPPORTING PILES DETERIORATION

By the time rehabilitation planning began, the wharf’s supporting piles were experiencing significant deterioration. Years of exposure to water, fluctuating tides, and environmental conditions had resulted in severe pitting corrosion along substantial lengths of the steel piles. In many cases, corrosion extended over 13 feet vertically, with pitting depths reaching up to a quarter of an inch. This degradation had progressed to the point where steel loss exposed the internal concrete fill, raising concerns about both structural capacity and long-term performance. Compounding the difficulty, much of the corrosion extended below the mudline, making it harder to access and repair.

Beyond the structural concerns, the port facility faced operational and economic pressures. The Nashville Wharf is a critical asset, supporting ongoing logistics and trade, and could not be taken out of service for an extended period. At the same time, the state had clear ambitions to ensure the facility could continue supporting economic growth well into the future. Previous repair attempts using alternative FRP jacket systems had failed, which heightened the need for a reliable, thoroughly proven solution. The challenge was not simply to repair what was damaged, but to do so in a way that ensured durability, minimized disruption, and avoided the far greater cost of full replacement.

A COMPLEX REHABILITATION PROJECT

For Fyfe and the project team, the complexity of the environment introduced a combination of technical and logistical challenges. The worksite was defined by its exposure to tidal river conditions, where water levels and currents constantly shifted. Many of the damaged zones were located underwater or beneath the mudline, requiring crews to work in conditions that were both physically demanding and technically restrictive. High humidity, elevated temperatures, and frequent exposure to moisture created additional constraints, particularly when working with materials that typically require controlled conditions to cure properly.

Accessing the piles themselves presented another layer of difficulty. The team had to navigate soft mud conditions that required compaction before work could safely proceed, and in many cases, excavation was needed to reach the footing elevations of the piles. Temporary working platforms, scaffolding systems, and lighting had to be installed throughout the site, all while coordinating material transport in an active port environment. Every step of the process had to be carefully planned to avoid disrupting ongoing operations.

From a technical standpoint, the team faced critical decisions around material performance and installation methodology. The selection of the appropriate epoxy system was particularly important, as traditional systems are not designed to cure effectively in wet or underwater conditions. Maintaining consistent quality across such a large-scale installation also posed a challenge, requiring strict adherence to quality assurance and quality control procedures.

CAREFULLY ENGINEERED SOLUTIONS

To meet these challenges, Fyfe and PCL Construction implemented a carefully engineered solution built around the LOCTITE Tyfo FRP system. A key decision was the use of the LOCTITE Tyfo SW1S epoxy, which is specifically designed to cure even when exposed to water. This capability proved essential given the realities of the marine environment. Combined with LOCTITE Tyfo SCH-41 carbon fiber fabric, the system provided both corrosion protection and structural strengthening.

The repair process itself followed a structured, coordinated sequence. Work began with site preparation, including the development of safe access and the stabilization of working surfaces through mud compaction and excavation. Once access was secured, scaffolding, mats, and lighting were installed to enable safe and efficient operations. Materials were staged and transported into position, and saturation equipment was set up to ensure consistent application of the FRP system.

Surface preparation was carried out, ensuring the piles were properly cleaned and ready to receive the repair materials. The team then applied a combination of neat and thickened epoxy before installing the saturated carbon fiber wraps. Each pile received multiple layers, applied to achieve the required structural performance. A final coating was applied to protect the system, and quality control inspections were conducted throughout the process. Verification testing in accordance with ASTM standards provided additional assurance of system performance.

Despite the complexity, the team achieved a steady production rate, completing approximately four fully wrapped piles per day. The work was carefully scheduled to align with the drier months in the US South Coast, maximizing efficiency and minimizing weather-related disruptions.