Sheet pile protection

Sheet piling is a steel section used to support the backfill of harbor quays. They are used for both flat and discontinuous-walled quays.


Like any metal structure immersed in a saline environment, metal sheet piling is subject to corrosion. When they are not protected by an anti-corrosion coating or by effective cathodic protection, corrosion occurs on the metal structures, which can cause significant structural damage over the long term: perforations, loss of thickness, leakage of fine particles…

If the sheet pile no longer has sufficient residual thickness, the metal sheet pile curtain may have to be replaced.

This will have serious consequences on :

  • the harbor activity
  • the marine environment
  • the client’s budget


To prevent corrosion and/or limit its spread, Seacure uses the GEOCORAIL process to create a natural rock coating on metal sheet piles. This solution consists of two phases:

Phase 1 – Polarization: To create the rock coating, the metal sheet pile is electrically connected using the GEOCORAIL process, and subjected to an imposed current cathodic protection derivative for around 24 months. The development and propagation of corrosion is then halted.

Phase 2 – Operations : Once a suitable GEOCORAIL coating has been obtained, the electrical system is shut down. The GEOCORAIL coating then acts as a “plaster” on the metal sheet piling.

Thanks to its natural properties, GEOCORAIL significantly reduces :

  • the rate of corrosion of the sheet pile
  • provides an additional protective layer for the quay
  • limits water infiltration
  • limits the possible appearance of breaches and cracks
  • increases structural strength



Masonry quays are unique in that most of them are historic harbor structures made of stone and stone facing.


Over time and as a result of exposure to the sea, these masonry structures can suffer a number of alterations:

  • Subsidence and deterioration of masonry paving
  • Widespread erosion of joints
  • loosening of coping and/or facing stones
  • Scouring at the foot of the wall…

If left untreated, these disorders can, in the long term, jeopardize the structural integrity of the construction.


To reduce the risk of stone loosening, Seacure uses the GEOCORAIL process to create a rock lining on the masonry structure – GeoDock. This solution is divided into 4 phases:

  • Phase 1: filling voids and cavities resulting from stone loosening with pozzolanic stone
  • Phase 2: Fixing avalanche protection nets or expanded metal plates to the area at risk.
  • Phase 3: Polarization of metal structures for around 24 months using the GEOCORAIL process, to obtain a rock coating of significant thickness.
  • Phase 4: once the GEOCORAIL coating has been obtained, the GEOCORAIL process is stopped. The rock layer provides additional protection and support for the masonry platform. The risk of stone loosening in the treated area is reduced, thus lowering the risk of water infiltration and leakage of fine particles.


Quays scour protection system

Scouring at the foot of port quays is a frequently encountered phenomenon. They consist of the formation of a cavity under the infrastructure, caused by marine currents, the tide or the propulsion systems of docked ships.


Where scouring is significant, the overall structural strength of the quay may be compromised. Risks of failure, instability or slippage of the structure may arise.


With the GEOCORAIL process, Seacure has developed a preventive solution to prevent and limit the spread of scour at the foot of structures. This solution is divided into 4 phases:

  • Phase 1: design and dimensioning of the anti-scouring system according to the configuration of the site and the type of ships docked.
  • Phase 2: installation of a semi-rigid mattress made of a polarizable geotextile and ballasted with sediment. The mattress is fixed to the vertical wall of the quay and unrolled on the seabed. Once deployed, the mattress follows the curve of the seabed where the scour occurs.
  • Phase 3: Polarization of the semi-rigid mattress using the GEOCORAIL process for around 24 months. A protective rock layer is created on the upper part of the mattress flanges. The junctions between each flange will not be coated with GEOCORAIL, to allow the anti-scouring system to follow the evolution of the seabed over time.
  • Phase 4: Once the GEOCORAIL coating has been applied, the GEOCORAIL process is stopped. The new semi-rigid GEOCORAIL wall limits water infiltration into the quay at the bottom, and shifts the risk of scouring to the end of the mattress opposite the quay. This reduces the risk of scour expansion.


In the case of slight scouring resulting from small-scale natural phenomena, the deployment of an expanded metal grid instead of a semi-rigid mattress may be preferred.



GeoFlow is designed to protect a metal structure when immersed in a marine environment, and to prevent corrosion.


In a harbor, several structures of different metal composition coexist (steel or aluminum ship hulls, aluminum pontoons, lock gates or steel sheet piling, etc.) cohabit and are subject to natural oxidation. When metal structures of different composition are in direct contact, unintentional electrical currents can be created, accentuating the corrosion phenomenon.

Eventually, this corrosion can reduce the residual thickness of the metal framework or create perforations in the structure.

It is therefore essential to protect immersed, or in tidal zones, metal structures from corrosion.


Cathodic protection by galvanic coupling (sacrificial anodes)

Sacrificial anodes are applied to the metal structure to be protected. The anodes are made of less “noble” metals than steel, such as zinc or aluminum/zinc/indium alloys, and have a lower electronegative potential than steel. When the anode comes into contact with the element to be protected, an electric current is generated, lowering the electronegative potential of the steel and consuming the anode. Corrosion is thus halted.

Once sized and installed, cathodic protection is self-sufficient. In most cases, the lifetime of the installation is 15-20 years.

Seacure provides the design, sizing and on-site installation of this cathodic protection in accordance with NF EN ISO 15257:2017.


Impressed current cathodic protection 

Sacrificial anodes are replaced by inert anodes, which do not dissolve in the marine environment. The protective current is supplied by an electrical generator placed between the anode and the metal structure to be protected. Once sized and installed, this cathodic protection has an unlimited lifespan and can be remotely monitored.

Coated with precious metals and associated with the electrical generator, the anodes used do not dissolve in the marine environment. As a result, no heavy metals are released into the ecosystem, and the environmental impact on biodiversity is reduced.

Seacure provides for the design, sizing and on-site installation of this cathodic protection system, in compliance with NF EN ISO 15257:2017.



Inspections and harbor works

Thanks to its expertise in underwater work and its material resources, Seacure also provides the following services in Mediterranean harbors :

Inspection and diagnosis :


  • Existing cathodic protection
  • Harbour quays: degraded metal sheet piling, damaged masonry quays, etc.
  • Low-impact mooring lines


Installation and/or replacement of :

  • Low-impact anchors and mooring lines
  • Traditional anchors and mooring lines: anchor bolts, anchor chains, etc.
  • Beaconing systems
  • Floating pontoons…



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