Grouting for long-term operational efficiency of wind farms

Choosing the optimal grouting solution for the foundation

The choice of grout material depends on factors such as specific design requirements, site conditions, and engineering preferences.

Commonly used grouts include Portland cement, pre-blended material, and lightweight filler material. Different grout types may be used in various sections or layers of the foundation, based on their specific properties and performance characteristics.

High-performance blended cementitious grouts are commonly used due to their excellent bonding characteristics and resistance to harsh marine environments. This type of grout is designed to withstand the extreme conditions encountered offshore, including saltwater corrosion and fluctuating temperatures. However, neat Portland cement grout is just as effective in some foundations and has several advantages from an installation and cost point of view.

Once the material has been selected, the mixture is carefully prepared to achieve the desired consistency, ensuring proper flow and filling of voids. During the process, the pressure, flow rate, and quality of the grout must be closely monitored to ensure uniformity and prevent any potential issues.

A foundation to last a lifetime

Where a foundation design considers a grouted structural connection, the grouting ensures the long-term stability of the wind farm foundations by forming part of the connection between the wind turbine and the ground.

While grouting plays a crucial role in the construction phase, ongoing maintenance is equally important to preserve the integrity of the foundation. Unlike with bolted connections, once the grout is in place it does not come out and does not need to be replaced during the lifetime of the turbine; in fact, it gets stronger over time. However, regular inspections of other parts of the foundation and the rest of the wind turbine should be performed to monitor loads, vibration, fatigue stress, temperature, and corrosion to allow for timely repairs and reinforcement if necessary. Grout can be used as a repair tool for areas unrelated to the initial grouted pile connection. Repair and strengthening options include member filling, grouted clamps and cable supports. These services are offered as part of Acteon’s operations, maintenance and integrity package. We develop site-specific, optimised O&M strategies including inspection, survey, monitoring, repair, and maintenance requirements to ensure that subsea assets safely fulfil their design life.

To support the continued growth of offshore wind worldwide, Acteon’s marine foundations segment is investing in research and innovation to optimise offshore installation and grouting techniques and materials. By doing so, we can harness the power of offshore wind to its fullest potential, enabling the energy transition for our customers.