Market-leading grouting solution for the first operational French offshore wind project

PROJECT OVERVIEW

EDF-led wind farm St. Nazaire produced the first megawatt-hours from French offshore wind in June 2022. Acteon is proud to have been involved in this significant project by providing grouting services for the foundations through LDD, a marine foundations brand in Acteon’s Engineering, Moorings and Foundations division. LDD provided skilled personnel and services for grouting of the 80 monopiles in position along with the transition pieces to monopile connections through a contract with DEME Offshore.

THE CHALLENGE

DEME Offshore was drilling sockets at 7.7m diameter for the monopiles to be installed into the construction design. DEME requested a grouting spread capable of mixing and pumping bulk supplied material to grout at a rate of 100m3/hour as well as bag supplied material for the MP/TP connection.

CUSTOMER GOAL

DEME Offshore’s goal was to pump the required volumes of grout into the drilled sockets as quickly as possible to reduce vessel time, whilst adhering to the project quality and safety specifications, because a lot of the grouting was on the vessel’s critical path.

OUR SOLUTION AND ITS COMMERCIAL BENEFITS TO THE PROJECT

Market-leading services and integrated solutions

• LDD designed, built and delivered a bespoke grout mixing and pumping system within eight months from contract award to meet the output requirements of DEME Offshore, exceeding the output of existing equipment which was 25m3/hour.

• The batch mixing technique used on the new system provides mixed grout with exceptionally high-quality control standards due to the precision of grout weight and water volume measuring.

• The system can mix bulk and bag supply grouts in the same configuration allowing for a wide range of different grout materials to be used on the same project.

Work at scale with a proven track record for delivery

• LDD has an extensive track record of grouting on offshore windfarms including SeaMade, where significant time and cost efficiencies were achieved; this was one of the reasons that DEME selected LDD for this project.

We optimise the project to increase commercial value

• The innovative new system exceeded the output rate of LDD and other grouting equipment on the market, allowing the customer to minimise vessel time and cost.

• LDD provided multi-skilled technicians to meet the crew rotation and quarantine demands of working offshore in France throughout the project duration.

• Management of grouting system design and supply simplified the supply chain.