Denmark's Rohde Nielsen Completes Caisson Filling Work for Breakwater at Port of Bilbao

en.Wedoany.com Reported - On November 11, Danish marine engineering contractor Rohde Nielsen announced that it had completed the caisson filling work for Phase II of the central breakwater project at the Port of Bilbao, Spain, having delivered approximately 248,000 cubic meters of dredged material into the caissons in total. The work was carried out by the company's trailing suction hopper dredger Njord R, which used its independently developed side-discharge pipe system to convey sand collected offshore into the interior of the caissons.

The construction adopted a side-discharge pipe delivery method, with the dredger feeding sand directly into the caissons through pipes along the vessel's side. Compared with conventional filling methods, this system can control the delivery position of the material and the filling process, reduce the dispersion of sand, and enable a uniform filling structure to gradually form inside the caissons. The operation involved 15 reinforced concrete caissons and is a key construction step for the port's new vertical quay structure.

The caissons were manufactured on floating platforms and, once completed, towed by water to their designated positions, where they were sunk onto pre-treated foundations by injecting water into their internal compartments, after which the compartments were filled with sand. Once filling is complete, the caissons form the main structure of the quay wall, and subsequent work remains to be carried out, including backfilling behind the quay, construction of the superstructure on both the landward and seaward sides, extension of the drainage system, and installation of port equipment.

Phase II of the central breakwater project at the Port of Bilbao is being built by a consortium led by Spanish engineering and infrastructure company Sacyr, with a contract value of EUR 55.2 million. The scope of work includes the construction of the new A3 quay and the extension of the existing A4 quay. The A3 quay has a berth line of 664 meters, and the A4 quay is being extended by 347 meters; both quays are designed with a water depth of 21 meters, adding a total of 1,011 meters of berth line.

Upon completion, the project will add 31.2 hectares of port area. According to the construction schedule, Phase II is planned for completion in the first quarter of 2027, by which time the infrastructure construction on the east side of the central breakwater at the outer port of Bilbao will be completed.