N’Kossa Barge

When it left the port of Marseille, where it was built, in the spring of 1995, the N’Kossa barge was the largest pre-stressed concrete barge in the world. This technical achievement required a year and a half of engineering studies and eight months of construction works.

Custom-designed to accommodate the world’s largest floating hydrocarbon production unit, it is anchored at a depth of 170 metres off the coast of the Republic of Congo. Its design called for innovative approaches and methods that had never before been used in this context.

Some were inspired by the containment systems of nuclear power plants, others by shipbuilding, all to ensure the safety and watertightness of the structure—particularly against collisions on the outer hull—as well as its durability in the marine environment for a theoretical lifespan of 30 years.