Fort Boyard, a scale model to save the monument turned TV game from the fury of the ocean

The future of Fort Boyard , the French military fortress built in the sea on the Atlantic coast, a jewel conceived since the time of the Sun King, and built in the following centuries, but today famous mainly thanks to a television program, will be played out at least in part in Belgium. There, in fact, a team of university researchers has analyzed the effects of wave motion on the building, using a miniature replica.

The scenario was set up in a research center in Ostend, effectively transformed into a hangar capable of housing a pool where artificial waves are created. In the center of this “pool” a miniature of the concrete was created. Reduced to one thirtieth of the actual size, the model is a very close replica, with its rounded ends and the openings exactly (in proportion) spaced from each other, on three floors.

Solidity, structural stability, resistance to erosion and submersion: the tests carried out by Belgian coastal and maritime engineering specialists are part of the vast renovation planned for 2028. They were requested by the French public works company ETPO (Spie Batignolles group), engaged in this adventure with the French department of Charente-Maritime, owner and headquarters of the site.

The advantages of the 3D model

Their particularity is that they are based on a 3D replica of the building under examination, a rare fact even in this type of study. “We normally use 2D models, with simplified geometric shapes for cost reasons. It is nice to have the fort in our basin and to contribute to this renovation of a historic building,” Peter Troch, one of the heads of the research project, explained to the Agence France Presse. “We are generating storm waves in real conditions and these tests will allow us to improve the initial design of the fort, as it was conceived for this renovation.”

It is a form of validation of the project before the start of the works", continues the professor from the University of Ghent, one of the partners of the Ostend centre, launched in 2023 (Coastal & Ocean Basin, COB).

A significant part of the work concerns the two ends of the fort, where the project includes the reconstruction of the protective works that have disappeared over the decades and centuries, overwhelmed by the aggressions of the Atlantic. This concerns, at the front, the spur that points towards the sea, to the northwest, and, at the rear, the port - or "landing port" - through which visitors will be able to disembark from 2028, albeit in favourable weather conditions.

Monitoring the waves

Around the wave pool, technicians monitor the data collected by sensors in the water on a screen, and their attention is focused on the breakwater located in front of the spur. And to what extent it is able to protect the building from the action of storm surges. "With climate change, we are not sure what sea conditions we will have in the future," emphasizes one of the specialists from the University of Ghent.

“If we manage to attenuate the energy of the waves that propagate, we also limit the erosion, which was the main factor in the degradation of the fort,” he adds. Built between 1803 and 1857 between the island of Oléron and the island of Aix, from an idea born none other than the Roi Soleil Louis XIV, a former military structure turned prison, Fort Boyard had fallen into ruin before being classified as a historical monument.

Bought in 1988 by Jacques Antoine, a producer of TV games, it was sold the following year to the department of Charente-Maritime for a symbolic franc. It is up to the latter to maintain it. Currently inaccessible to the general public, the building continues to host every spring - from March to the end of June - the filming of the TV quiz that made him a world star. The show "Fort Boyard", launched in 1990 in France, has given rise to more than 1,500 episodes in about forty countries. The renovation work, which will begin this summer, is estimated at 36 million euros, excluding taxes. Three-quarters of this amount has already been financed. And to raise the remaining nine million, an appeal for donations was launched in mid-December, banking on the strong reputation of the place.