References

In 2006, EDF initiated the construction of the EPR nuclear power plant in Flamanville, France (50). TERRASOL intervened within the framework of a G3 mission on earthworks and retaining structures preparation works. This included more particularly:

• nailed/bolted slopes in a highly fractured, sometimes altered, rocky context ;
• sheet-pile gabions ;
• anchored soldier-pile walls ;
• traditional retaining walls.

Some parts of these structures are located below sea level.

In terms of geology, the project is located at the periphery of the Flamanville granite batholith and overlaps hornfels, highly metamorphised terrains, characterized by a very high abrasivity. The geological monitoring during the earthworks enabled to optimize the embankment reinforcements and the drainage systems according to the fracturation observed, but also to adapt the construction techniques.

Some sensitive structures were subjected to reinforced monitoring, with the definition of deformation thresholds and interpretation of measurements.

Terrasol’s achievements:

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• Earthworks geological monitoring (G3 mission)
• Reinforcements optimisation