Abstract: Protective barrier consisting of at least two ballastable elements (3, 4) adapted to surround at least partially the work to be protected (1).The height of the individual elements is greater than the water depth. The elements comprise a connection device permitting the structural continuity of the elements after assembly. The protective barrier is entirely independent of the work to be protected. The positioning of the elements around the work is effected by means of a positioning system provided in the sea bed and/or the individual elements of the protective barrier.

Abstract: The platform comprises an annular truncated cone of concrete which constitutes the main resistant element of the platform and is designed to take the thrust of ice, and a cylindrical steel part housed inside the annular truncated cone. Watertight passages parallel to the generatrices of the cylindrical wall are provided to house piles in the peripheral ring, close to the wall. A watertight passage well is provided in the cylindrical steel part for the passage of the drill pipes. A circular running track is provided for gantry cranes used for piles handling. The platform has two drilling rigs placed on one half of the platform and able to work simultaneously.

Abstract: An oscillatable marine installation comprises a concrete and steel lattice shaft supported by means of a demountable pivot joint on a base fixed to the-sea-bed and including an anti-torque device. The pivot joint is made up of three parts: a casing fixed to the shaft, a part-spherical housing fixed to the base, and a pivot member. The pivot member has an upper part cooperating with the casing, a flange which can be fixed to the casing, and a lower part-spherical part housing which supports a resilient assembly and a bush fixed on the housing. The anti-torque device comprises a universal joint, concentric with the pivot joint. Two opposite pivots of the crosspiece of the universal joint are supported by the lower part of the shaft and the other two pivots by the base. At least two opposite pivots have damping devices and the pivots supported by the base are mounted on supports the height of which can be adjusted.

Abstract: A mooring assembly connects a submarine conduit to another conduit of a pipe-line or fixed installation. The mooring assembly comprises a mooring frame, a movable mooring arm and a mooring head. The conduit is to be connected to the mooring head having a lateral passage through which the end of the conduit may extend. The movable mooring arm is pivotally mounted on the mooring frame. One end of said other conduit is fixed on the pivot axis of the mooring arm. A connecting pipe connects the end of the submarine conduit to the end of the other conduit. A coupling assembly at the outwardly extending end of the mooring head pivotally connects an axial extension of the end of the conduit to be connected to the mooring head.