Abstract: The invention relates to a U-shaped arrangement of floats which are ballastable and deballastable so as to raise and lower their height in the water. On each parallel leg of the float arrangement, are mounted supporting beams that are movable along their longitudinal axes so that they may extend into the center of the U-shaped arrangement of floats and also be retracted therefrom. The device may be used for lifting and transporting large loads by placing the load in the center of the U-shaped arrangement of floats while the floats are ballasted so that they sit low in the water, extending the supporting beams into the center of the arrangement of floats so that they are underneath the load, and then deballasting the floats so that they rise higher in the water while lifting the load.

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: The invention relates to an icebreaker system for marine platforms wherein the system includes two rings of obstacles: a lower ring and an upper ring fixed around pillars of the platform to be protected. The lower ring has obstacles showing a portion sloping upwardly and rearwardly. The upper ring has obstacles staggered with those of the lower ring and showing a portion sloping downwardly and rearwardly. A ring of obstacles is mounted rotatably and/or movably in the vertical direction. The obstacles are of truncated pyramid shape and asymmetrically shaped in front elevation.

Abstract: The device comprises two concentric swivels, a first or mooring swivel being arranged on the outside of the second or bearing swivel, the second swivel being fixed to the end of a cartridge held in a movable manner in a tube forming a projection at the lower end of the shaft and an extension of an axial passage in the shaft. The cartridge is formed by a cage fitted with openings in which keys are housed. A ring is lowered between the keys and immobilizes them against the wall of the tube which forms an extension of the axial passage in the shaft. The method consists of lowering or raising the cartridge carrying the bearing swivel by means of a set of rods.

Abstract: A flexible joint for connection of two pipes comprises a cup-shaped piece which can be connected to a first pipe, a tubular piece which can be connected to a second pipe, the tubular piece being coaxial with the cuplike piece and being arranged partially inside it, and two flexible spherical rings arranged between the cuplike piece and the tubular piece. The two flexible spherical rings are bolted together and arranged on opposite sides of the center of oscillation, the concave surfaces of the rings being directed towards the center of oscillation and being concentric with respect to this center.

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.

Abstract: A concrete structure for the transmission of loads from the steel lattice tower of a marine platform resting on the sea bed by means of concrete base plates, the lattice tower being made up of tubular members which form bracing joints with the legs of the platform. The structure comprises a cylindrical hollow body forming at least part of a platform leg, and having on the inside enclosed spaces defined by internal walls and by the hollow body wall, and concrete fixing plugs formed within the enclosed spaces and engaged by the ends of the lattice members, the enclosed spaces being in the form of hollow rings or vertical shafts within the hollow body.

Abstract: A platform resting at the bottom of a body of water, including a plurality of longitudinally disposed bays supported by piers each consisting of a small number of transversely aligned posts resting on a common base and each supporting a cross-beam, each bay comprising a framework of longitudinal beams which rest at either end on the cross-beams, and a method of constructing the platform comprising the steps of preparing each pier onshore, transporting it to the installation site and setting it down on the bottom, raising the base at several points and adjusting their heights above the bottom in order to position the base horizontally, securing the base in that position by pouring concrete beneath it, preparing each bay on the shore, transporting it to the installation site and setting it down on two adjacent piers.

Abstract: An assembly for mooring a submarine conduit to a pipeline or a fixed structure such as a storage tank. The assembly comprises a mooring head, a fixed mooring frame and a movable mooring arm. The mooring head is fixed to the end of the conduit to be connected. The mooring arm is mounted on the fixed mooring frame and is effective to receive the mooring head. The mooring arm is displaceable in a horizontal plane on the mooring frame. An end of the pipeline to which the conduit is to be connected is located on the rotational axis of the mooring arm. A junction pipe connects the end of the conduit to the end of the fixed pipeline. A cable attached to the mooring head passes through the mooring arm and is attached to a winch on the surface for drawing the mooring head into engagement with the mooring arm.

Abstract: An assembly for positioning a crane mounted on a support and intended to overhang the platform of a platform structure having a base which rests on the bed of a body of water. The crane is located on the vertical axis of a column offset with respect to a central shaft which carries the platform. The assembly comprises a mobile shaft element contained in the upper part of the offset column and having a base with jacks or a block and tackle permitting its emergence as far as the upper level of the offset column. The lower face of the crane support carries a downwardly extending shaft element which has the same diameter as the mobile shaft element. The two shaft elements are substantially coaxial when the platform is carried on the central shaft so that they may be joined together and raised as a unit.

Abstract: For laying a pipeline on the bed of the sea, a plurality of pipeline sections are successively towed by a tug exerting a traction effort at a point spaced to the rear of the front end of a pipeline section being towed, while another tug exerts a holding effort at a point spaced in front of the rear end, the front and rear ends being maintained near to the surface by a system of floats and trail-ropes and the intermediate portion of the pipeline section being ballasted so as to be supported on the sea bed, whereafter the front end of the pipeline section is welded to the rear end of a preceding section, and so on.

Abstract: For inspecting and maintaining a submerged installation comprising an emergent part such as a platform, such as an artificial island or a submerged reservoir, said emergent part is equipped with a track along which a trolley associated with a diving bell can be circulated.The track is preferably installed under the platform, above the portions of the infrastructure to be inspected.

Abstract: A method of constructing a hollow column for resting on a base on a submarine bed, comprises the steps of simultaneously starting the construction of a number of elements that are to form the column, causing the partly constructed elements to float, finishing the construction of the elements afloat, bringing the elements into the horizontal position and connecting them together to form the column, said elements being provided with impervious closures at each end thereof and an impervious caisson adjacent each end thereof, and those of the closures and caissons not required when the column is placed in position are dismantled.

Abstract: A platform comprises a base structure designed to rest on the bottom of the sea for supporting an industrial or scientific installation above the surface of the water. The base structure comprises a floatable device capable of keeping afloat and means for ballasting the base structure to install the structure on the bottom of the sea. The base structure also includes a shaft in which a hollow element with a water-tight peripheral wall and a water-tight lower end wall, can slide vertically. The element can be temporarily fixed to the shaft. The element forms a float capable of supporting a deck which carries the installations, but is capable of being immersed over at least the greater part of its height. The deck is capable of floating until it is over the top of the element when the element is immersed and has means for fixing it to the top of the element.

Abstract: A coupling system provides a controlled decoupling of interconnected component sections of a marine platform structure less rigid under seismic shock while maintaining sufficient overall ridigity to resist the action of swell. The coupling system comprises rigid interconnecting linkage parts, such as steel supports, and flexible interconnecting members, such as "Neoprene" supports, incorporated in the structure. The rigid linkage parts have a structural ridigity sufficient to maintain the overall rigidity of the platform but are effective to break following a seismic shock. The flexible interconnecting members are held in reserve and arranged to back up the rigid integrating parts. The flexible members have structural characteristics effective to maintain the controlled decoupling of the component sections when the steel supports deform or break. The coupling system providing the controlled decoupling is located at an upper level of the structure, preferably above water level, for ease of repair.

Abstract: A gravity platform for supporting installations above a body of water, comprising a base for resting on the bed of the body of water, a structure secured to the base and rising vertically therefrom, a bridge provided with float means, and means enabling the bridge to be displaced along the structure, the base consisting essentially of a slab provided with stiffeners, such as a circular wall and diaphragms, essential for its mechanical strength, the structure forming a hollow column, impervious or not, rising from the middle of the platform, and the float means consisting of an impervious shell formed around the hollow column at the lower part at least of the bridge and forming, possibly with said hollow column, if it is impervious, a float the buoyancy of which is sufficient to support the assembly of the platform and its installations.

Abstract: A device for positioning a pipeline intended to rest on the bottom of the sea or of a body of water. In order to present a resistance to the drifting of the pipeline by the action of cross-currents, the pipeline is provided with a plurality of support members suitably distributed along the pipeline and extending in a direction generally parallel to the vertical plane containing the longitudinal axis of the pipeline. The support members project below the pipeline towards the bottom and are deformable in the vertical plane by the reaction of the bottom on the support members, but are transversely rigid.

Abstract: For laying a pipeline on the sea bed to interconnect first and second spaced underwater installations, a pipeline section is towed from the first to the second installation, the front and rear ends being maintained above the sea bed by a system of floats and trail-ropes and the intermediate portion of the pipeline section being ballasted so as to be supported on the sea bed, whereafter the two end portions of the pipeline are inserted into the respective installations, and the floats eventually ballasted or liberated.

Abstract: An installation for the release of floats supporting by individual cables a structure submerged in an aqueous medium, comprising attachment means fixed on the structure and co-operating with one end of said cable, the other end carrying the float, liberating means co-operating with said attachment means, and a control station for said liberating means, wherein the first of said liberating means is connected to a principal control line connected to the control station, the subsequent liberating means being connected together in such manner that they are automatically and successively actuated after said first liberating means has been actuated via the principal control line, the principal control line and the connections between successive liberating means consisting of fluid pressure lines or electric cables.

Abstract: A method and apparatus for fabricating an offshore structure intended to be installed at sea comprising a support structure and a platform mounted on the structure. The platform is made up of one or more pieces that are floatable in water. The support structure is immersed to a depth sufficient for the portion thereof intended for the reception of the platform to be situated near the level of the latter. The platform is then fixed to the support structure which is then made lighter and brought to the place where it has to be installed.