A method includes mounting a lower platform block (300) to a plurality of piles (215) positioned on a surface. The lower platform block includes a first frame (315), a plurality of docking assemblies (305) connected to the first frame and engaging the piles, and a plurality of conductor tubes (310) connected to the first frame to a plurality of piles. The docking assemblies are released from the piles to separate the lower platform block from the piles.

A variable-draft barge configured to transfer loads in a body of water, and having a water line which is a function of the draft; the barge having: a hull; an underbody; at least one first chamber located in the hull and floodable selectively to alter the draft of the barge; at least one flood valve located below the water line to flood the first chamber; and a control device configured to selectively open the flood valve to flood the first chamber.

Provided is an offshore wind turbine installation arrangement, including a lifting assembly realized to hoist a suspended load between a floating installation vessel and a wind turbine assembly, the lifting assembly including a crane supported by the floating installation vessel; a sensor arrangement realized to sense at least a motion of the floating installation vessel; and a controller realized to control elements of the lifting assembly on the basis of the sensed installation vessel motion to adjust the position of the suspended load relative to the wind turbine assembly. Also provided is a method of hoisting a load between a floating installation vessel and an offshore wind turbine assembly.

A method for connecting an offshore structure (2) to a subsea pile (1) includes inserting a connecting portion (14) of the structure inside the subsea pile. The connecting portion (14) comprises a plurality of outwardly moveable clamping members (5). Moving each of the plurality of clamping members (5) into gripping contact with an inside surface of the subsea pile provides a mechanical connection. The method may also include a grouting step to make the connection permanent.

A method includes mounting a first jacket connector block (400) to an apparatus. The first jacket connector block includes a first frame (415), a plurality of first conductor tubes (405) connected to the first frame, a first plurality of releasable connectors (420) coupled to first ends of the first conductor tubes, and a second plurality of releasable connectors (420) coupled to second ends of the first conductor tubes and engaging the apparatus.

A marine or land habitation system includes a habitable chamber and a monopole column supporting the habitable chamber at a first end of the monopole column. The monopole column includes a second end, opposite the first end, for mounting in the seabed or dry land. The habitable chamber is moveable with respect to the column both rotationally and vertically.

An off-shore wind turbine system is assembled using a platform or jack-up vessel, and a first base anchored to the seafloor at a bade assembly off-shore location. A buoyant tower is attached to the first base. A crane provided on the platform or jack-up vessel is used to lift blades and blades, which are then coupled to a turbine held in a nacelle provided at the top of the buoyant tower. The buoyant tower, the nacelle, and the blades are detached from the first base. The buoyant tower, the nacelle, and the blades are towed to a wind farm and connected to a second base provided in the wind farm. The buoyant tower, the nacelle, and the blades are further stabilized using mooring lines spanning between the buoyant towers and other bases provided in the wind farm. The first base and/or the second base include anti-rotation features.

A device and a method for securing a connection to be formed between a leg of a marine structure and a pile of a fundament fastened in a seabed. The connection has the leg partly inserted into an opening of the pile. The device is configured to be firmly connected to the leg. The device comprises a sleeve element configured, together with the leg of the marine structure, to be brought to vicinity of an upper portion of the pile. The device further has a clamping arrangement attached to the sleeve element comprising at least one clamping device configured to form an attachment between the sleeve element and the upper portion of the pile.

An apparatus and methods for installation of an offshore platform for supporting equipment installations is provided. The apparatus includes a vertical compression assembly and a counteracting tensioning tendon system. The vertical compression assembly may comprise multiple compression members, a column truss, or other configurations. The methods of fabrication, load out, and installation provide for cost-effective port and installation vessel requirements.

A device is for securing a connection to be formed between a leg of a marine structure and a pile of a fundament fastened in a seabed. The connection has the leg partly inserted into an opening of the pile. The device is configured to be firmly connected to the leg. The device comprises a sleeve element configured, together with the leg of the marine structure, to be brought to vicinity of an upper portion of the pile. The device further has a clamping arrangement attached to the sleeve element comprising at least one clamping device configured to form an attachment between the sleeve element and the upper portion of the pile.