A method of installing foundation elements, in particular (mono)piles having a diameter of five meters or more, in an underwater ground formation includes lowering a leader from a surface vessel with at least the tip of the leader into the water, and lowering a foundation element and/or a noise mitigation screen along the leader.

A method of installing foundation elements, in particular (mono)piles having a diameter of five meters or more, in an underwater ground formation includes lowering a leader from a surface vessel with at least the tip of the leader into the water, and lowering a foundation element and/or a noise mitigation screen along the leader.

A method and a device to create a foundation in which a foundation pipe is driven into the soil. At least one bore is created into the soil in the perimeter area of the foundation pipe to insert before ramming by means of a drilling tool the diameter of which is significantly smaller than a diameter of the foundation pile. The soil material removed during drilling remains essentially within the bore. Furthermore, a foundation with a foundation pipe which is created accordingly.

A passive annular grout seal assembly is disclosed for sealing an annular opening between a driven pile and a skirt pile sleeve for an offshore platform. The annular seals are located at the bottom of the pile sleeves near sea floor and automatically activated when piles are inserted and driven through the pile sleeves without any active operational procedure during offshore piling. The seal configuration fully utilizes the seal height, the grout column height and the density difference between grout and sea water to produce enhanced sealing capacity against the column of grout above.

A support structure for an offshore device is provided, including a vertical guide sleeve and three elongated guide sleeves positioned around the vertical guide sleeve, and various braces connecting the elongated sleeves and the vertical guide sleeve. The support structure also includes a transition joint including a cylindrical portion for connection to an offshore device, such as a support tower of a wind turbine assembly, and a conical portion connected to the vertical guide sleeve. To provide resistance to thrust, bending, and torsional fatigue, at least one set of braces is formed in an oval, racetrack, obround, or stadium configuration, and one or more horizontal stiffeners are positioned in the transition joint to maximize the strength of the support structure.

A support structure for an offshore device is provided, including a vertical guide sleeve and three elongated guide sleeves positioned around the vertical guide sleeve, and various braces connecting the elongated sleeves and the vertical guide sleeve. The support structure also includes a transition joint including a cylindrical portion for connection to an offshore device, such as a support tower of a wind turbine assembly, and a conical portion connected to the vertical guide sleeve. To provide resistance to thrust, bending, and torsional fatigue, at least one set of braces is formed in an oval, racetrack, obround, or stadium configuration, and one or more horizontal stiffeners are positioned in the transition joint to maximize the strength of the support structure.

Disclosed embodiments relate to systems and methods for mating a wind turbine off-shore to a spar buoy without the use of a crane barge. The system may include a spar buoy, wherein the spar buoy is secured to a foundation, and a wind turbine to be installed on the spar buoy. The system may also include a first truss affixed to the top of the spar buoy and a second truss affixed to the bottom of the wind turbine. The first truss may comprise either stabbings or receptacles configured for mating to the second truss and the second truss may comprise either receptacles or stabbings configured for mating to the first truss.

Disclosed embodiments relate to systems and methods for mating a wind turbine off-shore to a spar buoy without the use of a crane barge. The system may include a spar buoy, wherein the spar buoy is secured to a foundation, and a wind turbine to be installed on the spar buoy. The system may also include a first truss affixed to the top of the spar buoy and a second truss affixed to the bottom of the wind turbine. The first truss may comprise either stabbings or receptacles configured for mating to the second truss and the second truss may comprise either receptacles or stabbings configured for mating to the first truss.

The present invention is a grouting method for single pile rock-socketed foundation for offshore wind power, comprising: driving a steel casing into an overburden layer to dig the overburden layer and a rock stratum so as to dig a pile hole; hoisting a steel pipe pile into the steel casing and positioning the steel pipe pile in the pile hole, wherein an annular cavity is formed between the inner walls of the steel pipe pile and the pile hole and the bottom of the steel casing; grouting a first grouting layer to the bottom of a pipe hole of the steel pipe pile; grouting a plurality of grouting layers into the upper end of the first grouting layer in the annular cavity; and pulling out the steel casing, wherein after a grouting solution is aged, the steel pipe pile is stably connected to the overburden layer and the rock stratum.

The invention relates to a suction pile comprising a cylinder shaped body (1) with a closed end (3) and an open end (2), means (4) for attaching an arrangement to ejecting entrapped water, air and mud, but also provide a pressure difference within the suction pile during installation, and an attachment system (10) for attaching external equipment to the suction pile, the suction pile is formed with a skin portion (17) and at least one flange portion (6). At least one of the flange portions (6) comprises an element (11, 26) that form at least a part of the attachment system (10) for external equipment.