Various aspects include devices, systems, and methods for securing an anchoring element to a seafloor. The methods may use a subsea anchorage installation system that may include a subsea grout supply assembly. The subsea grout supply assembly may include a variable volume grout storage chamber, a paddle, and a subsea grout pump. The variable volume grout storage chamber may be configured to transport dry grout to a seafloor. The variable volume grout storage chamber may include a water injection port configured to receive water for mixing with the dry grout on the seafloor. The variable volume grout storage chamber may also be configured to expand from a collapsed configuration as water is injected.

In an assembly of an offshore support structure for a wind turbine, tubular members are interconnected in grouted connections where a first tubular member has fastened to it a shell-unit comprising a cavity into which an end-part of a second tubular member is inserted and fixed by grouting. The cavity is closed by a rigid entrance-flange that is fastened to the walls of the shell-unit. The design converts forces acting on the second tubular member to compression forces acting on the grout in the cavity.

A method for anchoring a foundation structure (3) in a seabed (1) that includes introducing a receiving structure (6) into the seabed, lowering a support post (5) of the foundation structure (3) into the receiving structure (6), producing a connection between the receiving structure (6) and foundation structure (3) by filling the receiving structure (6) with a curable filling compound (7), and curing the curable filling compound (7), wherein the support post (5) is fixed in the receiving structure (6) prior to filling the receiving structure (6) with the curable filling compound (7). Also disclosed is a foundation structure (3) for an offshore wind turbine, for anchoring in a seabed (1), which includes at least one support post (5) to be introduced into a receiving structure (6), which has fixing elements (11, 20) for temporarily fixing in the receiving structure (6) before grouting is carried out.

An offshore platform for a marine environment includes a regulating tower section supporting at least one offshore wind turbine, at least one buoyancy tube connected between the regulating tower section, the at least one buoyancy tube having a tapered lower end extending to a seabed, and a concrete bed within the seabed. The tapered lower end is a cone-shaped bottom slab having a flat top surface with an apex of the cone-shaped bottom slab pointing downward towards the seabed. The concrete bed includes a reversed cone-shaped indentation to which the cone-shaped bottom slab is to be fixed within that was formed in the concrete bed by the cone-shaped bottom slab prior to the concrete bed hardening to a final design strength.

Various aspects include devices, systems, and methods for securing an anchoring element to a seafloor. The methods may use a subsea anchorage installation system that may include a subsea grout supply assembly. The subsea grout supply assembly may include a variable volume grout storage chamber, a paddle, and a subsea grout pump. The variable volume grout storage chamber may be configured to transport dry grout to a seafloor. The variable volume grout storage chamber may include a water injection port configured to receive water for mixing with the dry grout on the seafloor. The variable volume grout storage chamber may also be configured to expand from a collapsed configuration as water is injected.

The present disclosure provides an underwater packer, including an outer pile, a sleeve arranged inside the outer pile, a plug arranged at a bottom end of the sleeve, a grouting pipeline arranged on the sleeve, several resin flaps arranged between the outer pile and the sleeve, and a sealing cloth connected between two adjacent resin flaps through thermal fusion, a bottom end of the resin flap is hinged on the plug, and a top end of the resin flap abuts an inner wall of the outer pile. The outer wall of the outer pile and the inner wall of the sleeve are in direct contact with the grouting material, allowing the connection between the outer pile and the sleeve to be more secured. The inclined surface formed in the top portion of the resin flap and the pressing surface of the protrusion abut the inner wall of the outer pile.

In the assembly of the support structure of a wind turbine, N sets of a first tubular brace and a second tubular brace extend from a tower support. For each set, the second braces are connected at one or both of their end parts by a casted connection. The first brace or the tower structure has a casting cavity for accommodating an end of the corresponding second brace. In order to assemble the construction, the second brace is inserted into the cavity, after which the end of the first brace is lifted until the end of the second brace is inserted deeply enough into the respective cavity.