A reinforced tensionless concrete pier foundation for supporting a tower and a method of constructing the same is provided, the foundation having an outer CMP and an inner CMP with an annular space therebetween in which a plurality of sleeved tower anchor bolts are embedded, and the pier foundation including at least one reinforcement structure that at least partly encircles the outer CMP to provide one or more of increased lateral stiffness, increased shear resistance and overturning (upset) moment capacity, reduced bending, displacement, and deflection of the top of the pier, and improved conditioning, containment, skin friction and lateral bearing capacity of the surrounding soil and/or rock substrate that supports the tensionless pier.

A post-tensioning system that is configured for use with concrete wind turbine foundation designs to post-tension the foundations and reduce the amount of reinforcement steel that is needed compared to conventional non-post-tensioned, steel reinforced concrete foundation designs. In the case of an inverted T gravity foundation, the post-tensioning system described herein reduces the amount of reinforcement steel that is required by 30-40 tons.

Offshore structure comprising a pile of a foundation and at least one offshore element, mounted on the pile, forming a slip joint, wherein between an inner surface of the offshore element and an outer surface of the pile: —a coating, especially an anti-fouling coating is provided, increasing friction between the said two surfaces and/or preventing corrosion of one or both of said surfaces and/or —at least two spaced apart areas are provided with a substance, forming a seal between the said outer surface and the said inner surface, near an upper end of the pile and the off shore element and between a lower end of the off shore element and the pile.

A method for pretensioning a tower of a wind power installation, comprising the steps: providing a tensioning device having an adapter element and/or a foundation arrangement and a tensioning element, and/or an adapter element and/or a foundation arrangement, fastening a lower end of a tensioning element a fastening means of the adapter element, fastening an upper end of a tensioning element to an upper end of the tower, tensioning the tensioning element at the lower end of the tensioning element and/or at the upper end of the tensioning element, wherein the tensioning of the tensioning element is effected by reduction of a clearance between the foundation and the adapter element.

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.

Offshore structure comprising a pile of a foundation and at least one offshore element, mounted on the pile, forming a slip joint, wherein between an inner surface of the offshore element and an outer surface of the pile: a coating, especially an anti-fouling coating is provided, increasing friction between the said two surfaces and/or preventing corrosion of one or both of said surfaces and/or at least two spaced apart areas are provided with a substance, forming a seal between the said outer surface and the said inner surface, near an upper end of the pile and the off shore element and between a lower end of the off shore element and the pile.

A system for holding a tubular sleeve (2) in a receiving structure during setting of a cement or other binder introduced in a fluid state between the sleeve (2) and the receiving structure, comprising:—at least one expandable structure (4) mounted on the sleeve (2), deformable from an inactive configuration allowing insertion of the sleeve (2) in the receiving structure to an active configuration immobilizing the sleeve (2) in the receiving structure,—at least one corresponding tool to be inserted in the sleeve (2), configured for acting on the expandable structure (4) to cause it to pass from the inactive configuration to the active configuration.

A hybrid offshore wind turbine includes a monopile, friction wheel, and suction bucket.

In a general aspect, suction anchors are presented for securing structures to an underwater floor. The suction anchors include a tubular body formed at least in part of cementitious materials and having a closed end and an open end. The tubular body includes an edge defining an opening for the open end. The edge is configured to penetrate the underwater floor. The suction anchors also include a port configured to fluidly-couple a cavity within the tubular body to an exterior of the tubular body. The suction anchors additionally include a pad eye extending from an outer surface of the tubular body and configured to couple to a mooring line. In another aspect, methods of manufacturing the suction anchors are also presented.

A foundation for a structure pre-stressed via a plurality of tensioning members includes a foundation slab and a suspension device cast into the foundation slab. The suspension device includes an anchor element, which may be an upper anchor plate, located at least as high as an upper side of the foundation slab, the anchor element for attachment to one of the tensioning members. The suspension device also includes a lower anchor plate located at least as low as within a lower third of the foundation slab. The structure may be a container, a tower or a wind turbine tower. The structure may include a stack of prefabricated concrete parts. The disclosure is also directed to the combined structure and foundation, and to a method of manufacturing a structure having a foundation.