A rotor hub for a wind turbine may generally include a hub body defining both a plurality of blade flanges and a plurality of access ports spaced apart from the blade flanges. In addition, the rotor hub may include a ladder assembly extending within an interior of the hub body. The ladder assembly may include a plurality of platforms, with each platform defining a planar surface and being circumferentially aligned with a respective one of the plurality of access ports. The ladder assembly may also include a connecting frame extending between each pair of adjacent platforms so as to couple the adjacent platforms to one another. The connecting frame may extend lengthwise along a reference line defined between the adjacent platforms. The platforms may be positioned relative to one another such that the reference line extends at a non-perpendicular angle relative to the planar surfaces defined by the adjacent platforms.

A post-tensioned concrete cap foundation has helical anchors with pipes having several helical discs welded around the pipe perimeter to spin drill deep into subsurface soils or other soft materials with holes in the pipe for high pressure-grouting in place. The helical anchor pipes include a tensioning element for pulling and post-tensioning the helical anchor. The helical anchors are tension anchors which can be converted to compression anchors. The helical anchors in tension serve to pull the foundation cap down to compress the underlying soil while the compression anchors limit the maximum settlement of the concrete foundation cap. The foundation also includes perimeter-forming and interior corrugated metal pipes with upper and lower sleeved horizontally extending radial bolts that are secured to the pipes and post-tensioned to provide lateral foundation compression.

A foundation system for the foundation of an offshore structure includes a monopile having an anchoring portion anchorable in a seabed and a connection portion disposed at the opposite end. A platform structure is connected directly to the connection portion of the monopile or indirectly via a transition piece. The platform structure is disposable above a water surface. The foundation system includes at least two stabilizing devices connected directly to the platform structure or indirectly to the platform structure via the transition piece. The stabilizing devices are attachable to the seabed such that tensile forces or compression forces are transmittable between the seabed and the platform structure. Securing points on the stabilizing devices, together with the connection portion of the monopile, define a plane having a horizontally extending component.

A retrofit reinforcing structure addition and method for an existing gravity spread foundation for a wind turbine or the like haying a central pedestal and a spread section is provided. The retrofit structure addition includes a collar formed around the pedestal of the spread foundation. The collar is formed by a shape sustaining member, such as a CMP, placed around the pedestal to define an annular ring between the CMP and the pedestal that is filled with cementitious material. Radial bolts extend horizontally through the collar and into the side of the pedestal. Soil and/or rock anchor bolts extend vertically through the collar, the spread portion of the foundation and into the underlying soil and/or rock substrate. The radial and anchor bolts are post-tensioned to ensure that the cementitious material of the collar remains in compression and the bolts are always in static tension, strengthening the original gravity spread foundation and extending the fatigue life thereof.

The present invention discloses a portable and re-useable grillage (100) for receiving and supporting a heavy load during transportation as well as methods of making and using same. The grillage (100) comprising a base (3); a load bearing structure (4) coupled to the base (3), the load bearing structure (4) is used for supporting the heavy load; and a framework (5) attached to the load bearing structure (4). The grillage (100) is containerized such that the combination of the base (3), load bearing structure (4) and the framework (5) forming the grillage has external dimensions and weight that conforms with ISO specifications for an intermodal container. The containerized grillage (100) may be used with different sized legs for different sized heavy loads. It may also be shipped in a vertical stacked formation using cost-effective standard shipping for containers.

Foundation systems and methods using in-situ shaped pile-anchors that are particularly adapted for use in aquatic environments. The shaped pile-anchor of the invented foundation includes a concrete filled tubular metal casing, the bottom end of which is positioned at a predetermined depth in the ground (e.g., aquatic-floor soil) and the top end of which protrudes above the water or soil surface. Concrete fills the inside the metal casing, substantially all the way to the top end of the casing, forming an upper portion of a concrete column. The lower portion of the concrete column extends down below the bottom end of the metal casing and further into the ground. The lower portion is shaped to have a cross-section greater than the cross-section of the upper portion, which equals to the inner diameter of the tubular metal casing. A platform is coupled to one of more of the shaped pile-anchors to support a structure 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.

The invention introduces a connection system for connecting a shaft of a wind tower to a support surface, by means of a shaft, a foundation cage and a plurality of pairs of tendons wherein each tendon has a lower anchoring adapted for the placement thereof inside the foundation, an upper anchoring, at least one strand with a first end and a second end, the strand extending from the upper anchoring to the lower anchoring, a pair of sleeves for each strand, a sleeve fixed to the upper anchoring and a sleeve fixed to the lower anchoring, each sleeve housing a segment of the strand. Additionally, the system introduces a method for connecting a shaft of a wind tower to a support surface.

A method of forming a wind turbine foundation includes providing an anchor cage in an excavation pit, the anchor cage including an upper flange, a lower flange, and a plurality of anchor bolts extending therebetween. A first cementitious material is directed into the excavation pit so that the anchor cage becomes at least partially embedded in the material, which is allowed to cure to form a rigid body. A connecting element is selectively engaged with the upper flange and an actuating element is positioned in operative relation with the connecting element, the connecting and actuating elements positioned in non-contact relation with the anchor bolts. The actuating element is actuated relative to the connecting element to raise the upper flange from the rigid body into a leveled position. A second cementitious material is directed into a space beneath the raised upper flange and is allowed to cure to form a support layer.

The invention relates to a foundation for a wind turbine, wherein the foundation comprises substantially prefabricated elements, preferably made of reinforced concrete, with a first, vertically extending base-like portion, on which a tower of the wind turbine can be arranged, and a second substantially horizontally extending portion as foundation body, which is in contact with the ground. The first portion is arranged above the second portion and has at least one closed, preferably sleeve-shaped, base element, which is annular or polygonal, and the second portion is formed from at least two horizontal elements, which each have at least one base portion. The at least one base element of the first portion and the base portion of the horizontal element of the second portion have substantially vertical apertures, which are mounted in line with one another and in which substantially vertical bracing elements, preferably threaded rods, are arranged. The at least one base element of the first portion and the at least two horizontal elements of the second portion are preloaded against one another by the substantially vertical preloading elements. No further fastening means, in particular horizontal fastening means, are necessary for dissipation of the loads from the wind turbine.