The present invention relates to an assembly for installing a pile (2) in a seabed (3), the assembly comprising a vessel (23) comprising a positioning system for keeping the vessel (23) at an installation location relative to the seabed, the positioning tem (5) having a positioning stiffness (7); a pile guiding system configured to guide the pile (2) during installation thereof, the pile guiding system comprising a base (9) provided on the vessel; a first guiding device connected to the base, the first guiding device being configured to accommodate the pile during installation thereof; a resilient member (11) for providing a resilient connection between the vessel (23) and the pile during installation thereof for allowing relative motions between the pile (2) and the vessel (23), the resilient member having a connection stiffness, wherein the resilient member (11) is configured and intended to keep a natural period of a pivoting movement of the pile about the seabed caused by waves during installation thereof longer than a dominant wave period of a wave spectrum at the installation location by providing the resilient connection with a low connection stiffness.

A monopile foundation guiding device is provided. The monopile foundation guiding device includes at least one guiding unit; each of the at least one guiding unit includes a single driving unit, a transmission unit, and a clamping unit; the clamping unit includes at least two clamping arms, and a clamping space for clamping a monopile foundation is formed between the at least two clamping arms; the single driving unit transmits power to the transmission unit, and the at least two clamping arms are driven to operate synchronously by means of the transmission unit, so that the clamping unit is opened or closed.

An anchor device for anchoring a floating structure to the seabed with an anchor chain having a shackle at one end of the chain. The anchor device includes a mooring bolt for being inserted into a borehole drilled in the seabed and a support plate having a lower face for resting on the seabed and an upper face with a through hole through which the mooring bolt passes through the support plate for being inserted into the borehole. The upper face of the support plate has a connection point for coupling the shackle of the end of the chain, such that when the floating structure is anchored to the seabed, the chain is subjected to tensile stresses causing a force to be applied at the connection point and not directly to the mooring bolt.

Provided is a support structure and a method for manufacture thereof. The support structure, in one aspect, includes first and second expanded metal structural pillars positioned within the ground by a distance (d.sub.1), the first and second expanded metal structural pillars comprising a metal that has expanded in response to hydrolysis. In at least one other aspect, the support structure includes one or more beams spanning the first and second expanded metal structural pillars.

A hybrid anchor (10) comprises a caisson comprising a lid (35) and a rigid skirt (37) wherein the skirt defines an open end of the caisson and the lid comprises a valve, the skirt of the caisson being configured to engage with a substrate upon which it is placed, thus defining a sealed interior space and, in use, the skirt (37) is induced to sink into the substrate by evacuating the contents of the interior space through the valve. A drilling template is fixed to the lid (35) of the caisson, the drilling template being configured to receive at least one pile (40) at a respective location relative to the caisson lid (35) such that the at least one pile (40) may be driven though the caisson lid and into the substrate at an angle from 90 degrees to the plane of the lid up to an angle avoiding intersection between the at least one pile and the skirt to fix the position of the hybrid anchor within the substrate.

A multi-impeller passive-rotating-stirring-type rotary drilling rig for open caissons includes a hollow main drill pipe, a drill bit, four cutting edges, four impeller shafts, four passive impellers and a rotation bracket. Through being uniformly distributed at a peripheral of the drilling rig, four passive impellers contact with a hole wall of a borehole during the drilling process for passively generating relative rotation opposite to the rotation direction of the drill bit, so as to accelerate sufficient mixing of silt and water for forming mud during the drilling process.

Proposed is a construction method for an underwater concrete block structure. The concrete block structure is formed by stacking a plurality of concrete blocks on a foundation concrete block structure by using a guide pipe, and a concrete column is formed by, before removing the guide pipe, inserting a concrete column forming set such as a waterproof membrane through the inside of the guide pipe, so that the waterproof membrane can be inserted conveniently and safely and the construction speed of the concrete block structure can be further improved.

Provided is a support structure and a method for manufacture thereof. The support structure, in one aspect, includes first and second expanded metal structural pillars positioned within the ground by a distance (d.sub.1), the first and second expanded metal structural pillars comprising a metal that has expanded in response to hydrolysis. In at least one other aspect, the support structure includes one or more beams spanning the first and second expanded metal structural pillars.

A method of installing an upright elongate hollow subsea foundation that is higher than it is wide, such as a suction pile. The foundation is at least partially embedded in seabed soil. A partition layer is placed within the foundation, for example by injecting a grout, supported by a plug of soil that is surrounded by the foundation. The partition layer is placed on the plug of soil at a level that is spaced from the top of the foundation by at least 20% of the height of the foundation. Above the partition layer, the interior of the foundation may be filled with water and/or a rigid body, such as a solid mass or a hollow liquid-filled tank.

A pile upending and holding system includes a support assembly configured to be mounted on the vessel and to provide compensation for wave-induced motion of the vessel to maintain a predetermined X-Y location of the pile holder independent of said motion, and a pile holder mounted on the support assembly to be tillable about a substantially horizontal tilt axis. The pile holder includes a lower ring and an upper ring, and a pile holder frame supporting the lower ring and upper ring, the upper ring longitudinally spaced from the lower ring. Each of the rings include pile engaging devices distributed about the circumference thereof, each pile engaging device being adapted to engage an exterior of the pile extending through the lower and upper ring. Each of the lower ring and upper ring includes a ring base fixed to the pile holder frame and one or more movable jaws, movable between a closed position for holding and guiding the pile and an opened position for entry of the pile. The pile holder is provided, below the lower ring thereof, with a pile foot end support for engaging a longitudinal end of the pile to limit longitudinal movement thereof.