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.

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.

The invention relates to a method for ground-working at a bottom of a body of water and a cleaning device for cleaning an underwater ground-working apparatus. The cleaning device has an enclosing body which extends substantially from a bottom of a body of water to above the water surface and enclosing an inner space, along which the ground-working apparatus can be moved, and a separating device, through which in the enclosing body an upper portion of the inner space can be separated off to form a cleaning area, in which the ground-working apparatus can be received and soil and contamination cleaned from it.

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.

The invention relates to a method for ground-working at a bottom of a body of water and a cleaning device for cleaning an underwater ground-working apparatus. The cleaning device has an enclosing body which extends substantially from a bottom of a body of water to above the water surface and enclosing an inner space, along which the ground-working apparatus can be moved, and a separating device, through which in the enclosing body an upper portion of the inner space can be separated off to form a cleaning area, in which the ground-working apparatus can be received and soil and contamination cleaned from it.

An anchor installation vehicle that includes a vehicle frame having a top end and bottom end, one or more rotational thrusters, and an anchor system configured to hold an anchor extending from the bottom end of the vehicle frame.

The present invention provides a method for installing an off-shore anchoring system comprising drilling a borehole in a seabed, the borehole comprising a first lower portion in communication with a second upper portion. The cross-sectional dimensions of the first lower portion are smaller than the cross-sectional dimensions of the second upper portion. An inwardly protruding abutment surface is provided at a transition point located therebetween. The method further comprises introducing settable locking media into the borehole. The method further comprises subsequently introducing an off-shore anchoring system comprising an anchor pile and a lateral load transition member into the settable locking media within the borehole, such that the anchor pile is located within the first lower portion of the borehole, and the lateral load transition member is located within the second upper portion of the borehole and spaced apart from the anchor pile.