An apparatus for driving a pile section having a central opening into the ground includes a mast attachment with roped hydraulic cylinders, a high frequency hydraulic impact hammer connected with the mast, and a drive cap. The mast with roped hydraulic cylinders provides for vertical movement of the high frequency hydraulic impact hammer, and the drive cap connects with the high frequency hydraulic impact hammer and a pile section to transfer the drive force of the hammer to the pile section. When the mast is connected with an excavator and the drive cap is connected with the high frequency hydraulic impact hammer, a pile section is connected with the drive cap lower end and the high frequency hydraulic impact hammer is operated to drive the pile section into the ground. A system for driving piles into the ground includes an excavator, an apparatus connected with the excavator, and a plurality of base pile sections. The pile sections have an upper end surface containing a central opening which connects with the apparatus prior to driving the pile sections into the ground. The apparatus includes a mast with roped hydraulic cylinders, a high frequency hydraulic impact hammer connected with the mast, and a drive cap. The mast with roped hydraulic cylinders provides for vertical movement of the high frequency hydraulic impact hammer, and the drive cap connects with the high frequency hydraulic impact hammer and a pile section to transfer the drive force of the hammer to the pile section.

Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.

Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.

Systems and methods for reducing scouring around piles are described. The system includes a pile and an enclosure. The pile has a maximum cross-sectional dimension, D.sub.p. The enclosure is circumferentially disposed around the pile, the enclosure having a first end proximate a surface of a seabed; a second end distal the surface of the seabed; and a maximum cross-sectional dimension, D.sub.e, wherein D.sub.e is at least 1.25*D.sub.p.

The invention in one aspect provides an apparatus and method for forming a connection between an inner tubular and a caisson of an offshore structure. The apparatus comprises a mandrel, and a seal arrangement disposed on the mandrel and configured to create a seal between the mandrel and an inner surface of an inner tubular in which the apparatus is located. The seal arrangement comprises first and second cup seals, axially separated on the mandrel, and configured to define a substantially annular volume between the mandrel and the inner tubular in use. A pressure transmission path delivers a pressurised fluid to the annular volume, and the apparatus is configured to pressurise the annular volume and thereby expand the inner tubular in a radial direction and into contact with the caisson to form a connection between the inner tubular and the caisson.

The invention in one aspect provides an apparatus and method for forming a connection between an inner tubular and a caisson of an offshore structure. The apparatus comprises a mandrel, and a seal arrangement disposed on the mandrel and configured to create a seal between the mandrel and an inner surface of an inner tubular in which the apparatus is located. The seal arrangement comprises first and second cup seals, axially separated on the mandrel, and configured to define a substantially annular volume between the mandrel and the inner tubular in use. A pressure transmission path delivers a pressurised fluid to the annular volume, and the apparatus is configured to pressurise the annular volume and thereby expand the inner tubular in a radial direction and into contact with the caisson to form a connection between the inner tubular and the caisson.

A suction anchor and method of installing the suction anchor. The suction anchor including a suction chamber bounded by: a circumferential outer wall; an upper wall; and an internal housing wall. The internal housing defining a passage for receiving wellhead components that may be secured to the suction anchor. The suction chamber has a minor upper portion and a major lower portion. The minor upper portion having internal reinforcing members extending along the inside of the upper wall from the outer walls to the internal housing. The major portion is adapted to be embedded in a seabed and the minor portion is adapted to project from the seabed when the anchor is installed. The reinforcing members serve to reinforce the upper wall of the chamber against collapse and to rigidly support the internal housing to resist forces arising from bending moments applied to wellhead components received and secured therein.

The disclosure provides novel means and methods for the repair of water caissons in situ, for example at sea. The method generally includes providing a woven composite sock inside the caisson. The method further includes inserting a calibration tube into the composite sock within the caisson. The calibration tube can be filled with a pressurised fluid, preferably water, to pressurise the sock against the internal walls of the caisson. The sock can be infused with an epoxy resin. The resin is preferably water-curable. The composite sock can be allowed to cure with the calibration tube in place. The calibration tube can apply pressure to press the composite sock against the inner wall of the caisson. Once the composite matrix has cured to form a cured composite liner for the caisson, the calibration tube can be removed.

Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.

Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.