Abstract: A circular pipe member is penetrated into the seabed by a suction pressure, and a plurality of circular pipe members are vertically stacked thereon and integrated thereto to construct a cofferdam. When dismantling the cofferdam, the circular pipe members are disassembled and dismantled in order by using a lifting wire installed at a newly constructed structure installed in the inner space of the cofferdam.

Abstract: Modular structure for protecting an offshore vessel in a body of water from forces of ice features comprising a protective harbor wall, a flotation support, a pile, and a telescoping connection. The telescoping connection is operatively coupled to the protective harbor wall and the flotation support and constructed and arranged to axially move the protective harbor wall between a retracted position and a raised position. The protective harbor wall is constructed and arranged to enclose a harbor space and to counteract the forces of ice features. The flotation support supports the protective harbor wall and is constructed and arranged to change net buoyancy of the modular protective structure to submerge the structure such that the flotation support is positioned on a seabed. The pile is constructed and arranged to be partially disposed in the seabed to maintain the position of the flotation support on the seabed.

Abstract: An enclosure having a bottom plate, a wall, and an opening to pass a portion of a pier into the enclosure. A first sealing member coupled to the bottom plate. Watertight tanks coupled to the enclosure float the enclosure in a body of water, at a position above a footing of the pier with the portion of the pier in the enclosure, sink the enclosure to compress the first sealing member between the bottom plate and a ledge of the footing, and re-float the enclosure. A method includes floating and navigating the enclosure to the position and adding weight to sink the enclosure. A plurality of adjustable length structures may be lengthened to exert a downward force on the bottom plate to secure it to the ledge. A second sealing member may be forced into the opening between the pier and wall of the enclosure to facilitate dewatering the enclosure.

Abstract: The invention relates to a maintenance platform (1, 10) for an oil rig equipped with a work platform and at least three frame legs (2) b, particularly a jackup oil rig, wherein at least one corner module (6) having at least one platform can be moved along at least one frame leg (2) of the oil rig, wherein the at least one corner module (6) is equipped with at least one climbing unit (110), which positively interacts with at least one gearing system (4) that is arranged on the frame leg (2) in order to bring about an up or down movement of the at least one corner module (6) along the frame leg (2).

Abstract: The present invention provides a method of creating a building structure to be installed on a basin floor wherein the base for erecting the structure would be an element of such a block and this block would be placed on the basin floor in such a way, and would be fixed in position relative to it in such a manner, that this base could be used as a foundation for stationary, large-sized heavy structures and also to ensure the possibility of using the block elements as members of the structure being erected and thus to increase the economic efficiency of the method.

Abstract: A needle-beam cofferdam, needles and associated method for dry isolation of a water passage of a dam, the method comprising providing a support beam which spans between piers of the water passage, providing at least one hollow metal needle having a major axis, and positioning the hollow needle with the major axis substantially vertically oriented, the hollow needle engaging with a sill of the dam and engaging with the support beam. A plurality of vertically positioned needles may thereby isolate the water passage. The method also includes positioning of hollow needles with the major axis in a substantially horizontal orientation.

Abstract: A method of making an island including the steps of: manufacturing a plurality of formations; transporting the formation to a site in a water body; assembling said formations proximate one another; said formations defining an artificial island structure with both below and above water line components. Methods are described, as well as methods and components for both island and existing island and land enhancements.

Abstract: A portable cofferdam and method for use in stabilizing the subsurface of box culvert structures. The portable cofferdam is inserted inside the tubular section of large box culverts, which are often used as road crossings over streams, creeks and small rivers. The portable cofferdam is designed as a chamber having an open top end and open bottom end with a floor seal to engage against the box culvert floor. Once inside the culvert, the chamber floor seal is compressed against the culvert floor by an expansion device which extends against the culvert ceiling. Once a proper seal is created against the culvert floor, the chamber is dewatered. With the culvert floor exposed, a hole can be drilled through the culvert floor bottom and grout or other hard curing material is pumped into the subsurface void for stabilization of the box culvert structure.

Abstract: A fence post includes a weighted base and a vertical member. The vertical member has a first end and a second end. The first end is secured to and extends substantially vertically from the weighted base. A float is provided that is axially movable along the vertical member from the first end toward the second end. A stop is spaced from the first end to limit travel of the float along the vertical member. This fence post is suited for use in wet areas, as it floats with the weighted base keeping the fence post in a stable upright condition.

Abstract: A portable cofferdam and method for use in stabilizing the subsurface of box culvert structures. The portable cofferdam is inserted inside the tubular section of large box culverts, which are often used as road crossings over streams, creeks and small rivers. The portable cofferdam is designed as a chamber having an open top end and open bottom end with a floor seal to engage against the box culvert floor. Once inside the culvert, the chamber floor seal is compressed against the culvert floor by means of an expansion device which extends against the culvert ceiling. Once a proper seal is created against the culvert floor, the chamber is dewatered. With the culvert floor exposed, a hole can be drilled through the culvert floor bottom and grout or other hard curing material is pumped into the subsurface void for stabilization of the box culvert structure.

Abstract: The invention relates to a device for sealing a caisson comprising a bottom, two upright side walls and a back wall, and intended for carrying out works to a sheet pile wall below the water line, characterized in that it comprises the combination of an inflatable continuous air chamber (8); a series of deformable sealing elements (9); a core (10) which can be displaced between each of said sealing elements (9) and the air chamber (8) and guiding plates (11) and means for allowing the lateral displacement of said sealing elements with respect to the caisson.

Abstract: A mobile cofferdam for use in the construction of elongated structures win a body of water is characterized by a water-tight rectangular shell which is guided and supported off the previously constructed segment of the sill or wall structure being built. The mobile cofferdam shell is floated into place, sunk, dewatered, and used as a cofferdam during construction of the sill. The mobile cofferdam is guided and supported off the previous placed concrete sill or wall and proceeds in a horizontal slip-form fashion. The walls of the mobile cofferdam are designed as spaced truss structures with skin plate on the inner, outer, top and bottom surface thereof to define a chamber which can be filled or evacuated with water to float the shell structure. The trailing end of the shell conforms to the sill or wall under construction and includes seals along the contact area for mating with the previously constructed sill portion.

Abstract: This invention concerns equipment designed for carrying out work under dry conditions on an underwater structure in particular on a sheet pile planking wall with grooves at more or less regular intervals comprising a caisson brought through two vertical walls and a floor in contact with a sheet pile planking wall and means to keep the caisson pressed against the sheet pile planking wall comprising the floor of the caisson being fitted with horizontally adjustable sealing sheets that slide in the grooves of the sheet pile planking wall.

Abstract: A method and assembly for temporarily isolating an area within a waterway preparatory to dredging in order to prevent disturbed sediment from spreading throughout said waterway. A plurality of spaced support column assemblies are lowered from a barge outer hull into soil forming a periphery of the area to be dredged. A separate side panel member is then lowered between each pair of support columns and water is then removed from an area completely encircled by the side panel members and support column assemblies before the area is dredged. After dredging operations are completed within the area, water is then reintroduced into the area and the side panels and support columns are withdrawn.