摘要:
A device for protecting against the scouring of granular fillings submerged in gravity structures in which a filling with granular materials must be deposited once the structures are submerged, so that the structures reach a weight sufficient to en sure the stability thereof against the actions to which they are subjected. The device consists of one or more porous covers that sit and/or are secured as an upper closure of the structure to protect the inner filling, each of the covers having a plurality of openings that are distributed on the surface thereof and have a size suitable to allow the passage of the filling material, which filling material is transferred to the inside of the structure simply by pouring until a height close to the cover is reached, leaving a margin or chamber between the two that is suitable for generating an internal turbulence that dissipates wave energy and incident currents, thereby making it difficult for the filling material to escape from the inside through the openings.
摘要:
A caisson for maritime works, consisting of a base (1) and at least one lateral wall (2) attached to the same and formed by a plurality of voussoirs (3). Within the same a main space (4) is defined, intended to receive granular material as ballast. The voussoirs (3) feature an upper side (5), a lower side (6) and lateral sides (7) and are arranged with the lateral sides (7) of adjacent voussoirs (3) attached to each other, forming horizontal segments (8). Said horizontal segments (8) are attached to other identical horizontal segments (8) to define the lateral wall (2) by means of the union of the lower sides (6) and upper sides (5) of the voussoirs (3) forming the same. The base (1) has a geometric shape which coincides with the geometric shape of the horizontal segments (8). A procedure for the assembly of said caisson for maritime works is also described.
摘要:
A foundation structure for locating an object mounted on the foundation structure on a sea bed or a river bed comprises an integral buoyancy device having variable buoyancy and a rigid control surface. The integral buoyancy device is movable relative to the foundation structure to vary the position of the rigid control surface and to control the position of the center of buoyancy relative to the position of the center of gravity. This stabilizes the foundation structure during submergence and surfacing. A method for controlling the deployment and retrieval of the foundation structure is also described.
摘要:
A method and vessel for removing or installing an offshore jacket structure in a body of water, the vessel having a generally planar main buoyancy section having the outline of a delta with an extension at the apex and auxiliary buoyancy sections extending transversely of the main buoyancy section at the ends of the base of the delta. The bottom parts of the auxiliary buoyancy sections have a rounded outer surface and contain heavy fixed ballast. The vessel may be rotated as it is brought close to the jacket structure with the auxiliary sections straddling the jacket structure. The vessel is rotated towards the jacket structure while its rounded bottom portion rolls on the seabed. Once the jacket structure is connected securely to the vessel, the vessel is rotated back to the initial position de-ballasting the auxiliary sections before it is brought to the surface.
摘要:
A floating platform for recovery of oil and gas from offshore oil and gas fields includes a hull having a portion located substantially below the water surface, and including a portion thereof which extends above the water surface. The platform is anchored to the seabed by one or more tendons secured to the base of the hull and to the seabed. The payload capacity of the floating platform is increased without redesigning the structural design of the hull by attaching a column extension or mounting a detachable buoyancy module to the lower end of the hull for accommodating changing platform payload requirements.
摘要:
A system for offloading LNG (liquified natural gas) from a tanker (26) in shallow waters, for regasing, or heating the offloaded LNG to produce gaseous hydrocarbons, or gas, for pressurizing the gas, and for flowing the gas to an onshore station (56), includes a structure that is fixed to the sea floor and projects above the sea surface and aids in mooring the tanker. In one system, the structure that is fixed to the sea floor is a largely cylindrical tower (12) with a mooring yoke (20) rotatably mounted on its upper end. A floating structure (14) such as a barge that weathervanes, has a bow end pivotally connected to a distal end of the yoke, so the barge is held close to the tower but can drift around the tower with changing winds, waves and currents. The tanker is moored to the barge so the barge and tanker form a combination that weathervanes as a combination. Regas and pressurizing equipment (32, 34) for heating and pressuring the LNG, and any crew quarters (36), are all located on the barge, so a low cost tower can be used. In another system, the structure is a breakwater (180).
摘要:
A system for offloading LNG (liquified natural gas) from a tanker (26) in shallow waters, for regasing, or heating the offloaded LNG to produce gaseous hydrocarbons, or gas, for pressurizing the gas, and for flowing the gas to an onshore station (56), includes a structure that is fixed to the sea floor and projects above the sea surface and aids in mooring the tanker. In one system, the structure that is fixed to the sea floor is a largely cylindrical tower (12) with a mooring yoke (20) rotatably mounted on its upper end. A floating structure (14) such as a barge that weathervanes, has a bow end pivotally connected to a distal end of the yoke, so the barge is held close to the tower but can drift around the tower with changing winds, waves and currents. The tanker is moored to the tower so the barge and tanker form a combination that weathervanes as a combination. Regas and pressurizing equipment (32, 34) for heating and pressuring the LNG, and any crew quarters (36), are all located on the barge, so a low cost tower can be used. In another system, the structure is a breakwater (180).
摘要:
A maritime dock structure including a plurality of hollow modules each having a buoyancy force associated therewith. A plurality of anchors are coupled to the modules and embedded in an underwater bed. Each anchor opposes the buoyancy force of its associated module as well as lateral forces and load forces directed into the underwater bed.
摘要:
A modular caisson installation demountably installed at a preselected water site. The modular caisson installation includes a plurality of caissons having tops and bottoms and being individually demountably installed in a predetermined configuration at a preselected water site with the caisson bottoms removably seated on a bed at the preselected water site. The caissons being constructed of one or more floatable sections each being fluid trimmable and fluid ballastable and having means for trimming and ballasting the section with fluid to effect controlled lowering and positioning thereof during formation of the installation and controlled raising and removal thereof by floatation to enable demounting of the installation.
摘要:
A method and apparatus for installing marine silos to a desired depth into the seabed such that the interior of the silos is void of seabed material to a desired depth. A submergable silo positioning template operatively supports a silo and excavation modules during surface transportation to the intended site and is capable while floating and submerged of raising and lowering the silo relative to the template and maintaining vertical alignment of the silo. The submergable excavating module incorporates apparatus for loosening and removing sea bed material within the silo thus permitting the silo and excavating module to descend to a desired depth in the seabed. The template and the excavating module are separated from the silo after silo installation and are reused for other silo installations. During silo installation the influence of hydrostatically stimulated force may be employed to assist forcible insertion of the silo into the soil of the seabed.