Floating structures

Floating structures are provided. The floating structures are suitable for use as floating runways for aircraft, floating roadways, and supports for other facilities. The floating structures include a deck and one or more pontoons attached to the deck. The pontoons, with the deck attached, are caused to float in water contained in a basin, which in turn floats in a body of water. The basin provides damping or isolation of forces due to currents in the body of water, or prevailing winds, to reduce undesired or excessive motion of the deck. The deck supports are preferably capable of limited lateral movement relative to the pontoons, thereby permitting some movement of the pontoons independently and reducing stresses on the structure.

FIELD OF THE INVENTION

The present invention relates to floating structures. In particular, the present invention relates to floating structures useful for maintaining platforms supporting airplane runways, bridges, or other structures afloat in bodies of water.

BACKGROUND OF THE INVENTION

Constraints such as shortages of available land when there is a need to locate a structure, either temporarily or permanently, either adjacent to land, or in a large body of water, have led to the development of floating platforms and the like that can support a structure on a body of water. For example, floating runways such as that disclosed in U.S. Pat. No. 5,906,171 provide water-borne surfaces for aircraft to land and take off, similar to surfaces on aircraft carriers. Floating airports, such as that disclosed in U.S. Pat. No. 5,398,635, can further include means for controlling the position of a floating airport by compensating for disturbances to such position by prevailing winds and currents. Complex structures, such as those disclosed in U.S. Pat. No. 5,799,603, have also been developed to provide stability under ocean conditions. According to the disclosure of the '603 patent, energy due to striking waves is partly absorbed by a buoyant load-bearing assembly that includes universal joints and shock-absorbing hydraulic cylinders.

Similarly, floating bridges and roadways have been developed for use in, for example, locations where conventional bridge construction and/or maintenance would be undesirably costly or difficult, or where a relatively short bridge span is required. The ability to transport such floating bridges to a site has been facilitated by utilizing foldable hulls, as described in U.S. Pat. No. 4,561,376, or by providing an amphibious vehicle that can be equipped with hulls and can function as a bridge or portion thereof, as described in U.S. Pat. No. 4,621,385. Such structures, while portable, are apparently somewhat complex.

It will be appreciated that in any geographic area adjacent to bodies of water, where land is scarce or not available for development, floating platforms may be desirable. Development of additional permanent or temporary facilities for manufacturing, power generation, housing or other commercial use may be desirable, but not practical in view of land use policies or community opposition. In the international context, there may be a need for facilities, such as airfields and housing facilities, for military and/or relief efforts, which cannot be located on land because of political and security concerns.

A need remains for floating structures supporting floating platforms suitable for use as aircraft landing strips, airports, roadways, bridges and off-shore facilities. A need also remains for such floating structures that are not subject to some motion caused by waves or water currents as to fail to be functional for their intended purposes. The present invention is directed to these and other objectives.

SUMMARY OF THE INVENTION

One aspect of the invention is a floating structure comprising at least one deck; one or more flotation means attached to and supporting the deck; means for reducing the effects of currents in a body of water on the flotation means; and mooring means for restricting translational motion of the floating structure. In some embodiments, the means for reducing the effects of currents include ballast means for controlling flotation of the structure in a body of water; and mooring means for restricting translational motion of the floating structure.

A further aspect of the present invention is a floating structure that includes at least one deck having an upper surface and a lower surface; one or more pontoons having an interior chamber, attached to and supporting the deck; and a basin. The pontoon chamber is of sufficient volume to cause the deck, the pontoon and its load to float. The basin contains basin water that surrounds the pontoons, and has an open top, and the pontoons float in the basin water. The basin has a chamber of sufficient size to cause the basin to float in a body of water. Preferably, the basin has a wall sufficiently high to isolate the basin water from the body of water.

In some embodiments, the deck has at least two ends, the ends each being attached to a substantially fixed structure, thereby forming a bridge. Preferably, each of the ends contacts the substantially fixed structure, such that a vehicle may be driven from the deck to the substantially fixed structure.

The basin may have a plurality of walls, or a single substantially cylindrical wall. In some embodiments, the basin wall has one or more gates therein. The gate allows for the passage of pontoons and/or basin water into or out of the basin.

Another aspect of the present invention is a method for providing a floating bridge. The method includes providing one or more floating basins having basin water therein; providing one or more pontoons floating in the basins; providing, on the pontoons, a deck having an upper surface and at least two ends; and attaching each of said at least two ends to a substantially fixed structure, thereby forming a bridge between said fixed structures. In some embodiments, the deck is movable with respect to the pontoons. The floating structure may comprise a plurality of basins, which may contain ballast.

A further aspect of the invention is a method for providing a floating runway. The method includes providing one or more floating basins having basin water therein; providing one or more pontoons floating in the basins; and providing, on the pontoons, a deck for supporting the runway. The deck may be movable with respect to the pontoons.

In some embodiments, one or more basin walls has attached thereto a mooring line. The mooring line may be removably attached to a fixed structure such as a pier.

These and other aspects of the invention will be apparent to one skilled in the art in view of the following description and the appended claims.

DETAILED DESCRIPTION

The present invention provides floating structures, also referred to herein as “floating platforms”, that are useful, for example, for airports, bridges, causeways, manufacturing facilities, electrical generating facilities, recreational and entertainment facilities, residential structures, waste disposal facilities, and other facilities. The floating platforms are particularly suited for airports, including airport runways, and aircraft landing strips because the structure of the platforms reduces the degree of motion caused by conditions such as prevailing winds, currents and tides in bodies of water, as compared to conventional floating structures such as barges and ships. The floating platforms are also particularly useful for bridges between land masses or between fixed or floating manmade structures.

A floating structure as disclosed herein includes at least one deck; one or more flotation means attached to and supporting the deck; and one or more means for reducing the effects of currents in a body of water on the flotation means. The floating structure may also include a mooring means for restricting translational motion of the structure. The flotation means preferably includes one or more pontoons. The means for reducing the effect of currents may be a floating enclosed basin.

The floating structures are now described with reference to the drawings, which illustrate preferred embodiments of the invention. InFIG. 1is shown a simplified partial isometric view of a floating structure1.FIG. 2is a simplified exploded partial isometric view of floating structure1, with a partial cutaway. Floating structure1includes, generally, floating basin10, pontoons17, and deck11. Deck11is a generally rigid body, has a generally planar horizontal upper surface which includes runway12, and a rigid lower surface. The lower surface of deck11is preferably defined by the lower surfaces of ventral longitudinal ribs or beams13. Although ventral longitudinal beams13are shown inFIG. 2as separate from runway12, the separation is only for ease of understanding. In fact, runway12and ventral longitudinal beams13are preferably integrated in deck11. Referring specifically toFIG. 3, each ventral longitudinal beam13is preferably joined, at least at each end, and optionally at intervals along its length, to the adjacent ventral longitudinal beams13by diagonal cables or rods14, which serve to prevent rotation of longitudinal ribs13. Pontoons17are hollow bodies having an upper surface for supporting a load. Preferably, pontoons17have dorsal longitudinal beams18integrated into their upper surfaces to provide a load-bearing surface and to transfer the load to upright load bearing walls. Pontoons17may also have internal load-bearing vertical beams, walls or similar structures. Bound together by gravity, intermediate pontoons17and deck11are provided transverse beams16, which are mounted atop the longitudinal dorsal beams18of the pontoons, and upon which ride the longitudinal ventral beams of the deck. The load of deck11is transferred to transverse beams16, which in turn transfer the load to pontoons17. Ventral longitudinal beams13are preferably not rigidly attached to transverse beams16; rather, ventral longitudinal beams and transverse beams16are free to move horizontally with respect to one another, with the range of motion limited by stops27, for example. The dimensions and locations of stops27may be selected to limit the relative movement of the beams as desired. Similarly, transverse beams16are preferably not rigidly connected to dorsal longitudinal beams18, but are movable relative to dorsal longitudinal beams18within a range limited by additional stops27. Alternatively, ventral longitudinal beams13and transverse beams16may be rigidly connected together; similarly, transverse beams16may be rigidly connected to dorsal longitudinal beams18, so that deck11is rigidly connected to pontoon17. However, deck11is preferably movable relative to each pontoon17. In embodiments wherein deck11is movable, stops27can be located as desired, to provide a limit to the relative motion of deck11on pontoon17. Deck11may be supported on a plurality of pontoons17. Individual pontoons17preferably are not rigidly fixed to one another, but may move relative to one another. Individual pontoons17may move relative to deck11, while still supporting deck11. This freedom of motion reduces the stress that would otherwise be placed on deck11by movement of pontoons17. Pontoons17include a sealed or substantially sealed chamber28of a fluid having a density less than that of the fluid in which the pontoon floats. Typically, chamber28will be filled with air. The size of chamber28sufficient to cause pontoon17to float may readily be selected by engineers considering the mass of pontoon17, the load of deck11borne by pontoon17. Ballast19may be included in chambers28, as illustrated. Alternatively, pontoons17may include devices such as ballast tanks (not shown) that allow the degree of submersion of the pontoons17to be adjusted. The material of which pontoons17are constructed is not critical, and may be any material that can maintain the integrity of chamber28and support the portion of the weight of deck11borne by the pontoon. The pontoons may be constructed of, for example, reinforced concrete, plastics, composite materials, steel, or other metals. Pontoons17are attached to tethers61, which are in turn attached to wall62of basin10. Tethers61restrict the motion of pontoons17in basin10. It will be understood that other structures, such as bladders, padding or the like on wall62and/or on sides of pontoons17may be employed to restrict the motion of pontoons17.

Basin10is substantially in the form of a container having an open top, and serves to reduce the effects on the pontoons17of currents in a body of water23into which the flotation means and deck may be placed. Basin10has a substantially planar and square base and four generally planar and upright side walls, although other configurations of the base and walls are possible. Basin10may contain two or more separate walled chambers29, as illustrated in FIG.2. Basin10may have a double wall, similar to a double hull of a ship. Basin10includes a chamber29, which is enclosed and of sufficient size that, when filled with air or other selected fluid, to cause basin10, when filled with water (or other fluid) bearing pontoons floating thereon, to float in the body of water. Chamber29may be partially filled with ballast24, and the volume of ballast in the chamber can be adjusted to control the vertical position of the basin. Alternatively, basin10may contain ballast tanks or other structures to adjust the flotation of basin10. Basin10is restricted in its movement by being attached to mooring lines21, which may be attached to any fixed object of mass substantial enough to remain stationary when basin10is moved by currents. Such fixed objects may be pier, pilings, masses of concrete, or other mooring, driven into the floor of the body of water. Mooring lines21may be cables or wire, plastic, or other materials, chains of metal or composite, or other high-strength flexible structures and materials. The end of mooring lines21at basin10may be around driven spools to provide adjustment of the length as desired. In the embodiment shown, the water level in basin10is higher than the level of water in the surrounding body of water23, although it will be understood by one skilled in the art that other variations are possible, wherein the basin water level may be lower than or equal to the level of water in the surrounding body of water. Gates may be provided in the wall20for the passage of pontoons17into the basin10.

InFIG. 4is shown a side sectional view of an embodiment of a floating structure50including a roadway. The floating structure includes basins30, pontoons31, and a deck32. Deck32is a rigid body having a horizontal, planar upper surface, and has thereon a roadway surface38, and two end sections43,44. The roadway surface38may be paved or covered with any suitable material such as asphalt, gravel, concrete and the like. The floating structure is located in a body of water having a bed40, in which are buried mooring anchors41attached to mooring lines42. Mooring lines42have associated therewith devices for adjusting the length of mooring lines42, which devices may be driven spools. Each end section43and44of the floating structure contacts land43′ and44′ respectively. End sections43,44are preferably rotatably movable at their connections to deck32, at45,46, and rotatably and slidably movable at their connections to the land, at47,48. This permits slight movement of deck32in response to movement of basins30that is transmitted to pontoons31. However, because movement of basins30is not directly transmitted to pontoons31, movement of deck32is minimized.

Referring toFIG. 5, deck32integrally contains and is supported by ventral longitudinal beams33, which in turn are supported by transverse beams34. Transverse beams34ride atop the longitudinal beams atop the pontoons31. Basin30is similar to basin10ofFIG. 1, and contains basin water35, with pontoon31floating therein. The design of basin30may include the alternatives discussed above with respect to basin10. The water level of basin water35is higher than that of the body of water38. In the embodiment shown, the basin has a double wall36. Basin30has a sealed chamber39containing air or other suitable fluid to provide flotation and ballast37′ located therein. Pontoon31has a sealed chamber, with ballast37therein for adjusting flotation. It will be understood that pontoons31may be fixed with respect to deck30, or may have a range of motion, thereby reducing stresses on deck30.

The present invention also provides a method for providing a floating bridge. The method includes providing one or more floating basins as discussed above, having basin water therein; providing one or more flotation means, such as pontoons, floating in the basins; and providing on the pontoons a deck. If desired, the floating bridge may be assembled in a first location and transported to a second location for use. Basins may be provided with basin water at a first location, have one or more pontoons placed in the basin water and secured, and be transported to a second location. During transport, the basins may be temporarily attached together, by ropes or chains, which would then be removed at the second location. During use, basins30may be moored together by mooring lines such as ropes or chains, as well as individually moored to mooring devices such as piles or concrete masses buried in the floor of the body of water. A deck may be fabricated at another location and transported to the bridge location, such as by barge, or may be assembled at the bridge location. The deck is placed on the pontoons. A load transfer means, such as transverse beams of the above embodiments, may be provided intermediate the deck and the pontoons. The deck may be positioned so that stops on the deck and/or pontoons restrict the relative motion of the deck and pontoons. End sections are secured between the ends of the decks and the land. Alternatively, the end section may be a section of elevated roadway that suitably contacts deck32. End sections43,44may be fabricated together with deck32at a remote location, and may be maintained in a retracted or rotated position on deck32until such time as it is desired for the end sections to complete the roadway. The deck may have been previously provided with a roadway surface, or a suitable surface may be added after placement of the deck on the pontoons.

Also provided according to the invention is a method for providing a floating runway. The method includes providing one or more floating basins10having basin water at level22therein; providing one or more flotation means, such as pontoons17, floating in the basin10; and providing on the pontoons a deck11for supporting a runway12. Load transfer means, such as transverse beams16, may be provided intermediate deck11and pontoons17. The basins may be fabricated at a remote location and floated to a runway location and secured by mooring lines. The pontoons may be placed in the basins either at the runway location or previously. When the basins are properly positioned, load transfer means are placed on the pontoons, and a deck is placed on the load transfer means. A runway surface may have been previously provided on the deck, or may be added after placement of the deck on the pontoons.

As discussed hereinabove, a preferred means for reducing the effects of currents in a body of water on the floating structures described herein includes a basin. The basin floats in a body of water such as a river or ocean, and provides isolation of the deck from currents in the body of water. Basins10,30may contain basin water completely isolated from water in the surrounding body of water. Alternatively, the side walls of basins10,30may contain one or more through holes, so that the basin water flows in and out of the surrounding body of water. This reduces the load borne by the floating chambers in the basin. Flotation of the pontoons in a basin rather than directly in a body of water, such as a bay, river or ocean, provides reduction of effects, such as stress, imposed on the pontoons by forces such as wind or currents as compared to the stress exerted by such forces on a pontoon floating directly in a body of water. This reduces the motion of the deck. The basins may be moored in the body of water. Furthermore, while moored, the basin preferably maintains some freedom of motion. The motion can reduce or dissipate force exerted on the basin, such as by wind or water currents.

If it is desired to move the floating structure, the mooring lines of the basins may be disconnected from the stationary structures. The floating structure as a whole may then be transported by water to a new location. The deck may alternatively be removed, moved separately, such as by barge, to the new location, and replaced on the pontoons at the new location. The deck may be moved in a single section or divided into several sections at the time of removal, and then reassembled at the new location.

In preferred embodiments, the basin has a floor and one or more walls made of sturdy construction materials known in the art, such as, for example, reinforced concrete or steel. In some applications, preferred materials may be resistant to destructive effects such as corrosion, rust, dissolution, decay and breakage. However, the nature of the material or materials employed for the basin is not critical, and suitable criteria may be developed by one of skill in the art for the selection of appropriate material(s). The basin may have four walls and be square or rectangular. However, basins having other shapes may be acceptable or desirable for esthetic or functional reasons. For example, the basin may be substantially cylindrical, having one circumferential upright side wall. The floating structure may include a single basin, or multiple basins.

The preferred depth of a basin for use in accordance with the floating structures described herein is determined, in part, by the weight of the deck and any structures on the deck and flotation means, such as pontoons, and is sufficient to accommodate variations in buoyancy of the deck but sufficiently shallow to allow anchoring of the deck if desired.

The basin may have attached to it one or more mooring lines. For example, a rectangular or square basin may have four mooring lines, one attached at each corner. The mooring lines may be attached to a fixed, non-water borne, structure, such as a pier; or may, at an opposite end, be embedded in concrete and/or be buried in the floor of the body of water. The mooring lines may be removably attached to the basin and/or the fixed structure. The length of the mooring lines is preferably adjustable, and is sufficient to allow the basin to move in response to external forces such as prevailing winds and currents, thereby damping, and preferably substantially absorbing such forces and minimizing their effects on the deck. A driven spool mounted on the basin and associated with each of the mooring lines may be employed to adjust the length of the mooring lines. Alternative to, or in addition to, mooring lines, the basin may have an anchor affixed thereto.

The basin has walls sufficiently high to isolate the basin water contained therein from the body of water in which the basin floats. The walls of the basin may have one or more gates that can be opened to allow passage of the deck and pontoons into and out of the basin. The gates are preferably made of the same as or a similar material to the material of the walls, and preferably provide a substantially watertight seal when closed. The gates may open and close by hinges, or may open by being withdrawn into a void in the wall appropriately sized to accommodate the gate. Opening and closing of the gates is accomplished with a motorized drive or conveyor device.

The basin preferably includes one or more devices such as ballast tanks or containers that allow the degree of submersion of the basin to be adjusted.

The deck has at least one level comprising an upper surface and a lower surface. The upper surface may have one or more structures constructed thereon, such as one or more buildings, scaffolding, walls, and the like. If the structure is used as a runway, then the upper surface comprises one or more runways suitable for landing and takeoff of commercial, military, and/or private aircraft. The runway can be constructed using methods and technology known in the art. The uppermost surface of the deck is of a size sufficient to accommodate aircraft of the size and nature to be landed on the runway. For example, a runway may be about 100 meters wide or more, and about 1000 meters long or more. In addition to the runways, one or more service buildings may be on the upper surface of the deck. The deck supporting a runway is preferably supported on a plurality of basins, which may be arranged in one or more lines in a body of water. The use of multiple basins permits each basin to move independently in response to varying currents in the body of water. The movement of the pontoons in the basins, and the freedom of movement of the deck with respect to each of the pontoons, permits the basins to move independently of one another, within a limited range, without placing stresses on the structure of the deck.

In some embodiments, the floating structure includes two or more decks, including a top deck and one or more additional decks below the top deck. In embodiments in which the floating structure has more than one deck, the uppermost surface of the top deck can include a runway, and one or more lower decks can accommodate structures such as ticketing areas, administrative offices, storage, docks for accommodating ships transporting supplies and removing trash and other waste, baggage handling and sorting areas, waiting areas, shops and restaurants, and the like. If the floating structure has industrial facilities, such as manufacturing or power-generation plants, the structure may include manufacturing buildings, warehouse structures for supplies and/or finished goods, office space, and waste treatment and storage facilities for example. A power generating facility may be linked by high tension wires on supports on individual smaller floating platforms intermediate the power generating facility and the shoreline, or on a permanent or floating bridge or causeway. In embodiments in which the floating structure includes a roadway, the structure can have two decks, thus providing two road surfaces for use by, for example, vehicles traveling in opposite directions. In the embodiment ofFIG. 3, in place of or in addition to a roadway, the upper surface of the floating structure may include a supporting roadbed and tracks to accommodate rail transit, such as light rail or trains. It will be appreciated that a wide variety of structures may accommodated on the decks of the disclosed floating structures, and that the foregoing are merely exemplary.