Technical Field

The present invention relates to port terminals. More specifically, the invention relates to port terminals that are floating, such as floating container terminals or floating terminals or quays for other purposes.

Background Art

The areas available for ports are limited in many places. Many cities and urban areas have limited port capacity.

At least about 70-80% of the global trade is via containers. The globalization is to a major extent a result of “containerization”, allowing exporters to hire a series of standardized services on trucks, ships and trains for transporting from one location to another, reducing the cost for trading significantly.

No floating container terminal apparently exists in practice. Large floating terminals that have been planned but not realized are typically large pontoon like structures with a longitudinal central opening for one ship or two ships in parallel, with longitudinal floating structure on either side, wherein the longitudinal floating structures on the sides support cranes. Such large floating terminals are feasible in open waters for transshipment but not in confined port areas as operatively integrated and structurally coupled to existing quay structure or land.

The patent publications WO 2015/136086 A1 , JP 2005319903 A and JP 2002019965 A are found to represent prior relevant art, however, none of them describe or illustrates a floating port terminal of the hull height and wherein the port terminal for example is a container terminal configured for laying along an inclined land side along one of its longitudinal sides, or a port terminal that is a floating pier with draught of 0,25 or less.

There is an increasing demand for port terminals in general and container terminals in particular for reducing the shortage of port area and preferably also meeting other demands.

Summary of invention

The invention meets the demand by providing a port terminal, such as a container terminal, distinguished in that the port terminal is a floating steel structure comprising an outer steel hull, a top cover with rail structures for an STS crane and/or road structure for vehicles on or in the top cover, and mooring connected to anchors and/or land structure, preferably further comprising an STS (ship-to-land) crane, manned or remotely controlled, preferably an STS crane with controlled position and/or weight distribution adjusting when tightening or loosening the weight of a container slowly, to compensate for natural movements in roll and/or pitch of the steel hull of the port terminal of the invention, wherein the maximum or average draught of the outer steel hull is 0,5 or 0,4 or 0,3 or 0,25 or less than the height of the outer steel hull and wherein the steel hull as floating in operation preferably has a natural period of 0,5 or 1 or 2 seconds or longer.

The floating steel structure preferably include bulkheads, providing one or several compartments, and/or other structure providing increased rigidity. The port terminal of the invention is configured for service in confined port areas as operatively integrated and structurally coupled to existing quay structure or land.

Most preferably the port terminal is a container terminal comprising an STS crane for loading and unloading containers directly between ship and land, two parallel rails for the STS crane, extending longitudinally on top of the top cover or depressed to be flush with the top cover. However also other embodiments are relevant, such as a floating cruise or passenger terminal, an additional quay or pier or additional area for other purposes such as accommodation for living, storage, energy production or agriculture.

Preferably, said maximum or average draught of the outer steel hull is 0,25 or less than the height of the outer steel hull, preferably 0,24 or less, or more preferably 0,23; 0,22; 0,21 ; 0,20; 0,19, 0,18, 0,17, 0,160,15 or less. This is as measured with an STS crane in a central position. The trim range, that is the angular deviation in roll or pith due to STS crane operation within safe working load (SWL), preferably is within 1,4°, 1,2°, 1°, 0,8°, 0,6°, 0,5°; 0,4° degree or less with the STS crane positioned and operating along the rails, including and between operating end positions thereof. The trim range specified is the trim range at the position of the STS crane, as will be discussed below.

The maximum or average draught of the outer steel hull is 0,25 times or less than the height of the outer steel hull, calculated as the average draught of all immersed areas of the hull if the draught is not constant.

The trim range specified above is without active ballasting in the port terminal during operation of the STS crane, but merely by the design of the port terminal and especially the floating steel hull thereof. Preferably, the port terminal of the invention only comprises manual ballasting, not active ballasting, since active ballasting is less required for the preferred embodiments of the invention, as will be clear from the further description, and active ballasting is relatively expensive, and can be too slow for effective real time adjustments. Low draught and carefully designed sides of the steel hull are essential for providing the surprisingly low trim range, providing a stability making the port terminal feasible for operation with a heavy STS crane without any active stabilization of the port terminal by ballasting being required. The port terminal however preferably includes structure for ballasting between compartments therein, but as described, it is not required to have or use ballasting actively during operation of the STS crane, which represent a surprising significant saving.

The length of the floating steel structure is preferably 80 meter (m) or 100 m or longer, such as 120 m, 125 m, 126 m, 130m, 150m, 200m, 400 m or 600 m or longer.

As mentioned, the trim range specified is the trim range at the position of the STS crane. The floating steel structure can be above 600 m long and typically is longer than 100 m. The steel hull is however relatively elastic compared to a conventional ship hull. Said elasticity combined with very low draught and a natural period (resonance period) of above 2 seconds, preferably above 3 or 4 seconds, provides a port terminal of the invention behaving in the sea quite differently compared to a standard rigid, heavy barge or other typical floating structure. Comparable structures have higher weight, as evident by larger draught, and higher rigidity, meaning that the structure is stiffer or more rigid. Evidence of rigidity is the natural period. The rigidity of prior art structures is required to decrease the natural period to below 2 seconds, to reduce the risk for fatigue. However, with the port terminal of the invention, the natural period is above 2 seconds, the draught is far lower than normal, and the structure is less rigid than normal. These distinguishing features of the port terminal are surprising for the person skilled in the art, since increased rigidity is used to reduce the natural period to correspond to small waves and loads of low structural significance. However, due to good engineering practice, safety against fatigue can still be ensured for the port terminal of the invention. More specifically, full penetration butt welds and/or large radius of curvature, such as above 2, 4, 5 or 10 cm, in all positions with dimension changes, are preferably utilized, in areas of risk for fatigue, based on dynamical analysis and/or experience.

The width of the port terminal is preferably 20 m or wider, such as 25 m, 30 m, 35 m or 40 m or wider. Preferably the width is adapted to an STS crane SWL operative reach for allowing ship to shore (land) loading and unloading.

Preferably, the length is 4, 5, 8 or 10 times or more longer than the width.

Preferably, the floating steel structure comprises and can safely support an STS crane of weight of at least 500 metric tons, preferably heavier.

Preferably, the longitudinal side walls and/or end sidewalls of the floating steel structure has a slight curvature or inclination, adapted to tangent or be inside a circular shaped cylinder having centerline in the axis for roll of the floating structure, for the longitudinal sidewall inclination, and/or in an axis for pitch, for the end side walls. Said inclinations or curvature of longitudinal and end sidewalls are preferably inside or tangent any centerline for roll and pitch within the safe workload and the full span of operating position for the STS crane. This ensures that trim movements caused by crane operation and crane movements on the top cover are within the area and volume of a quay and/or land where the floating steel hull of the port terminal of the invention is located. The result is no or minimum impact loads and stress concentrations on the steel hull, thereby prolonging the service life.

Surprisingly, the structure with a large steel hull with low draught/height ratio provides a very stable structure with respect to pitch and roll caused by moving the center of gravity by movements and operation of an STS crane and/or load and/or vehicles. This is due to a surprisingly high up Tightening momentum when any inclination results by said movements and operation of an STS crane, load and/or vehicles. When the draught is very low, as obligatory for the port terminal of the invention, the relative difference in buoyancy on either side of the axis for pith or roll, becomes surprisingly high for even small pitching or rolling. Thereby, the apparently too large and heavy STS crane can operate safely.

The port terminal of the invention is feasible for positioning within or along existing quay structure or other land structure. Typically for most embodiments, the ship to be loaded or unloaded by the STS crane on the port terminal of the invention lay on one length side of the port terminal of the invention, on the outside, and containers can be loaded and unloaded from the landside, on the inside, on the other length side of the port terminal of the invention, to and from the ship.

The port terminal of the invention is also feasible as a pier or many piers extending out from existing quays or land, for example several parallel piers, preferably duly fastened to the existing quay or land and cross-anchored along and in the outer end of each port terminal pier to ensure no anchor line or anchor in shallow water and also reduced stress levels.

The port terminal of the invention is preferably cross anchored or/and slidably anchored to land. Cross anchoring means that the mooring or anchor line goes from one side or end of the port terminal and under the port terminal to an anchor under the opposite side or end of the port terminal or further outside. Anchor lines in open shallow water is thereby avoided and positioning is provided with reduced stress levels since some roll and pitch is relatively less restricted and forces go more in direction through larger parts of the structure, in the direction of inwards inclined anchor lines. Slidable anchoring can slide vertically, allowing vertical movements caused by tide, and/or move along the rotation direction for roll or pitch. Prior art floating terminals typically require the ship to be positioned inside the structure, or at least having structure on both ship sides, and large draught prevent use in shallow harbors and reduce the stability. In contrast, the port terminal of the invention is adapted for a harbor area, along existing quays or in openings between existing quays or along or coupled to other land structure.

In one embodiment, the port terminal has two pontoon like structures, one transverse or across in either end, for supporting longitudinal STS crane movements along longitudinal rails, when the STS crane is in or near end positions and/or said end positions are close to the end of the steel hull. In another embodiment, the port terminal has a box-like shape as seen from the longitudinal side and end, providing minimum draught and maximum up Tightening momentum in general, at minimum steel consumption. In some embodiments, the cross section of the port terminal of the invention is asymmetrical, shifting the roll axis nearer towards land for reducing land impact danger. In some embodiments, when area allows, the rails and safe operational movements of an STS crane extends to no nearer the port terminal ends than half the port terminal width distance, ensuring superior stability, by having significant volumes of structure providing buoyancy on all sides of the STS crane at all times. The invention includes port terminals with combinations of said embodiments, in all possible combinations, which represents further embodiments of the invention.

The port terminal of the invention preferably comprises an STS- crane with remote control and/or automation and/or artificial intelligence Al. Artificial intelligence is preferably included, for example by adjusting STS-crane position slightly when tightening or loosening the weight of a container slowly, to compensate for natural movements in roll and/or pitch of the steel hull of the port terminal of the invention. An autonomous STS crane or a remotely controlled STS crane can be preferable over a manned STS crane due to increased safety.

Some of the advantages of the port terminal of the invention are as follows:

Quays or terminals are provided at a reduced cost compared to piled quays or terminals. The investment cost is estimated to be 40 - 50 % lower than for a piled quay. No building site on the operation position of the port terminal since the structure is to be fabricated on a yard and is towed into operation position as fabricated. Accordingly, there is no requirement of a building site on the site of the port terminal, resulting in many months or even years without undue intervention on the site of the port terminal.

Areas not feasible for enlarged quay areas due to severe ground problems can have increased quay area, by the port terminal of the invention. The floating port terminal of the invention do not affect the soil condition or soil capacity on the site of operation.

The port terminal structure has a value after the service life has expired and can be towed to another site for further use, recirculation or upgrading. The invention also provides a further port terminal, such as a container terminal, distinguished in that the port terminal is a floating steel structure comprising an outer steel hull, a top cover with rail structures for an STS crane and preferably also road structure for vehicles on or in the top cover, and mooring connected to anchors and/or land structure, and further comprising an STS (ship-to-land) crane, manned or remotely controlled, wherein the STS crane comprises controlled position and/or weight distribution adjusting when tightening or loosening the weight of a container slowly, to compensate for natural movements in roll and/or pitch of the steel hull of the port terminal of the invention, and, the maximum or average draught of the outer steel hull preferably is 0,4 or 0,3 or 0,25 or 0,2 or less than the height of the outer steel hull and preferably the steel hull as floating in operation has a natural period of 1 second or 2 seconds or longer. The further port terminal has advantage in that the position and/or weight distribution adjustment is matched specifically, for providing increased stability and operation and lower stress level. In addition, remote control of the operation of loading and unloading containers and loads is facilitated, since all parameters can be balanced from the earliest design phase. Also, a further step towards autonomous loading and unloading of containers is taken. The invention also provides a further port terminal, arranged as a ro ro (roll on- roll off) quay, -pier or -ramp, hereinafter termed a ro ro quay, distinguished in that the ro ro quay comprises: a floating steel structure comprising a steel hull: a top cover with road or road like structure, or rail structures, on top or high elevation on the steel hull, for vehicles or trains to roll over; and mooring connected to anchors and/or land structure; and for some preferable embodiments, a flexible ramp structure between the floating steel structure and land; wherein the maximum or average draught of the outer steel hull preferably is 0,6 or 0,5 or 0,35 or 0,25 or less than the height of the outer steel hull, and preferably the steel hull as floating in operation has a natural period of 0,25 or 0,5 or 1 or 2 seconds or longer. The ro ro quay of the invention has advantage in increased stability, constant freeboard, easy operation, lower stress level and capacity for larger vehicles than typical pontoon ro ro ramps/quays, enabling surprising maximum capacity if designed with low nominal draught, and enabling use in very shallow waters. Apparently, no such ro ro quay exists on the market. The state-of-the-art ro ro quays are apparently fixed to and resting on the seabed or comprises low floating pontoons.

The terminology in the field of ro ro quays is unclear. In the context of the invention, the ro ro quay comprises a floating steel structure, comprising a steel hull. A liftable flexible bridge typically is arranged on the ship to be loaded and/or unloaded, and typically with a flexible bridge, or road or rail, connecting the floating steel structure to land or a quay or other solid ground. For many preferable embodiments, the ro ro quay of the invention comprises the bridge towards land and/or the bridge towards the ship, and hydraulic drives, rope winches, or other drives as required. In a preferable embodiment, the ro ro quay comprises the bridge to shore, which bridge preferably is mounted and/or designed to be flexible on the shore side. The elevation of the top cover or deck preferably always is below the elevation of driving into or out from the ship to be loaded and unloaded, and the elevation of the shore bridge on the shore side. With the floating steel structure, correct elevation is provided by natural buoyancy and design, but can preferably be adjusted by ballasting, in that compartments in the steel hull can be filled or emptied for water by operating a ballast pump that can be part of the ro ro quay, or external.

The port terminal and the further and additional port terminal of the invention preferably comprises manual ballasting.

Brief description of drawings Figures 1 - 4 illustrates an embodiment of a port terminal of the invention, as seen from the side, from the top, from the end and from an inclined view, respectively.

Figure 5 illustrates an embodiment of a port terminal of the invention with recesses in a longitudinal outer side of the outer steel hull, for shifting the axis for roll nearer land, in order to reduce the dynamic movements of the hull towards land.

Figure 6 illustrates further details of the embodiment of a port terminal illustrated in Figures 1-4.

Figure 7 illustrates an embodiment of a port terminal of the invention with a longitudinal box - like shape of the outer steel hull.

Figure 8 illustrates anchor details of the port terminal of the invention.

Detailed description of the invention

Reference is made to Figures 1-4, illustrating a port terminal of the invention, in the form of a container terminal 1. The illustrated embodiment is designed for fitting into an open area between two existing quay structures, with an inclined land filling on the land side between the quay structures. The longitudinal side of the container terminal towards the land filling is therefore inclined to fit over the inclined land filling.

The illustrated port terminal is a container terminal 1 , which is a floating steel structure comprising an outer steel hull 2 and a top cover 3, an STS (ship-to- land) crane 4, with rail structures 5 for the STS crane and road structure 6 for vehicles on or in the top cover. The port terminal further comprises mooring connected to anchors and/or land structure, wherein the average or maximum draught of the outer steel hull is 0,25 or less than the height of the outer steel hull.

Figure 5 illustrates another embodiment of a port terminal of the invention, with recesses 7 in the outer steel hull, for shifting the roll axis closer to shore in order to reduce dynamic movements towards the shore, and baffles 8, for damping dynamic movements.

Figure 6 illustrates further details of the embodiment of the container terminal illustrated in Figures 1-4. Fenders 14 on the longitudinal side, and bollards 15, are clearly visible on the outer longitudinal side where ships are loaded and unloaded. On the longitudinal side towards land, where an inclined stone filling exists, the side is inclined to at least matching the inclination of the stone filling, and the top cover extends out above land. The steel hull comprises a pontoon like transverse structure 16 inside each end, for allowing the STS crane to operate near the ends.

Figure 7 illustrates a port terminal with steel hull 2 shaped in substance as a flat rectangular box. Only part of the steel hull 2 is illustrated, namely a corner and end, with end 9, side 10 and waterline 11. The draught is about 0,2 times the height of the steel hull, corresponding to the height of the end 9 and side wall 10. The end is slightly curved, with center of curvature in the pitch axis with an STS crane (not illustrated in this Figure, for clarity) close to the illustrated end of the steel hull. Figure 8 illustrates anchoring, including cross anchoring of a port terminal of the invention. At least one anchor 12, preferably two or more anchors, are cross anchored by anchor line 13 to the opposite side of the steel hull 1.