GB2154637A - Harbour or port and improvements suitable for use therewith - Google Patents

Abstract

An artificial harbour or port comprises a plurality of floating units (9, 10, 12, 13), a causeway 4 connecting the floating units to the shore, flexible bridges 16 providing vehicle transportation surfaces linking the floating units and at least one floating unit and the causeway, and mooring posts 22' extending upwards from the sea bed, the floating units being connected to the mooring posts with freedom to rise or fall with the sea. The invention relates to the overall port and harbour and to such bridges per se, each bridge comprising an array of independently movable fingers accommodating relative movement of floating units by common or differential movement. <IMAGE>

Description

SPECIFICATION Harbour or port and improvements suitable for use therewith This invention relates to an artificial harbour or port and to certain improvements which are especially suitable for use therewith.

According to one aspect of the invention there is provided a harbour or port comprising; a plurality of floating units; a causeway connecting the floating units to the shore; flexible bridge means providing vehicle transportation surfaces linking the floating units, and at least one floating unit and the causeway; and mooring posts extending upwards from the sea bed, the floating units being connected to the mooring posts with freedom to rise and fall with the sea.

A harbour or port so constructed provides an effective solution to the problem of providing facilities in a location which is not suitable for development as a natural port or harbour.

Even in a location which is in principle suitable for development as a natural port or harbour the artificial port or harbour according to the invention may be preferred, being economical and quick to construct.

Each floating unit may comprise a plurality of ballast chambers and water admission means to selectively admit water to ballast chambers. Thus, when one side only of a unit is subject to a load water may be admitted to ballast chambers on the other side of the unit to effect balancing. Each floating unit is preferably a flat-bottomed structure such as a barge, pontoon or caisson.

Preferably the floating units are arranged in an array extending transversely to the causeway to form a sheltered region between the floating units, the causeway and the shore.

According to a second aspect of the invention there is provided a bridge linking relatively movable units, comprising: a plurality of independent fingers disposed in side by side relation to form a vehicle transportation surface; and joint means at each end of each finger, connecting the finger to a said unit, each joint means allowing relative movement between the finger and the unit, whereby movement of the fingers, either common or differential, accommodates relative movement between the units. Preferably each joint means comprises a pin transverse to the finger and a pin retaining conformation, movement of the finger perpendicular to the pin being hinging movement about the pin, and limited movement of the finger in other senses being accommodated by play between the pin and the retaining conformation.

This aspect of the invention is of general applicability but is particularly useful in the context of the port and harbour of the first aspect.

A preferred embodiment employs both the aspects of the present invention, the flexible bridges linking the floating units to each other and at least one floating unit to the causeway.

The invention will now be further described, by way of example, with reference to the accompanying drawings in which; Figure 1 is a view from above of an operational port according to the invention; Figures 2A and 2B together constitute an enlarged view of the handling region of the port shown in Fig. 1; Figure 3 is a further enlarged view, showing a mooring post connected between two floating units of the port; Figure 4 is a side elevation of a flexible bridge between two floating units; Figure 5 is a detail on sectin A-A of Fig. 6, of one end of a finger, forming part of such a bridge; Figure 6 is a plan view, partially cut away, of the finger; and Figure 7 shows a reinforced edge region of a floating unit, for attachment to a flexible bridge; The artificial port, as is shown in Fig. 1, has a handling region 2 linked by a causeway 4 to the shore 6.The handling region comprises an array of six floating pontoons 8 to 13, arranged as two side by side rows each of three pontoons arranged lengthwise. Thus the array is generally rectangular and the lengthwise direction of the rectangle is at right angles to the causeway. A sheltered region 1 4 is formed between the handling region 2, the causeway 4 and the shore 6.

Each pontoon is linked to each of its neighbouring pontoons by a flexible bridge 1 6. One pontoon 10 is linked by a flexible bridge 1 8 to a 'roll on-roll off' pontoon 20 which is located at the port end of the causeway 4.

The handling region is secured in place by six rigid mooring posts 22 in the form of piles driven into or otherwise secured to the sea bed. The mooring posts are located between the two rows of pontoons. As will be described in greater detail hereinafter, the pontoons are attached to the upper ends of the mooring posts 22 by chains of sufficient length to allow the pontoons to rise and fall with the sea.

Each pontoon is a flat-bottomed structure having a plurality of ballast chambers (commonly 1 6) formed by watertight compartments. When a pontoon is being loaded on one side a chamber on the opposite side may, under automatic control, be filled with water to keep the deck horizontal, and subsequently automatically emptied when the ballasting is no longer required.

The mooring posts 22, commonly known as dolphins, are steel box-section frameworks.

Between each mooring post 22 and each of its neighbouring pontoons is a crash fender 24. Each mooring post is connected to each of its neighbouring pontoons by three chains, as is shown in Fig. 3, which shows the mooring post indicated as 22' in Fig. 2. One chain 26 is shackled to an eye 28 on the pontoon 1 2 and to the adjacent corner 30 of the mooring post. The other chains 32 and 34 are shackled to respective eyes 36 and 38 on the pontoon 1 2 and to their nearest corner 40 of the mooring post. The chain 32 includes a turn buckle 42. The pontoon has reinforcement 41 in the region of each eye.

The eye 38 for the chain 34 is transversely aligned with the corner 40 but the eyes 28 and 36 are not located in transverse alignment with the mooring post 22'. The eye 36 is located so that the chain 36 extends at an angle of approximately 7.5 to the side 44 of the pontoon 1 2 whilst the eye 28 is located so that the chain 26 extends at an angle at approximately 12.5 to the side 44.

The arrangement described in relation to the connection of the mooring post 22' and the pontoon 1 2 is used for each such connection in the embodiment described, with the chains 26 connected to positions adjacent the ends of pontoons and the chains 32 connected to positions towards the middle of pontoons.

The mooring system is designed so that, should a vessel collide with the port, the energy is absorbed not just locally, but throughout the system. The chain arrangement in this embodiment has been designed with this requirement in mind and the rise and fall of the sea has not been a factor needed to be borne in mind in the design. However, when such a port is to be ussed in locations with substantial differences between high and low water it may be necessary to employ vertical sliding connections at chain ends.

The roll-on roll-off pontoon 20 is connected to the causeway by a ramp 43 hinged at respective ends to the causeway 4 and the pontoon 20. The pontoon may carry a swing bridge for connecting the pontoon 20 to a ship.

The causeway 4 comprises a semi-submersible structure with a large bottom chamber from the longitudinal sides of which smaller leg chambers extend upward. Water is admit ted to the bottom chamber until just the ends of the legs remain above the surface of the sea. A roadway is then constructed and secured at each transverse edge to one of the legs. The causeway shown has a roadway 45 and a walkway 46. The causeway may employ jack-up legs penetrating the sea-bed.

The bridges 1 6 connecting the pontoons must be able to accommodate various relative movements of the pontoon they link, e.g. the rising of one pontoon with respect to the other or the rising of just one part of a pontoon, causing the bridge to twist.

Each flexible bridge 1 6 comprises a number of independent fingers 47 arranged side by side to form a structure suitable for goods vehicles. As is shown in Fig. 6, each finger 47 is formed in this embodiment by three Ibeams 48 welded together along their length.

Each I-beam has welded to each end a rugged plate 50 formed with a downwardly-facing Ushaped recess 52 (see Fig. 5). Each recess engages a respective hinge pin 54 carried between a pair of plates 56 which are welded to the side 44 of a pontoon. The hinge pins at one end of a given bridge are axially aligned along the side of the pontoon, as shown in Fig. 7, and are perpendicular to the length of the fingers. The three pins of each finger end act as hinge members allowing the end to swing about the member for example when the other end rises and falls. The pins are moveover a slightly loose fit in the recesses and, therefore, a slight twisting movement of each finger with respect to the pins, and hence the pontoon, is permitted. The up and down and twisting movements can combine, so that each finger can swivel to a limited extent with respect to the other fingers and the pontoon.The bridge formed by a plurality of fingers as described above may undergo a considerable overall twist compounded from relatively small differences in the orientation of adjacent fingers, and is substantially torsion free within the limits to which it is subjected in use.

Fig. 7 shows in section the edge region 57 of a pontoon adjacent a bridge and in particular shows detail of local stiffening and support structure, comprising an array of stiffening plates 58, extending parallel to one another between the side 44 of the pontoon and an internal wall 60 parallel to the side 44, and cross-plates 62 between the stiffening plates 58. As is clearly shown in Fig. 7, the pincarrying plates 56 are welded to the side 44 at positions at which it is supported by the stiffening plates 56. Also as shown, one cross-plate 62 is fixed between each adjacent pair of plates 58 such that cross-plates extending from opposite faces of a given plate 58 are staggered from each other, being spaced from the side 44 by approximately one third and two-thirds respectively, of the distance from the side 44 to the wall 60.

In this embodiment pontoons 8, 10, 12 and 1 3 carry warehousing whilst pontoons 9 and 10 have open storage decks. Pontoon 11 has a facility for refrigerated containers 64.

Each of the pontoons may have a generator 65. On the warehouse pontoons these are preferably mounted on the warehouse roof.

Each pontoon carries, of course, floodlighting for night working. Pontoons 8, 9 and 10 carry outer wooden fenders 69. A typical size of the handling region 2 would be about 300 metres by about 70 metres.

The port described is made up from a number of modules which 30 are easy to assemble and disassemble. Thus, it may be used in one place and when no longer re quired may be dismantled and towed to a new location, and re-assembled there. It may merely be necessary to drive in new mooring posts if the old ones can not be removed from the sea-bed in a fit state for use in the new location.

Each pontoon has a number of towing bollards 66.

In other embodiments each mooring post is associated with a hydraulic take-up mechanism to allow the pontoons to rise and fall with the sea and/or lift the mooring posts.

It will be appreciated that although this specification has referred to use of harbours and ports in the sea, such structuires could also be used in lakes and rivers.

Claims (9)

1. A harbour or port comprising: a plurality of floating units; a causeway connecting the floating units to the shore; flexible bridge means providing vehicle transportation surfaces linking the floating units and at least one floating unit and the causeway; mooring posts extending upwards from the sea bed, the floating units being connected to the mooring posts with freedom to rise and fall with the sea.

2. A harbour or port according to claim 1, wherein the floating units are arranged in an array comprising two lines of floating units with the mooring posts located between the lines.

3. A harbour or port according to claim 1 or 2 comprising a plurality of ballast chambers within each floating unit, and water admission means to admit water to a ballast chamber on the opposite side of a 20 floating unit to that on which a load is applied.

4. A harbour or port according to any preceding claim wherein the floating units are arranged in an array extending transversely to the causeway to form a sheltered region between the floating units, the causeway and the shore.

5. A bridge linking relatively movable units, comprising: a plurality of independent fingers disposed in side by side relation to form a vehicle transportation surface; and joint means at each end of each finger, connecting the finger to a said unit, each joint means allowing relative movement between the finger and the unit, whereby movement of the fingers, either common or differential, accommodates relative movement between the units.

6. A bridge according to claim 5 wherein each joint means comprises a pin transverse to the finger and a pin retaining conformation, movement of the finger perpendicular to the pin being hinging movement about the pin, and limited movement of the finger in other senses being accommodated by play between the pin and the retaining conformation.

7. A harbour or port comprising: a plurality of floating units; mooring posts extending upwards from the sea bed, the floating units being connected with the mooring posts with freedom to rise and fall with the sea; a causeway connecting the floating units to the shore; and flexible bridge means linking the floating units, and at least one floating unit and the causeway, each bridge comprising a plurality of independent fingers disposed in side by side relation to form a vehicle transportation surface, and joint means at each end of each finger, connecting the finger to a said unit, each joint means allowing relatively movement between the finger and the unit whereby movement of the fingers, common or differential, accommodates relative movement between the units.

8. A port or harbour substantially as hereinbefore described with reference to the accompanying drawings.

9. A flexible bridge substantially as hereinbefore described with reference to the accompanying drawings.