SHIP WITH LONGITUDINAL REINFORCEMENT ARCHES

Description

1 Technical field of the invention

[0001] The present invention relates to a vessel, such as a naval vessel, a work vessel, a passenger transport vessel or a yacht.

[0002] The invention relates more particularly to the structure of such a ship. 2 State of the art

[0003] In the design and construction of ships, particularly long ships, it is necessary to optimize the weight and environmental impact of the ship during its years of operation, while the structure of the latter must remain robust.

[0004] It is generally considered that the greater the length and displacement (i.e. mass) of a ship, the more problems arise with longitudinal hull rigidity and fatigue due to the alternating (bow and counterbow) bending it undergoes.

[0005] To better distribute the stresses and optimize the strength of the ship's structure, the interior structure of the hull is generally reinforced, which can be likened to a "framework".

[0006] These vessels must also have operational capabilities adapted to the specific needs of their buyers.

[0007] EP 2 514 664 A1 describes a liner comprising a main structure delimited by a hull and its upper deck above which rises at least one superstructure comprising at least one arch which generally rises from the rear to the front, and which extends at least partly above the main structure, its opposite ends being integral with this main structure, so that said arch takes up at least partly the forces linked to its deformation. 3 Statement of the invention

[0008] The invention provides a ship comprising a hull and at least two decks (P1, P2, P3) including an upper deck (P1) and a lower deck (P2) extending below said upper deck (P1), said ship further comprising two reinforcing hoops extending on each of the lateral edges of said ship along at least a portion of said at least two decks (P1, P2, P3), the ship comprising an interior space forming a structural void, said interior space extending over the entire width of the ship and opening through an opening onto a side wall or the two opposite side walls of the hull of the ship, the two reinforcing hoops extending on either side of said interior space along the longitudinal axis of the ship, a first portion of the reinforcing hoops extending above said interior space and a second portion of the reinforcing hoops extending from the first portion towards the rear of the ship,the first portion of the reinforcing hoops extending at the level of said upper deck (P1) of the ship located above said interior space and the second portion of the reinforcing hoops extending at the level of said lower deck (P2) of the ship located below said upper deck (P1).According to the invention, said reinforcing hoops each extend from the lower deck (P2) and in that the area of ​​the lower deck (P2) located between the second portions of the reinforcing hoops has a bottom wall opening into said interior space by means of a bay which can be closed by at least one movable closing element.,

[0009] Thus, rather than reinforcing the hull structure, it is proposed to reinforce the ship's structure by implementing lateral stiffeners extending in the longitudinal direction of the ship, called longitudinal reinforcement hoops.

[0010] The invention thus proposes to separate the "skin" or "envelope" function (consisting of the deck and the hull) from the lateral stiffeners.

[0011] The invention applies more particularly, but not necessarily, to military vessels. It can also be applied to workboats, passenger boats, yachts, etc.

[0012] Furthermore, the invention also applies to ships with three decks.

[0013] The ship includes an interior space, like a hangar, occupying the entire width of the ship, and open on each side.

[0014] This hangar can house boats, an aircraft, or store one or more 20-foot containers, for example. Such a hangar can also house any other equipment or cargo that can fit within the hangar's dimensions.

[0015] Rather than a hangar, this interior space can be converted and used to accommodate passengers, for example.

[0016] This interior space is actually a structural hole.

[0017] To best distribute the stresses and optimize the structure's strength, while taking into account the structural void induced by this interior space, the reinforcement hoops are rigidly connected to the deck and the hull and longitudinally reinforce the deck and the hull in bending.

[0018] According to a particular implementation of the invention, said first portion of each reinforcement arch extends towards the front of the ship, and is extended by an end portion oriented towards the end portion of the other reinforcement arch.

[0019] According to a particular implementation of the invention, the second portion of the reinforcing hoops is extended by a third portion extending at least partially around an opening closed by a door and provided on the rear part of the hull of the ship.

[0020] According to a particular implementation of the invention, said reinforcement hoops have a variable thickness along the longitudinal axis of the ship.

[0021] According to a particular implementation of the invention, said reinforcement hoops are welded to the hull

[0022] Preferably, said reinforcement hoops are made of aluminum, metal or composite material.

[0023] Advantageously, said reinforcement hoops are hollow. 4 List of figures

[0024] Other characteristics and advantages of the invention will appear more clearly on reading the following description of embodiments, given as simple illustrative and non-limiting examples, and the appended drawings, among which: [ Fig. 1 ] : there Figure 1 is a schematic perspective view of the rear of a ship according to the invention implementing a hangar occupying the entire width of the ship and lateral reinforcement hoops; [ Fig.2 ] : there Figure 2 is a partial schematic view of an example of a lateral reinforcement arch behind which a light hangar is arranged; [ Fig. 3 ] : there Figure 3 is a partial schematic view of an example of a lateral reinforcement hoop; [ Fig.4 ] : there Figure 4 is a side view of a first type of vessel in accordance with the invention; [ Fig.5 ] : there Figure 5 is a side view of a second type of vessel in accordance with the invention; and [ Fig.6 ] : there Figure 6 illustrates a possible structure of reinforcing hoops; [ Fig.7 ] : there Figure 7 illustrates another possible structure of reinforcing hoops; [ Fig.8 ] : there figure 8 is a top view of a ship according to the invention showing a particular shape of the reinforcement hoops. 5 Detailed description of the invention

[0025] There Figure 4 is a side view of a vessel 1 in accordance with the invention, and more particularly of a military naval vessel of the patrol vessel type (or OPV for "Offshore Patrol Vessel" in English).

[0026] Ship 1 includes a hull 10, a propulsion system (not visible) and several stepped decks P1, P2, P3.

[0027] Ship 1 is approximately 70m long and hull 10 is made of aluminum.

[0028] Ship 1 incorporates an interior space in the form of a modular hangar 11 (called "Mission Bay") occupying the entire width of Ship 1, open on each side and closable by a system of curtains.

[0029] This hangar 11 can house and operate two 8.5m semi-rigid boats, but can also store a 20-foot container or any other similar equipment longitudinally, giving ship 1 the possibility of adapting to missions.

[0030] As is well known, on small ships, it is the local forces linked to the sinking of the hull or the water on the deck (hydrostatic) or the dynamic forces (accelerations, particularly vertical, "slamming", etc.) which are the dimensions for the structure.

[0031] For vessels of approximately 50m or more, the overall forces become dimensional, in particular the overall bending of the vessel. This bending is due to the differential between the distribution of weight along the vessel and the distribution of water pressure along the hull, both statically and dynamically.

[0032] The Applicant relied on both classification society regulations and internal developments to study this subject, with particular attention to cyclic fatigue phenomena.

[0033] For example, the Applicant has carried out seakeeping calculations in swells which provided data for finite element type calculations of the entire vessel and has carried out long campaigns to acquire behavioural and stress data on constructed vessels in order to recalibrate its models.

[0034] It appears that the integration of the concept of hangar 11 described above represents a risk with regard to the proper distribution of stresses and the strength of the structure. Indeed, hangar 11, due to its location in the middle of the ship and its very principle of open space, corresponds to a local weakening of the "ship beam", at the point where the expected stresses are the highest.

[0035] Considering the structural problem described in the previous paragraph, as well as aesthetic concerns, the Applicant came up with the idea of ​​a structural arch concept, called “Arch Bow” or “Rear Bow”.

[0036] These longitudinal reinforcement hoops 12, located symmetrically on either side of the longitudinal axis of the ship, on the rear of the superstructure, have the function of distributing the bending stresses along the ship beam, thus framing the structural void induced by the hangar 11.

[0037] The design of these 12 rear arches takes into account the transmission of overall bending forces between the decks of the ship.

[0038] These reinforcing hoops 12 extend along the lateral edges of the ship 1 along the longitudinal axis of the latter. They start from the upper deck P1 (shown in dotted lines) as an extension of the bulwark (first portion 121), going around the wheelhouse (but thicker at the rear), and slope down towards the rear, to descend towards the lower deck P2 (second portion 122 and third portion 123). Although this is not visible, the hoops 12 descend towards the main deck P3 (shown in dotted lines) and extend below the latter inside the hull 10.

[0039] These reinforcement hoops 12 are in the form of a hollow profile.

[0040] The first portion 121 of the reinforcement hoops 12 extends above said hangar 11 and the second portion 122 of the reinforcement hoops 12 extends from the first portion 121 towards the rear of the ship.

[0041] The first portion 121 of the reinforcement hoops 12 extends to the level of the upper deck P1 of the ship 1 which is located above said hangar 11 and the second portion 122 of the reinforcement hoops 12 extends to the level of the lower deck P2 of the ship 1 located below the upper deck P1.

[0042] These reinforcement hoops 12 are visible (shape and color) from the side and seen from the rear of the ship 1, and emphasize the modular and practical, even utilitarian, function of the ship while fulfilling the stress transmission function at the origin of the idea.

[0043] These lateral reinforcement hoops 12 extend along the longitudinal axis of the ship 1, on either side of said hangar 11.

[0044] These reinforcement arches 12 form two thick and hollow lateral boxes housing technical or circulation functions, the space 13 located in the middle between the arches 12 being an open and modular rectangular space: either to close it with a hangar H intended to accommodate a helicopter as illustrated in the detailed view of the Figure 2 (it could also accommodate an aerial drone, not shown in this figure), or open and allowing the reception of a container C (20 feet, for example) or something else as illustrated in the Figure 1 .

[0045] In the first case, the structure of the light H-hangar is preferably separated from the main structure, for example by building it like a container with folded sheet metal and a supporting structure.

[0046] The bottom of the lower deck P2 and of space 13 can be open and have a bay 14 which can be closed by a roller shutter, for example, the bay 14 opening onto the interior of the hangar 11.

[0047] The design of two longitudinal reinforcement arches 12 in addition to hangar 11 ensures structural continuity in overall bending.

[0048] In terms of design, this helps to highlight the ship's modularity function.

[0049] The two lateral reinforcement arches 12 can extend vertically onto the upper decks P1 and lower decks P2, and can integrate circulation, ventilation or other areas, and can allow: have a modular space on the lower deck P2 between the two reinforcement arches 12: drone hangar or open space (for placing a 20-foot container); have two rectangular modular spaces of 30 m2 on the upper deck P1 (modular space, diver's room, etc.).

[0050] Passing the stresses through the outer skins of the ship's structure (planking or cores) and the lateral arches 12 (sole) can eliminate the need for a structure between these elements.

[0051] The reinforcement hoops 12 are preferably hollow, and have a substantially rectangular section with possibly cut planes, and chamfer or fillet type connections ( Figures 6 and 7 ).

[0052] For example, the height of the reinforcement hoops 12 is around 1.20m and their width can vary between 0.20m and 1.20m in the longitudinal direction of the ship.

[0053] The principle of the invention remains valid in the case of a solid profile, although it is more complex to manufacture in these dimensions and less interesting in terms of mass / resistance ratio.

[0054] The 12 reinforcement hoops are made of marine-grade aluminum, sheets and profiles.

[0055] Manufacturing by assembling specific profiles (aluminum) can be considered.

[0056] The reinforcement hoops 12 are rigidly welded to the hull forming a recess.

[0057] We can imagine that the area of ​​the lower deck P2 between the reinforcement arches 12 is modular: we can install a light hangar there (which is not structural), for example to house a USV, to house and store equipment, to accommodate a standard 20-foot or 10-foot container.

[0058] Most ships of this type don't have a very sophisticated aesthetic. The illustrated solution offers a new and sophisticated aesthetic.

[0059] It turns out that in ships of this type, or in military ships in general, if an aesthetic concern has been incorporated, it is often at the front of the ship. Generally, the rear part is very technical, and is treated from a functional point of view with large flat, horizontal (decks), transverse and longitudinal surfaces with a "box" effect and violent transitions between the surfaces.

[0060] The proposed concept of reinforcing arches allows to aesthetically soften the transition between the zones, and offers a gently sloping line towards the rear, marked by the thickness of the structure and possibly the color and texture of this area which allow to aesthetically link the volumes along the ship and give more visual impact to the front by avoiding abrupt breaks in line at the rear which attract the observer's eye.

[0061] This reinforcing arch concept can be extended towards the front of the vessel. Indeed, as illustrated in the figures, the arches 12 are located at the rear of the superstructure, with a structural transition zone towards the side bulwarks surrounding the wheelhouse. Since the stresses passing through the arches are significant, the transition is difficult to manage structurally.

[0062] On the top view of the figure 8, the reinforcing hoops 12 extend structurally towards the front of the ship, or even as far as the front part of the bulwarks where this protection closes transversely. The end portions 120 are curved towards the inside of the ship 1 to protect the wheelhouse and the crew from the effects of the sea and the wind at the upper deck level. This extension can be aesthetically consistent, the entirety of the hoops and the bulwark being able to have the same color / texture.

[0063] It is important to note that the invention is not linked to the presence of the transverse hangar 11.

[0064] If we can consider that in the event of the presence of hangar 11, or any other large opening in the sides of the ship beam, the invention makes it possible to stiffen the ship beam, it also allows it without the presence of this type of "hole" in the structure (may be through or not).

[0065] This is illustrated on the Figure 5which shows another type of ship 1 without hangar 11 but implementing reinforcement hoops 12 as described previously.

[0066] THE Figures 6 and 7 illustrate two possible structures of reinforcement hoops in accordance with the invention. On the Figure 6 , the arch 12 takes the form of a lattice. On the Figure 7 , the arch 12 has openwork portions.

[0067] The invention can be applied to ships of different sizes, and in particular large ships.

[0068] This may be, for example, transport vessels, whose length is approximately 120 to 150m, for which the hoops can be implemented, along the length of the vessel, but also going down to the rear to the freeboard deck, framing the rear door, generally large, which closes this type of vessel and allows the embarkation and disembarkation of vehicles (this door having no structural function).

[0069] The reinforcement hoops are preferably made of aluminum. This material has the advantage of significantly reducing the weight of the hulls and therefore mechanically reducing fuel consumption and CO2 emissions.

[0070] Aluminum is also rustproof, which helps reduce operating costs.

[0071] It should be noted that while the invention is particularly interesting with an aluminum construction, due to its relatively low bending rigidity compared to steel, the reinforcement hoops can be made from any type of material used for shipbuilding, including aluminum, steel and composite materials.

[0072] In a particular example, the transverse hangar is 11m long, 5.60m high and about 10 to 11m wide (transverse to the ship's axis) on this ship.

[0073] As another example, for a larger ship, the transverse hangar is approximately 15m long, 13m wide and 5m high.

[0074] The concept of the invention can be implemented on a pleasure boat, such as a motor yacht, for example, a work boat, a passenger transport boat, a yacht, etc.

[0075] Rather than a hangar, the interior space of the ship can be converted and intended for accommodating passengers, for example. This interior space occupies the entire width of the ship 1 and can be open on one or both sides. Each opening can be closed by a fixed or movable closing device between an open and a closed position.

Claims

1. A ship (1) comprising a hull (10) and at least two decks (P1, P2, P3) including an upper deck (P1) and a lower deck (P2) extending below said upper deck (P1), said ship (1) further comprising two reinforcing arches (12) extending over each of the lateral edges of said ship (1) along at least part of said at least two decks (P1, P2, P3), the ship comprising an interior space (11) forming a structural void, said interior space (11) extending over the entire width of the ship (1) and leading to an opening on a side wall or the two opposite side walls of the hull (10) of the ship (1), the two reinforcing arches (12) extending on either side of said interior space (11) along the longitudinal axis of the ship (1), a first portion (121) of the reinforcing arches (12) extending above said interior space (11) and a second portion (122) of the reinforcing arches (12) extending from the first portion (121) towards the rear of the ship (1), the first portion (121) of the reinforcing arches (12) extending at said upper deck (P1) of the ship (1) located above said interior space (11) and the second portion (122) of the reinforcing arches (12) extending at said lower deck (P2) of the ship (1) located below said upper deck (P1), characterised in that each of said reinforcing arches (12) extends from the lower deck (P2) and in that the area of the lower deck (P2) located between the second portions (122) of the reinforcing arches (12) has a bottom wall opening into said interior space (11) via a bay (14) which can be closed by at least one movable closing element.

2. The ship (1) according to claim 1, characterised in that said first portion (121) of each reinforcing arch (12) extends towards the front of the ship (1), and is extended by an end portion (120) oriented towards the end portion (120) of the other reinforcing arch (12).

3. The ship (1) according to one of claims 1 and 2, characterised in that the second portion (122) of the reinforcing arches (12) is extended by a third portion (123) extending at least partially around an opening closed by a door and formed on the rear wall of the hull (10) of the ship (1).

4. The ship (1) according to one of claims 1 to 3, characterised in that said reinforcing arches (12) have a variable thickness according to the longitudinal axis of the ship (1).

5. The ship (1) according to one of claims 1 to 4, characterised in that said reinforcing arches (12) are welded to the hull (10).

6. The ship (1) according to one of claims 1 to 5, characterised in that said reinforcing arches (12) are made of aluminium, metal or composite material.

7. The ship (1) according to one of claims 1 to 6, characterised in that said reinforcing arches (12) are hollow.

8. The ship (1) according to one of claims 1 to 7, characterised in that said interior space (11) is a hangar.