Underwater structure system forming a reef.

Abstract

The invention relates to an underwater reef-forming structure system, intended to be installed underwater. The structure forms a hollow enclosure extending longitudinally. The system comprises a plurality of tympana (2) arranged transversely to form a plurality of transversely partitioned habitat sections along said enclosure. Figure to be published with the abbreviation: Fig. 5

Description

Technical field. The present invention relates to an aquatic structure system forming a reef. It concerns the technical field of artificial reefs, that is, structures intentionally submerged, particularly for the purposes of physical protection of a location (against waves and wind), fisheries production, or recreation, for example, the intentional creation of waves or modifications to the environment for the purpose of exploiting a concept such as surfing waves. In particular, in addition to these main functions, this aquatic structure system is designed to be colonized by attracting numerous species of fish and crustaceans. State of the art. Generally speaking, underwater artificial reefs comprise a collection of diverse structures deliberately submerged to create a new habitat designed to attract, establish, and support aquatic organisms (flora and fauna). These structures can also play a role in protecting against coastal erosion or provide a site for recreational activities (scuba diving, fishing, surfing). A reef can be made up of a single unit (module) or an assembly of similar or different unit elements. They are generally made of concrete, more rarely of steel or synthetic polymers. Despite the growing international development of artificial reef immersion projects, the design and implementation processes of current models have various drawbacks. Firstly, in areas subject to strong hydrodynamics, artificial reefs undergo significant scouring in the contact zone between the structure and the soft bottom, as well as subsidence, which can cause a more or less complete disappearance of the reef under the seabed and thus limit the lifespan of artificial reefs. In many cases, artificial reefs are made from new or recycled materials, diverted from their original use (such as sanitation or civil engineering). The use of these often prefabricated materials is appealing, particularly due to the generally low cost of individual components, but the final result is disappointing in most cases. Indeed, the preparation of the original materials for immersion and the difficulty of achieving the desired characteristics... Precise specifications with elements having limited characteristics severely hinder this type of project. Sometimes, artificial reefs are specifically designed and constructed, but in such cases, these structures have at least one of the following drawbacks: limited habitat diversity for aquatic organisms, lack of fully protected areas for mobile wildlife, and risk of entanglement for artisanal fishing gear (such as fixed nets). In particular, artificial reefs designed to act as barriers preventing the illegal use of destructive trawling gear (especially trawls) in certain geographical areas generally exhibit all of these disadvantages. Furthermore, it is desirable that such an underwater structure should also act as a wave break or wave management system as waves approach the shoreline. Currently, wave breakers made of geotextiles (which suffer significant tearing damage due to vandalism, ship traffic, etc.), using riprap, or floating concrete pontoons are known, but none of these structures allows for combining such a wave break function with the specific functions of a reef that provides habitat for aquatic species. Finally, the use at sea of ​​significant logistics and handling resources (pontoons, large barges, cranes, etc.) to submerge heavy non-floating artificial reefs significantly increases the financial cost of artificial reef immersion projects. Examples of artificial reefs include documents FR 2129607 and WO 8705645. The invention aims to remedy this state of affairs. In particular, an objective of the invention is to propose a system of underwater structures capable of ensuring both the function of a wave break, or of managing waves approaching the shoreline, and the usual functions of a reef, in particular with regard to aquatic species. A key objective is to offer a low-maintenance underwater structure system, or even one requiring no repair or maintenance, so that the system is particularly stable over time. Another objective is to identify reference areas to establish a benchmark perimeter for the evolution of marine ecosystems. A complementary objective is to propose an underwater structure system that generates no, or almost no, scour or settlement during its cycle of use. Another objective is to propose an underwater construction system that does not require significant consumption of natural resources. A complementary objective is to propose an underwater construction system presenting a very low carbon impact, or even a zero carbon impact. Presentation of the invention. It has thus been observed by the applicant, after various experiments and manipulations, that it is particularly interesting to create an underwater structure that reduces or even eliminates the destructive impact of wave energy and coastal erosion while avoiding the disappearance of underwater species, or better yet, protecting them. Furthermore, all the aforementioned problems related to prior art processes and systems are solved thanks to the present invention. The solution proposed by the invention is an underwater structure system forming a reef, intended to be installed underwater, the structure system forming a hollow enclosure extending longitudinally, the enclosure being formed by a plurality of voussoirs defining a roof comprising openings and having a transverse section in the shape of a semicircle or nearly a semicircle, a plurality of longitudinal beams arranged on the ground in the form of two parallel bands, the lower ends of the voussoirs being respectively mounted on at least one beam, The system is remarkable in that it comprises a plurality of tympana arranged transversely to form a plurality of transversely partitioned habitat portions along said enclosure. It can be noted that the system of works forming a hollow enclosure extending longitudinally is located parallel, perpendicular or in random orientation with respect to the shores. The roof structure defined by the plurality of voussoirs forms a tunnel itself comprising a plurality of living spaces. Hereafter, the invention is presented in relation to the voussoirs, bearing in mind that at least two voussoirs form a cross-section of the tunnel, these two voussoirs advantageously being of identical shape and dimensions. Of course, the voussoirs may have different shapes and / or dimensions, provided that, when joined together, they form a tunnel-like roof structure or something similar. The underwater structure system forming a reef according to the invention makes it possible in particular to relieve the impact of swell, waves or tides. It can also be noted that these portions of habitat define one or more tunnels likely to form one or more lines, possibly joined and / or superimposed on each other. The expression "transversely partitioned habitat sections" refers to the fact that the hollow enclosure extending longitudinally, along an X'X axis, includes a A plurality of chambers whose walls are formed, on the one hand, longitudinally, by at least one voussoir and, on the other hand, transversely (perpendicular to the longitudinal axis), by at least two solid walls—without any openings for communication—or nearly solid walls designated by the term "tympanum." Each of these chambers or transversely partitioned habitat sections is intended, by virtue of the openings in the voussoirs, to house identical or preferably different aquatic species, the latter being selected by their size relative to said openings. Without being exhaustive, the advantages and characteristics / properties of the invention are presented below, namely: low, or even very low, maintenance; a (re)accumulation of sediments on the coastline or at least a limitation coastal erosion; a preservation of its original position (according to the x, y and coordinates) Z) off the coastline or emerged coast; a base for mounting and / or securing other underwater structures or aquatic; no environmental or human degradation; selective nurseries or shelters by calibration of certain species. In its broadest sense, the present invention is defined by the combination of: voussoirs forming tunnels and constituting a barrier absorbing energy of the swell or operating wave management approaching the coastline or the coast, with tympanic membranes separating transversely, in an airtight / total manner or virtually airtight / total, the various ecological chambers and taking into account the mechanical stresses experienced by the voussoirs. Other advantageous features of the apparatus that is the subject of the invention are listed below. Each of these features may be considered alone or in combination with the notable features defined above. Each of these features contributes, where applicable, to the resolution of specific technical problems defined further in the description and in which the notable features defined above do not necessarily participate. The latter may, where applicable, be the subject of one or more divisional patent applications. Advantageously, the tympanums are mounted on the stringers. The stringers receive the tympana and anti-scour mats described below so that the tympana and mat are mounted or fixed onto the stringers. Preferably, said system comprises a plurality of piles driven into the ground, said piles being fixed to the stringers or fixing the latter to the ground. Thus, advantageously, the piles serve as anchors and support the stringers, which in turn support the spandrels and serve as fixing points for the scour mats briefly defined below. The spandrels are advantageously locked onto the stringers by any mechanical means and receive the voussoirs anchored thereto, advantageously by any mechanical means (screws, bolts, nails, or the like). In other words, the anchors or piles serve to support the stringers by anchoring them in the ground and also allow to maintain a constant elevation over time for the structure system. According to a preferred embodiment, the voussoirs, advantageously also the aforementioned tympana, are made of fiber-reinforced concrete. Advantageously, for at least two habitat portions, the openings of the voussoirs of each of the two habitat portions have diameters or opening sections that are different from each other so as to be suitable for accommodating aquatic species of different sizes. Advantageously, the eardrums have a thickness of between ten and one hundred centimeters, preferably between forty and sixty centimeters. Advantageously, the voussoirs have a thickness of between five and fifty centimeters, preferably between twenty and thirty centimeters. In a preferred embodiment, the system further includes scour protection mats extending across the ground from the foundation beams outside the living areas. These scour protection mats may, of course, be omitted depending on the material encountered. Anti-scour mats prevent sea turbulence, created by the underwater structure system, from eroding the sand upstream and downstream of the reef formed by said structure system, and thus limit or eliminate scour. Advantageously, according to a preferred embodiment, a section of the roof consists of two voussoirs of identical dimensions and shape, the two voussoirs being joined together to form said section of roof. Thus, according to a preferred embodiment, a voussoir consists of one of the elements of the cover section, also referred to as the "tunnel wall". Preferably curved in shape, these voussoirs may be identical to form the tunnel or of different shapes or dimensions both along a section of the wall and along its length. According to advantageous features of the invention, the height of said system relative to the ground is at most ten meters and the upper end of the voussoirs is disposed at most one meter from the water surface at its so-called level. It can be noted that the structure system according to the invention can also be partially emerged out of the water, as can of course be defined as being more than one meter from the water surface level. Brief description of the figures. Other advantages and features of the invention will become clearer upon reading the description of a preferred embodiment which follows, with reference to the attached drawings, which are provided as illustrative and non-limiting examples and on which: [Fig.1] is a schematic perspective representation of an embodiment of the underwater structure system according to the invention. [Fig.2] is a schematic view of the structure system, visible in [Fig.1], placed in an aquatic environment. [Fig.3] illustrates with a schematic view the construction of an underwater structure system according to the invention. [Fig.4] is a schematic representation showing the placement of the voussoirs on the tympana and stringers. [Fig.5] is a schematic view of an almost completed underwater structure system according to the invention. [Fig.6] is a schematic photograph illustrating one method of constructing a tympanum. [Fig.7] is another view of the tympanum shown in [Fig.6] on which some of its dimensions are noted. Description of the implementation methods. Figure 1 presents a complete underwater structure system outside its aquatic environment where it is to be deployed and secured, but without the tympanums. Due to its function as a wave break or wave management system, the present invention is particularly intended for placement along the shoreline of an ocean or sea, but when the artificial reef function is paramount, the underwater structure system can also be placed near the shores of a lake or similar body of water. The underwater structure system comprises at a minimum voussoirs 1 and tympana 2. The voussoirs | have the main function of managing swell and waves and of forming, in cooperation with the tympana 2, the partition or wall of the different chambers or portions of habitat 3. For this latter function, the voussoirs 1 have a plurality of orifices or openings 4, holes or recesses allowing aquatic species to enter (and exit) these different portions of habitat 3. The number of these orifices or openings 4 varies according to their size and the species or species of aquatic species that one seeks to protect so that this number can be between four and one hundred, or even more if the dimensions of the voussoirs 1 allow it. In the example chosen to illustrate the invention, the voussoirs 1 have a semicircular cross-section—perpendicular to the longitudinal axis X”X visible in Figures 1 and 5. As can be seen in particular in [Fig. 3], each voussoir 1 comprises, to form a complete section defined as a voussoir 1, two identical faces or parts 10, 11 to be fixed together to form the voussoir 1. Naturally, such an arrangement is primarily intended to facilitate the logistical and assembly operations of the underwater structure system, so that if the dimensions of the voussoir 1 are relatively small, it is delivered as a single semicircular block. The underwater structure system includes stringers 5 consisting of longitudinal support elements extending along the X°X axis and possibly for fixing the voussoirs 1 and the tympana 2. These stringers 5 have here an L-shaped cross-section with their longest length resting on the ground S while a stop or protuberance is intended to allow the lower ends of the voussoirs 1 to come into contact and butt against each other. Indeed, it is possible that the voussoirs 1 are not mechanically fixed to the stringers 5, even if this method of embodiment is not preferred. Figures 1 and 2 also show two anti-scour mats 6 extending outwards from the stringers 5 relative to the habitat sections 3. These anti-scour mats 6 are not fully unrolled here, but it can be assumed that their free ends—those located opposite the stringers 5—include a mound, elevation, mound, or similar feature, in order to anchor this free end of the mat 6 in the soil S or to form a ballast ring 7, visible in Figure 5, whose function is to keep the mat 6 stretched and to physically protect it at this free end. It should be noted that since the mat 6 is not present in the habitat sections 3, these sections 3 may contain elements that were originally present and / or added elements such as rocks, stones, or algae on the soil S. Figure 3 shows the construction site for the installation of the underwater structure system according to the invention, with cranes 20 and an operator 1 in the water or aquatic environment. In Figure 3, compared to Figures 1 and 2, a spandrel 2 and two piles 8 fixed respectively to two parallel facing beams 5 can also be seen. The piles 8 can be at least one meter long and up to several meters, the height of the voussoirs 1 relative to the ground S being likely to correspond to the length of the piles 8, in other words, their penetration depth in the ground S. These piles 8 can have a plurality of conical profiles positioned one after the other along the pile 8 to improve their anchoring function in the ground S. The tympanum 2 comprises lateral ends 9 designed to be mounted, positioned, or even fixed onto the stringers 5. Thus, these ends 9 of the tympana 2 advantageously have a shape and cross-section complementary to the cross-section of the stringer 5 on which they are mounted / positioned / fixed. These tympana 2 are either solid or perforated but closed by a grille or door; that is to say, the tympana 2 completely obstruct a lateral partition to form one of the walls of a portion of the habitat 3 within the enclosure of the underwater structure system according to the invention. As can be seen in [Fig. 4], in one embodiment, two tympana 2 are joined so that each of the two tympana 2 forms a dedicated wall of the considered portion of the dwelling 3. Of course, a single tympana 2 is sufficient to close off a portion of the dwelling 3, so it is useful to join two tympana 2 when there is a difference in height between two contiguous portions of the dwelling 3 in order to support and secure the voussoirs of each of the two portions. The tympana 2 have openings 4 around their circumference or periphery so as to secure the voussoir 1, at its two longitudinal ends, to a tympana 2 using bolts, screws, or any similar mechanical means. The tympana 2 are advantageously secured by any mechanical means to the stringers 5. Figures 6 and 7 present an alternative embodiment of the tympana 2. In this variant, the tympanum 2 comprises the same hemispherical shape, of which only the contours or periphery 30 are formed and have a relatively significant thickness. The central portion 31 of the tympana 2 then presents various technical solutions, ranging from a pane of glass or an obturating wall, advantageously of little thickness compared to the periphery 30, to a mesh structure, not visible in Figures 6 and 7, allowing for a greater or lesser degree of fluidic communication between two adjacent habitat portions 3. In this latter case, the mesh obstructs the central portion 31, advantageously covering at least 50% of its surface area. Figure 7 illustrates more specifically the dimensions, expressed in millimeters, of such a tympanum 2, by way of example. Thus, the radius of the hemispherical tympanum 2 is equal to 3 meters. The periphery or contour 30 of the tympanum 2 has a thickness of 640 millimeters (mm). The ends 9 of the tympanum 2, intended to come into contact or abut against a stringer 5, have a recess 32 with a square cross-section and sides of 200 mm, particularly visible in Figure 7. The voussoirs 1 are advantageously made of fiber-reinforced concrete, that is, concrete to which fibers of a different nature, size, and shape than those found in concrete have been added. Distributed homogeneously throughout the mix, these fibers improve certain characteristics of the concrete, particularly its tensile strength. It should be noted here that the spandrels 2 can also advantageously be made of fiber-reinforced concrete, using fibers identical or not to those of the voussoirs. There are different types of fibers, each with varying impacts on concrete. For example, they can improve certain concrete characteristics such as flexural strength or crack limitation. Added at a rate of 0.5 to 2% per cubic meter (m³) of concrete, these fibers possess intrinsic characteristics: composition, size, and shape. There are different categories of fibers: - Metallic fibers: typically made of steel, cast iron or stainless steel. These fibers offer good resistance to bending, tension and breakage and help reduce the size of cracks. - Organic fibers: typically acrylic, aramid, carbon, Kevlar, polyamide, polypropylene / polyethylene (PP / PE) or polypropylene (PP). These fibers are flexible, which improves their workability. - Mineral fibers: typically basalt, mica, glass, or wollastonite. These fibers offer excellent fire resistance and good thermal insulation. They allow for the construction of very thin walls. Within the framework of the present invention, the fiber-reinforced concrete of the voussoirs 1, or even of the tympana 2, preferably uses organic fibers, preferably carbon or polyamide PP / PE. The installation of the complete underwater structure system, including its main voussoir-tympanum elements 1-2 and its optional / advantageous elements, according to the invention, follows the successive steps mentioned below: bathymetric survey; ground levelling $; installation of the 8 piles for anchoring; pile driving 8; manufacturing of concrete elements, advantageously in fibre-reinforced concrete; installation of the stringers 5; tympanic membrane placement 2; installation of voussoirs 1; installation of anti-scour mats 6 and filling of ballast tubes 7. The underwater reef-forming structure system according to the invention is particularly suited to coastal management and the management of exploitable marine resources. It protects the seabed from the destructive action of trawling fishing gear and creates a network of effective shelters for numerous species. It also allows for the construction of aesthetically pleasing and original underwater structures likely to attract scuba divers. Furthermore, its primary function is to be used near the shore to create protective structures. coastal protection against erosion or to control wave formation, particularly for surfing, sea kayaking or kitesurfing, but also the development of marine ecosystems for both sport and scientific scuba diving. Although the invention has been described in connection with several particular embodiments, it is clearly evident that it is by no means limited to them and that it includes all technical equivalents of the means described as well as their combinations if these fall within the scope of the invention. The arrangement of the various elements and / or means and / or steps of the invention, in the embodiments described above, should not be understood as requiring such an arrangement in all implementations. In any event, it will be understood that various modifications may be made to these elements and / or means and / or steps without departing from the spirit and scope of the invention. In particular: the shape, dimensions and structural characteristics of voussoirs 1 of so that we can consider that these last 1 present a section transverse, oval, square or rectangular, the openings or orifices 4 worked into these voussoirs, they are also likely to vary in shape and dimensions from a circular opening to a par- shape particular, for example consisting of a section adapted to the dimensions and form of a very specific category of fish; the shape, dimensions and structural characteristics of the tympana 2, provided that these obstruct or close at least 80% of the lateral partition, the main function of which is to close off these two tympana. close / obstruct. The use of the verb "comporter", "comprendre" or "include" and its conjugated forms does not exclude the presence of other elements or steps than those stated in a claim. In claims, any reference sign in parentheses should not be interpreted as a limitation of the claim.

Claims

Demands

1. Underwater reef-forming structure system, intended to be installed Underwater, the system of structures forms a hollow enclosure extending longitudinally, the enclosure being formed by a plurality of voussoirs (1) defining a cover having openings (4) and presenting a section transverse in a semicircle or approximately in a semicircle, a plurality of longitudinal stringers (5) arranged on the ground (S) under in the form of two parallel bands, the lower ends of the voussoirs (1) being respectively mounted on at least one stringer (5), characterized in that the system comprises a plurality of tympana (2) arranged transversely to form a plurality of portions habitat (3) transversely partitioned along said enclosure.

2. Underwater structure system according to claim 1, wherein the tympana (2) are mounted on the stringers (5).

3. Underwater structure system according to claim 1 or 2, in which said system comprises a plurality of piles (8) driven into the ground, the said piles (8) being fixed to the stringers (5).

4. Underwater structure system according to any one of the claims previous indications, in which the voussoirs (1), advantageously also the aforementioned tympana (2), are made of fibre-reinforced concrete.

5. Underwater structure system according to any one of the claims previous indications, in which for at least two portions of habitat (3), the openings (4) of the voussoirs (1) of each of the two portions habitat (3) respectively have diameters or cross-sections openings (4) different from each other so as to be able to ac- to collect aquatic species of different sizes.

6. Underwater structure system according to any one of the claims previous indications, in which the tympanic membranes (2) present a thickness between ten and one hundred centimeters, preferably between forty and sixty centimeters.

7. Underwater structure system according to any one of the claims previous indications, in which the voussoirs (1) present a thickness between five and fifty centimeters, preferably between twenty and thirty centimeters.

8. Underwater structure system according to any one of the claims previous indications, in which said system further includes anti-scour mats (6) extending over the ground (S) from the longrines (5) outside the portions of habitat (3).

9. Underwater structure system according to any one of the claims previous indications, in which a section of the cover consists in two voussoirs (1) of identical dimensions and shape, the two voussoirs (1) being joined together to form the said section cover.

10. Underwater structure system according to any one of the claims previous indications, in which the height of said system in relation on the ground (S) is at most ten meters and the upper end of the voussoirs is positioned at a maximum of one meter from the water surface at its so-called average level.