FIELD OF INVENTION

The present invention relates to an artificial reef. In particular, the invention relates to an artificial reef that is configured to generate waves for recreational purposes, such as surfing. BACKGROUND ART

A surf break is a permanent or semi-permanent obstruction, such as a coral reef, rock, shoal, or headland that causes a wave to break, forming a barrelling wave or other wave that can be surfed, before it eventually collapses. The topography of the seabed determines the shape of the wave and type of break. Since shoals can change size and location, affecting the break, it takes commitment and skill to find good breaks. Some surf breaks are quite dangerous, since the surfer can collide with a reef or rocks below the water. There are numerous types of surf breaks. These are defined as permanent or semi-permanent obstructions that causes a wave to break, rather than by the nature of the wave itself. Artificial wave pools are an example of technology changing what is considered a 'surf break' or 'surfable wave'. Some 'surf break' locations may be partly or wholly formed and influenced by human activities. These effects are variable and may be either negative or positive with respect to the effect on local surf quality. Some types of surf breaks will be discussed below to provide background information only.

A point break refers to the place where waves hit a point of land or rocks jutting out from the coastline. Bells Beach in Australia and Jardim do Mar in Madeira, Portugal are examples of point breaks. They can break either left or right, and in rare cases form a central peak which breaks both ways around a central headland (e.g. Punta Rocas in Peru). The sea floor in such locations can consist of rocks, sand, or coral.

A beach break takes place where waves break on a usually sandy seabed. An example of a classic beach break is Hossegor in Southern France, which is famous for waves of up to 6m (20ft). Sometimes 'beaches' can contain little or no sand, and the 'beach' may consist of rocks or boulders and pebbles. A 'boulder beach' is an example.

A reef break occurs when a wave breaks over a coral reef or a rocky seabed. Examples are Cloudbreak in Fiji and Jaws in Maui. A reef break may occur close to the shore, or well offshore from the shoreline, breaking in the open ocean and petering out before the wave reaches the shore. Examples include Queenscliff Bommie in Australia and Dungeons in South Africa. In Australia, waves produced on these open ocean reefs are sometimes called Bombora or 'Bommie' waves, after the aboriginal word for offshore reef, 'bombora'. Sometimes reefs which occur in the open ocean, but which do not breach the surface are called 'Banks'. The Cortes Bank off California is an example. There are also examples of man- made reefs specifically designed and made for surfing. Some artificial harbours also create new reef break waves. Examples include Newcastle Harbour in Australia. Shipwreck breaks usually form from sand build up over submerged or partly submerged shipwrecks. They may be either temporary or more or less permanent, depending on whether the wreck remains in place for a significant period. Examples occur at The Wreck, Byron Bay, New South Wales, and at Stockton Beach, Newcastle, New South Wales. A shore break is a wave that breaks directly on, or very close to the shore. This happens when the beach is very steep at the shoreline. These waves are essentially just a form of beach or reef break, but breaking very close to the shore.

The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practice.

SUMMARY OF INVENTION

As mentioned above, the present invention relates generally to an artificial reef. In particular, the invention relates to an artificial reef that is configured to generate waves for recreational purposes, such as surfing.

According to one aspect of the invention there is provided an artificial reef comprising:

a first reef section and a second reef section associated with the first reef section, the first reef section and the second reef section diverging from one another from a forward section;

at least one ballast tank associated with each of the first reef section and the second reef section and adapted to adjust buoyancy of the artificial reef; and a mooring associated with the forward section, wherein the mooring is configured to permit movement of the first reef section and second reef section in response to tidal variation and translation of the first reef section and second reef section in response to swell directional variation.

The first reef section and second reef section may take any suitable form. For example, it is envisaged that the first and second reef sections may independently comprise elongate arcuate sections, or may comprise sections that substantially form a semicircular, circular or elliptical artificial reef. However, in a preferred embodiment, the first reef section and second reef section comprise elongate divergent sections that form a substantially V-shaped artificial reef.

The first reef section and second reef section may be integral with each other, or may be fixedly secured to one another. That is, the relationship between the first and second reef sections may be fixed. In a preferred embodiment, the first reef section and second reef section are hingedly connected at the forward section.

According to this embodiment, the first reef section and second reef section preferably comprise a locking mechanism to lock the first reef section and second reef section in a position relative to one another. For example, the first reef section and second reef section may be configured to be lockable in a closed orientation in which the first reef section and second reef section are substantially parallel to one another, a wave generating orientation in which the first reef section and second reef section diverge from one another at an angle of about 45°, and an extended orientation in which the first reef section and second reef section diverge from one another at an angle of above 90°.

In order to ameliorate or eliminate rolling and pitching of the artificial reef, it is preferred that the first reef section and second reef section be of a length greater than about 2.5 wave lengths of the largest swell expected at a given location. For example, the first reef section and second reef section may be of a length of from 300 to 500 metres.

The profile of the first and second reef sections may take any suitable form. In certain embodiments, the first reef section and second reef section have a cross- sectional profile comprising a first incline portion, a trough portion extending from the first incline portion, and a second incline portion extending from the trough portion. The incline portions and trough may include linear profiles or curved profiles.

The artificial reef according to the invention includes ballast tanks associated with the first reef section and the second reef section and adapted to adjust buoyancy of the artificial reef. Advantageously, this facilitates control of the depth at which the artificial reef is maintained. This may also facilitate flooding of the ballast tanks and sinking of the artificial reef to the sea floor in undesirable conditions, thereby protecting the artificial reef from damage. In certain embodiments, the ballast tanks extend along the length of the first reef section and the second reef section, although they may also be disposed at locations along the length of the first reef section and the second reef section.

In certain embodiments, the artificial reef further comprising one or more pumps associated with the ballast tanks and configured to pump water into and out of the ballast tanks. As noted above, this advantageously facilitates control over the depth of the artificial reef. For example, in certain situations it may be desirable to have the artificial reef 75% submerged and 25% above the water level. As previously described, during unfavourable conditions it may be desirable to sink the artificial reef to the sea floor to prevent damage to the artificial reef. In certain embodiments, the first reef section and the second reef section may comprise stabilising elements on undersides thereof configured to be embedded in the sea floor, for example, when the ballast tanks are flooded to sink the artificial reef to the sea floor. The stabilising elements may comprise elongate arcuate fins extending from the undersides of the first reef section and the second reef section. The stabilising elements may also or additionally comprise elongate ridges extending from longitudinal edges of the undersides of the first reef section and the second reef section. The artificial reef may further comprise water jets associated with the first reef section and the second reef section configured to assist embedding of the stabilising elements in the sea floor and removal of the stabilising elements from the sea floor. For example, when an operator wishes to raise the artificial reef from the sea floor, water can be pumped from the ballast tanks to increase buoyancy of the artificial reef and sand removed from the stabilising elements with the water jets, allowing the artificial reef to float upward to the surface of the water. It is also envisaged that when the artificial reef is secured to the sea floor, it may advantageously prevent or alleviate damage to the coast by resisting wave action on the coast.

The mooring may take any suitable form. For example, in rudimentary forms the mooring may comprise a mooring line attached to the forward section of the artificial reef and anchored to the sea floor, or may comprise a mooring line attached to the forward section of the artificial reef at one end thereof and to a monopile secured to a sea floor foundation at the other end thereof. In certain embodiments, the mooring comprises a mooring aperture disposed in the forward section of the artificial reef and a monopile secured to a sea floor foundation and extending through the mooring aperture, the mooring aperture being configured to facilitate vertical and rotational movement of the monopile within the aperture.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS To further clarify various aspects of some embodiments of the present invention, a more particular description of the invention will be rendered by references to specific embodiments thereof, which are illustrated in the appended drawings. It should be appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting on its scope. The invention will be described and explained with additional specificity and detail through the accompanying drawings in which: FIG. 1 illustrates a side view of an artificial reef in situ according an embodiment of the invention. FIG. 2 illustrates a plan view of the artificial reef of Figure 1 in situ.

FIG. 3 illustrates a plan view of the artificial reef of Figure 1 in situ under a change of swell direction. FIG. 4 illustrates plan views of artificial reefs according to alternative embodiments of the invention.

FIG. 5A illustrates a perspective view of an artificial reef according to an embodiment of the invention.

FIG. 5B illustrates the side profile of the artificial reef of Figure 5A.

FIG. 6A illustrates a perspective view of an artificial reef according to an embodiment of the invention.

FIG. 6B illustrates the side profile of the artificial reef of Figure 6A.

FIG. 7 illustrates a plan view of an artificial reef according to an embodiment of the invention.

FIG. 8 illustrates a front perspective view of the artificial reef of Figure 7.

FIG. 9 illustrates a side perspective view of the artificial reef of Figure 7. FIG. 10 illustrates a cut away end section of a reef section according to an embodiment of the invention.

FIG. 1 1 illustrates a cut away end section of a reef section according to another embodiment of the invention.

FIG. 12 illustrates a side view of a hinged connection between first and second reef sections according to an embodiment of the invention. FIG. 13 illustrates an underside end view of the hinged connection of Figure 12.

FIG. 14 illustrates a perspective underside end view of the hinged connection of Figure 12 and first and second reef sections. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, this specification will describe the present invention according to the preferred embodiments. It is to be understood that limiting the description to the preferred embodiments of the invention is merely to facilitate discussion of the present invention and it is envisioned without departing from the scope of the appended claims.

Referring to Figures 1 to 3, an artificial reef 100 is illustrated. The artificial reef 100 includes a first reef section 102 and a second reef section 104 associated with the first reef section102. As illustrated, the first reef section 102 and the second reef section 104 diverge from one another from a forward section 106 to form a wedge or V-shaped artificial reef 100. As illustrated in Figure 1 , the artificial reef 100 is a floating reef which is approximately 75% submerged and 25% above the water level. The artificial reef 100 includes a mooring 108 associated with the forward section 106. In this embodiment, the mooring 108 includes a mooring line 1 10 attached to the forward section 106 of the artificial reef 100 at one end thereof and to a monopile 1 12 secured to a sea floor foundation at the other end thereof. The mooring 108 permits movement of the first reef section 102 and second reef section 104 not only in response to tidal variation, but also in response to translation of the first reef section 102 and second reef section 104 due to swell directional variation (g), as illustrated in Figure 3. In alternative embodiments, as illustrated in Figure 4, the mooring comprises a mooring aperture (illustrated in Figures 7 to 9) disposed in the forward section 106 of the artificial reef 100 and a monopile 412 secured to a sea floor foundation and extending through the mooring aperture. In this embodiment, the mooring aperture is configured to facilitate vertical and rotational movement of the monopile 412 within the aperture.

Referring to Figures 5A and 5B, a simplified illustration of a profile of the artificial reef 500 is provided. As illustrated, the first reef section 502 and second reef section 504 have a cross-sectional profile comprising a first incline portion 506, a trough portion 508 extending from the first incline portion 506, and a second incline portion 510 extending from the trough portion 508. As illustrated, the incline portions 506, 510 and trough 508 have linear profiles. As illustrated in Figures 6A and 6B, the incline portions 606, 610 and trough 608 have curved profiles.

A further illustration of an artificial reef 700 is provided in Figures 7 to 9. The first reef section 702 and second reef section 704 in this embodiment are secured to one another in a fixed relationship. A mooring aperture 710 is provide in a forward section 706 of the artificial reef 700. Turning to Figures 10 and 14, the artificial reef 1000 includes ballast tanks 1010 associated with the first reef section 1002 and the second reef section 1004. As illustrate, the ballast tanks 1010 comprise voids that extend along the length of the first reef section 1002 and the second reef section 1004, although they may also be disposed at locations along the length of the first reef section 1002 and the second reef section 1004. Water may be pumped into these voids to adjust the buoyancy of the artificial reef 1000, facilitating the control of the depth at which the artificial reef 1000 is maintained. The ballast tanks 1010, or voids, may be flooded to effect sinking of the artificial reef 1000 to the sea floor in undesirable conditions, thereby protecting the artificial reef 1000 from damage.

As illustrated in Figures 10 and 14, the first reef section 1002 and the second reef section 1004 include stabilising elements in the form of elongate arcuate fins 1012 extending from the undersides of the first reef section 1002 and the second reef section 1004. Elongate ridges 1014 extending from longitudinal edges of the undersides of the first reef section 1002 and the second reef section 1004 are also provided.

The first reef section 1002 and second reef section 1004 are hingedly connected at a forward section 1006 by a hinge 1016. According to this embodiment, the first reef section 1002 and second reef section 1004 comprise a locking mechanism (not shown) to lock the first reef section 1002 and second reef section 1004 in a position relative to one another. Specifically, in a closed orientation in which the first reef section 1002 and second reef section 1004 are substantially parallel to one another, a wave generating orientation in which the first reef section 1002 and second reef section 1004 diverge from one another at an angle of about 45°, and an extended orientation in which the first reef section 1002 and second reef section 1004 diverge from one another at an angle of above 90°. Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as“comprises” or“comprising”, will be understood to imply the inclusion of a stated step or element or integer or group of steps or elements or integers, but not the exclusion of any other step or element or integer or group of steps, elements or integers. Thus, in the context of this specification, the term“comprising” is used in an inclusive sense and thus should be understood as meaning“including principally, but not necessarily solely”.

Unless the context requires otherwise or specifically stated to the contrary, integers, steps or elements of the invention recited herein as singular integers, steps or elements clearly encompass both singular and plural forms of the recited integers, steps or elements.

It will be appreciated that the foregoing description has been given by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons of skill in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.