GB2624702A

GB2624702A - A flood defence block

Info

Publication number: GB2624702A
Application number: GB2217819.8A
Authority: GB
Inventors: Dexter Stubbs Robert
Original assignee: Ecoshape Ltd
Current assignee: Ecoshape Ltd
Priority date: 2022-11-28
Filing date: 2022-11-28
Publication date: 2024-05-29
Also published as: DE202023107019U1; GB202217819D0

Abstract

A flood defence system having a number of interlocking blocks 1 having profiled ends 3, 5 engageable with complementary profiled ends of adjacent blocks, each block having a density greater than 950kg/m3, for stacking to form a temporary wall or barrier. The ends may have inter-engaging protruding convex 3 shapes and complementary recessed concave 5 shapes for allowing a pivoting articulated connection. Blocks may include a pair of central apertures or lumens 15 for receiving restraints, e.g. poles or rods, and top or bottom surfaces of stacked blocks may be configured to interlock with each other. The blocks may be made from recycled rubber and have a density greater than 1077kg per cubic meter. The blocks are of a size and density to allow them to be carried and rapidly stacked and interlocked to create a flood defence barrier, and dismantled for reuse after flooding. The rubber material minimises damage to a floor surface they are placed on. Blocks may include a reflective area 11 formed from embedded glass beads.

Description

A Flood Defence Block

Technical Field

The present application is in the field of flood defence barriers. This may be for containing a body of water to a confined area or for diverting flowing water away from houses, roads and places of business.

Background

Drainage systems can fail, pipes can burst and rivers can burst their banks. As a result, flooding can occur suddenly and from a number of different sources and locations-some not always the most accessible. Therefore, it is imperative that flood defence systems are quick and easy to implement so that an immediate or pre-empted response can be achieved when under time pressure.

Inversely, floods can recede and normal water levels can be reached as quickly as they were once breached. Therefore, it is important that flood defences can be dismantled and stored away easily and that they are able to only be deployed as and when needed. This balance of effective flood security and the resumption of normal day-to-day life is crucial to achieve.

Modular barriers such as sandbags and concrete blocks are commonly used to form a physical barrier between the flood water and the area to be protected and are known from the state of the art.

Both sandbags and concrete blocks are associated with technical and logistical issues. Sandbags are prone to spilling sediment in usage and may attract pests when stored for prolonged periods. Structures formed by stacking sandbags also lack uniformity and are therefore weaker than other alternatives. Said structures may also have gaps between sandbags and therefore can leak water into protected areas. Concrete blocks are large, heavy and hard. As a result, they are difficult to transport in bulk numbers and require more intensive labour to position at the required locations. These qualities can also cause the blocks to erode the ground when moved under the force of flood water as well as being difficult to store. Concrete blocks can therefore cause additional damage to road surfaces they are placed on during flood-type situations.

Aspects of the present invention are intended to address at least some of the above mentioned problems.

Statements of Invention

Aspects of the invention are set out in the independent claims. Optional features are set out in the dependent claims.

In accordance with a first aspect of the invention there is provided a flood defence block for protecting a location from the effects of water flow, the flood defence block comprising: a body with a proximal end and a distal end; wherein the proximal end of the block is configured to interlock with the distal end of a second block; wherein the distal end of the block is configured to interlock with a proximal end of a third block; wherein the body has a density of greater than 950 kg/m3. Advantageously, it has been found that flood defence blocks with a density over 950 kg/m3 have a far greater utility in prohibiting damage during flooding events. This is because they are less prone to motion in response to the flow of water, and so are more likely to stay positioned as intended, and to limit water ingress as intended.

Optionally, wherein the density is greater than 1000kg/m3. This has the advantage of further decreasing the risk of movement in response to flow of water and so provides a more secure placement. Blocks of this density can also therefore withstand greater flood forces.

Optionally wherein the density is greater than 1050kg/m3 and further optionally wherein the density is 1077kg/m3. These higher densities further decrease the likelihood of motion under the water force and therefore increase the forces the block can withstand before moving. It is noted that 1077kg/m3 is optimal in balancing minimising block movement and erosion of the ground.

Optionally, wherein the density is less than 1300kg/m3.

Optionally wherein the density is less than 1200kg/m3 and further optionally wherein the density is less than 1100kg/m3. Limiting the densities to the mentioned values prevents the block from eroding the ground should the block move under the water force.

Optionally, wherein the proximal end of the block is pivotable with respect to the distal end of the second block when the proximal end of the block and the distal end of the second block are interlocked; and/or the distal end of the block is pivotable with respect to the proximal end of the third block when the distal end of the block and the proximal end of the third block are interconnected. This advantageously allows the blocks to be placed in an adjustable shape that follows particular geometry, such as the curve of a road, or in a shape that can guide the flow of water to a particular favoured direction.

Optionally, wherein the distal end comprises a convex portion, and the proximal end comprises a concave portion. This may allow for optimal tessellation of blocks together.

Optionally, wherein the convex portion is a rounded protrusion, optionally forming a portion of a circle. Advantageously, this shape is more wear resistant as opposed to geometry involving vertices which is likely to be damaged during use, or storage.

Optionally, wherein the concave portion comprises a rounded recess, optionally the recess forming a portion of a circle. Advantageously, this is complementary in shape to the distal end and is appreciably more wear resistant than sharper non-rounded geometry.

Optionally, wherein the convex portion is equal in shape and size to the space formed by the concave portion. Such an arrangement allows for a compact male-female attachment means.

Optionally, wherein the body comprises a side face, and the side face comprises a reflective area. The reflective area being particularly advantageous in roadside deployment to identify the location of the hazardous areas and to alert road users to the presence of the flood defence blocks themselves.

Optionally, wherein the reflective area comprises a plurality of glass beads.

Advantageously, the bed of glass beads allows for reflection of light towards the viewer from any (or at the very least a large range of) incident angle. In comparison to a flat surface the spherical beads offer much more practical reflective use. According to the Law of Reflection, the angle of reflection is equal to the angle of incidence relative to a normal of that surface. Therefore, a flat surface would only reflect light away from a light source, e.g. a person in a car, unless it is positioned normal to it. This is not feasible to ensure in practice and so spherical glass beads are much more beneficial to increase probability of the light being reflected back towards a light source.

Optionally, wherein the glass beads are sat beneath a protective layer, for example a polyurethane layer. This very conveniently contains the glass beads and prevents them coming lose and detaching from the block.

Optionally, wherein the glass beads are sat on to a bedding layer configured such that the vertical extent of the glass beads is uniform, optionally wherein said bedding layer comprises a rubber conformance layer. Beneficially, the flat surface may allow for reflected light from bead one to form the incident light for bead two. This results in the reflection of light to a large range of angles from any incident angle. A flat finish may also be achieved.

Optionally, wherein the glass beads are adhered to the block, optionally by a pressure sensitive adhesive, further optionally wherein said pressure sensitive adhesive is positioned between the block and the bedding layer. A strong connection is therefore achieved without the need for fasteners. Such arrangement also has the advantage of being simple to manufacture and to implement.

Optionally, wherein the body comprises at least one central lumen, configured to allow a restraint to be accommodated therein, wherein the restraint is configured to keep the block at an intended position. This may reduce the amount of wear caused by the block on the road.

Optionally, the body comprises a second central lumen, wherein the first and second central lumens are aligned along a longitudinal centre line of the block. Advantageously, this allows the blocks to be stacked with more than one point of attachment, preventing any unwanted rotation relative to stacked blocks and therefore a much more uniform structure.

Optionally, wherein the block is configured to be stacked on top of a fourth block.

This may allow the vertical extent of a structure built from blocks to be adapted to the requirement based on the predicted extent of flood water.

Optionally, wherein the block comprises a base and a top portion, wherein the base of the block is configured to interlock with a top portion of a fourth block. Advantageously, this allows vertical structures to be formed without the need of external fastening means.

Optionally wherein the top portion of the block is configured to interlock with a base of a fifth block. This advantageously allows structures to be formed with no height limitations and so can provide effective flood defence when water levels are high. The structure height can also be adjusted to suit water levels.

Optionally, wherein the block is 60cm long, 30cm wide and 10cm high. Advantageously, these dimensions are at a scale that is convenient enough to carry by a single person in a single hand. Many blocks can also be stacked since they are thin enough and carried using both arms since the 60cm is well within a normal persons arm span. The width of the blocks is also convenient for such action.

Optionally, wherein the reflective area is 10cm long and 3cm high, and is centrally located on the side of the block. Advantageously, this size of reflector is large enough to allow a person to see the block from a substantial distance away. This size is also small enough to be a cost effective solution to achieving reflecting means.

Optionally, wherein the radius of the concave portion, and the radius of the distal portion is 15cm. This size allows for an easy attachment procedure as the tolerance of fit are high.

Brief Description of Finures

Figure 1 is a perspective view of a flood defence block in a first embodiment seen from the distal end.

Figure 2 is a perspective view of the flood defence block of Figure 1 seen from the proximal end.

Figure 3a is a side-on view of the flood defence block of Figures 1 and 2 with optional measurements.

Figure 3b is a frontal view of the flood defence block of Figures 1 and 2 with optional measurements.

Figure 3c birds-eye view of the flood defence block of Figures 1 and 2 with optional measurements.

Figure 4 shows a perspective view of an articulated structure formed by the flood defence blocks of Figures 1-3.

Figure 5 is a perspective view of three articulated structures of Figure 4 in a stacked formation.

Figure 6 is a zoomed in, part-cross sectioned perspective view of an exemplary reflective substrate that may be used in conjunction with the flood defence block of Figures 1-3.

Detailed Description

Figures 1 and 2 show a flood defence block for protecting a location from the effects of water flow, the flood defence block comprising: a body with a proximal end and a distal end; wherein the proximal end of the block is configured to interlock with the distal end of a second block; wherein the distal end of the block is configured to interlock with a proximal end of a third block; wherein the body has a density of greater than 950 kg/m3.

The flood defence block 1, as shown in Figures 1 and 2, is a three dimensional structure defined by straight parallel lateral edges and rounded parallel longitudinal ends. Dimensionally, flood defence block 1 is considerably greater in length and width than it is in height and is approximately and optionally twice its width in length.

At its distal end, the flood defence block 1 comprises a convex portion 3 that is configured to act as a male attachment means. The convex portion 3 may occupy the entire width of the distal end, as shown, or it may optionally occupy only part of this width. In the embodiment shown, the convex portion 3 is a rounded protrusion formed by an arc of radius equivalent to that of half the width of the flood defence block 1. In a separate embodiment, the convex portion 3 could be replaced with a triangular portion or other protruding shape. However, the convex shape implemented in the current embodiment brings forth anti-wear and anti-chipping benefits courtesy of its rounded and circular geometry.

Also shown in Figure 1, and more clearly in Figure 2, is a concave rounded recess at the proximal end of the flood defence block 1. The concave portion 5 is complementary in shape and size to the convex portion 3. Alternatively, it can be described that the convex portion 3 is equal in shape and size to the space formed by the concave portion 5 and the latter is therefore configured to act as the female attachment means. In the current embodiment, the recess forms a portion of a circle mimicking the circular shape of the distal end. However, for alternative embodiments it is entirely possible to deviate from the shape shown as long as a complementary fit is achieved with the distal end. It is worthy of note that the parallel relationship of the distal and proximal ends allows for important uniformity and symmetry that leads to convenience in stacking and storing the blocks as well as manufacturing them. The vertices of the concave portion 5 may be rounded for anti-wear purposes.

Figures 1 and 2 show side faces 7 providing a surface for the reflective area 11. The reflective area 11 is of sufficient height and longitudinal length to define a noticeably large reflecting surface that can be seen from a significant distance away. The reflective area 11 of this embodiment is not of any substantial thickness that would require a cavity in the side face 7 however a slot 13 can be optionally utilised to better define the reflective area, as shown. Slot 13 protrudes from the top portion 9 to a distance roughly half that of the thickness of flood defence block 1. The slot 13 does not protrude any substantial distance transversely into flood defence block 1.

The flood defence block 1 further comprises the central lumens 15. Figures 1 and 2 show an embodiment with two central lumens 15 that are aligned and separated along a longitudinal centre line of the flood defence block 1. It is, however, entirely possible that only one central lumen 15 be utilised in another embodiment. Such an arrangement is an optional variation to the embodiment shown and falls within the same inventive concept. Each lumen 15 is a through hole configured to allow a restraint to be accommodated within and so forms a clear passage from the top portion 9 to the base portion of flood defence block 1. Such a restraint may directly contact the surface beneath the flood defence block, such as a road surface.

The aforementioned restraint can be any means configured to keep the flood defence block 1 at an intended location. It can also be a means to form a connection between layers of stacked blocks as will be described later. For such an arrangement, it is a great advantage to have two central lumens 15 as this allows the blocks to be stacked with more than one point of attachment to one another. Therefore, preventing any unwanted rotation relative to stacked blocks and thus forming a much more uniform structure. A plurality of central lumens 15 would also directly provide a more robustly anchored structure to either the ground or to other blocks in a stacked formation.

Another important aspect of the flood defence block 1 shown in Figures 1 and 2 is its density. The density of flood defence block 1 is designed to be greater than 950 kg/m3. Blocks of such densities have far greater utility in prohibiting damage during flooding events. This is because they are less prone to motion in response to the flow of water, and so are more likely to stay positioned as intended, and to limit water ingress as intended. These benefits can be emphasised with blocks of density greater than 1000kg/m3, for example, blocks of density 1050kg/m3 and 1077kg/m3. In development of the present flood defence block an increased density (to the value specified above) was found to be highly advantageous, especially in the case of high velocity flood water, such as surface runoff on road surfaces. Such high velocity water may move less dense material, and so this increased density is particularly useful in some embodiments. This density is particularly advantageous in combination with the blocks being made from a rubberised material such as rubber or plastic. Rubber may be particularly advantageous, and recycled rubber, recycled rubber granulate, or virgin rubber may be used. This material is capable of such increased densities, but is not liable to cause erosion of road surfaces.

There is however an upper limit to the density the flood defence block 1 can have in some embodiments. To prevent the flood defence block 1 from eroding the ground, its density is preferably less than 1300kg/m3. Alternative embodiments may cap the density values to less than 1200kg/m3 or 1100kg/m3 to ensure minimal ground erosion (for instance for use on ground that is particularly prone or valuable, such as the surface of automobile racing circuits). It is noted that 1077kg/m3 is optimal in balancing minimal block movement and erosion of the ground. This density value for the block is therefore highly advantageous in balancing these two conflicting requirements of the block. Other embodiments (for example for use on surfaces where erosion is not a concern) may not have a maximum density.

Particularly useful ranges for the density include 950 kg/m3 to 1300 kg/m3, 1000 kg/m3 to 1200 kg/m3, and 1050 kg/m3 to 1100 kg/m3. These ranges may depend on the severity of the water flow, the nature of the ground surface, and its propensity to erode. For example, for a ground surface here erosion is less of a concern, and there is a low water flow expected the first range may be sufficient. For ground surface prone to erosion, and where high water flow is expected the narrowest range may be of most use. The second range is more of an intermediate value and may be suitable for most applications.

It is noted that there may be some embodiments in which the density is outside of the ranges detailed above.

Figures 3 a, b and c display the dimensions of the various features of a first embodiment of the flood defence block 1 mentioned thus far. The dimensions can be largely modified for other embodiments. However, it is of note the displayed dimensions are at a scale that is convenient to carry by a person in one hand. These dimensions are also ergonomic for carrying multiple blocks stacked up vertically.

The 60cm length, as seen in Figure 3c, is well within the arm span for most persons and ensures a controlled grip. Assuming a person is carrying the blocks at a comfortable navel height, the 10.5cm thickness of each block, highlighted in Figure 3b, allows for a number of blocks to be stacked up until the chin. Stacking up to chin height will ensure unobstructed vision of the person carrying the blocks and also would allow the chin to be used as a support/balancing means when resting on the top block of the stack. The 30 cm width of the blocks is also convenient for safe transport technique as the centre of mass of the stack of blocks is never acting too far in front of the body of the person carrying the blocks.

Other dimensions outlined in Figure 3c are of the central lumens 15 and the reflective area 11 in Figure 3a. The longitudinal distance between the two central lumens 15 is substantial enough such that when stacked with a restraining means, the rotation between top and bottom blocks can be restricted. This gives a much more uniform and therefore stable structure. Optionally, the dimensions of the reflective area are 10cm in length and 3cm in height. As mentioned this is of sufficient size to ensure visibility from afar yet being cost effective by not being excessive in size.

Figure 3c also shows that the radius of the distal portion is 15cm. This size allows for an easy attachment procedure as the tolerance of fit at this scale are high.

Figure 4 shows an articulated structure formed by five flood defence blocks 1 as described above, with each flood defence block 1 forming a module of the articulated structure. The distal end of a first block is seen to interlock with a proximal end of a second block. The interlocking made possible through convex portion 3 of block 1 snug-fitting within the space formed by the recess of the concave portion 5 of a second block. This connection is repeated for the three remaining blocks in Figure 4.

A key feature of the described connection is that there is pivotal motion between two blocks in the transverse direction. This is courtesy of the circular geometry involved in the interlocking. The distal end of a first block has clearance to yaw (pivot transversely) within the recess of a proximal end of a second block. This freedom to yaw allows for the two interlocked blocks to be angularly separated yet maintain flush contact along most of the surface area of the convex 3 and concave portions 5. This contact maintains the structure's impermeability to flood water. Although this pivotal motion is limited to a narrow range of angles for each connection point, it still allows for sufficient manipulation of the articulated structure through the combined effects of many connection points. The linear structure shown in Figure 4 can therefore be adjusted to yield a structure that curves in the transverse direction. This is particularly beneficial when trying to guide water to or away from a particular location by providing a barrier pathway that utilises the flow current. It must also be highlighted that since there is no obstruction on the top and bottom edges of the connection faces, there is vertical flexibility to accommodate the profile of hilly and bumpy terrain.

Figure 5 shows the three articulated structures of Figure 4 in a stacked formation. A first flood defence block 1 is configured to be stacked on top of a second flood defence block 200. Similarly, a third flood defence block 300 is configured to be to stacked on top of a first flood defence block. This is made possible by each block possessing a flat base portion 17, flat top portion 9 and uniformly positioned central lumens 15.

Once blocks are positioned on top of one another, the flat base and top portions allow for flush contact whilst the central lumens 15 align to provide an unobstructed circular cavity through both the blocks. This through hole is configured to house a restraining means (not shown), preferably of rod-like nature. The restraining means is configured to interlock the longitudinal and transverse motion of the stacked blocks to one another. A plurality of central lumens 15 will also restrain the rotational motion of the blocks preventing any unwanted rotation relative to stacked blocks and therefore form a much more uniform structure. In some embodiments restraining means may not be needed, and friction, or other attachment means, may be sufficient to adhere the blocks together.

The uniformity and symmetry of flood defence block 1 ensures that structures can be stacked with no height limitations. There is no design limitation that caps the height of stacked structures since each module is identical and so the same connection can be repeated block after block. The blocks can be stacked to form very tall structures and so can provide effective flood defence when water levels are high. The width of 30cm ensures a relatively low centre of mass and this means that the stacked structures are very stable. The restraining means through the central lumen 15 can also be used as a stability enhancing feature, much-like reinforcements in other mechanical structures.

Figure 6 shows a perspective view of an exemplary reflective substrate 19 that may be used in conjunction with the flood defence block 1 to act as the reflective area 11. The substrate 19 comprises a bedding layer 21 upon which a plurality of glass beads 23 are part submerged. In the embodiment shown, this bedding layer 21 is comprised of a rubber conformance layer with the vertical extent of the glass beads 23 being uniform. The rubberised nature of the bedding layer 21 conveniently accommodates the glass beads 23 by simply allowing the pressing of the beads 23 into the bed 21. This requires minimal preparation of the rubber bed 21 to achieve the flat finish (uniform vertical protrusion). Had the bedding layer 21 been made of a harder (non-rubberised) substance, a cavity would need to be defined for each glass bead 23 prior to fitting. Such embodiments although possible, require greater manufacturing and assembling efforts than the one shown in Figure 6.

The bedding layer 21 (with the glass beads 23 dispersed within) attaches onto side faces 7 of the flood defence block 1 via an adhesive 25. Such adhesive can be a pressure sensitive adhesive applied between the side face 7 and the bedding layer 21. Therefore, a strong connection can be achieved without the need for external or additional fasteners. Such arrangement also has the advantage of being simple to manufacture and to implement with minimal user skill. There is also an advantage to the adhesive being waterproof to prevent dislodgment of the reflective area 11 in use by flood water.

The implementation of glass beads 23 over other mediums allows for the reflection of light towards the viewer from any incident angle. The spherical nature of the beads 23 reflect incident light through to multiple angles. This increases the probability of the reflected light being directed towards the user. Should a none spherical or flat means be utilised, the Law of Reflection dictates that the light will be reflected away from the incident source unless, of course, the surface is normal to the incident light. It is not feasible to ensure this orthogonality between reflecting surface and the incident source in practical use. Therefore, the spherical beads offer a much more convenient solution to reflect light in a road and urban setting by reflecting light through a large range of angles in all directions. Hence, the probability of the reflected light entering the eyes of a person standing proximal to a light source is increased. Having the beads 23 configured such that their vertical extent is uniform aids this function as the reflected light from bead one forms the incident light for another bead and so on and henceforth for the remaining beads. This means that each reflected light ray is reflected multiple times resulting in the increased range of angular reflection that is so beneficial.

A protective layer (not shown), optionally a polyurethane layer, covers the glass beads so that they are fixed to the bedding layer 21. Such a layer contains the glass beads 23 to the bedding layer 21 and prevents them detaching without compromising the transparency and reflectiveness of the glass beads 23.

The above embodiments are to be understood as illustrative examples. Further embodiments are also envisaged. It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments.

Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.

Claims

Claims 1. A flood defence block for protecting a location from the effects of water flow, the flood defence block comprising: a body with a proximal end and a distal end; wherein the proximal end of the block is configured to interlock with the distal end of a second block; wherein the distal end of the block is configured to interlock with a proximal end of a third block; wherein the body has a density of greater than 950kg/m3.
2. The flood defence block of claim 1, wherein the density is greater than 1000kg/m3, optionally wherein the density is greater than 1050kg/m3 and further optionally wherein the density is 1077kg/m3.
3. The flood defence block of claims 1 or 2, wherein the density is less than 1300kg/m3, optionally wherein the density is less than 1200kg/m3, further optionally wherein the density is less than 1100kg/m3.
4. The flood defence block of any preceding claim, wherein the proximal end of the block is pivotable with respect to the distal end of the second block when the proximal end of the block and the distal end of the second block are interlocked; and/or the distal end of the block is pivotable with respect to the proximal end of the third block when the distal end of the block and the proximal end of the third block are interconnected.
5. The flood defence block of claims any preceding claim, wherein the distal end comprises a convex portion, and the proximal end comprises a concave portion.
6. The flood defence block of claim 5, wherein the convex portion is a rounded protrusion, optionally forming a portion of a circle.
7. The flood defence block of claims 5 or 6, wherein the concave portion comprises a rounded recess, optionally the recess forming a portion of a circle.
8. The flood defence block of any of claims 5-7, wherein the convex portion is equal in shape and size to the space formed by the concave portion.
9. The flood defence block of any preceding claim, wherein the body comprises a side face, and the side face comprises a reflective area.
10. The flood defence block of claim 9, wherein the reflective area comprises a plurality of glass beads.
11. The flood defence block of claim 10, wherein the glass beads are sat beneath a protective layer, for example a polyurethane layer.
12. The flood defence block of claims 10 or 11, wherein the glass beads are sat on to a bedding layer configured such that the vertical extent of the glass beads is uniform, optionally wherein said bedding layer comprises a rubber conformance layer.
13. The flood defence block of any of claims 10-12, wherein the glass beads are adhered to the block, optionally by a pressure sensitive adhesive, further optionally wherein said pressure sensitive adhesive is positioned between the block and the bedding layer.
14. The flood defence block of any preceding claim, wherein the body comprises at least one central lumen, configured to allow a restraint to be accommodated therein, wherein the restraint is configured to keep the block at an intended position.
15. The flood defence block of claim 14, comprising a second central lumen, wherein the first and second central lumens are aligned along a longitudinal centre line of the block.
16. The flood defence block of any preceding claim, wherein the block is configured to be stacked on top of a fourth block.
17. The flood defence block of claim 16, wherein the block comprises a base and a top portion, wherein the base of the block is configured to interlock with a top portion of a fourth block.
18. The flood defence block of claim 16 or 17, wherein the top portion of the block is configured to interlock with a base of a fifth block.
19. The flood defence block of any preceding claim, wherein the block is 60cm long, 30cm wide and 10cm high.
20. The flood defence block of claim 19, wherein the reflective area is 10cm long and 3cm high, and is centrally located on the side of the block.
21. The flood defence block of any preceding claim, wherein the radius of the concave portion, and the radius of the distal portion is 15cm.
22. The flood defence block of any preceding claim, wherein the body is formed from rubber, or a rubberised compound.