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Title:
A BLOCK AND A SYSTEM FOR USE IN BUILDING A STRUCTURE
Document Type and Number:
WIPO Patent Application WO/2008/037022
Kind Code:
A1
Abstract:
A block for use in building a structure, the block comprising a body and at least one cavity extending through the body, the body having two side walls and at least one open end, the block also comprising at least one laterally extending wall extending between the two side walls and defining one end of the cavity, the at least one laterally extending wall having an aperture formed therein for enabling the passage of grout or any other core filling material from the at least one cavity to the at least one open end of the body when building the structure, wherein, inner corners of end edges of the side walls at the at least one open end of the block are chamfered, the chamfered end edges for forming a void between each of the side walls and the side walls of another block laid end to end with the block to enable grout or any other core filling material to be provided close to the outer faces of the block.

Inventors:
COLEFAX, Warwick, Ian (1/20 Wilmette Place, Mona Vale, NSW 2103, AU)
COLEFAX, Robert, Foster (1/20 Wilmette Place, Mona Vale, NSW 2103, AU)
Application Number:
AU2007/001444
Publication Date:
April 03, 2008
Filing Date:
September 28, 2007
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
BUILDING INNOVATIONS PTY LTD (1/20 Wilmette Place, Mona Vale, NSW 2103, AU)
COLEFAX, Warwick, Ian (1/20 Wilmette Place, Mona Vale, NSW 2103, AU)
COLEFAX, Robert, Foster (1/20 Wilmette Place, Mona Vale, NSW 2103, AU)
International Classes:
E04B1/04; E04B1/41; E04C1/00; F16B1/00
Foreign References:
DE10103080A1
DE2361029A1
FR2681359A1
AU2004237894A1
US5351457A
US20030221386A1
AU2048792A
US6010279A
Attorney, Agent or Firm:
GRIFFITH HACK (Level 10, 167 Eagle StreetBrisbane, QLD 4000, AU)
Download PDF:
Claims:

CLAIMS :

1. A block for use in building a structure, the block comprising a body and at least one cavity extending 5 through the body, the body having two side walls and at least one open end, the block also comprising at least one laterally extending wall extending between the two side walls and defining one end of the cavity, the at least one laterally extending wall having an aperture formed therein 0 for enabling the passage of grout or any other core filling material from the at least one cavity to the at least one open end of the body when building the structure, wherein, inner corners of end edges of the side walls at the at least one open end of the block are 5 chamfered, the chamfered end edges for forming a void , between each of the side walls and the side walls of another block laid end to end with the block to enable grout or any other core filling material to be provided close to the outer faces of the block. 0

2. A block as claimed in claim 1, wherein the block also comprises at least one pair of opposing chamfered projections, projecting from the side walls of the body, and located towards the at least one open end of the 5 block.

3. A block as claimed in claim 2, wherein the chamfers of the chamfered projections face outwardly from the open end of the block and are located on the innermost 0 corner of each of the projections.

4. A block as claimed in any one of the preceding claims, wherein, innermost corners of top edges of the side walls are chamfered, the chamfered top edges for 5 forming a void between each of the side walls and the side walls of another block laid on top. of the block.

5. A block as claimed in any one of the preceding claims, wherein, the block also comprises opposing flanges extending from the side walls and located towards the bottom of the block.

6. A block as claimed in claim 5, wherein the opposing flanges are of increasing thickness towards the bottom of the block.

7. A block as claimed in any one of the preceding claims, wherein, the aperture of the at least one laterally extending wall is centrally located within the laterally extending wall.

8. A block as claimed in any one of the preceding claims, wherein, the aperture is a substantially V-shaped recess formed in the top of the laterally extending wall.

9. A block as claimed in any one of the preceding claims, wherein, the depth of the aperture at its lowest point is 25 to 50% of the height of the block.

10. A block as claimed in any one of claims 1 to 8, wherein the depth of the aperture at its lowest point is approximately 40% of the height of the block.

11. A block as claimed in any one of the preceding claims, wherein the block also comprises opposing pairs of grooves formed in the side walls to enable the portion of the block between a pair of the grooves to be readily knocked out of one or both side walls.

12. A block as claimed in claim 11, wherein the block also comprises dimples on the top edges of the side walls in line with and corresponding to each of the grooves to enable connectors to connect the block to the open end of another block laid at right angles to the block.

13. A connector for connecting blocks together, the connector comprising an approximately rectangular base portion and four legs located at and extending from each corner of the base portion, the legs for engaging portions of the blocks.

14. A connector as claimed in claim 13, wherein the base portion comprises four sloping walls arranged in a rectangle and angled inwardly.

15. A connector as claimed in either claim 13 or 14, wherein, the connector also comprises end plates at opposing ends of the connector, each end plate comprising a pair of members joined by a web.

16. A connector as claimed in claim 15, wherein the members of the end plates are each connected at right angles to one of the legs, forming right angled posts.

17. A connector as claimed in either claim 15 or 16, wherein, the web of each end plate has a groove formed therein for receiving and locating a horizontal reinforcing rod, which may pass through the connector when building a structure using blocks and the connector.

18. A connector as claimed in any one of claims 15 to

17, wherein the connector also comprises tabs extending approximately perpendicularly between the inner face of each member and the outer face of each leg.

19. A connector as claimed in any one of claims 15 to

18, wherein the members are shaped with a taper towards the members at opposing ends to enable the members to have a clearance from portions of the blocks which the connector is connecting when the connector is initially

inserted, but gain a tighter fit with the portions of the blocks as the connector is pushed down to its at-rest position.

20. A connector as claimed in any of claims 13 to 19, wherein, the legs are shaped with a taper away from the legs on oppoeing sides to enable the legs to have a clearance from portions of the blocks which the connector is connecting when the connector is initially inserted, but gain a tighter fit with the portions of the blocks as the connector is pushed down to its at-rest position.

21. A connector as claimed in any one of claims 13 to 20, wherein the connector comprises substantial spaces between the legs to enable the passage of grout or any other core filling material through the connector.

22. A connector as claimed in any one of claims 13 to

22. wherein the connector is manufactured of a resilient material, such as polypropylene or polyvinylchloride (PVC) for example.

23. A system for use in building a structure, the system comprising a plurality of blocks as claimed in any one of claims 1 to 12 and at least one connector for connecting blocks together.

24. A system as claimed in claim 23, wherein the system comprises a plurality of connectors.

25. A system as claimed in either claim 23 or 24, wherein the connector (s) is a connector (s) as claimed in any of claims 13 to 22.

26. A system as claimed in any one of claims 23 to 25, wherein, the βystem also comprises at least one biscuit for filling a space in the structure for which

none of the blocks are appropriately sized.

27. A system as claimed in claim 26, wherein the at least one biscuit comprises two side walls spaced apart by a wall with an aperture formed therein to enable the passage of grout or any other core filling material.

28. A system as claimed in either claim 26 or 27, wherein the at least one biscuit also comprises projections, to which the connector may connect to connect the biscuit to the open end of one of the blocks.

29. A system as claimed in any one of claims 23 to 28, wherein the system also comprises a plurality of reinforcing rods to be positioned vertically and/or horizontally through the blocks in the structure.

30. A system as claimed in any one of claims 23 to 29, wherein the system also comprises grout or any other core filling material to fill the spaces in the structure built using the system.

Description:

A BLOCK AND A SYSTEM FOR OSE IN BUILDING A STRUCTURE

Field of the Invention

The present invention relates to a block for use in building a structure. The present invention also relates to a eystem for use in building a structure.

Background to the Invention

Various systems of blocks have been proposed for use in building walls or other structures. In a conventional block wall, the blockt? are laid in rows with each block overlapping portions of two blocka in the row below. Thiβ arrangement may be referred to as stretcher bond. Mortar is provided between adjacent blocks in the same row and in the rows above and below, aβ the blocks are laid, bonding the blocks together. This may be referred to as mortared masonry. Building a structure with this system, however, can be a time consuming process. A further issue is that all the cores in the blocks must be cleaned out of all mortar dags and droppings before the wall can be filled with grout.

One proposed system to reduce the time required to construct a structure is a "dry stack" system. In this system, the blocks, which have a cavity extending through the block, are stacked on top of one another with their cavities in alignment but without mortar to bond them together. This may be referred to as mortarless masonry. This enables a steel reinforcing rod and/or grout to pass through the cavities, bonding the blocks in columns together. Adjacent columns of blocks may be bonded together by connectors which extend across the end walls of at least some of the blocks which abut each other end to end or by keys which lock into vertical grooves in blocks which abut each other end to end. In other variations, horizontal grooves are provided in the end walls of the blocks which enable a steel reinforcing rod to extend horizontally across rows of blocks, connecting

them together .

Problems exist with these dry stack systems however, including that stacking blocks directly on top of one another does not form as strong a structure as when the blocks are laid in stretcher bond. Dry stacked blocks as described above are not readily stacked in such an overlapping arrangement because this puts the cavities out of alignment, making it difficult to completely fill the cavities with grout to bond the blocks together. A further problem which occurs is that because the cavities are not . completely filled with grout then the steel reinforcing rods may be exposed to air and moisture and thus become subject to corrosion, which can ultimately lead to the deterioration of the structure. In both mortared and mortarless concrete block construction not only is there a problem with providing adequate cover to the reinforcement rods, but there is also a problem in positioning and securing vertical rods clear of the inside surface of the blocks so that core fill grout can completely envelop the rods.

In mortared masonry construction the perpends of the blocks are not always completely filled with mortar and hence any rod situated in close proximity to the inside edge of the perpend is vulnerable to corrosion. Throughout the specification, the term "perpend" refers to the vertical joint between the ends of two blocks placed end to end. In addition, the term "bed joint" refers to the horizontal joint between two blocks placed one upon another. In mortarless masonry construction this problem is more pronounced as mortarless masonry blocks have unfilled perpends and unfilled bed joints when laid in a wall. Furthermore, the unfilled bed joints and perpends are of considerable width. Both the horizontal and the vertical reinforcing rods are often placed in very close proximity to the inside edge of the unfilled perpends and/or the unfilled bed joints. This means that very

often the embedded reinforcement rods are not adequately- protected against corrosion.

Summary of the Invention According to a first aspect of the present invention, there is provided a block for use in building a structure, the block comprising a body and at least one cavity extending through the body, the body having two side walls and at least one open end, the block also comprising at least one laterally extending wall extending between the two side walls and defining one end of the cavity, the at least one laterally extending wall having an aperture formed therein for enabling the passage of grout or any other core filling material from the at least one cavity to the at least one open end of the body when building the structure, wherein, inner corners of end edges of the side walls at the at least one open end of the block are chamfered, the chamfered end edges for forming a void between each of the side walls and the side walls of another block laid end to end with the block to enable grout or any other core filling material to be provided close to the outer faces of the block.

Because the block provides core filling grout close to the outer faces of each block, moisture and air penetration into the built structure is reduced.

In an embodiment, the block also comprises at least one pair of opposing chamfered projections, projecting from the side walls of the body. In an embodiment, the chamfered projections are located towards the at least one open end of the block.

In an embodiment, the chamfered projections project inwardly from the side walls, towards one another.

The chamfered projections are stepped back from the open end.

In an embodiment, the chamfers of the chamfered projections face outwardly from the open end of the block

In an embodiment, the chamfers are located on the innermost corner of each of the projections.

In an embodiment, the chamfered projections are in line with the at least one laterally extending wall such that the chamfered projections project from the side walls into the aperture of the laterally extending wall.

In another embodiment, the chamfered projections are spaced apart from the at least one laterally extending wall. In an embodiment, innermost corners of top edges of the side walls are chamfered, the chamfered top edges for forming a void between each of the side walls and the side walls of another block laid on top of the block.

In an embodiment, the block also comprises opposing flanges extending from the side walls.

In an embodiment, the opposing flanges are located towards the bottom of the block.

In an embodiment, the opposing flanges are located inside the at least one cavity. In another embodiment, the opposing flanges are located centrally with respect to the block.

In an embodiment, the opposing flanges are of increasing thickness towards the bottom of the block.

In an embodiment, the opposing flanges are of a substantially priβmatic triangular shape.

In an embodiment, the aperture of the at least one laterally extending wall is centrally located within the laterally extending wall.

In an embodiment, the aperture is a substantially V-shaped recess formed in the top of the laterally extending wall .

Generally, the aperture is substantially V-shaped to enable the block to be readily manufactured by moulding. The aperture may, however, be of any shape. In another embodiment, the aperture is in the form of an enclosed space formed through the laterally extending wall.

In an embodiment, the depth of the aperture at its lowest point is 25 to 50% of the height of the block, preferably, approximately 40%.

In an embodiment, the block comprises one open end and one closed end. However, in other embodiments, the block may comprise two open ends.

In an embodiment, the closed end comprises a wall extending the full height of the side walls.

In an embodiment, the closed end defines one end of the at least one cavity.

In an embodiment, an innermost corner of a top edge of the closed end is chamfered.

In an embodiment, the block also comprises opposing pairs of grooves formed in the side walls to enable the portion of the block between a pair of the grooves to be readily knocked out of one or both side walls.

In an embodiment, the opposing pairs of grooves are located towards the closed end of the block. In an embodiment, the block also comprises dimples on the top edges of the side walls in line with and corresponding to each of the grooves to enable connectors to connect the block to the open end of another block laid at right angles to the block. The connector connected to the dimples also enables correct alignment of a block laid above.

According to a second aspect of the present invention, there is provided a connector for connecting blocks together, the connector comprising an approximately rectangular base portion and four legs located at and extending from each corner of the base portion, the legs for engaging portions of the blocks .

In an embodiment, the base portion comprises four sloping walls arranged in a rectangle and angled inwardly. In an embodiment, the sloping walls of the base portion are shaped to add rigidity to the embodiment.

In an embodiment, the sloping walls of the base

portion are angled to ensure that a vertical reinforcing rod inserted through the opening in the base portion will be readily deflected inwardly as it is installed through successive vertically aligned connectors in a built structure.

In an embodiment, the sloping walls of the base portion are shaped to position vertical reinforcing rods sufficiently inwardly from the inside face of the side wall of the blocks. This ensures that a vertical reinforcing rod resting against the bottom edge of a sloping wall will always be substantially encased in grout when the blocks are filled with grout.

In an embodiment/ the sloping walls of the base portion are shaped to position vertical reinforcing rods sufficiently inwardly from the outside face of the block. This ensures proper and adequate corrosion protection of the reinforcing rods when the blocks are filled with grout .

In an embodiment, the connector also comprises end plates at opposing ends of the connector.

In an embodiment, each end plate comprises a pair of members joined by a web.

In an embodiment, the members of the end plates are each connected at right angles to one of the legs, forming right angled posts.

In an embodiment, the web of each end plate extends upwardly from the sloping walls at opposing ends of the connector.

In an embodiment, the web of each end plate has a groove formed therein for receiving and locating a horizontal reinforcing rod, which may pass through the connector when building a structure using blocks and the connector.

In an embodiment, the web has more than one groove formed therein.

In an embodiment, the connector also comprises tabs extending approximately perpendicularly between the

inner face of each member and the outer face of each leg. In an embodiment, the members are shaped with a taper towards the members at opposing ends to enable the members to have a clearance from portions of the blocks which the connector is connecting when the connector is initially inserted, but gain a tighter fit with the portions of the blocks as the connector is pushed down to its at-rest position.

In an embodiment, the legs are shaped with a taper away from the legs on opposing sides to enable the legs to have a clearance from portions of the blocks which the connector is connecting when the connector is initially inserted, but gain a tighter fit with the portions of the blocks as the connector is puβhed down to its at-rest position.

The engagement of the members and legs of the connector with portions of the blocks substantially prevents any longitudinal or transverse movement of the blocks with respect to each other. In an embodiment, the connector comprises substantial spaces between the legs to enable the passage of grout or any other core filling material through the connector.

Similarly, the connector alβo comprises substantial spaces between the members to enable the passage of grout or any other core filling material through the connector.

In an embodiment, the connector is manufactured of a resilient material. In an embodiment, the resilient material is a plastic resilient material, such as polypropylene or polyvinylchloride (PVC) for example.

According to a third aspect of the present invention, there is provided a system for use in building a structure, the system comprising a plurality of blocks according to the first aspect of the present, invention and at least one connector for connecting blocks together.

In an embodiment, the system comprises a plurality of connectors.

In an embodiment, the connector (s) is a connector (s) according to the Becond aspect of the present invention.

In an embodiment, the system alβo comprises at least one biscuit for filling a space in the structure for which none of the blocks are appropriately sized.

In embodiment, the at least one biscuit 'comprises two side walls spaced apart by a wall with an aperture formed therein to enable the pasβage of grout or any other core filling material.

In an embodiment, the at least one biscuit also comprises projections, to which the connector may connect to connect the biscuit to the open end of one of the .blocks .

In an embodiment, the system alβo comprises a plurality of reinforcing rods to be positioned vertically and/or horizontally through the blocks in the structure. The reinforcing rods may or may not be manufactured of steel.

In an embodiment, the Bystem also comprises grout or any other core filling material to fill the spaces in the structure built using the system.

Brief Description of the Drawings

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a series of views (top, bottom, side, end and perspective views) of a block for use in building a structure according to an embodiment of the present invention;

Figure 2 is a series of views (top, bottom, side, end and perspective views) of a block for use in building a structure according to another embodiment of the present invention;

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Figure 3 is a series of views (top, bottom, side, end and perspective views) of a block for use in building a structure according to yet another embodiment of the present invention; Figures 4, 5 and 6 are a series of views (top, bottom, side, .end and perspective views) of a block for use in building a structure according to further embodiments of the present invention;

Figures 7 and 8 are a series of views (top, bottom, side, end and perspective views) of connectors for use in connecting blocks when building a structure according to embodiments of the present invention;

Figure 9 is a series of views (top, bottom, side, end and perspective views) of a biscuit for use in building a structure according to an embodiment of the present invention;

Figures 10 and 11 are perspective views of walls built using blocks according to embodiments of the present invention; Figure 12 is a partial plan view of two blocks according to Figure 4 laid end to end in a wall;

Figure 13 is a cross-sectional side view through the perpends of a plurality of blocks according to Figure 4 constructed into a wall/ Figure 14 is a cross-sectional side view through the midway between the perpends of a plurality of blocks according to Figure 4 constructed into wall; and

Figure 15 is an exploded perspective view of a block according to Figure 4 being laid onto of other blocks with respect to a connector according to Figure 9.

Detailed Description of Embodiments

Referring firstly to Figure 1, a block 10 for use in building a structure according to an embodiment of the present is shown. The block 10 comprises a body 11 having two side walls 12 and 13 respectively, and open ends 18. The block also comprises a cavity 14 extending through the

body 11. It is understood that although, the block 10 is shown only comprising one cavity 14, that it may comprise more than one cavity. When building the structure, blocks 10 laid on top of one another may be joined together by passing a vertical reinforcing rod and/or grout or any other core filling material through their cavities 14. Preferably, the blocks are laid in a stretcher bond arrangement, in which the cavities 14 are vertically aligned in every second course. The block 10 alβo comprises laterally extending walls 15 extending between the two side walls, 12, 13 and defining the ends of the cavity 14. The laterally extending walls 15 each have an aperture 16 formed therein for enabling the passage of grout or any other core filling material from the cavity 14 to the open ends 18. The apertures 16 also provide a space for horizontally passing a steel reinforcing rod through blocks 10 which are abutting each other end to ' end. The laterally extending walls 15 are set back from the open ends 18 of the body 11, which means that when two blocks 10 are abutting end to end, an additional cavity is formed by the two open ends 18 of the abutting blocks 10. When building the structure, blocks 10 laid on top of one another may be joined together by passing a vertical reinforcing rod and/or grout or another core filling material through these additional cavities formed by blocks 10 abutting end to end. Preferably, the blocks are laid in a stretcher bond arrangement, in which the additional cavities are vertically aligned in every second course and also vertically aligned with the cavities- 14 in the intermediate courses .

Inner corners of end edges 21 of the side walls 12, 13 at the open ends 18 of the block 10 are chamfered. This feature enables the formation of a void when two blocks 10 are laid end to end (see for example Figure 12) . The void is readily filled with grout or any other core filling material during building of the structure, thus

providing grout closer to the outer face of the block 10. This means that the reinforcing rods are provided with greater cover (the distance from the edge of the grout to the rods) compared to conventional blocks and that the likelihood of oxygen (in the air) and moisture penetrating to the rods and causing corrosion of the rods is reduced.

The block 10 also comprises two pairs of opposing chamfered projections 17, projecting from the side walls 12, 13 of the body 11, located towards both ends of the block 10. The chamfered projections 17 project inwardly from the side walls 12, 13, towards one another. The chamfers of the projections 17 face outwardly from the ends of the block 10 and are located on the innermost corner of each of the projections 17. The chamfered projections 17 are located towards the open ends 18 of the body 11 but are stepped back from the open ends 18. The purpose of the chamfered projections 17 will become apparent further on in the specification.

Innermost corners of top edges 19 of the side walls 12, 13 are also chamfered. Grout or any other core filling material can fill the void created by the chamfered top edge 19 when one block 10 is laid upon another and thereby increase the effective load bearing area of a structure built using the blocks 10 compared to one built with conventional blocks. Furthermore, filling the void created by the chamfered top edge 19 also increases the cover provided to any reinforcing rod(s).

The block 10 also comprises opposing flanges 20 extending from the side walls 12, 13. The opposing flanges 20 are located inside the cavity 14, towards the bottom, of the block 10. The opposing flanges 20 are of increasing thickness towards the bottom of the block 10, and are thus of a prismatic triangular shape. The purpose of the opposing flanges 20 will also become apparent further on in the specification.

Referring specifically to the end views of Figure 1, the apertures 16 of the laterally extending walls 15

are centrally located within the laterally extending walls 15. The apertures 16 are in general alignment with one another in the embodiment shown in Figure 1, however, they need not be. The apertures 16 are each a substantially V- shaped recess formed in the top of the laterally extending walls 15. The apertures 16 are shaped this way to enable the block 10 to be readily manufactured by moulding. In a variation, one or both of the apertures 16 may be in the form of an enclosed space formed through the laterally extending walls 15. The apertures 16 may, however, be of any shape. The depth of the apertures 16 at their lowest point is 25 to 50% of the height of the block 10, preferably approximately 40%.

Referring now to Figure 2 a block 110 for use in building a structure according to another embodiment of the present invention is βhown, which is similar to the first-mentioned block 10 shown in Figure 1. Features of the block 110 which are similar to the features of the first-mentioned block 10 have been designated with the same reference numbers, but prefixed with the numeral 1.

The block 110 has only one open end 118 and one laterally extending wall 115. The other end of the block 110 is a closed end 122, comprising a wall extending the full height of the side walls 112, 113. The closed end 122 defines one end of the cavity 114. The innermost corner

123 of the top edge of the closed end 122 is chamfered. It is also noted that the opposing flanges 120 are not located centrally to the cavity, but are located centrally with respect to the block 110. The closed end 122 enables the block 110 to be used at the end of a wall for example.

The block 110 also comprises opposing pairs of grooves 124 formed in the side walls 112, 113 and, located towards the closed end 122. When the block 110 is laid at a corner or a T-intersection of walls, the portion of the block 110 between a pair of the grooves 124 can be readily knocked out of one or both side walls 112, 113 so that a horizontal reinforcing rod can extend across or around the

corner or T-intersection.

Referring now to Figure 3 a block 210 for use in building a structure according to another embodiment of the present invention is shown, which is similar to the first-mentioned block 10 shown in Figure 1. Features of the block 210 which are similar to the features of the first-mentioned block 10 have been designated with the same reference numbers, but prefixed with the numeral 2.

The block 210 also has only one open end 218 and one laterally extending wall 215 with the other end of the block 210 being a closed end 222. The laterally extending wall 215 is proximal to the open 218. The chamfered projections 217 are in line with the laterally extending wall 215 such that the chamfered projections 217 project from the side walls 212, 213 into the aperture 216 of the laterally extending wall 215. In the embodiments shown in Figures 1 and 2, the chamfered projections 17, 117 are spaced apart from the laterally extending wall(s) 15, 115. Referring now to Figures 4, 5 and 6, blocks 310, 410 and 510 for use in building a structure according to another embodiment of the present invention are shown, which are similar to the blocks 10, 110, and 210 respectively as shown in Figures 1, 2 and 3. The blocks 310, 410, 510 are slightly wider, and have thicker walls, than the blocks 10, 110, 210 of Figures 1 to 3. As a result the chamfered projections 317, 417, 517 project further inwardly from the side walls. Also, because the blocks 410, 510 have thicker walls, they are provided with dimples 425, 525 on the top edges of the side walls 412, 512, 413, 513 in line with and corresponding to each of the grooves 424, 524 to assist in being able to readily knocking out a portion of the block 410, 510 between a pair of the grooves 424, 524.

Referring now to Figure 7, a connector 40 for connecting blocks together according to an embodiment of the present invention is shown. The connector 40 comprises a base portion 41 consisting of four sloping walls 42,

arranged in a rectangle. The sloping wallβ 42 angle inwardly, which stiffens and strengthenβ the connector 40. The eloping walls 42 also act as a guide for any- reinforcing rod(β) which is passed vertically through the connector 40 when building the structure (such as a wall) . Notably, the angling of the sloping walls 42 (rather than being horizontal when in use) prevents the vertical reinforcing rods from catching on the base portion 41.

The connector 40 also comprises four legs 43, one leg located at and extending upwardly from each corner of the base portion 41 for engaging portions of the blocks. The connector 40 alβo comprises end plates 44 at opposing ends of the connector 40. Each end plate 44 comprises a pair of members 45 joined by a web 46. For each end plate 44, the members 45 are each connected at right angles to one of the legs 43, forming right angled posts. The web 46 of each end plate 44 extends upwardly from the sloping walls 42 at opposing ends of the connector AO. The web 46 of each end plate 44 has a groove 47 formed therein for receiving and locating a horizontal reinforcing rod, which may pass through the connector 40 when building a structure using blockβ and the connector 40.

The connector 40 also comprises tabs 48 extending approximately perpendicularly between the inner face of each member 45 and the outer face of each leg 43, ie. within each right angled post. The bottom surfaces of the tabs 48 are for. abutting the tops of the chamfered projections 17 of blocks 10 which abut each other end to end (see Figure 15 for example) . In this arrangement, the inner faces of the members 45 abut the inner faces of the chamfered projections 17 and the outer faces of the legs 43 abut the side faces of the chamfered projections 17. This arrangement securely locks the connecter 40 to each of the blocks 10 abutting each other end to end, preventing any substantial longitudinal or transverse movement of the blocks 10 with respect to each other prior to the blocks being filled with grout.

The members 45 are shaped with a taper towards the members 45 at opposing ends so that they have a clearance from the chamfered projections 17 in each block 10 when the connector 40 is initially inserted, but gain a tighter fit as the connector 40 is pushed down to its at- rest position, where the members 45 snugly and securely abut the inner walls of the chamfered projections 17.

Similarly, the legs 43 are shaped with a taper away from the legs on opposing sides so that they have a clearance from the chamfered projections 17 in each block 10 when the connector 40 is initially inserted, but gain a tighter fit as the connector 40 is puβhed down to its at- rest position, where the legs 43 snugly and securely abut the side walls of the chamfered projections 17. When a further block 10 is laid in a stretcher bond arrangement on top of two blocks 10 abutting end to end and connected by the connector 40, overlapping a portion of each of the two lower blocks (see Figure 15) , the opposing flanges 20 of the further block are received in each side of the connector 40, abutting the top surface of the tabs 48 on either side of the connector 40. In this arrangement the opposing flanges 20 also abut the inner faces of the members 45 and the outer faces of the legs 43 of the connector 40, preventing longitudinal and transverse movement of the further block with respect to the two lower blocks. The connector 40 thus aligns and secures the blocks 10 as they are laid in rows when building the structure.

It is noted that substantial spaces, and not walls, are provided between the legs 43 and between the members 45, which enables the passage of grout or any other core filling material through the connector 40 to fill the voids formed at the perpends when two blocks 10 are laid end to end. The connector 40 is manufactured of a resilient material, preferably a plastic resilient material such as polypropylene or polyvinylchloride (PVC) for example.

Referring now to Figure 8, a connector 140 for connecting blocks together according to another embodiment of the present invention is shown which is essentially identical to the connector 40 shown in Figure 7 except that it is sized to be used with the blocks 310, 410 and 510 shown in Figures 4, 5 and 6, whereas the connector 40 of Figure 7 is sized to be UBed with the blocks 10, 110 and 210 as shown in Figures 1, 2 and 3.

Referring now to Figure 9, a biscuit 50 for use in building a structure according to an embodiment of the present invention is shown. The biscuit 50 is particularly for use at a corner or T-intersection (see Figure 11) , where a "filler" may be required to fill a space for which none of the blocks described above are appropriately sized. The biscuit 50 comprises two side walls 12, 13 spaced apart by a wall 15 with an aperture 16 formed therein to enable the pasβage of grout or- any other core filling material. The biscuit 50 also comprises projections 17, to which a connector 40 may connect to connect the biscuit 50 to an open end 18 of a block 10.

Referring now to Figures 10 to 15, any or all of the blocks 10, 110, 210, 310, 410, 510, the connectors 40, 140 and the biscuit 50 may form a system which can be used to build a structure such as a wall. The blocks are laid end to end in rows, with generally, each block overlapping portions of two blocks in the. row below with connectors connecting at least some of and preferably all of the blocks together as described above.

As each row of blocks is laid, a horizontal reinforcing rod or rods 30 may be received in the grooves of the connectors 140. Once all the rows of blocks have been built, reinforcing rods 31 may be passed vertically through the cavities 314 of the blocks and the cavities formed by the open ends 318 of blocks abutting end to end. It is noted that because the blocks are laid in the overlapping arrangement that the cavity 314 of each block will overlay a cavity formed by the open ends 318 of two

abutting blocks. It is also noted that whilst it is not necessary to provide reinforcing rods either vertically or horizontally, that it is generally desirable to do so in order to increase the strength of the structure. Grout or any other core filling material is poured into the blocks, which because of the design of the blocks and the connectors, is able to substantially fill the cavities 314, the cavities formed by the open ends 318 of blocks abutting end to end and the voids formed by the chamfered projections 317, the chamfered inner top edges 319 of the side walls and the chamfered inner end edges 321 of the side walls of the blocks. This ensures that the vertical and horizontal reinforcing rods 30,31 are provided with the correct cover of 35-55mm. Furthermore, all dry joints, that is joints where the surfaces of blocks are in direct contact with the surfaces of adjacent blocks above, below and at both ends, are of minimal width, which provides maximum possible corrosion protection to the embedded reinforcement rods 30,31, and also a maximum effective load bearing area for the grouted structure.

It is noted that grout is readily able to fill all internal voids of the blockβ to within approximately 13 mm of the outside face of the blocks, with grout also penetrating the dry joints to provide even further protection to the embedded reinforcement rods 30,31.

In addition, the connectors are shaped to ensure easy and accurate positioning of the vertical reinforcing rods 31, and to ensure that the grout cover to any reinforcing rods 30,31 at the perpends and bed joints is at least 35 mm.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as

"comprises" or "comprising" is used in an inclusive sense, ie. to specify the presence of the stated features but not

to preclude the presence or addition of further features in various embodiments of the invention .