AU782613B2 - Retaining wall block - Google Patents

Description

S&FRef: 579712

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name and Address of Applicant *°oo oil Actual Inventor(s): Address for Service: Boral Masonry Limited Clunies Ross Street Prospect New South Wales 2148 Australia Kenneth Douglas Smith Spruson Ferguson St Martins Tower,Level 31 Market Street Sydney NSW 2000 (CCN 3710000177) Retaining Wall Block Invention Title: p I. ASSOCIATED PROVISIONAL APPLICATION DETAILS [33] Country [31] Applic. No(s) AU PR1616 The following statement is a full description of this invention, performing it known to me/us:- [32] Application Date 22 Nov 2000 including the best method of cc\. ~.7C~-21z e- 5815c pbO RETAINING WALL BLOCK Technical Field The present invention relates to a retaining wall block.

Background of the Invention Various forms of masonry wall blocks are known and used with varying success in different landscaping and embankment stabilising applications. Some retaining wall blocks are adapted to interlock with adjacent courses with a setback between courses to provide an inclined retaining wall. The setback counters backfill forces exerted by earth retained behind the wall so as to stabilise the same.

Some customers however prefer a "zero" setback retaining wall, meaning the wall extends vertically without a setback between courses for aesthetic considerations. Such a wall can be made by stacking wall blocks vertically using grout between the blocks or by using blocks with corresponding interlocking means, such as protrusions and recesses to interlock adjacent courses. A difficulty with forming a retaining wall vertically is that 15 backfill forces may force the wall to lean forward. Even a small 1 forward lean is aesthetically perceived as "falling".

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Object of the Invention It is the object of the present invention to overcome or substantially ameliorate at S "least one of the above disadvantages.

Summary of the Invention There is disclosed herein a retaining wall block having: a front wall, a rear wall, an upper surface, a lower surface; and ee e ~means for interlocking said retaining wall block with another said retaining wall block laid on said upper surface of said retaining wall block; wherein said upper and lower surfaces are configured to enable support of another said retaining wall block laid on said upper surface such that the front face of the laid block is inclined rearwardly with respect to the front face of said retaining wall block.

The upper and lower surfaces preferably each include a front support region and a rear support region, the front and rear support regions of the upper surface being for contacting the front and rear support regions, respectively, of the lower surface of another said retaining wall block laid on said retaining wall block, wherein the distance between the front support regions of the upper and lower surfaces is greater than the distance between the rear support regions of the upper and lower surfaces.

[R:\LIBLL I 0057.doc:FDP Preferably, the upper surface includes a protruding portion which incorporates the front support region of the upper surface. Alternatively or in addition thereto, the lower surface includes a protruding portion which incorporates the front support region of the lower surface.

In one form, the lower surface is substantially planar and the front support region in the protruding portion of the upper surface is substantially parallel to the lower surface. In this embodiment, the front support region preferably protrudes about 2 mm from the remainder of the upper surface. In another form, the front support region in the protruding portion of the upper surface lies on an inclined plane which intersects with the rear support region of the upper surface.

Alternatively, the upper surface is substantially planar and the front support region in the protruding portion of the lower surface is substantially parallel to the upper surface.

In this embodiment, the front support region preferably protrudes about 2 mm from the remainder of the lower surface. In another form, the front support region in the protruding portion of the lower surface lies on an inclined plane which intersects with the rear support region of the lower surface.

i In another embodiment, the upper and lower surfaces may be substantially planar and are inclined relative to each other to form the front and rear support regions.

The upper and lower surfaces are preferably configured such that the front face of'a laid said block is inclined rearwardly by an angle of 0.4' to The interlocking means in one form may include a lug formed in the upper surface and a corresponding recess formed in the lower surface or vice versa. The lug and recess are preferably elongated and extend generally parallel to said front wall. Alternatively, the interlocking means may comprise holes formed in the upper and lower surfaces for receiving pins. The interlocking means in another form may comprise a lip projecting beyond the lower surface adjacent the rear wall of the retaining block for abutment with the rear wall of another retaining block to which the retaining block is laid on.

There is further disclosed herein a retaining wall having: a plurality of courses of interlocked retaining wall blocks wherein the front face of each block which is laid on an underlying block is inclined rearwardly with respect to the front face of the underlying block.

Preferably, the front face of each laid block is inclined by an angle of 0.4' to with respect to the front face of the underlying block.

[R:\LIBLL] 10057.doc:FDP Brief Description of the Drawings Preferred forms of the present invention will now be described by way of examples only, with reference to the accompanying drawings wherein: Figure 1 is a plan view of a preferred embodiment of a retaining wall block according to the present invention; Figure 2 is a side view of the preferred embodiment shown in Fig. 1; Figure 3 is a perspective view of the preferred embodiment shown in Figs. 1 and 2; Figure 4 is a side view of three interlocked retaining wall blocks; Figure 5 is a side view of two nested pairs of retaining wall blocks prior to splitting; Figure 6 is a perspective view of an end block; and Figure 7 shows rear, plan, side, front and isometric views of a further embodiment of the retaining wall block according to the present invention.

Detailed Description of the Preferred Embodiments Figures 1 to 3 show a preferred embodiment of a retaining wall block 10 according to the present invention. The retaining wall block 10 includes a front wall 12, a rear wall 14, an upper surface 16 and a lower surface 18. The block 10 also has an elongated lug 20 formed in the upper surface 16 and a corresponding elongated recess 22 formed in the lower surface 18, both of which extend generally parallel to the front wall 12. The lug and recess 22 are for interlocking the block 10 with adjacent blocks 10 from adjacent courses as will be explained below.

The upper surface 16 includes a protruding portion 24 adjacent the front wall 12, which has a front support region 26 substantially parallel to the lower surface 18. The upper surface 16 also has a rear support region 28 adjacent the rear wall 14. Similarly, the lower surface 18 has a front support region 30 adjacent the front wall 12 and a rear support region 32 adjacent the rear wall 14. It can be seen that the distance between the front support regions 26, 30 of the upper and lower surfaces 16, 18 is greater than the distance between the rear support regions 28, 32.

Figure 4 shows three stacked retaining wall blocks 10, numbered as 10a, 10b and 10Oc, respectively. For clarity, the reference numerals for each block 10a, 10b and will include a corresponding suffix b or c, respectively).

The block 10a is laid on the upper surface 16b of the block 10b, which is laid on the upper surface 16c of the block 10c. It is to be understood that a laid block 10 does not have to cover the entire upper surface 16 of another block 10 as the blocks will usually be laid in a half-bond pattern. In this configuration, a laid block 10 is typically offset from [R:\LIBLL] 10057.doc:FDP the underlying block 10 by half their width to provide stability to the wall. It can be seen that the front and rear support regions 26c, 28c of the upper surface 16c of the block 1 Oc are contacting the front and rear support regions 30b, 32b of the lower surface 18b of the block 10b, respectively. Similarly, the front and rear support regions 26b, 28b of the Sblock 10 Ob are contacting the front and rear support regions 30a, 32a of the block 1 Oa.

Also, the lugs 20c and 20b of the blocks 10c and 10b are received in the recesses 22b and 22a of the blocks 10b and 10 Oa, respectively, which interlocks the adjacent blocks and 10b, and 10b and 10c. The lugs 20 and recesses 22 are dimensioned such that only the support regions 28 and 32 contact each other adjacent the rear wall 14. In the present embodiment, the lugs are 10 mm high and the recesses are 15 mm deep.

The greater distance between the front support regions 26c, 30c than between the rear support regions 28c, 32c of the block 10c supports the block 10b such that the front face 12b of the laid block O10b is inclined rearwardly with respect to the front face 12c of the block 10c, as indicated by angle 34bc. For the same reason, the front face 12a of the block 10a is inclined rearwardly with respect to the front face 12b of the block 10b, as indicated by angle 34ab. The difference in distance between the front support regions 26, "i 30 and the rear support regions 28, 32 is determined with respect to the length of the block 10 such that the angle of inclination 34ab, 34bc between the faces in this embodiment is about 0.50. The angle of inclination 34ab, 34bc between the blocks is ooeoo 20 preferably between 0.4' to In the present embodiment, the length of the block 10 is about 270 mm and the front support region 26 protrudes about 2 mm from the remainder of the upper surface 16.

The front support region 30 of the lower surface 18 of a laid block 10 will contact a rear portion 27 in the front support region 26 of the upper surface 16 of the underlying block 10 given that the laid block 10 will be inclined with respect to the upper surface front support region 26 of the underlying block 10. However, as the angle of inclination in the preferred embodiment is very small, the lower surface front support region 30 of the laid block 10 still contacts a large portion of the upper surface front support region 26 of the underlying block The inclination of the laid wall blocks ensure that when courses of wall blocks have been laid, the retaining wall will incline slightly rearwardly. The slight incline will provide a small counter to backfill forces exerted by earth retained behind the wall so as to stabilise the same. Also, even if backfill forces force the laid blocks forward, the front faces of the blocks will only be forced substantially in vertical alignment, which avoids a "falling" appearance for the retaining wall which would exist if no initial inclination was [R:\LIBLL] 10057.doc:FDP provided. If the backfill forces are not sufficient to bring the wall into vertical alignment, a slight rearward inclination will remain. Such a rearward angular inclination is still visually acceptable, avoiding the "falling" appearance.

Figure 5 shows two nested pairs 40, 50 of retaining wall blocks 10 prior to splitting.

Retaining blocks 10 are usually cast in such pairs 40, 50 face to face, to provide a decorative coarse finish for the front faces 12 after splitting of the pairs 40, 50 along chamfers 42, 52. In retaining wall blocks which provide a setback and which are mutually interlocked by corresponding lugs and recesses, the corresponding interlocking formations are offset from each other to provide the setback. For example, a recess in the lower surface will be spaced by a few millimetres further from the rear wall than the lug in the upper surface. The offset prevents such blocks from being nested prior to splitting as aligning of the rear walls of the unsplit blocks prevents the lugs from being received in the recesses. Stacking such unsplit blocks can therefore damage the lugs. However, as the blocks 10 of the preferred embodiment do not have the lugs and recesses offset to provide a setback, the pairs 40, 50 can be nested prior to splitting.

Figure 6 shows an end block 60 which is configured consistent with the blocks End block 60 has a front face 62 and side face 64 and is used as an end block for each course of retaining wall blocks 10 to provide a decorative finish.

Figure 7 shows orthogonal views of a further embodiment of a retaining wall block ol •i 20 70 according to the present invention, which has the following differences from the block The block 70 has a lug 72 formed in an upper surface 73 thereof which is thicker than the lug 20 of the block 10, in the front to rear direction of the block 70. A correspondingly larger recess 74 is formed in the bottom surface 76 of the block 70 for receiving the thicker lug 72. Grooves 78 formed in the rear wall 77 do not extend entirely 25 along the rear wall 77, as may be the case with the block 10. The internal radius 80 of the block 70 is larger, and the core cavity 82 is shorter, than that of the block 10. Such modifications allow the block 70 to be made of sand-cement mixes, rather than the coarse aggregate mix typically used for the block 10. Sand-cement mixes provide a sandstone appearance but are generally weaker than coarse aggregate mixes. Thus, the above modifications have been provided to ensure the strength of the block 70 is similar to the block 10 and that the lugs 72 do not break off.

Various further modifications can be made to the above embodiments.

For example, the lower surface 18 can include a protruding portion which incorporates the front support region 30 of the lower surface 18, instead of or in addition to the upper surface 16 having a protruding portion 24. The front support region 30 in the [R:\LIBLLJI0057.doc:FDP protruding portion of the lower surface 18 is preferably spaced about 2 mm from the rest of the lower surface 18.

In another alternative form, the lower surface 18 can be substantially planar and the front support region 26 in the protruding portion 24 of the upper surface 16 lies on an inclined plane which intersects with the rear support region 28 of the upper surface 16.

Alternatively, the upper surface 16 is substantially planar and the front support region in the protruding portion of the lower surface 18 lies on an inclined plane which intersects with the rear support region 32 of the lower surface 18. In either of these embodiments, the entire front support regions 26, 30 on the protruding portions will be aligned with and 1o contact the planar surface of an adjacent block In another alternative embodiment, the upper and lower surfaces 16, 18 can be substantially planar and inclined relative to each other to form the front and rear support regions 26, 28 and 30, 32. In such an embodiment, the upper and lower surfaces 16, 18 generally converge from the front wall 12 to the rear wall 14.

Also, the interlocking means between the blocks can be of any suitable form. One such available alternative comprises holes formed in the upper and lower surfaces for receiving pins, instead of the corresponding lugs and recesses. In this alternative embodiment, the pin is of a length greater than the depth of a hole in a surface such that the pin extends from the hole when inserted, and the extending part can be received in a o°••i S 20 hole of the adjacent surface to interlock the blocks. The interlocking means in another alternative form can comprise a lip projecting beyond the lower surface adjacent a rear wall of the retaining block for abutment with the rear wall of another retaining block to which the retaining block is laid on. This is particularly useful for blocks which provide a setback.

While the present invention has been described in relation to preferred embodiments, it will be apparent to persons skilled in the art that the invention may be embodied in other forms or that further modifications can be made to the above embodiments.

[R\LIBLLJ I 0057.doc:FDP

Claims (21)

1. A retaining wall block having: a front wall, a rear wall, an upper surface, a lower surface; and means for interlocking said retaining wall block with another said retaining wall block laid on said upper surface of said retaining wall block; wherein said upper and lower surfaces are configured to enable support of another said retaining wall block laid on said upper surface such that the front face of the laid block is inclined rearwardly with respect to the front face of said retaining wall block.

2. The retaining wall block of claim 1 wherein the upper and lower surfaces each 1o include a front support region and a rear support region, the front and rear support regions of the upper surface being for contacting the front and rear support regions, respectively, of the lower surface of another said retaining wall block laid on said retaining wall block, wherein the distance between the front support regions of the upper and lower surfaces is greater than the distance between the rear support regions of the upper and lower surfaces. 15

3. The retaining wall block of claim 2 wherein the upper surface includes a protruding portion which incorporates the front support region of the upper surface.

4. The retaining wall block of claim 3 wherein the lower surface is substantially planar and the front support region in the protruding portion of the upper surface is substantially parallel to the lower surface.

5. The retaining wall block of any one of claims 3 and 4 wherein the front support region protrudes about 2 mm from the remainder of the upper surface.

6. The retaining wall block of claim 3 wherein the front support region in the protruding portion of the upper surface lies on an inclined plane which intersects with the rear support region of the upper surface. 2i 5

7. The retaining wall block of any one of claims 1 to 6 wherein the lower surface includes a protruding portion which incorporates the front support region of the lower surface.

8. The retaining wall block of claim 7 wherein the upper surface is substantially planar and the front support region in the protruding portion of the lower surface is substantially parallel to the upper surface.

9. The retaining wall block of claim 8 wherein the front support region protrudes about 2 mm from the remainder of the lower surface.

The retaining wall block of claim 7 wherein the front support region in the protruding portion of the lower surface lies on an inclined plane which intersects with the rear support region of the lower surface. [R:\LIBLL] 10057.doc:FDP

11. The retaining wall block of claim 2 wherein the upper and lower surfaces are substantially planar and are inclined relative to each other to form the front and rear support regions.

12. The retaining wall block of any one of claims 1 to 11 wherein the upper and lower surfaces are configured such that the front face of a laid said block is inclined rearwardly by an angle of 0.4' to

13. The retaining wall block of any one of claims 1 to 12 wherein the interlocking means includes a lug formed in the upper surface and a corresponding recess formed in the lower surface.

14. The retaining wall block of any one of claims 1 to 12 wherein the interlocking means includes a lug formed in the lower surface and a corresponding recess formed in the upper surface.

The retaining wall block of any one of claims 13 and 14 wherein the lug and recess are elongated and extend generally parallel to said front wall.

16. The retaining wall block of any one of claims 1 to 12 wherein the interlocking means comprise holes formed in the upper and lower surfaces for receiving pins.

17. The retaining wall block of any one of claims 1 to 12 wherein the interlocking means comprises a lip projecting beyond the lower surface adjacent the rear wall of the retaining block for abutment with the rear wall of another retaining block to which the retaining block is laid on.

18. A retaining wall having a plurality of courses of interlocked retaining wall blocks wherein the front face.of each block which is laid on an underlying block is inclined rearwardly with respect to the front face of the underlying block.

19. The retaining wall of claim 18 wherein the front face of each laid block is 25 inclined by an angle of 0.40 to 20 with respect to the front face of the underlying block.

A retaining wall block substantially as hereinbefore described with reference to Figs 1 to 5; Fig.6; or Fig. 7 of the accompanying drawings. ooo.oi

21. A retaining wall substantially as hereinbefore described with reference to Fig 4 of the accompanying drawings. DATED this Third Day of June, 2005 Boral Masonry Limited Patent Attorneys for the Applicant ""SPRUSON FERGUSON o00o 9 9 oooa [R:LIBLL] 10057.doc:FDP