WO1994025679A1

WO1994025679A1 - Edging block

Info

Publication number: WO1994025679A1
Application number: PCT/CA1994/000213
Authority: WO
Inventors: David C. Bender; Steven C. Bender; Eugene M. Bender
Original assignee: Bender David C; Bender Steven C; Bender Eugene M
Priority date: 1993-04-28
Filing date: 1994-04-22
Publication date: 1994-11-10
Also published as: CA2095089A1; AU6562194A

Abstract

A cast concrete landscape or paving edging block (10) which comprises a top surface (11), a bottom surface (12), a pair of side surfaces (13, 14), a convexly curved end surface (15) and a concavely curved end surface (16), wherein said end surfaces (15, 16) are provided with alternating ridges (18) and grooves (17) extending between the top and bottom surfaces (11, 12). Such end surfaces (15, 16) are complementary, whereby the convexly curved end surface (15) of a block (10) is adapted to nest within the concavely curved end surface (16) of a line block (10) with the ridges (18) of one end surface nesting within the grooves (17) of the complementary end surface. In this manner, the adjacent edging blocks (10) resist both relative transverse displacement and relative angular displacement by reason of the nesting convex/concave end surfaces (15, 16), and against relative angular displacement by reason of the nesting ridges and grooves (17, 18).

Description

EDGING BLOCK BACKGROUND

This invention relates to an edging block for use particularly in paving and landscape construction. Edging blocks of the type to which this invention relates are principally useful in forming a straight or curving border along the edge of a, driveway, parking lot, pathway, patio or the like, composed of paving blocks or pavers, although they might also be useful in forming such a border or line of demarcation between a lawn and a flower garden or the like or between a lawn and a gravel pathway or patio, or the like. Indeed, edging blocks in accordance with the invention may be used to front the base of a retaining wall such as those formed of precast concrete blocks. The edging blocks in accordance with the invention may be used at the base course to resist sliding or lateral movement.

Typically, edging blocks are formed of cast concrete, and, where the edging blocks are for use in outlining a pathway, patio or the like composed of concrete paving blocks or pavers, the edging blocks are usually similar in appearance to the paving blocks in conjunction with which they are used. Typical, edging blocks are in the shape of a regular parallelepiped with rectangular top, bottom, side and end faces. Such blocks are simply placed end to end to define a border, and, because they do not interlock, one with the other, they can easily become misaligned thus resulting in the borders having an irregular and unattractive appearance. Similarly, because of their shape, such blocks are unsuitable for producing curved borders. Attempts have been made to overcome the aforementioned deficiencies by utilizing flexible edging strips of metal or plastic which consist of a vertical web, and a lateral projection which may be secured in position by means of a hold-down stake to maintain the vertical web in position. Such edging strips have the advantage that they can be arranged to follow either a straight or curved border. However, concrete units better support the growth of sod and plants, as concrete tends to remain cooler than synthetic materials at high temperatures, and the absorption of concrete provides more moisture to encourage plant growth along the border. Edging made of metal or plastic on the other hand tends to be impervious to moisture and this combined with a tendency to heat up at higher temperatures is not conducive to plant growth along such borders.

Edging blocks or curbing stones have been produced with curved ends, which are concave at one end and convex at the other so that the convex end of one block will nest within the concave end of a like block. This facilitates the production of curved borders, and also provides a degree of interlock as between adjacent blocks. However, the, adjacent blocks may still be subject to angular displacement as a result of lateral soil pressure, or lack thereof, or as a result of the effects of alternating freezing and thawing. Therefore such edging blocks may fairly readily become misaligned, and the borders formed thereby may lose their aesthetic or attractive appearance. SUMMARY OF INVENTION

We have found that some of the problems inherent in existing landscape or paving edgers may be overcome through the use of an edging block comprising a top surface, a bottom surface, a pair of side surfaces, a convexly curved end surface and a concavely curved end surface, wherein said end surfaces are provided with alternating ridges and grooves extending between the top and bottom surfaces. Such end surfaces are complementary, whereby the convexly curved end surface of a block is adapted to nest within the concavely curved end surface of a like block with the ridges of one end surface nesting within the grooves of the complementary end surface. In this manner, the adjacent edging blocks resist both relative transverse displacement and relative angular displacement by reason of the nesting convex/concave end surfaces, and against relative angular displacement by reason of the nesting ridges and grooves. The design is also such that, when standard jointing sand used to fill the joints between adjacent Interlocking concrete pavers is used to fill the joints between adjacent edging blocks, if concrete, additional lock-up is achieved, through friction, which further resists displacement of the edging blocks.

Such blocks may be relatively easily produced from cast concrete. It is also possible to produce such blocks from other natural materials such as wood, or from other materials such as plastics, rubber or the like. However, insofar as durability, stability, and function are concerned, cast concrete is the preferred composition.

It is also possible to provide such blocks with a blind hole extending from the top to adjacent the bottom surface, or a through hole extending from the top through to the bottom surface to accommodate the insertion of a hold- down spike which may be inserted through the through bore, or which may be inserted into the blind bore, and driven through the remainder of the block into the ground.

Further features and advantages of the novel edging block will be apparent from the detailed description which follows. Drawings In drawings which illustrate an embodiment of the invention: Figure 1 is a cross-sectional view of an edging block according to the invention installed adjacent a concrete paving stone walkway, Figure 2 is a cross-sectional view of an edging block in accordance with the invention, Figure 3 is a top plan view of a pair of interlocking edging blocks in accordance with the invention in straight alignment, Figure 4 is a top plan view of a pair of interlocking edging blocks in accordance with the invention displaced angularly, Figure 5 iε a plan view of a number of edging blocks in accordance with the invention arranged along a curved path or border. Detailed Description of Invention

Figure 2 illustrates the cross-section of a typical edging block 10 in accordance with the invention. The edging block 10 comprises a top surface 11 composed of a flat horizontal section 11a and a downwardly sloping section lib, and a flat bottom surface 12. The top and bottom surfaces extend between a relatively tall side surface 13 and a relatively short side surface 14. As illustrated in Figure 3, each block has a convexly curved end surface 15 and a concavely curved end surface 16. Both end surfaces are provided with a plurality of alternating grooves 17 and ridges 18 which extend from the top surface to the bottom surface.

The curved end surfaces are partially cylindrical in configuration, with the radius of curvature of the convex surface being slightly less than the radius of curvature of the concave surface to permit the concave surface to nest easily within the convex surface with sufficient clearance to permit angular displacement between the two, as illustrated in Figure 4. The vertically arranged alternating grooves and ridges may, as seen in Figures 3 and 4, be of a smoothly undulating or sinusoidal configuration in plan view of the block. When the blocks are formed of concrete, such a configuration is easier to cast without developing flaws in the curved end surfaces. However, it will be appreciated that the grooves and ridges could be of rectangular configuration, or of frustoconical configuration, or the like. For ease of reference, the curved end surfaces with the alternating grooves and ridges will be referred to as "ribbed", and preferably, the ribbed surfaces should be complementary in the sense that a convex end surface of one block will nest within the concave end surface of a like block with the ridges of one end nesting within the grooves of the abutting end when adjacent blocks are arranged in a straight line as Illustrated in Figure 3. In other words, a groove will be centrally disposed in one end surface of the block, whereas a ridge will be centrally disposed in the other end surface of the block so that when like blocks abut in a straight line connection, the centrally disposed ridge in the end surface of one block will nest within the centrally disposed groove in the end surface of the abutting block. This will tend to maintain the blocks in straight alignment against lateral pressures tending to displace one block with respect to the others.

As will be apparent from the foregoing, a border may be formed of a plurality of abutting blocks produced in accordance with the invention with abutting blocks being restrained against lateral displacement by virtue of the convex end of one block nesting within the concave end of an abutting block (or vice versa), and abutting blocks will also be restrained against angular displacement by virtue of the interlocking effect of the grooves and ridges of abutting blocks.

As illustrated in Figure 4, abutting blocks may be arranged with their longitudinal axes displaced angularly with the arrangement of ridges and grooves in the nesting curved ends of abutting blocks serving to permit fine adjustments in the angular relationship between abutting blocks, and to ensure, to the extent possible, that this angular relationship is maintained in use. As illustrated schematically In Figure 5, a smooth, irregularly curving border may be produced with the use of such edging blocks. It may also be possible to provide the edging block with a longitudinally ribbed bottom surface as illustrated in phantom at 12' in Figure 2. This bottom surface treatment will produce a degree of Interlock between the block and the support surface to resist transverse shifting of the block. Additionally, it may be important to hold the edging blocks securely against lateral displacement through the use of a hold-down spike or anchor pin 20 as illustrated in Figure 1. To this end, the blocks may be formed with a blind hole 21 which is countersunk slightly at 22 to permit a hold-down spike or anchor pin to be inserted in the blind hole and driven through the remainder of the block into the support surface below. Alternatively, it is possible to extend the hole 21 through the entire block to form a through bore through which the hold down spike or anchor pin may be inserted.

Figure 1 illustrates the manner in which the edging blocks 10 are used to form a retaining border or edge for a walkway composed of a plurality of conventional interlocking concrete paving stones 30. The paving stones rest in a bedding of sand 31 which in turn covers a compacted granular base 32 which extends laterally beyond the walkway border a sufficient distance to support the edging block 10. The base is surrounded below and laterally by the soil or earth subgrade 33 in which the walkway is being installed. The tall side 13 of the edging block Is disposed adjacent the paving stones 30 extending slightly above the height of the sand bedding layer 31 sufficient to abut the lower side edge of the adjacent paving stone to prevent lateral displacement of the paving stone. The edging stone 10 is then secured by means of anchor pin 20 and, when the walkway and edging has been completed, the abutting edging blocks are covered by soil and sod to the level of the walkway top, or slightly below, or, alternatively, the edging blocks may be covered by soil to be seeded for grass, or for floral or other plantings, or the covering may be decorative or natural aggregate, or any other suitable material.

The top side and end edges of the edging blocks may be chamfered as shown at 19 to remove unnecessary sharp edges, and facilitate handling during installation, and of course, it will be apparent that the alternating ridges and grooves in the curved end surfaces of the edging blocks may be sized to permit either fine or course angular adjustments between abutting blocks.

While the blocks may be made of any convenient size. Typically, the blocks may be about 325 millimetres in length and about 100 millimetres in width. The normal height at side 13 may be about 45 millimetres, whereas the height at side 14 may be about 25 millimetres. Of course the foregoing dimensions are exemplary only and may vary depending upon the thickness of the concrete pavers being retained or the particular application for the edger. However an edger with the foregoing dimensions could be used to retain the lawn side of any thickness of paver. As noted previously, while the edging blocks are preferably formed of cast concrete, they may be constructed of other materials such as wood, plastic, rubber, etc. If constructed in the form of hollow plastic shapes, the blocks would be provided with an access opening or fill hole to permit the blocks to be filled with sand, water, or the like to increase their weight and reduce the likelihood of undesired displacement. It will be appreciated that many features of the edging blocks described herein may be varied without departing from the scope of the invention.

Claims

1. An edging block comprising a top surface, a bottom surface, a pair of side surfaces, an end surface curving convexly between said side surfaces, and an end surface curving concavely between said side surfaces, said end surfaces being provided with alternating ridges and grooves extending between the top and bottom surfaces, and said end surfaces being complementary, whereby the convexly curved end surface of a block is adapted to nest within the concavely curved end surface of a like block with the ridges of one end surface nesting within the grooves of the complementary end surface.

2. An edging block as defined in claim 1, wherein said curved end surfaces are partially cylindrical in configuration.

3. An edging block as defined in claim 1 or 2, wherein said top surface adjacent one side surface is parallel with said bottom surface over a minor extent of its width, and slopes toward said bottom surface over a major extent of its width.

4. An edging block as defined in claim 3, wherein said parallel portion of said top surface extends over about

20% of the width of the block.

5. An edging block as defined in claim 1, 2 or 4, wherein said bottom surface is flat.

6. An edging block as defined in claim 1, 2 or 4, wherein said bottom surface is provided with a plurality of parallel ridges extending between said end surfaces.

7. An edging block as defined in claim 1, wherein said block is provided with a blind bore in said top surface between said side and end surfaces, said bore terminating adjacent to, but spaced from said bottom surface.

8. An edging block as defined in claim 1, wherein said top surface is provided with a through bore extending to said bottom surface and disposed between said end surfaces and side surfaces.

9. An edging block as defined in claims 7 or 8, wherein said bore is disposed about midway between the side surfaces and about midway between said end surfaces.

10. An edging block as defined in claim 1, wherein said curved end surfaces exhibit a substantially sinusoidal configuration to form said alternating ridges and grooves.

11. An edging block as defined in claim 1, 2, 4, 7, 8 or 10, wherein the edges formed at the junction of said top surface with said side surfaces and said end surfaces are chamfered.

12. An edging block as defined in claims 1, 2, 4, 7, 8, or 10 which is formed of cast concrete.

13. A cast concrete landscaping edging block comprising a top surface, a longitudinally ribbed bottom surface, a pair of flat side surfaces, an end surface of cylindrical convex curvature from one side surface to the other, and an end surface of cylindrical concave curvature from one side surface to the other, said curved end surfaces being provided with alternating grooves and ridges extending between said top and bottom surfaces, said end surfaces being complementary, whereby a convexly curved end surface of a block is adapted to nest within the concavely curved end surface of a like block with the ridges of one end surface nesting within the grooves of the complementary end ( surface when said blocks are in longitudinal alignment