GB2167780A - Interlocking ground-surfacing blocks for sea walls - Google Patents

Abstract

Block 1 has upper and lower parts 10,11 each of which has two pairs of opposite edges. Parts 10 and 11 define two rebates 12, 13 along opposite edges of the block. The edges of one of the pairs of opposite edges of upper part 10 and vertically aligned with the corresponding pair of edges of lower part 11, rebates 12,13 extending from one set 9 of these vertically aligned edges to the opposite set 9. The other pair of opposite edges 14,15 of each part are contoured as at 16,17 so that the distance A between the contoured edges of each part is constant throughout their length. When laid, the blocks resist displacement both in and out of the plane of the surfacing. <IMAGE>

Description

SPECIFICATION A block four use in forming a surfacing on the ground The invention relates to a block for use informing a surfacing on the ground, e.g. a construction of revetments which are exposed to wave action on sea walls.

Interfitting blocksforuse in constructing revetments are described in British Patent No. 1509916 and have proved extremely successful in use. The present invention is an improvement on that set out in the above patent, which simplifies manufacture of the blocks and enhances the versatility of the blocks when interfitting to form a surfacing.

According to the invention there is provided a block shaped to interfitwith corresponding blockstoform a surfacing on the ground, the block having upperand lower parts each of which has two pairs of opposite edges, the upper part and lower part being arranged so as to define two rebates along opposite edges of the blockwhich enable the blockto overlap an adjacent block to resist displacement out ofthe plane ofthe said surfacing, one ofthe pairs of opposite edges ofthe upper part being vertically aligned with the corresponding pair of edges ofthe lower part with said rebates extending from one set of said vertically aligned edges to the opposite set, the other pair of opposite edges of each part being contoured to cooperate with contoured edges of adjacent blocks to resist relative displace e t ofthe blocks in the plane of the surfacing, the contours being so formed that the distance between the contoured edges of each part which co-operate with the contoured edges of the adjacent blocks is substantially constantthroughout their length.

Preferably, the vertically aligned edges of said parts are flat.

The block may be symmetrical about a vertical plane which passes throughthe contoured edges midway between the vertical Iy aligned edges.

The opposite contoured edges of each part of the block may be so formed that one edge includes a depression and the opposite edge includes a projection. In such a case, the depression and projection may be of complementary shape and may be opposite each other.

Preferably, the rebates are of equal depth. With such arrangementthe overlapping portions of adjacent blocks will be spaced from each other slightly in the vertical direction to facilitate laying and bedding down ofthe blocks on the ground. The depth of each rebate is preferably only slightly greater, e.g. around 1 mm or so,than halfthethicknessofthe block.

Each contoured edge of the block may include a plurality of surfaces contained in a vertical plane, two of which surfaces form respective corners with said vertically aligned edges and have lengths which are lessthan halfthe length of an intermediate surface in the same vertical place.

The invention also includes a surfacing on the ground formed from a pluralityofinterfitting blocks of the kind set out in any ofthe six immediately preceding paragraphs. The surfacing may include a further block having a contoured edgewhich co operates with a contoured edge of at least one ofthe first said blocks and which has a differently formed opposite edge forming a peripheral edge of desired form for the surfacing. The said peripheral edge may be flat. Preferably, the interfitted blocks are arranged so that the vertica lly alig ned edges of one block are spaced from the adjacent vertically aligned edges on an adjacent block.

Each of said upper and lower parts is preferably of generally rectangularform in plan with two opposite sides, e.g. relatively longer sides, of each rectangle defining the contoured edges.

Blocks in accordance with the invention will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 is a perspective view of one form of block in accordance with the invention.

Fig. 2,3 and 4 are plan, side and end views respectively of the block shown in Fig. 1; Fig. 5,6 and 7 are plan, side and end views respectively of a longer block in accordance with the invention; Figs. 8to 10 are plan, side and end views respectively of an edging block for cooperation with the blocks of Figs. 1 to7; Figs. 11 to 13 are views similarto Figs. 8to 10 showing an alternative edging block.

Fig. 14 is a scrap view showing part ofthe block of Fig. 1; and Figs. 15 and 16 illustrate sections of surfacing using blocks in accordance with the invention.

Forthe purpose of description, the block 1 shown in Fig. 1 will be considered as comprising an upper part 10 and a lower part 11 separated by a broken line B.

The parts 10,11 together define rebates 12,13 extending forthe full length of the block between ends ofthe block.

The ends of each part 10,11 are flat and lie in common planes to form a completely flat surface 9 at each end ofthe block. The biock is basically rectangu latin plan having its longer edges contoured as esilained below.

The longer edges 14, 1 5 of the upper part 10 are contoured by forming edge 14with spaced V-shaped depressions 16 and by forming edge 15 with complementary shaped projections 17. As shown clearly in Fig. 2 the depressions 16 and projections 17 lie directly opposite each other and the distance A between the edges 14, 15 is constantthroughout the length of those edges. The longer sides of the lower part 11 are formed in the same way. The block is symmetrical about a plan P passing through the countoured edges ofthe block midway between the ends.

As apparent from Fig.4, the depth D1 of rebate 12 is greaterthan half the thickness T of the block, e.g. by around 1 mm, and is equal to the depth D1 of rebate 13.

Typical depths D1 and D2 as illustrated in Fig. 4 are as follows: Thickness lT) ofblock Dl D2 150mm 76mm 74mm 200mm IOlmm 99mm 300mm 151 mum 149mm The difference in depth between D1 and D2 provides manufacturing toleranceforthe rebate depth and provides a spacing between overlapping portions of the blocks when assembled as described below which helpsthe blocks to bed onto the ground. However, if necessary, the depth ofthe rebates could be halfthe thickness ofthe block.

The block can be assembled with further blocks 1 and longer blocks 2 (Figs. 5 to 7). The principle of construction of longer blocks 2 is the same asthat of blocks 1 and enables the block 1,2 to be laid in staggered rows as in Figs. 13,14 giving maximum strength, pleasing appearance and straight side edges 7, one only of which is shown. The contoured edges of one blockcooperatewith the contoured edges of further blocks to inhibit or restrict movement in the plane ofthe surfacing and the overlap of adjacent blocks prevents the blocks from being lifted out ofthe surfacing. The assembled blocks in any one row define straight sided spaces 8 (e.g. around 8mm) between adjacent ends 9 ofthe blocks which facilitate drainage and release of hydrostaticpressureformthe underlying ground layer.Corresponding parts of blocks 1,2 carrythe same reference numerals in the drawings.

The spacing 8 is effected by making the lengths of straight side portions 14a, 14b; 1 Sal Sb, less than half the length Yofstraightside portions 14c; 15c respectivelythe side portions 75a, 15b and 15c, and 14a, 14b, 14c lying inthe respective common vertical planes.

The surfacing can be edged with edging blocks 3 and 4 ofthe kind shown in Figs. 8 to 13. The blocks recessed along one of the edges 18 only. The contours ofthe edge of block 3 are identical to those of block 1 and the contours ofthe edge 18 of block 4 are identical to those of block 2.The opposite edge 19 of each block 3,4 is flat although it may be of curved or otherform to give a desired border shape. Spaces 8 are defined between ends of adjacent edging blocks SB when assembled as in Fig. 15 or 16.In Figs. 15,16 only a front edge of each surfacing is shown formed by the edging blocks, the rear edge ofthe surfacing normally being laie eeneath a pre-formed overhang or being edged with concrete placed between the rear edge and adjacent walling such as a sea wall. The spcaing between the ends ofthe edging blocks is affected by making the distances X as shown in Figs. 8 and 11 less than half distances Y. Typical depths Dl, D2 ofthe edging blocks 3, 4correspond to the depths Dl, D2 of the co-operating blocks 1,2.

Fig.14showstheway in which the upper edges of upper part 10, and preferably the lower edges of lower part 11, are chamfered at2O to leave a small horizontal peripheral ledge 21.The chamfer enhances the appearance of the block and gives added resistance to damage the edges during manufacture and handling.

The symmetry of each block about a plane midway between its ends greatlyfacilitates identification and laying ofthe blocks and minimisesthe numberof blocks required forthe construction of rectangular panels. Moreover,theconstantwidths ofthe upper and lower parts ofthe block avoid wide and narrow areas giving the block consistent strength throughout its length, a particular advantage with longer block 2.

The flat ends 9 and constantwidth ofthe blocks 1,2 also simplifiestheform of mouid required for moulding the blocks from concrete or other suitable material. The use of flat ends also facilitates easy laying and fitting together of blocks.

Claims (16)

1. A block shaped to interfitwith corresponding blocks to form a surfacing on the ground, the block having upper and lower parts each ofwhich hastwo pairs of opposite edges, the upper part and lower part being arranged so as to define two rebates along opposite edges ofthe block which enable the blockto overlap an adjacent bl ock to resist displacement out of the plane ofthe said surfacing, one ofthe pairs of opposite edges ofthe upper part being vertically aligned with the corresponding pair of edges of the lower partwith said rebates extending from one set of said vertically aligned edges to the opposite set, the other pair of opposite edges of each part being contoured to cooperate with contoured edges of adjacent blocks to resist relative displacement ofthe blocks in the plane ofthe surfacing, the contours being so formed thatthe distance between the contoured edges of each partwhich co-operate with the contoured edges ofthe adjacent blocks is substantially constantthroughouttheir length.

2. A block according to Claim 1 in which the vertically aligned edges of said parts are flat.

3. A block according to Claim 1 or2which is symmetrical about a vertical plane which passes through the contoured edges midway between the vertically aligned edges.

4. A block according to any preceding claim in which the opposite contoured edges of each part of the block are so formed that one edge includes a depression and the opposite edge includes a projection.

5. A block according to Claim 4 in which the depression and projection are of complementary shape.

6. A block according to Claim 4 or 5 in which the depression and projection lie opposite each other.

7. A block according to claim 4,5 or 6 in which a plurality of depressions and projections are formed.

8. A block according to any preceding claim in which the depth of each rebate is greater than halfthe thickness ofthe block measured between upper and lower surfaces thereof.

9. A block according to any preceding claim in which the rebates are of equal depth.

10. A block according to any preceding claim in which each contoured edge of the block inciudes a plurality ofsurfaces contained in a vertical plane, two of which surfacesform respective corners with said vertically aligned edges and have lengths which are lessthan halfthe length of on intermediate surface in the same vertical plane.

11. Ablockshapedtointerfitwith corresponding blocks to form surfacing on the ground constructed and arranged substantially as described herein with reference to the drawings.

12. According to another aspect ofthe invention there is provided a surfacing on the ground formed from a plurality of interfitting blocks ofthe kind set out in any preceding claim.

13. A surfacing according to Claim 12 including a further block having a contoured edge which co operateswith a contoured edge of at leastone ofthe firstsaid blocks and which has a differently formed opposite edge forming a peripheral edge of desired form for the surfacing.

14. A surfacing according to claim 13 in which said peripheral edge is flat.

15. Asurfacing accordingtolaim ?30r'l4when appendantto Claim 9 in which the interfittedblocks are arranged so that the vertically aligned edges of one block are spaced from the adjacent vertically aligned edges of an adjacent block.

16. A surfacing on the ground constructed and arranged substantially as described herein with reference to Fig. 15 or 16 ofthe accompanying drawings.