GB1603510A

GB1603510A - Casing for a matress for lining or facing a land surface

Info

Publication number: GB1603510A
Application number: GB3048577A
Authority: GB
Original assignee: Intrusion Prepakt UK Ltd
Current assignee: Intrusion Prepakt UK Ltd
Priority date: 1978-05-31
Filing date: 1978-05-31
Publication date: 1981-11-25

Description

(54) IMPROVEMENTS RELATING TO A CASING FOR A MATTRESS FOR LINING OR FACING A LAND SURFACE (71) We, INTRUSION PREPAKT (U.K.) LIMITED, a Company registered under the laws of England, of Fieldings Road, Cadmore Lane, Cheshunt, Hertfordshire, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a casing for a protective mattress used for lining or facing a land surface, for example for protection against damage by erosion or scour. Such a mattress is usable for example for lining or facing a soil slope, an embankment, a beach, a river or canal bank, a hillside, a channel, etc., whether dry or under water.It is known to make such a protective mattress by filling a flexible mattress casing with a settable filling material such as cement grout or fine concrete.

According to the present invention, a fillable casing for a mattress for use in lining or facing a land surface, comprises an assembly of three superimposed plies of flexible sheet material, for example woven or knitted fabric, the intermediate ply being directly interconnected linearly with the upper ply along spaced parallel lines of interconnection, and with the lower ply along spaced parallel lines of interconnection which are also parallel to but are laterally staggered in relation to the lines of interconnection with the upper ply, the interconnections between the intermediate ply and each of the upper and lower plies being substantially continuous along the lengths of the respective lines of interconnection whereby the mattress casing when inflated by its filling will assume a ridged external surface formation on at least its upper surface, said formation comprising a series of parallel ridges disposed between adjacent lines of interconnection in the respective surface, and the intermediate ply being formed with multiple apertures distributed over its area.

In one construction, the intermediate ply may be of a material which is elastically extensible at least in directions transverse to the parallel lines of interconnection.

Thus, when the mattress casing is filled with a settable liquid filling material such as cement or fine concrete mix, the hydraulic pressure of the filling due to its weight and any filling pressure that may be imposed on it will inflate the casing and cause the intermediate ply to adopt a zig-zag configuration in section, so that the upper and lower plies will separate from one another whilst remaining interconnected by the "diagonal" portions of the intermediate ply. The filled mattress will have a ridged upper and possible also a ridged lower surface formation, whose ridges are caused by the inflation of the upper and lower plies between adjacent lines of interconnection by the pressure of the filling. However, the ridges of the upper and lower faces of the filled mattress will be in staggered relationship to one another.

Those of the lower ply will usually be at least partially flattened by the weight of the mattress resting on the supporting surface before setting.

In one arrangement the intermediate ply may be formed as an open-work net or mesh construction providing the specified distributed apertures.

It will normally be preferable for the lines of interconnection to be formed as lines of stitching of the respective superimposed plies. It may be possible to form the mattress casing by interweaving the respective plies along their required lines of interconnection during the weaving of the plies themselves and in the same loom, but this is expected to be difficult or expensive to achieve.

The invention resides not only in the novel mattress casing described above, but also in a protective mattress formed by such a casing filled with a settable filling material.

From another aspect, the invention further resides in a method of lining or facing a land surface with a protective mattress, comprising locating on the land surface a casing as referred to above, filling this with a settable filling material to inflate the casing whereby the intermediate ply assumes a zig-zag configuration in section and at least the upper surface of the filled casing assumes a ridged formation, and allowing the filling material to set hard.

The invention may be carried into practice in various ways, but one specific embodiment thereof will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 is a perspective view, in longitudinal section, of part of a filled mattress casing, and Figure 2 is a diagrammatic longitudinal section of the filled mattress.

In the illustrated embodiment, the mattress casing 10 comprises three woven or knitted fabric plies 11, 12 and 13 placed one upon another with their warp threads (if woven) extending in the direction of the length of the mattress, indicated by the arrow X, and joined together by two sets of stitching lines 14 and 15. Thus the upper and intermediate plies 11 and 12 are stitched together along equally-spaced parallel lines of interconnection 14 in this case extending in the length direction X of the casing 10, whilst the intermediate and lower plies 12 and 13 are stitched together along equallyspaced lines of interconnection 15 parallel to the lines 14.The sets of lines 14 and 15 are of equal pitch but are out of register with one another, i.e. laterally staggered, with each line 14 lying for example midway between two lines 15 as viewed in plan and vice versa.

Moreover, the upper and lower plies 11 and 13 are woven or knitted from non-elastic threads whilst the intermediate ply 12 is in this example woven or knitted from threads which, at least as regards the warp or longitudinal threads, are elastically-extensible. The intermediate ply 12 is of open-mesh net construction, or is formed with a pattern of apertures large enough to permit the free flow of the liquid filling material.

After the mattress casing has been stitched and before filling, the distance measured along the fabric material of the intermediate ply between alternate lines of stitching is the same as that measured along the upper or lower ply between adjacent lines of stitching, i.e. the plies will all lie flat and relaxed in the empty casing.The three plies are also all stitched together along one or more common lines of stitching- around the whole circumference of the mattress casing, to retain the filling material: The empty mattress casing 10 is placed on a sloping bank or other soil surface 22 to be protected, with the length of the casing and the lines of stitching 14, 15 extending up and down the slope, and is filled in situ with a suitable liquid cement or fine concrete grout, or other settable fluid filling material 20, under gravity or hydraulic pressure sufficient to cause the casing to be inflated to the form shown in the drawings with the intermediate ply 12 elastically stretched into a zig-zag configuration interconnecting the upper and lower plies.This forms the upper and lower surfaces of the mattress into a ridged configuration as shown, whose ridges 21, 21A extend up and down the slope and are formed between the lines of stitching 14 or 15, and being out of register. The filling 20 is allowed to set hard.

The resultant filled mattress thus has a minimum thickness of filling material determined by the distance between the planes of the upper and lower sets of stitching lines 14 and 15, i.e. the filling thickness is not zero at any point of the filled mattress. The thickness of the filled mattress, and the height of the upper and lower ridges, depend principally upon the pitch of the sets of parallel lines of stitching.

In a practical example of mattress casing prepared for testing, the casing was made of three fabric plies of knitted polyethylene thread, the intermediate ply 12 being of stretch fishnet construction. The two outer plies 11 and 13 were of closely-knitted construction, sufficiently porous to allow excess water from the filling mix to be expressed through the fabric under the pressure of the filling due to gravity.

The casing was placed on a sloping bank, and was filled under gravity with a liquid cement grout of the following constitution, delivered through a hose inserted through a filling opening in the upper part of the mattress: Sand 2 cwt.

Cement 1 cwt.

INTRUSION-AID Chemical additive i Kg.

Water content 3 gal. plus water content of damp sand Flow cone reading 25 secs.

Good flow of the grout throughout the casing was achieved, the intermediate ply stretching and offering no substantial flow resistance.

The filled casing took up the form shown in Figure 2, with the following average dimensions: A - unfilled distance between stitch lines of bottom and top plies = 100mm B - filled arc length between stitch lines of top ply = 112mm C - "diagonal" length of intermediate ply between stitching, filled = 75-90mm D - chord length at top ply = 95mm E - overall thickness =100--105mm F - base irregularity = 2O25mm G -- base flat length = 60mm H - thickness between top and bottom stitch lines = 5060mm The precise final form of the mattress after filling will depend on a number of factors, both dimensional and related to the constitu ency and filling pressure of the mix, but broadly speaking the overall thickness of the filled mattress will depend upon the pitch of the lines of stitching at the top and bottom ply and the degree of elasticity of the intermediate ply which determines the extent to which it will stretch under filling pressure.

Whilst in the example described and illus trated the intermediate ply 12 is made of elastically-extensible fabric, it is also possible and within the scope of the invention for the intermediate ply to be made of an inextensi ble apertured sheet material, i.e. inextensible net or open-mesh or apertured fabric. In such a case it is usually preferably for the interme diate ply of the casing to be of pleated or "bagged" form between adjacent stitch lines of the empty casing as stitched together, i.e.

arranged so that the length of the material of the intermediate ply between adjacent stitch lines 14, 15 is more than halfthe length ofthe material of the upper ply 11 between adja cent stitch lines 14 and more than half the length of the material of the lower ply 13 between adjacent stitch lines 15. This ensures that there is spare material available in the intermediate ply to allow the inflation of the casing to a suitable thickness on filling, with the intermediate ply adopting a zig-zag configuration. However, it is also possible for the three plies to be stitched together flat, i.e.

with the distances A of the upper and lower plies equal to twice the distance C of the intermediate ply in the empty casing giving a thinner filled mattress. Such a construction of casing is likely to be simpler and cheaper to manufacture.

While in the illustrated embodiment the empty mattress casing is placed on a sloping ground surface with its warp threads, and the lines of stitching 14, 15, extending up and down the slope, it is also possible to construct and use a mattress casing in which the lines of stitching 14 and 15 run across the width of the casing and in the weft direction. In that case the casing will be placed on the slope with the lines of stitching 14, 15 running horizontally across the slope instead of up and down the slope, and the ridge formations 21, 21 A of the filled mattress will be similarly arranged.

The INTRUSION-AID chemical additive referred to above is marketed in the United Kingdom by the Applicant Company.

WHAT WE CLAIM IS: 1. A fillable casing for a mattress for use in lining or facing a land surface, comprising an assembly of three superimposed plies of flexible sheet material, the intermediate ply being directly interconnected linearly with the upper ply along spaced parallel lines of interconnection, and with the lower ply along spaced parallel lines of interconnection which are also parallel to but are laterally staggered in relation to the lines of interconnection with the upper ply, the interconnections between the intermediate ply and each of the upper and lower plies being substantially continuous along the lengths of the respective lines of interconnection whereby the mattress casing when inflated by its filling will assume a ridged external surface formation on at least its upper surface, said formation comprising a series of parallel, ridges disposed between adjacent lines of interconnection in the respective surface, and the intermediate ply being formed with multiple apertures distributed over its area.

2. A casing as claimed in Claim 1 in which the plies are of woven or knitted fabric.

3. A casing as clained in Claim 2 in which the warp threads of the fabric plies are parallel to the lines of interconnection of the plies.

4. A casing as claimed in Claim 2 or Claim 3, in which the plies are interwoven along their lines of interconnection.

5. A casing as claimed in Claim 1 or Claims 2 or Claim 3 in which the lines of interconnection of the intermediate ply with the upper and lower plies comprise lines of stitching.

6. A casing as claimed in any preceding Claim, in which the intermediate ply is of a material which is elastically extensible at least in directions transverse to the lines of interconnection.

7. A casing as claimed in any of Claims 1 to 5, in which the intermediate ply is of substantially inextensible material, 8. A casing as claimed in any preceding Claim, in which the intermediate ply is formed as an open-work net or mesh construction.

9. A casing as claimed in any preceding Claim, in which adjacent lines of interconnection of the plies are equally spaced.

10. A casing as claimed in any preceding Claim, in which the lines of interconnection of the upper ply to the intermediate ply are midway between the lines of interconnection of the intermediate ply to the lower ply when viewed in plan.

11. A casing as claimed in Claim 7, or in any one of Claims 8 to 10 when depended on Claim 7, in which the intermediate ply is

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. intermediate ply between stitching, filled = 75-90mm D - chord length at top ply = 95mm E - overall thickness =100--105mm F - base irregularity = 2O25mm G -- base flat length = 60mm H - thickness between top and bottom stitch lines = 5060mm The precise final form of the mattress after filling will depend on a number of factors, both dimensional and related to the constitu ency and filling pressure of the mix, but broadly speaking the overall thickness of the filled mattress will depend upon the pitch of the lines of stitching at the top and bottom ply and the degree of elasticity of the intermediate ply which determines the extent to which it will stretch under filling pressure. Whilst in the example described and illus trated the intermediate ply 12 is made of elastically-extensible fabric, it is also possible and within the scope of the invention for the intermediate ply to be made of an inextensi ble apertured sheet material, i.e. inextensible net or open-mesh or apertured fabric. In such a case it is usually preferably for the interme diate ply of the casing to be of pleated or "bagged" form between adjacent stitch lines of the empty casing as stitched together, i.e. arranged so that the length of the material of the intermediate ply between adjacent stitch lines 14, 15 is more than halfthe length ofthe material of the upper ply 11 between adja cent stitch lines 14 and more than half the length of the material of the lower ply 13 between adjacent stitch lines 15. This ensures that there is spare material available in the intermediate ply to allow the inflation of the casing to a suitable thickness on filling, with the intermediate ply adopting a zig-zag configuration. However, it is also possible for the three plies to be stitched together flat, i.e. with the distances A of the upper and lower plies equal to twice the distance C of the intermediate ply in the empty casing giving a thinner filled mattress. Such a construction of casing is likely to be simpler and cheaper to manufacture. While in the illustrated embodiment the empty mattress casing is placed on a sloping ground surface with its warp threads, and the lines of stitching 14, 15, extending up and down the slope, it is also possible to construct and use a mattress casing in which the lines of stitching 14 and 15 run across the width of the casing and in the weft direction. In that case the casing will be placed on the slope with the lines of stitching 14, 15 running horizontally across the slope instead of up and down the slope, and the ridge formations 21, 21 A of the filled mattress will be similarly arranged. The INTRUSION-AID chemical additive referred to above is marketed in the United Kingdom by the Applicant Company. WHAT WE CLAIM IS:

1. A fillable casing for a mattress for use in lining or facing a land surface, comprising an assembly of three superimposed plies of flexible sheet material, the intermediate ply being directly interconnected linearly with the upper ply along spaced parallel lines of interconnection, and with the lower ply along spaced parallel lines of interconnection which are also parallel to but are laterally staggered in relation to the lines of interconnection with the upper ply, the interconnections between the intermediate ply and each of the upper and lower plies being substantially continuous along the lengths of the respective lines of interconnection whereby the mattress casing when inflated by its filling will assume a ridged external surface formation on at least its upper surface, said formation comprising a series of parallel, ridges disposed between adjacent lines of interconnection in the respective surface, and the intermediate ply being formed with multiple apertures distributed over its area.

7. A casing as claimed in any of Claims 1 to 5, in which the intermediate ply is of substantially inextensible material,

8. A casing as claimed in any preceding Claim, in which the intermediate ply is formed as an open-work net or mesh construction.

pleated or bagged between its adjacent lines of interconnection.

12. A casing as claimed in any preceding Claim, in which the three plies are also secured to together along one or more common lines around the perimeter of the casing.

13. A fillable casing for a mattress for use in lining or facing a land surface and constructed substantially as herein specifically described with reference to the accompanying drawings.

14. A mattress for facing or lining a land surface, comprising a casing as claimed in any preceding Claim containing a settable filling material in the set condition.

15. A mattress as claimed in Claim 14, in which the filling material is cement grout.

16. A mattress as claimed in Claim 14, in which the filling material is a fine concrete grout.

17. A mattress as claimed in any one of Claims 14 to 16, positioned on a slope with the lines of interconnection running up and down the slope.

18. A mattress as claimed in any one of Claims 14 to 16, positioned on a slope with the lines of interconnection running horizontally across the slope.

19. A method of lining or facing a land surface with a protective mattress, comprising locating on the land surface a casing as claimed in any of Claims 1 to 13, filling this with a settable filling material to inflate the casing whereby the intermediate ply assumes a zig-zag configuration in section and at least the upper surface of the filled casing assumes a ridged formation, and allowing the filling material to set hard.

20. A method as claimed in Claim 19, in which the casing is filled with the filling material by gravity.

21. A method as claimed in Claim 19, in which the casing is filled with the filling material by pumping the filling material into the casing under pressure.

22. A method of lining or facing a land surface substantially as herein specifically described with reference to the accompanying drawings.