Composite material, components suitable for use in composite material and related methods and structures

Abstract

A composite material having a plurality of drainage members intersecting to provide interconnected fluid drainage paths.

Claims

1. A component for a composite material, the component comprising: a sheet structure including a plurality of tubular drainage members intersecting one another to provide internal fluid drainage paths that are mutually interconnected by a plurality of openings between the drainage members, wherein the mutually interconnected drainage paths are provided within the sheet structure creating a drainage member material formed by the intersecting drainage members, and wherein the plurality of openings comprise more than 50% of the cross sectional area of the component.

2. The component of claim 1, bounded by a drainage member along each of its edges.

3. The component of claim 1, wherein the fluid drainage paths are arranged to provide a continuous fluid path through the composite material in two non-parallel directions.

4. The component of claim 1, wherein fluid drainage paths of the component are all mutually interconnected.

5. The component of claim 1, wherein the drainage members are formed of crossing strips of drainage material.

6. The component of claim 5, wherein a fluid path is provided at the intersections between the strips of drainage material such that fluid can flow between the strips of drainage material.

7. The component of claim 1 wherein each opening in the component has a boundary comprising a drainage member.

8. The component of claim 1 wherein the drainage members comprise fluid drainage paths that form a first, micro drainage structure of the component, and the drainage members between openings in the component defines a macro drainage structure.

9. The component of claim 8 wherein the micro drainage structure is provided by the fluid drainage paths within the drainage member material.

10. The component of claim 1 wherein the fluid drainage paths are provided by fluid permeable portions of the component.

11. A composite material, the material comprising a first component in combination with a second component, wherein the first component is that of claim 1.

12. The component of claim 1, wherein the openings have a width dimension of greater than 50 mm across the component.

13. The component of claim 1, wherein the openings have a width dimension of greater than 100 mm across the component.

14. The component of claim 1, wherein the openings have a length dimension of greater than 50 mm across the component.

15. The component of claim 1, wherein the openings have a length dimension of greater than 100 mm across the component.

Description

BRIEF INTRODUCTION TO THE DRAWINGS

(1) For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which:

(2) FIG. 1 shows a side sectional view of a known composite material in use;

(3) FIGS. 2A and 2B show plan views of portions of components for a composite material, each in accordance with an example embodiment of the present invention;

(4) FIG. 3 shows a sectional view along line A-A of FIG. 2A, looking in the direction of the arrows;

(5) FIG. 4 shows an end view the component of FIG. 2A in combination with a second component to provide a composite material in accordance with an example embodiment of the present invention;

(6) FIG. 5 is a side sectional view of the component of FIG. 2A in use in a drainage structure according to an example embodiment of the present invention;

(7) FIG. 6 is a schematic plan view showing blockage of one drainage member and diverted flow in a component in accordance with an example embodiment of the invention;

(8) FIGS. 7A and 7B are schematic plan views of overlapping composite material sheets according to example embodiments of the present invention at the edges thereof to enable flow from one sheet into the next;

(9) FIGS. 8A and 8B are schematic plans views of other patterns of drainage members useful in alternative embodiments of the present invention;

(10) FIG. 9 is a schematic flow diagram illustrating a method of manufacturing a component for a composite material and of manufacturing a composite material according to example embodiments of the present invention; and

(11) FIG. 10 is a schematic flow diagram of a method of providing drainage using a composite material according to an example embodiment of the present invention.

DESCRIPTION OF EXAMPLE EMBODIMENTS

(12) FIGS. 2-8 show parts of components 2 and components 2 for a composite material in accordance with an example embodiment of the present invention. The components 2 comprise a sheet structure including a plurality of drainage members 4 intersecting one another to provide fluid drainage paths that are mutually interconnected.

(13) The components 2 of FIGS. 2A-7B are formed of crossing strips of drainage material. Each strip of drainage material comprises a drainage member 4, and the drainage members 4 are in fluid communication with one another at their intersections. FIGS. 2A, and 3-7B show groups of parallel drainage members 4 intersecting one another at right angles, with elements of one group arranged to lie on elements of the other group, and be attached thereto. FIG. 2B shows drainage members 4 that all lie substantially in one plane. FIGS. 8A and 8B show drainage members 4 that are interwoven with one another. Whereas the components 2 of FIGS. 2A and 3-8B comprise drainage members with internal capacity for providing fluid drainage paths, the component 2 of FIG. 2B provides a plurality of projections 20 extending from a first face 21 thereof. The spaces on the first face 21 and the spaces between the projections 20 define a plurality of interconnected fluid drainage paths 24 that allow fluid to run across the first face 21 of the component 2, to thereby form the drainage members 4. The component 2 further comprises a plurality of openings 26 defined therein to allow communication between the first face 21 and a second, opposite face.

(14) The component 2 is useful in a composite material for providing fluid drainage, for example in underground applications such as landfill capping. As shown in FIGS. 4 and 5 the composite material may include a second component 6 in the form of a water permeable coversheet. The second component 6 covers the entirety of the first component 2.

(15) FIG. 5 shows a side sectional view of the composite material of first and second components 2, 6 in use in a drainage structure. In this drainage structure a second face 22 of the first component 2 rests on a substantially impermeable membrane M, which itself lies on waste W. The second component 6 is fixed to the first face 21 of the core sheet 2 at the projections 20 and is in contact with moist soil S. The fluid drainage paths provided by the drainage members 4 are formed between the first face 21 of the first component 2 and the second component 6, and allow moisture from the soil S to run generally there-through within the first component 2 to facilitate drainage of moisture from the soil S. The weight of the soil S pressing on the second component 6 presses the second component down and through the openings in the first component 2 that fall between drainage members 4.

(16) In this way the relatively high frictional resistance to sliding of the second component 6 over the substantially impermeable membrane M is achieved, while maintaining good drainage performance using the drainage members 4 of first component 2. In embodiments where there is no fixed coupling between the first component 2 and the second component 6, again frictional engagement there-between to resist shearing forces is enhanced by the effect of the second component 6 pressing on the drainage members 4, e.g. the edges thereof. There are a number of factors in determining the degree to which the second component 6 extends into and through any openings between drainage members 4, including one or more of: the loading applied to the second component 6, the depth of the first component 2, the size and shape of any projections on the first component 2, the size of the openings, and the material properties of the second component 6. It will be appreciated that embodiments of the present invention provide to suitable combinations of these factors to work effectively in typical underground drainage situations where shearing loads may be a design consideration.

(17) Surprisingly, the presence of space in the first component 2 does not have a significant adverse affect on the drainage capacity provided in typical installations. However, the first component includes a smaller amount of material and is hence lighter than an equivalent material without openings. In addition to weight saving, the use of a smaller amount of material can reduce manufacturing costs.

(18) Furthermore, the mutual interconnection between fluid drainage paths in intersecting drainage members 4 enables the first component 2 to be resilient to blockage of drainage members 4, and furthermore facilitates installation of drainage structures using the first component.

(19) FIG. 6 shows a first component 2 in which a blockage B has prevented fluid flow along one fluid drainage path. The mutual interconnection of the blocked path with other intersecting mutually connected paths enables the drainage load to be shared by the remaining unblocked fluid flow paths, as shown by the dashed arrows indicating the direction of fluid flow.

(20) FIGS. 7A and 7B show drainage structures in which adjacent first components 2 are in non-parallel alignment and with offset drainage members respectively. In both cases, the fluid flowing out of the bottom edge of the higher one of the first components 2 is effectively collected into the fluid flow pathways of the lower one of the first components 2. The direction of fluid flow is generally indicated by the dashed arrows. The provision of drainage members that overlap one another contributes, as does the fact that the overlapping drainage members are generally at the edge of the first components 2. In general, overlapping of intersecting drainage members 4 to provide secondary drainage paths that are not parallel to the primary drainage direction contributes to the effectiveness of the drainage structures described herein, and the ease of installation thereof.

(21) FIG. 9 is a schematic flow diagram illustrating a method of manufacturing a first component 2 (steps S701 and S702) and of manufacturing a composite material (S703), according to example embodiments of the present invention.

(22) At step S701 a plurality of intersecting drainage members with fluid flow pathways provided thereon or therein is arranged such that the fluid flow pathways are mutually interconnected. The second step S702 comprises coupling the drainage members to one another, for example by heat bonding. In alternative methods of manufacturing, the first component may be formed by combining separate drainage members, e.g. by overlaying or weaving.

(23) In an alternative embodiment the first step S701 may comprise forming a sheet of material and the second step S702 may comprise forming openings therein to allow communication between the first face and the second face of the component. In such embodiments the second step S702 conveniently comprises stamping out the openings. In yet another alternative method of manufacturing, the openings may be formed or resized by stretching.

(24) At the third step the first component manufactured in steps S701 and S702 is combined with a second component, and optionally a third component to form a composite material. The third step S703 comprises bonding the components by adhering and/or welding. The cover sheet comprises a fluid permeable layer

(25) FIG. 8 is a schematic flow diagram of a method of providing drainage using a composite material according to an example embodiment of the present invention. The method comprises a first step S801 of installing a composite material as described herein on a substrate. The method further comprises the step S802 of placing material to be drained against the fluid permeable second component. The method may suitably further comprise providing a connection between the composite material and a further drainage structure to carry away fluid that enters into the composite material, for example by overlaying or butting up the composite material against a further sheet thereof.

(26) The components, composite materials and methods described herein are relatively cheap to produce and implement, offer easy installation, and address the problem of insufficient friction between components in the composite material and between a composite material and substrate.

(27) Although the embodiments described herein are intended primarily for drainage of water from moist soil, other related embodiments can also be envisaged as suitable for draining other fluids, including gasses, from other media. Furthermore, the embodiments described may be combined with other components, for example by addition one or more further layers, according to particular engineering requirements. Equally, although the embodiments described herein comprise interconnections between all fluid drainage paths, embodiment of the present invention may provide some non-interconnected drainage paths, and some non-draining elements.

(28) Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

(29) All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

(30) Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

(31) The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.