Tufted geosynthetic with increased resistance to migration of infill granular material in a ground cover system

Abstract

A ground cover having a woven backing layer overlying a nonwoven underlayer tufted with yarns to form a plurality of rows of spaced-apart tufts extending as simulated blades of grass with interstices therebetween defining paths for flow of ambient water and plurality of needle-punched strands of the nonwoven underlayer extending in the interstices, and upon installation as a ground cover receiving an infill into the interstices and the needle-punched strands moderating the flow rate of ambient water flow and reducing infill migration.

Description

TUFTED GEOSYNTHETIC WITH INCREASED RESISTANCE TO MIGRATION OF INFILL GRANULAR MATERIAL IN A GROUND COVER SYSTEMTechnical Field

[0001] The present invention relates to ground cover systems of tufted geosynthtetics having infill granular material within interstices between adjacent tufts of simulated grass blades, which ground cover system for covering large area waste disposal landsites. More particularly, the present invention relates to ground cover systems for resisting migration of infill granular material along interstice pathways between adjacent rows of tufts extending as simulated blades of grass, which migration arises from shear forces of wind or ambient environmental water flow over the tufted ground cover system.Background Of The Invention

[0002] Large area land sites such as landfills and waste disposal sites have been overlaid with ground cover systems having a tufted geosynthetic featuring tufts of synthetic grass blades overlying an impermeable geomembrane for restricting inflow of ambient environmental water below grade into the ground.

[0003] While these cover systems work for restricting inflow of water into the ground and reducing land site maintenance, drawbacks arise from long term use of the cover system. The cover systems experience thermal expansion and contraction from sunlight and overnight thermal cooling. Cover system movement creates ridges of tufted geosynthetic. Ridges leaves portions of the backing sheet exposed to UV degradation. Movement also weakens the underlying backing sheet and may lead to rips or tears requiring repair. Ballast of granular infill spread into interstices4885-5525-2947vl2171320-00017908 / 04 / 2025between the tufts restricts but does not eliminate ground cover movement. Granular infill however migrates under hydroshear forces of ambient water flow and dry flow loading from wind. Migration of infill ballast forms a build-up of infill such as at ridges or slope transitions and leaves areas of the cover with reduced infill or open areas. Reduced infill or open areas exposes the ground cover to UV degradation.

[0004] Accordingly, there is a need in the art for an improved structural ground cover having improved resistance to migration of infill granular material. It is to such that the present invention is directed.Brief Summary Of The Invention

[0005] The present invention meets the need in the art by providing a ground cover system structured to reduce migration of infill granular material through and along interstice pathways between adjacent tufts of yarn extending from the ground cover as simulated blades of grass. More particularly, the present invention provides a tufted geosynthetic ground cover, comprising a woven backing layer and a nonwoven underlayer held together by a plurality of spaced-apart tuft rows in which each tuft row comprises a plurality of spaced-apart tufts of yam tufted through the nonwoven underlayer and the woven backing layer. The tufts define interstices between adjacent tufts and extend from an upper surface of the woven backing layer as simulated blades of grass. Each pair of adjacent tuft rows define an elongate pathway therebetween for flow of ambient environmental water. The ground cover includes a plurality of spaced-apart fibers rows. Each fiber row alternates with an adjacent tuft row and comprises a plurality of spaced-apart fiber bunches. Each fiber bunch has one or more fiber strands extending from the upper surface of the woven layer into the pathway intemiediate respective adjacent tuft rows. The one or more fiber 4885-5525-2947vl2171320-00017908 / 04 / 2025strands of the fiber bunch needle-punched from the nonwoven underlayer through the woven backing layer. The needle-punched stands define impediments in the flow paths and moderate rate of water flow to reduce or restrict infill migration.

[0006] In another aspect, the present invention provides a land area covered with a tufted geosynthetic ground cover, comprising a large area land site; and a ground cover overlying the larger area land site. The ground cover comprising:

[0007] a woven backing layer tufted with a plurality of spaced-apart tuft rows, each tuft row comprising a plurality of spaced-apart tufts of yarn tufted through the nonwoven underlayer and the woven backing layer, said tufts of yam defining interstices between adjacent tufts and extending from an upper surface of the woven backing layer as simulated blades of grass, each pair of adjacent tuft rows defining an elongate pathway therebetween for flow of ambient environmental water;

[0008] a nonwoven underlayer needle punched to define a plurality of spaced-apart fibers rows, each said fiber row alternating with an adjacent tuft row and comprising a plurality of spaced-apart fiber bunches, each fiber bunch having one or more fiber strands extending from the upper surface of the woven layer into the pathway intermediate respective adjacent tuft rows, said one or more fiber strands of the fiber bunch needle-punched from the nonwoven underlayer through the woven backing layer; and

[0009] a granular infill received in the interstices between the tufts and the fiber strands,

[0010] whereby said tufted geosynthetic ground cover overlying a ground surface resists migration of the granular infill along the pathways by interference blockages of the spaced-apart fiber bunches between the adjacent tuft rows.4885-5525-2947vl2171320-00017908 / 04 / 2025

[0011] In another aspect, the present invention provides a method of making a tufted geosynthetic ground cover, comprising the steps of:

[0012] positioning a backing layer over a nonwoven underlayer;

[0013] tufting a plurality of spaced-apart tuft rows with yarns extending through the nonwoven underlayer and the woven backing layer, each tuft row comprising a plurality of spaced-apart tufts of yam extending from an upper surface of the woven backing layer as simulated blades of grass tufted, said tufts defining interstices between adjacent tufts, and each pair of adjacent tuft rows defining an elongate pathway therebetween for flow of ambient environmental water; and

[0014] needle punching a plurality of spaced-apart fibers rows, each said fiber row alternating with an adjacent tuft row, each said fibers rows comprising a plurality of spaced-apart fiber bunches having one or more fiber strands extending from the upper surface of the woven layer into the pathway intermediate respective adjacent tuft rows, said one or more fiber strands of the fiber bunch needle-punched from the nonwoven underlayer through the woven backing layer.

[0015] Objects, advantages and features of the present invention will become readily apparent upon a reading of the detailed description in reference the drawings.Brief Description Of The Drawings

[0016] Fig. 1 illustrates a detailed enlarged perspective view of a tufted geosynthetic ground cover according to the present invention.

[0017] Fig. 2 illustrates a detailed enlarged side elevational view of the tufted geosynthetic ground cover according to the present invention overlying a ground surface.4885-5525-2947vl2171320-00017908 / 04 / 2025

[0018] Fig. 3 illustrates a detailed enlarged side elevational view of an alternate embodiment of a tufted geosynthetic ground cover system according to the present invention overlying a ground surface.

[0019] Fig. 4 illustrates a detailed enlarged side elevational view of an alternate embodiment of a tufted geosynthetic ground cover system according to the present invention overlying a ground surface.Detailed Description

[0020] With reference to the drawings in which like elements have like reference numerals, Fig.1 illustrates a detailed enlarged perspective view of a tufted geosynthetic ground cover 10 according to the present invention. The tufted geosynthetic ground cover 10 comprises a woven backing layer 12 and a nonwoven underlayer 14 held together as an elongated mat by a plurality of spaced-apart tuft rows 16. The woven backing layer 12 comprises polymeric yarns interwoven with weft and warp stands to define a permeable backing sheet. The nonwoven underlayer 14 may be made of a plurality of fibers that are air-laid, spun-bond, heat bonded, melt-blown, stitch- bonded, and other manufacturing processes, using polymeric and natural staple fibers and continuous fibers. The plurality of spaced-apart tuft rows 16 hold the backing layer 12 and the nonwoven underlayer 14 together as a flexible mat for ground cover purposes.

[0021] Each tuft row 16 has a plurality of spaced-apart tufts 20 formed with a yarn that extends through the nonwoven underlayer 14 and the woven backing layer 12. The tufts 20 extend from an upper surface 22 of the woven backing layer 12 as simulated blades 24 of grass. The spaced- apart tufts 20 and the spaced-apart tuft rows 16 define interstices 26. Each pair of adjacent tuft rows 16 thereby defines an elongate pathway 28 therebetween for flow of ambient environmental4885-5525-2947vl2171320-00017908 / 04 / 2025water. The pile in the illustrated embodiment is a cut loop to define the separate simulated blades 24..

[0022] The tufted geosynthetic ground cover 10 further comprises a plurality of spaced-apart fibers rows 30. The fiber rows 30 alternate intermediate respective adjacent tuft rows 16. Each of the fibers rows 30 comprises a plurality of spaced-apart fiber bunches 32. Each fiber bunch 32 has one or more elongated fiber strands 34 that extend from the upper surface 22 of the woven backing layer 12 into the pathway 28 intermediate respective adjacent tuft rows 16. The one or more fiber strands 34 of the fiber bunch 32 extend as needle-punched strands punched from the nonwoven underlayer 14 through the woven backing layer 12. The fiber strands 34 occupying an intermediate portion of the pathway 28 form impediments to flow therealong.

[0023] With reference to Fig. 2, the tufted geosynthetic ground cover 10 installs as a matting or covering 38 over a ground surface 40. The underlayer 14 lies in contacting engagement with the ground 40. The geosynthetic ground cover 10 receives a granular infill 42 in the interstices 26 between the tufts 20 and the fiber bunches 32. The fibers 34 of the fiber bunches 32 form impediments to flow of ambient water along the pathways 28. The fiber bunches 32 resist migration of the granular infill 42 along the pathways 28 by the interference blockages of the fibers 34 between the adjacent tuft rows. Reduced or restricted migration of infill leaves the infill substantially as installed and thereby reduces the development of open or infill-free portions of the ground that permits UV exposure to the backing layer and degradation over extended exposure.

[0024] The ground cover 10 receives ambient environmental water such as rain or other precipitation. Shear forces from the water flow, as well as wind flow across the tufted ground cover 10, induce movement or migration of the granular infill 42. The extending fiber strands 34 in the pathways 28 restrict infill migration as impediments that reduce flow velocity and portions 4885-5525-2947vl 2171320-00017908 / 04 / 2025of the infill 42 interlock with the strands. The interlocked infill resists migration. This also moderates the lateral flow of the ambient water across the ground cover and allows the ambient water to flow through the woven backing layer 12 and the nonwoven underlayer 14 into the covered ground.

[0025] Fig. 3 illustrates an alternate embodiment ground cover system 50 comprising the tufted geosynthetic ground cover 10 and a geomembrane 52 disposed under the tufted geosynthetic ground cover for overlying the ground surface. In a first embodiment, the geomembrane is impermeable. The geomembrane 52 defines a plurality of spaced-apart drainage components 54. The drainage components 54 space the geomembrane 52 from a bottom surface of the nonwoven underlayer 14 to define a flow path gap 56 therebetween. The ground cover 50 receives ambient environmental water such as rain or other precipitation. Shear forces from the water flow, as well as wind flow across the tufted ground cover, induce movement or migration of the granular infill 42. The extending fiber strands 34 in the pathways 28 restrict infill migration as impediments that reduce flow velocity and portions of the infill 42 interlock with the strands. The interlocked infill resists migration. The fiber stands 34 moderate the flow rate of the ambient water in the flow paths 28 across the ground cover and allows the ambient water to flow through the woven backing layer 12 and the nonwoven underlayer 14. The ambient water flows onto an upper surface of the geomembrane 52. The water then flows across the geomembrane 50 through the gap 56 between the geomembrane and the nonwoven underlayer 14 to drainage.

[0026] Fig. 4 illustrates a detailed enlarged side elevational view of an alternate embodiment of a tufted geosynthetic ground cover system. In this embodiment, the geomembrane 52 defines a plurality of spaced-apart openings 60. The number, spacing, and cross-sectional area of the 4885-5525-2947vl 2171320-00017908 / 04 / 2025openings 60 are selected for moderating through-flow of ambient water into the covered ground 40 below the geomembrane.

[0027] The nonwoven underlayer 14 in illustrative embodiments has a basis weight from 2 ounces per square yard to about 10 ounces per square yard. An exemplary but not limiting embodiment uses an airlaid nonwoven matting having a basis weight of 4 oz per square yard. Another exemplary but not limiting embodiment uses an airlaid matting with a basis weight of 6 oz per square yard.

[0028] In another aspect, the present invention provides a method of making a tufted geosynthetic ground cover, comprising the steps of:

[0029] positioning a backing layer over a nonwoven underlayer;

[0030] tufting a plurality of spaced-apart tuft rows with yarns extending through the nonwoven underlayer and the woven backing layer, each tuft row comprising a plurality of spaced-apart tufts of yam extending from an upper surface of the woven backing layer as simulated blades of grass tufted, said tufts defining interstices between adjacent tufts, and each pair of adjacent tuft rows defining an elongate pathway therebetween for flow of ambient environmental water; and

[0031] needle punching a plurality of spaced-apart fibers rows, each said fiber row alternating with an adjacent tuft row, each said fibers rows comprising a plurality of spaced-apart fiber bunches having one or more fiber strands extending from the upper surface of the woven layer into the pathway intermediate respective adjacent tuft rows, said one or more fiber strands of the fiber bunch needle-punched from the nonwoven underlayer through the woven backing layer.

[0032] The foregoing discloses tufted geosynthetic ground cover, comprising:

[0033] a woven backing layer;

[0034] a nonwoven underlayer;4885-5525-2947vl2171320-00017908 / 04 / 2025

[0035] a plurality of spaced-apart tuft rows, each tuft row comprising a plurality of spacedapart tufts of yam tufted through the nonwoven underlayer and the woven backing layer, said tufts of yarn defining interstices between adjacent tufts and extending from an upper surface of the woven backing layer as simulated blades of grass, each pair of adjacent tuft rows defining an elongate pathway therebetween for flow of ambient environmental water; and

[0036] a plurality of spaced-apart fibers rows, each said fiber row alternating with an adjacent tuft row and comprising a plurality of spaced-apart fiber bunches, each fiber bunch having one or more fiber strands extending from the upper surface of the woven layer into the pathway intermediate respective adjacent tuft rows, said one or more fiber strands of the fiber bunch needle- punched from the nonwoven underlayer through the woven backing layer.

[0037] The tufted geosynthetic ground cover further comprises a granular infill received in the interstices between the tufts and the fiber strands, whereby said tufted geosynthetic ground cover overlying a ground surface resists migration of the granular infill along the pathways by interference blockages of the spaced-apart fiber bunches between the adjacent tuft rows.

[0038] In an alternate embodiment, the tufted geosynthetic ground cover further comprises a geomembrane disposed under the tufted geosynthetic ground cover for overlying the ground surface.

[0039] In the alternate embodiment, the geomembrane of the tufted geosynthetic ground cover defines a plurality of spaced-apart drainage components, whereby ambient environmental water flows through the woven backing layer and the nonwoven underlayer onto an upper surface of the geomembrane for water flow to drainage off of the tufted geosynthetic ground cover.

[0040] In yet another alternate embodiment illustrated in Fig. 4, the geomembrane of the tufted geosynthetic ground cover defines a plurality of spaced-apart openings 60 or through passageways.4885-5525-2947vl2171320-00017908 / 04 / 2025The openings 60 allow for flow of the ambient environmental water, moderated by the impeding strands in the pathways, through the ground cover into the covered ground.

[0041] While the foregoing discloses the invention in illustrative embodiments of a tufted geosynthetic ground cover having improved resistance to migration of infdl granular material in interstices between adjacent tufts by impediment strands, it will be apparent to those skilled in the art that many modifications can be made therein without departing from the invention as defined by the appended claims.4885-5525-2947vl2171320-00017908 / 04 / 2025

Claims

CLAIMSWhat is claimed is:

1. A tufted geosynthetic ground cover, comprising: a woven backing layer; a nonwoven underlayer; a plurality of spaced-apart tuft rows, each tuft row comprising a plurality of spaced-apart tufts of yarn tufted through the nonwoven underlayer and the woven backing layer, said tufts of yarn defining interstices between adjacent tufts and extending from an upper surface of the woven backing layer as simulated blades of grass, each pair of adjacent tuft rows defining an elongate pathway therebetween for flow of ambient environmental water; and a plurality of spaced-apart fibers rows, each said fiber row alternating with an adjacent tuft row and comprising a plurality of spaced-apart fiber bunches, each fiber bunch having one or more fiber strands extending from the upper surface of the woven layer into the pathway intermediate respective adjacent tuft rows, said one or more fiber strands of the fiber bunch needle-punched from the nonwoven underlayer through the woven backing layer.

2. The tufted geosynthetic ground cover as recited in claim 1, further comprising a granular infill received in the interstices between the tufts and the fiber strands, whereby said tufted geosynthetic ground cover overlying a ground surface resists migration of the granular infill along the pathways by interference blockages of the spaced-apart fiber bunches between the adjacent tuft rows.4885-5525-2947vl2171320-00017908 / 04 / 20253. The tufted geosynthetic ground cover as recited in claim 2, further comprising a geomembrane disposed under the tufted geosynthetic ground cover for overlying the ground surface.

4. The tufted geosynthetic ground cover as recited in claim 3, wherein the geomembrane defines a plurality of spaced-apart drainage components, whereby ambient environmental water flows through the woven backing layer and the nonwoven underlayer onto an upper surface of the geomembrane for water flow to drainage off of the tufted geosynthetic ground cover.

5. The tufted geosynthetic ground cover as recited in claim 3, wherein the geomembrane defines a plurality of spaced-apart through passageways for flow of ambient environmental water through the ground cover in the cover ground.

6. A land area covered with a tufted geosynthetic ground cover, comprising: a large area land site; and a ground cover overlying the larger area land site, said ground cover comprising: a woven backing layer tufted with a plurality of spaced-apart tuft rows, each tuft row comprising a plurality of spaced-apart tufts of yam tufted through the nonwoven underlayer and the woven backing layer, said tufts of yarn defining interstices between adjacent tufts and extending from an upper surface of the woven backing layer as simulated blades of grass, each pair of adjacent tuft rows defining an elongate pathway therebetween for flow of ambient environmental water;4885-5525-2947vl2171320-00017908 / 04 / 2025a nonwoven underlayer needle punched to define a plurality of spaced-apart fibers rows, each said fiber row alternating with an adjacent tuft row and comprising a plurality of spaced-apart fiber bunches, each fiber bunch having one or more fiber strands extending from the upper surface of the woven layer into the pathway intermediate respective adjacent tuft rows, said one or more fiber strands of the fiber bunch needle-punched from the nonwoven underlayer through the woven backing layer; and a granular infill received in the interstices between the tufts and the fiber strands, whereby said tufted geosynthetic ground cover overlying a ground surface resists migration of the granular infill along the pathways by interference blockages of the spaced-apart fiber bunches between the adjacent tuft rows.

7. The tufted geosynthetic ground cover as recited in claim 6, further comprising a geomembrane disposed under the tufted geosynthetic ground cover for overlying the ground surface.

8. The tufted geosynthetic ground cover as recited in claim 7, wherein the geomembrane defines a plurality of spaced-apart drainage components, whereby ambient environmental water flows through the woven backing layer and the nonwoven underlayer onto an upper surface of the geomembrane for water flow to drainage off of the tufted geosynthetic ground cover.

9. The tufted geosynthetic ground cover as recited in claim 6, wherein the geomembrane defines a plurality of spaced-apart through passageways for flow of ambient environmental water through the ground cover in the cover ground.4885-5525-2947vl2171320-00017908 / 04 / 202510. A method of making a tufted geosynthetic ground cover, comprising the steps of:(a) positioning a backing layer over a nonwoven underlayer;(b) tufting a plurality of spaced-apart tuft rows with yarns extending through the nonwoven underlayer and the woven backing layer, each tuft row comprising a plurality of spaced-apart tufts of yarn extending from an upper surface of the woven backing layer as simulated blades of grass tufted, said tufts defining interstices between adjacent tufts, and each pair of adjacent tuft rows defining an elongate pathway therebetween for flow of ambient environmental water; and(c) needle punching a plurality of spaced-apart fibers rows, each said fiber row alternating with an adjacent tuft row, each said fibers rows comprising a plurality of spaced-apart fiber bunches having one or more fiber strands extending from the upper surface of the woven layer into the pathway intermediate respective adjacent tuft rows, said one or more fiber strands of the fiber bunch needle-punched from the nonwoven underlayer through the woven backing layer.4885-5525-2947vl2171320-00017908 / 04 / 2025

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