HYBRID GRASS SUPPORT STRUCTURE WITH STONE WOOL LAYER

Abstract

A hybrid grass support structure (100, 200, 300, 400, 500, 600, 710) comprising a growth medium layer (102), a stone wool layer (104) positioned below the growth medium layer, and a plurality of synthetic grass fibers (106). The growth medium layer comprises a growth medium. The synthetic grass fibers are incorporated at least into the growth medium layer.

Claims

1. A box made of a biodegradable material, the box comprising a hybrid grass support structure comprising: a growth medium layer, the growth medium layer comprising a growth medium a stone wool layer positioned below the growth medium layer; and a plurality of synthetic grass fibers incorporated at least into the growth medium layer and also into the stone wool layer.

2. The box of claim 1, wherein the growth medium layer is selected from a group comprising sand, soil, an organic granulate, and a mixture of two or more of the foregoing.

3. The box of claim 1, wherein the growth medium layer comprises grass seed.

4. The box of claim 1, wherein the growth medium layer comprises a binding agent.

5. The box of claim 1, wherein the biodegradable material comprises cardboard.

6. The box of claim 1, wherein the box is stackable with boxes of the same type.

7. The box of claim 1, wherein the box has a base surface size smaller than 1 square meter.

8. A hybrid grass comprising: a hybrid grass support structure comprising: a growth medium layer, the growth medium layer comprising a growth medium a stone wool layer positioned below the growth medium layer; and a plurality of synthetic grass fibers incorporated at least into the growth medium layer and also into the stone wool layer; and natural grass plants, wherein the natural grass plants comprise roots growing at least between the grains of the growth medium layer and the synthetic grass fibers.

9. A method of installing a hybrid grass support structure at a site, the method comprising: applying a layer of stone wool on a ground at the site; applying a growth medium onto the applied stone wool layer for providing a growth medium layer; incorporating a plurality of synthetic grass fibers into at least the growth medium layer and also into the stone wool layer.

10. The method of claim 9 further comprising: positioning a plurality of boxes adjacent each other such that an area of adjacent tiles is formed, each tile being one of the boxes; and allowing the boxes to degrade.

11. The method of claim 9, further comprising growing natural grass plants in the installed hybrid grass support structure to provide a hybrid turf.

12. A hybrid grass support structure comprising: a growth medium layer, the growth medium layer comprising a growth medium a stone wool layer positioned below the growth medium layer; and a plurality of synthetic grass fibers incorporated at least into the growth medium layer and also into the stone wool layer.

13. The support structure of claim 12, wherein the growth medium layer is selected from a group comprising sand, soil, an organic granulate, and a mixture of two or more of the foregoing.

14. The support structure of claim 12, wherein the growth medium layer comprises grass seed.

15. The support structure of claim 12, wherein the growth medium layer comprises a binding agent.

16. The support structure of claim 15, wherein the binding agent comprises a biodegradable, plant-based binding agent.

17. The support structure of claim 12, wherein the stone wool layer comprises basalt.

18. The support structure of claim 12, wherein the stone wool layer has a height of at least about 0.3 cm.

19. The support structure of claim 12, further comprising a drainage layer below the stone wool layer, the drainage layer comprising a perforated layer or a tilted layer.

20. The support structure of claim 12, wherein the growth medium layer has a height of less than about 6 cm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0073] FIG. 1 shows a hybrid grass support structure;

[0074] FIG. 2 shows another hybrid grass support structure;

[0075] FIG. 3 shows a hybrid grass support structure with an elastic layer;

[0076] FIG. 4 shows a hybrid grass support structure with a drainage layer;

[0077] FIG. 5 shows a further hybrid grass support structure;

[0078] FIG. 6 shows another hybrid grass support structure;

[0079] FIG. 7A shows a single biodegradable, stackable box;

[0080] FIG. 7B shows a stack of two biodegradable boxes;

[0081] FIG. 7C shows a hybrid turf support structure formed by multiple boxes;

[0082] FIG. 8A depicts tufted fibers;

[0083] FIG. 8B is an illustration of a fiber-injection process;

[0084] FIG. 9 is a flowchart of a method for installing a hybrid grass support structure;

[0085] FIG. 10 is a flowchart of an alternative method for installing a hybrid grass support structure;

[0086] FIG. 11A depicts a box containing a hybrid grass support structure; and

[0087] FIG. 11B depicts the box containing hybrid grass.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0088] Like-numbered elements in these figures are either equivalent elements or elements that perform the same function. Elements that have been discussed previously will not necessarily be discussed in later figures if the function is equivalent.

[0089] FIG. 1 shows a hybrid grass support structure 100. It comprises at least a growth medium layer 102, a stone wool layer 104, and synthetic fibers 106. The growth medium layer comprises a growth medium, i.e., a medium allowing grass plants to grow roots in this medium. For example, the medium in the layer 102 can be sand, soil, organic granulate, or mixtures of two or more of the foregoing. The growth layer may in addition contain grass seed 108, fertilizers, fungicides, herbicides and further substances, which can be intermixed with and be homogeneously distributed within the growth medium as illustrated in FIG. 1 for the grass seed 108.

[0090] The stone wool layer is preferably positioned directly below the growth medium layer. This may ensure that capillary forces can soak water from the stone wool layer 104 into the growth medium layer 102 containing all or at least a significant portion of the roots of the natural grass plants that will be grown in the structure 100. Thereby, the system ensures that the roots are continuously provided with water that is stored in the stone wool layer, whereby the preferably granular structure of the growth medium ensures that no anaerobic conditions arise in the growth medium layer 102 that could cause a rotting of the roots.

[0091] The plurality of synthetic grass fibers 106 are incorporated at least into the growth medium layer, as depicted in FIGS. 1, 2, and 3.

[0092] After installation of the support structure 100 at the use site, the structure is exposed to rain or is repeatedly irrigated. Grass roots are allowed to intertwine with the mix of growth medium and synthetic fibers as they grow.

[0093] Preferably, the fibers 106 are integrated in addition into at least a portion of the stone wool layer as depicted in FIGS. 4 and 5 or into the whole stone wool layer as depicted in FIG. 6. The higher the growth medium layer and the deeper the fibers are incorporated into the growth medium layer and optionally also the stone wool layer, the stronger the fibers are fixed into the hybrid grass support structure and the more robust the hybrid grass is against wear and tear induced by mechanical stress.

[0094] Various methods for integrating synthetic fibers into a hybrid grass support structure can be used.

[0095] According to some embodiments, the synthetic fibers 106 are injected into the growth medium by a fiber-injection machine. For example, the injection can be performed at a factory. However, this has the downside that the growth medium layer has to be transported to the use site. This increases transportation costs and complicates the installation. Therefore, the fiber injection is preferably performed at the use site by a mobile fiber-injection machine.

[0096] According to other embodiments, the fibers are tufted into the growth medium layer and optionally also the stone wool layer by a tufting machine. The tufting machine can be located at a plant, or it can be a mobile tufting machine used at the use site.

[0097] According to a further embodiment, the synthetic fibers and the growth medium are mixed in an automated plant and are installed afterward on the pitch. This process is known as Fibresand.

[0098] According to a further embodiment, the synthetic fibers are integrated into a mat, e.g., by tufting or weaving the fibers into the mat. Then, the mat is placed onto the stone wool layer and the growth medium is applied onto the mat and brushed in between the synthetic fibers afterward to keep the fibers in an upright position. The growth medium can be applied onto the mat at the plant or, alternatively, at the use site after installation of the stone wool layer and the mat, on the ground. Finally, the grass seed, which is already contained in the growth medium or is added later, is allowed to germinate and grow. The natural grass roots grow through the mat and stabilize the system.

[0099] Hence, in some embodiments, there are one or more additional material layers between the stone wool layer and the growth medium layer, e.g., a synthetic fiber mat having incorporated the synthetic fibers. Preferably, these additional layers are thin, preferably thinner than 0.5 cm, and are adapted to allow the soaking of water stored in the stone wool layer into the growth medium layer.

[0100] The stone wool layer is an elastic layer that is adapted to reduce the risk of injuries for players and ease maintenance for groundskeepers. Because of this, the hybrid grass support structure is preferably free of additional elements to enable softness.

[0101] The stone wool layer preferably has a height of at least 0.3 cm. For example, a stone wool layer having a height in the range of 3 to 10 cm, more preferably in the range of 5 to 10 cm, is adapted to store a sufficient amount of water to ensure a continuous water supply to the plant roots at typical irrigation rates, such as once a day, and in addition provides sufficient elasticity to minimize the risk on injuries of the joints of the players from injury.

[0102] FIG. 2 shows another hybrid grass support structure 200 that is similar to the structure 100 depicted in FIG. 1 and differs from the hybrid grass support structure 100 only in that the grass seed 108 is not intermixed with the growth medium but rather is added on top of the growth medium layer, e.g., before delivering the structure 200 to a customer or during or after installation of the structure 200 at the use site.

[0103] FIG. 3 shows a hybrid grass support structure 300 with an elastic layer 302, e.g., a layer consisting of an elastic mixture of a hardened, polyurethane-based binder and rubber granulate. Typically, thanks to the elasticity of the stone wool layer (and also to some degree of the growth medium layer), an additional elastic layer is not needed and is not part of the hybrid grass support structure. However, in application scenarios where a particularly high elasticity is required or where the height of the stone wool is small, e.g., less than 1 cm, an additional elastic layer may improve the elasticity of the artificial turf.

[0104] FIG. 4 shows a hybrid grass support structure 400 with a drainage layer 402. For example, the drainage layer can be a basic plane, such as a horizontal plastic plane (e.g., a polyethylene foil plane), containing one or more drainage openings 404. Alternatively, the drainage layer 402 can be a tilted plane or a layer comprising one or more “V”-shaped kinks that guides surplus water that cannot be absorbed and stored by the stone wool layer to the ground onto which the hybrid grass support structure is installed. In some embodiments, the ground where the hybrid grass support is installed contains a drainage system with multiple pipes, channels, and/or grooves, and the position of the drainage openings 404 and grooves in the drainage layer 402 and the position of the hybrid grass support structure on the ground of the use site are chosen such that the surplus water leaving the drainage openings or grooves of the drainage layer 402 enters the pipes, channels, and/or grooves of the drainage system of the installation ground. This may be advantageous, because the water (which is expensive in many regions of the world) leaving the drainage layer 402 can be reused and because formation of puddles and the rotting of the plant roots can be prevented.

[0105] Collecting and reusing the runoff water for irrigation may not only reduce water consumption and costs, it may also prevent the leaking of fertilizer into nearby rivers and lakes. Rather, the water leaving the drainage layer openings 404 is collected and reapplied to the hybrid turf.

[0106] FIG. 5 shows a further hybrid grass support structure 500. The structure 500 and also the structure 400 depicted in FIG. 4 differ from the support structures 100, 200, and 300 in that the synthetic fibers 106 are integrated also into the upper part of the stone wool layer. This may increase the robustness of the integrated fibers against tuft withdrawal forces and hence may increase the lifetime of the hybrid turf.

[0107] FIG. 6 shows a still further hybrid grass support structure 600. The fibers are incorporated into the growth medium layer 102 and the stone wool layer 104 completely. For example, the fibers can be tufted with a tufting needle through both layers 102, 104 such that U-turned portions of the fibers are visible at the lower side of the stone wool layer 104. This provides for a particularly firm fixing of the fibers in the support structure.

[0108] FIG. 7A shows a single biodegradable, stackable box 700 according to an embodiment of the invention. The depicted box is made from biodegradable cardboard and comprises a stacking element 702 (often implemented as thickening element), at each corner that allows the stacking of multiple boxes on top of each other. Preferably, the box or its thickening elements are stiff and robust enough to allow the stacking of multiple empty as well as filled boxes, whereby a “filled box” is a box containing a piece of the hybrid turf support structure described herein for embodiments and examples of the invention.

[0109] FIG. 7B shows a stack 706 of two biodegradable boxes 700, 704.

[0110] FIG. 7C shows a hybrid turf support structure 710 formed by multiple boxes. The boxes are simply put next to each other on the ground where the hybrid turf is to be installed. The gaps between the individual boxes are for illustration only. Preferably, the boxes are arranged on the ground such that the four outer sides of the boxes are in direct contact with the sides of the neighboring boxes. This may ensure that when the biodegradable boxes have been completely degraded and the natural grass plants have formed a natural lawn, the borders of the former boxes are no longer visible. Rather, a homogeneous, hybrid grass lawn is formed.

[0111] As mentioned above, the hybrid grass structure depicted in any one of FIGS. 1-6 or parts thereof (e.g., the stone wool layer and a mat comprising the fibers) can be manufactured at a plant and transported to and installed at the use site. Alternatively, the hybrid grass support structure can be fabricated directly at the use site, e.g., by applying the stone wool layer onto the ground first and then adding the growth medium layer and the fibers. Depending on the embodiment, additional components of the support structure (seeds, fertilizers, etc.) may be added before or during installation. According to preferred embodiments, the hybrid grass support structures as depicted, for example, in FIGS. 1-6 are manufactured at a plant in the form of comparatively small pieces (“tiles”) of hybrid grass support. Each of said pieces is put into a biodegradable box, usually a stackable biodegradable box, e.g. a stackable cardboard box. The boxes with the hybrid grass support tiles are transported to the use site and installed by simply placing the boxes on the ground of the use site next to each other such that an area of box-based tiles is formed. The hybrid grass support tiles are not removed from their respective boxes for installation. Rather, the walls of the biodegradable box will degrade upon being repeatedly exposed to water.

[0112] FIG. 8A is an illustration of a single fiber 802 and a bundle 804 of synthetic fibers having been integrated into the growth medium layer 102 and the stone wool layer 104 by a tufting needle. The U-shaped loops at the upper side of the layer 102 have been cut (not shown) into two respective fiber ends extending to the upper side of the growth medium layer 102. The U-shaped loops at the lower side of the stone wool layer 104 are still visible and may form rows of tufting knots.

[0113] FIG. 8B is an illustration of a fiber-injection process that integrates a single synthetic fiber 806 into the growth medium layer 102 and the upper part of the stone wool layer 104. A comparatively short fiber is positioned on the upper surface of the growth medium layer and is pressed by a needle-like object into the layers 102, 104. When the object is pulled back out of the layers 102, 104, the free space of the injection path is filled by the surrounding material, in particular the growth medium. As a result, the injected fiber 806′ is mechanically fixed in the hybrid grass support structure.

[0114] FIG. 9 is a flowchart of a method for installing a hybrid grass support structure. The method depicted in FIG. 9 may be particularly advantageous for installing large hybrid turf structures, e.g., for a large soccer field.

[0115] First, in step 902, a layer of stone wool is applied on the ground where the hybrid turf support structure is to be installed. Thereby, a stone wool layer 104 is formed. For example, the stone wool can be provided in the form of rolls, which are unwound to form adjacent stone wool lanes. Alternatively, the stone wool can be provided in the form of tiles, which are placed on the ground such that neighboring tiles are in direct contact with each other. Preferably, the stone wool layer is applied onto ground that contains a drainage system.

[0116] Next, in step 904, the growth medium is applied on top of the stone wool layer, thereby forming the growth medium layer 102.

[0117] Next, in step 906, synthetic fibers 106 are incorporated at least into the growth medium layer 102 and optionally also into the stone wool layer 102. For example, a movable tufting machine or fiber-injection machine can be used for on-site incorporation of the fibers into the layered support structure.

[0118] In some embodiments, the fibers are applied before the growth medium. For example, a mat comprising the synthetic fibers can be placed directly on top of the stone wool layer. Then, the growth medium is added on top of the mat, whereby the added growth medium is moved and mixed with the fibers such that the fibers protrude from the growth medium and are not pressed down and covered by the growth medium.

[0119] FIG. 10 is a flowchart of an alternative method for installing a hybrid grass support structure. This method is particularly beneficial for installing support structures on small areas of only a few square meters or on areas with an irregularly shaped outline. First, in step 952, a plurality of biodegradable boxes is provided, whereby each box contains a stone wool layer, a growth medium layer, and synthetic fibers. The boxes are positioned on the ground where the hybrid turf support is to be installed such that the edges of neighboring boxes directly contact each other. Next, in step 954, the boxes are allowed to degrade. For example, the boxes are repeatedly exposed to water, e.g., actively by irrigating the boxes or passively by exposing the boxes to rain. The water and the omnipresent microorganisms will induce the biodegradation of the boxes, and the water will allow the grass seed to germinate and grow. After a couple of weeks, the tiled area with the boxes will be transformed into a homogeneous area of hybrid grass.

[0120] FIG. 11A depicts a box 700 comprising a hybrid grass support structure, e.g., the structure 600 depicted in FIG. 6. However, hybrid grass support structures according to any other embodiment of the invention may likewise be contained in the box. It is also possible that some elements of the support structure are not contained in the box when the box is delivered from the manufacturing plant to the customer at the use site. For example, the grass seed 108 may be added later by the customer, enabling the customer to freely choose the desired grass species.

[0121] FIG. 11B depicts the box 700 containing hybrid grass. The hybrid grass comprises a mixture of synthetic fibers 108 and grass blades of natural grass plants 960. When the grass plants have grown to the same height as the synthetic fibers, the walls of the box are typically already partially or completely degraded (not shown).

LIST OF REFERENCE NUMERALS

[0122] 100 hybrid grass support structure [0123] 102 growth medium layer [0124] 104 stone wool layer [0125] 106 synthetic fiber [0126] 108 grass seed [0127] 200 hybrid grass support structure [0128] 300 hybrid grass support structure [0129] 302 elastic layer [0130] 400 hybrid grass support structure [0131] 402 drainage layer [0132] 404 drainage opening [0133] 500 hybrid grass support structure [0134] 600 hybrid grass support structure [0135] 700 degradable box [0136] 702 stacking elements [0137] 704 degradable box [0138] 706 stack of two degradable boxes [0139] 710 tiled area made of multiple boxes [0140] 802 tufted single synthetic fiber [0141] 804 tufted bundle of multiple synthetic fibers [0142] 806 single synthetic fiber before injection [0143] 806′ single synthetic fiber after injection [0144] 902-906 steps [0145] 952-954 steps [0146] 960 natural grass plant