AU2008216984A1 - A Method of Preparing a Base for a Synthetic Turf and a Synthetic Turf System - Google Patents

Description

15-SEP-2008 16:11 A J PARK 64 9 3566990 Rcgulation 3-2

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AUSTRALIA

PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name of Applicant; TIGERTURF INTERNATIONAL LIMITED Actual Inventor: Christopher Allan Simpson Address for service in A J PARK, Level 11, 60 Marcus Clarke Street, Canberra ACT Australia: 2601, Australia Invention Title: A Method Of Preparing A Base For A Synthetic Turf And A Synthetic Turf System Details of Associated Provisional Application:561472 filed 13 September 2007 The following statement is a full description of this invention, including the best method of performing it known to us, COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-208 16:11 A J PARK 64 9 3566990 P.06 00 0 FIELD OF THE INVENTION cI C) The present invention relates to a method of preparing a base for synthetic turf surfaces and a synthetic turf system comprising the base. In particular, although not exdusively, the synthetic turf surfaces are for sports fields and landscaping applications.

00 BACKGROUND TO THE INVENTION 0\ Synthetic turf is a commonly used alternative to natural grass for sports playing fields, 00 10 landscaping and various other applications. Synthetic turf typically comprises a flexible O backing layer, such as a synthetic fabric, into which a synthetic yam is tufted in rows to form a pile of grass-like filaments. The pile filaments of the synthetic turf are generally teferred to in the industry as synthetic ribbons, tufts or pile elements.

Synthetic turf surfaces can be manufactured to various specifications to suit different end applications. For example, depending on the end application, the length of the pile filaments from the backing layer, known as the "pile height", the spacing between rows of pile filaments or tufts, known as the "gauge", and the synthetic materials that are utilized to form the backing layer and synthetic yarn, can all be varied or selected to suit the end application.

The installation of synthetic turf surfaces typically tequires the preparation of a base-system at the installation site onto which the synthetic turf can be laid. The base-system required often depends on the particular purpose of the synthetic turf surface and the characteristics of the landscape and ground composition at the site. Sports playing fields can be found in a variety of areas, all of which present variable quantities of material that may or may not be suitable for stable base construction. It is generally standard practice to excavate unsuitable material for removal from the site. Satisfactory material is then imported from a quarry to enable satisfactory base-system preparation works to be performed. Achieving optimum base characteristics is paramount to the longevity of the synthetic turf surface.

Figures 1 and 2 show known typical base-systems for synthetic turf surfaces. The synthetic turf surface is generally indicated by 10 and the base-system typically comprises a subgrade 2 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-200E8 16:121 A J PRRK 64 9 3566990 P.07 00 o layer 12 onto which two base-layers of granular material are formed. The lower base-layer S14 may, for example, comprise 20mmt crushed rock and the upper base-layer 16 may, for 0 example, comprise 5mm to minus crusher dust.

Preparing the base-systems shown in Figures 1 and 2 typically.involves a number of steps.

Firstly, the natural growth, such as grass, weeds and the like, is removed by scraping the 00 existing surface 20 to expose the top soil. The top soil is then removed, along with a

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u substantial quantity of subgrade soil, until clay is encountered or until a sufficient depth is reached such that the exposed subgrade layer acts as a solid platform onto which the base- 00 10 layers of rock can be installed. Typically, a minimum of 100mm of existing subgrade base 0 material must be removed in order to reach a solid platform. Once the exposed subgrade layer 12 is rolled and leveled, the lower base-layer 14 of 20rm crushed rock is installed to a thickness of approximately 120mm. Then, the upper base-layer 16 of 5nmm to minus crusher dust is installed to a thickness of approximately 20-30mmn. Installation of both the base-layers typically includes rolling and wetting the granular material to compact and level each layer as desired. Retaining walls 18 are often formed about the perimeter of the basesystem during construction as shown in Figure 1. The retaining walls may, for example, be formed from treated pine plinths or the like.

Most synthetic turf surface installations also comprise a drainage system for dealing with rainfall on the surface. These are typically either vertical or non-vertical drainage systems.

For vertical drainage systems, water penetrates through the perforated synthetic turf surface and into the base-system that may comprise a pattern, for example a herringbone pattern, of integrated drains that collect and channel the water into public drainage systems.

On a non-vertical drainage system, the synthetic turf surface is sloped such that water runs off to the side where it is collected and channeled into public drainage systems by perimeter drains, such as a concrete spoon drain 22 as shown in Figure 2.

Typically, once the base-system has been prepared and a synthetic turf surface laid, a volume of particulate material, such as sand, crumb rubber, or a combination thereof, is deposited on top of the backing layer amongst the synthetic ribbons to stabilise the synthetic turf surface, support the ribbons in a substantially upright position, and to provide desired performance characteristics that depend on the end application- The 3 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:12 A J PARK 64 9 3566990 P.08 00 0 particulate material is also known as "infill" and the thickness of the infill layer relative to the pile height can vary depending on the length of exposed ribbon above the infill required for the end application.

In this specification where reference has been made to patent specifications, other external documents, or other sources of information, this is generally for the purpose of providing a 00 context for discussing the features of the invention. Unless specifically stated otherwise, reference to such external documents is not to be construed as an admission that such documents, or such sources of information, in any jurisdiction, are prior art, or form part 00 10 of the common general knowledge in the art.

0 C It is an object of the present invention to provide an improved method of preparing a base-system for a synthetic turf surface, a synthetic turf system comprising the base-system, and/or to at least provide the public with a useful choice.

SUMMARY OF THE INVENTION In a first aspect, the present invention broadly consists in a method of preparing a basesystem for supporting a synthetic turf surface, the method comprising the steps of: preparing a subgrade layer of soil; applying a soil solidification binder to the subgrade layer that is arranged to bind the soil particles of the subgrade layer; compacting the subgrade layer after application of the binder; and allowing the applied binder to cure to form a hardened and substantially impermeable subgrade layer for directly or indirectly supporting a synthetic turf surface.

Preferably, the step of preparing the subgrade layer of soil may comprise the step of scarifying the soil, for example by ploughing, tilling, and/or grading, to expose and loosen the top soil over the surface area of the subgrade layer. Additionally, the step may comprise removing or eradicating natural growth, such as grass, weeds, plant material or the like, from the top soil then exposing the top soil. Additionally, the step may comprise 4 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-208 16:12 A J PARK 64 9 3566990 P.09 00 0 0 compacting, leveling and/or contouring of the subgrade layer after or in combination with Sscarifying.

Cj t Preferably, the step of applying the soil solidification binder to the subgrade layer may comprise the step of spraying the binder onto the surface of the subgrade layer in liquid form. The binder maybe in a powder or liquid concentrate form, and the step may 00 additionally include mixing the binder concentrate with water or another flow mixture to \O the desired concentration or dilution before application of the binder to the subgrade layer.

A higher concentration creates a harder and more substantially impermeable subgrade layer 00 10 than lower concentrations.

In one form, the soil solidification binder may be a polymer-based binder. By way of example, the polymer-based binder composition may comprise polymers, fillets, surfactants, water softeners, anti-caldng agents, starches, and colouring. It will be appreciated that any soil solidifying polymer binder could be used. Various polymer based binder compositions are known for solidifying soil. By way of example only, the binder may comprise a vinyl acrylic latex polymer or any other suitable polymer-based binding composition that is arranged to bind soil particles to form a hardened and substantially impermeable soil layer.

In another form, the soil solidification binder may be an organic-based binder.

Preferably, the thickness of the hardened and substantially impermeable subgrade layer is in the range of approximately 50mm-300mm depending on requirements.

Preferably, the step of compacting the subgrade layer after application of the binder may comprise the steps of rolling the subgrade layer with a heavy roller to compact the soil of the subgrade layer. More preferably, this step may comprise the step of further scarifying the subgrade layer after application of the binder to encourage mixing of the binder into the subgrade layer before the step of rolling is undertaken to compact the subgrade layer.

Preferably, the step of allowing the applied binder to cure comprises allowing the subgrade layer to cure under the environmental conditions for at least a predetermined time period.

COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:12 A J PARK 64 9 3566990 00 0 0 By way of example, the subgrade layer may be allowed to dry and cure for at least

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approximately 24 hours in order for the hardened and substantially impermeable subgrade C) layer to form.

Preferably, but not necessarily, the method further comprises the step of installing one or more base-layers of material on top of the hardened and substantially impermeable 00 subgrade layer. More preferably, the step of preparing the subgrade layer of soil may comprise removing soil in order to form the subgrade layer at a required depth so as to C' accommodate the one or more base-layers such that the top surface of the base-system is at 00 10 a predetermined level for supporting the synthetic turf surface.

In one form, a single base-layer of crusher dust, such as 5mm to minus grading, may be installed on top of the subgrade layer to the required depth in a manner previously described. Preferably, the thickness of the single 5mm to minus base-layer may be approximately 2 5mm but it will be appreciated that any other suitable nominal thickness could be used. In other forms, the base-layer may preferably be less than 30mt, more preferably less than 25mm, and even more preferably less than In an alternative form, a lower base-layer of crushed rock, such as 20mm grading, and an upper base-layer of crusher dust may be installed. By way of example, the thickness of the lower base-layer of 20mm crushed rock may be approximately 60mm and the thickness of the upper base-layer of crusher dust may be approximately 15mm- It will be appreciated that other thickness levels may alternatively be used. In other fonrs, the thickness of the lower base-layer of 20mm crushed rock may preferably be less than 60mm, more preferably less than 45mm, and even more preferably less than 30mm, and the thickness of the upper base-layer of crusher dust may preferably be less than 15mm, more preferably less than and even more preferably less than It will be appreciated that other combinations and compositions of base-layers of granular material may be used depending on requirements. Preferably, the step of installing one or more base-layers of material on top of the hardened and substantially impermeable subgrade layer may comprise depositing, compacting and/or leveling the or each base-layer of material in a manner known to those skilled in the art.

6 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:13 A J PARK 64 9 3566990 P.11 00 0 Preferably, the surface area of the base system is larger than the surface area of the synthetic turf surface. In alternative forms, the surface area of the base system may be substantially equal to the surface area of the synthetic turf surface.

Preferably, the method further comprises the step of installing a drainage system into the 00 base-system for a vertically draining synthetic turf surface or adjacent the base-system for a non-vertically draining surface. In one form, a drainage system, such as a herringbone C] pattern of drains, may be integrated into the one or more base-layers of the base-system for 00 10 collecting and channeling rainfall that has penetrated into the base layers from a porous 0 0 synthetic turf surface into a public drainage system. In an alternative form, a perimeter drainage system, such as a concrete spoon drain, may be installed about the perimeter of the base-system to collect water run-off from a sloped non-porous synthetic turf surface.

It will be appreciated that any other type of sub-surface or surface drainage systems, or a combination thereof, could be utilised with the base-system to collect and channel water from the synthetic turf surface and/or the base system.

Preferably, the method further comprises the step of installing a retaining wall about the perimeter of the base-system. By way of example, the retaining wall may comprise one or more plinths.

In a second aspect, the present invention broadly consists in a method of installing a synthetic turf surface having a flexible backing layer and rows of tufted synthetic ribbons representing blades of grass that extend upwardly relative to the backing layer, the method comprising the steps of: preparing a base-system fot supporting the synthetic turf surface according to any one or more aspects of the first aspect of the invention; and laying the synthetic turf surface on top of the base-system.

Preferably, the method may further comprise the step of depositing an infill layer of particulate material on top of the backing layer and amongst the synthetic ribbons to support the ribbons in a substantially upright position relative to the backing layer.

7 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-20068 16:13 A J PARK 64 9 3566990 P.12 00 O In one form, the base-system comprises a hardened and substantially impermeable Cl subgrade layer, and the step of laying the synthetic turf surface comprises hying the U) synthetic turf surface dirctly on top of the subgrade layer of the base-system.

In an alternative form, the base-system comprises a hardened and substantially impermeable subgrade layer underneath one or more base-layers, and the step of laying the 0 synthetic turf surface comprises laying the synthetic turf surface on top of the surface of 0\ the base-layer or uppermost base-layer.

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00 10 In a third aspect, the present invention broadly consists in a synthetic turf system

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o comprising: a synthetic turf surface having a flexible backing layer and rows of tufted synthetic ribbons representing blades of grass extending upwardly from the backing layer; and a base-system supporting the synthetic turf surface, the base-system comprising at least a hardened and substantially impermeable subgrade layer comprising a mixture of soil and a soil solidification binder.

In one form, the soil solidification binder is a polymer-based binder. In an alternative form, the soil solidification binder is an organic-based binder.

Preferably, the base-system may further comprise one or more base-layers on top of the subgrade layer as defined in respect of the first and second aspects of the invention.

Preferably, the synthetic turf system may further comprise an infill layer of particulate material on top of the backing layer of the synthetic turf surface and amongst the synthetic nbbons to support the ribbons in a substantially upright position relative to the backing layer.

The third aspect of the invention may comprise any one or more features that are a result of the methods defined in respect of the first and second aspects of the invention.

8 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:13 A J PARK 64 9 3566990 P.13 00 0 Unless the context suggests otherwise, the term "soil" as used in this specification and claims is intended to cover dirt, gravel, stones, sand, dust, rocks, clay or any combination 0) thereof.

t¢) The term "comprising" as used in this specification and claims means "consisting at least in part of'. When interpreting each statement in this specification and claims that includes 00 the term "comprising", features other than that or those prefaced by the term may also be Spresent. Related terms such as "comprise" and "comprises" are to be interpreted in the Ssame manner.

00 0 O The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

BRIEF DESCRIPTION OF THE DRAWINGS Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which: Figure 1 is a cross-sectional view of a known synthetic turf system in which the basesystem is surrounded by soil; Figure 2 is a cross-sectional view of a known synthetic turf system in which the basesystem has a concrete spoon drainage system about its perimeter; and Figure 3 is a cross-sectional view of one preferred embodiment synthetic turf system of the invention in which the base-system comprises a hardened and substantially impermeable subgrade layer and a single base-layer of crusher dust.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The invention relates to a method of preparing and providing a base-system for supporting a synthetic turf surface. The base-system preferably comprises at least a subgrade layer of 9 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-200E8 16:14 A J PARK 64 9 3566990 P.14 00 O0 o soil that is hardened and substantially impermeable via the application of a soil C" solidification binder. The subgrade layer may directly abut and support the synthetic turf 1) surface or alternatively one or more base-layers of material may be formed on top of the subgrade layer. When the base-system comprises one or more base-layers, the surface of S 5 the uppermost base-layer is arranged to abut the backing layer of the synthetic turf surface.

It will be appreciated that various combinations of base-layers may be formed on the subgrade layer, and the or each base-layer may comprise particular gradings of granular 00 C material, such as crushed rock, crusher dust, or other suitable material known to those Sskilled in the art of synthetic turf installation.

00 o Referring to figure 3, the preferred form based-system comprises a lower subgrade layer and an upper base-layer 32 onto which the synthetic turf surface 34 is installed. Preferably, the base-system may comprise a retaining wall 34, formed by wood plinths or the like, to separate the base-system from the adjacent indigenous soil 36 at the installation site.

In the preferred form, the subgrade layer 30 comprises indigenous soil to which a soil solidification binder has been applied and allowed to cure to form a hardened and substantially impermeable subgrade layer. By way of example, the subgrade layer may have a thickness in the range of approximately 50-300mm for sports field applications, such as football, rugby or the like, but this thickness maybe altered depending on the synthetic turf surface characteristics and end application. The base-layer 32 of the base-system preferably comprises granular material such as 5mm to minus crusher dust and may have a thickness in the range of approximately 2 0-30mm for sports field applications, such as football, rugby or the like, but this thickness may also be altered and the base-system may also incorporate a larger stone crushed layer underneath. The thickness of this will vary depending on the thickness of the subgtade soil layer.

Preparation of the base-system will now be explained for the preferred form synthetic turf system shown in figure 3. Firstly, the method for preparing the base-system comprises preparing the subgrade layer 30. This involves preparing the indigenous soil at the installation site by scarifying to expose and loosen the top soil. The surface area of the subgrade layer is preferably larger than the area of the synthetic turf surface, although it may be substantially equal depending on the end application of the synthetic turf.

COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:14 A J PARK 64 9 3566990 00 O0 o Preparation of the soil may include a combination of various techniques that depend on C, the particular characteristics of the soil at the installation site. Typically, preparing the soil 1) involves firstly removing any natural growth and exposing the top soil- The top soil is then scarified, for example by ploughing, tilling, rotary hoeing or grading in order to loosen or expose the top soil. The soil may be scarified to a desired depth depending on requirements but this may typically be in the range of 50-3 0 0mm for sports field 0 applications. If additional soil is required from external sources, this maybe added at this 00 01 time. The scarified top soil is then preferably contoured and levelled as required and ideally

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the top soil comprises at least some portion of clay but this is not essential.

00 SNext, a soil solidification binder is applied to the scarified top soil. Preferably, die binder is sprayed onto the surface by a watering truck or tanker or using any other suitable application method to apply the binder to the soil. In the preferred form, the binder is applied in liquid form.

Once the binder has been applied, the soil is preferably scarified again to mix the binder into the soil. The scarified soil is then preferably rolled and levelled until the approximate required level and contour has been achieved. The soil is then preferably compacted using a weighted roller or the like to facilitate bonding of the binder to the soil particles and each other. In the preferted form, the compaction may include a combination of rolling and vibrating the soil. The depth into the soil that the binder soaks depending on the volume and concentration of the binder applied, and these can be varied as desired to produce the required subgrade layer characteristics, such as hardness, impermeability, thickness and the like. It will also be appreciated that the spraying device or truck may be arranged to spray the binder at a predetermined flow rate taking into account the moisture content in the soil.

The soil and applied binder is then allowed to dry and cure for a suitable time to allow the binder to bind the soil particles into a hardened and substantially impermeable subgrade layer 30. In the preferred form, the curing time may be at least 24hours but this may depend on the environmental conditions and the volume of binder applied to the soil.

After the subgrade layer 30 has cured, the base-layer 32 of granular material, such as to minus crusher dust, is installed. This base-layet is installed, compacted and leveled in a 1I COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:14 A J PARK 64 9 3566990 P.16 00 0 0 manner known to those skilled in the art. It will be appreciated that alternative forms of the Sbase-system may comprise one or more base-layers comprising various gradings of crushed Srock or other material as desired depending on synthetic turf surface and its end Vi' applications.

Once the base-layer 32 is installed, the synthetic turf surface 34 can be laid on the upper OO surface of the base-layer in a manner known to those skilled in the art. This may or may \0 not also involve the installation of an infill into the synthetic turf surface depending on the Send application and purpose of the synthetic turf surface. In alternative forms, the base- 00 10 system may only comprise the subgrade layer 30 without any additional base-layers. In 0 these forms, the synthetic turf surface may be laid directly on top of the subgrade layer It will be appreciated that the synthetic turf surfaces are of type previously described and may be for sports fields, landscaping or other applications. It will also be appreciated that the base-system may be sloped or contoured to suit different landscapes and applications for the synthetic turf surfaces. The base-system need not necessarily be flat.

Drainage systems for rainfall may also be integrated into the base-system for vertically draining porous synthetic turf surfaces or adjacent the base-system for a non-vertically draining surface. For example, Figure 3 shows a vertically draining surface in which the rain will travel through the porous synthetic turf surface 34 and then meet the impervious subgrade layer 30 that is arranged to channel the water to the perimeter of the base-system for disposal into a public drainage system. Depending on requirements, it will be appreciated that various types of drainage systems may be integrated into the base-layer(s) of the base-system or about the perimeter of the base-system. The drainage systems may, for example, be complex herringbone pattern drains, or alternatively relatively inexpensive perimeter concrete spoon drains or the like. For a non-vertically draining surface, the water from rainfall travel across the top of the appropriately sloped synthetic turf surface 34 and to some form of perimeter drainage system.

The soil solidification binder is designed to solidify and harden the soil particles of the subgrade layer by binding the soil particles together. In one preferred form, the soil solidification binder is a polymer-based binder. Various polymers may be used in the 12 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:15 A J PARK 64 9 3566990 P.17 00 0 0 binder composition and these are known to these skilled in the art of soil solidification polymer-based binders. By way of example, the polymer-based binder may comprise a composition of polymers, fillers, surfactants, water softeners, ant-caking agents, starches t and colorings. By way of example, one type of polymer that may be used is a vinyl actylic latex polymer.

00 In operation, the polymer-based binder coats the grains and particles of the subgrade soil \O material to reduce permeability, maintain dry strength and higher material density and to C provide improved stabilization properties by the polymeric binding of fine particles with O0 10 larger particles of the soil of the subgrade. In particular, the binder composition causes O dilation and rapid densification of soil particles under the vibratory compacting process.

Preferably, the binder has water-repelling properties and will reconstitute itself when in contact with water. In the preferred form, the binder is non-toxic.

In an alternative preferred form, the soil solidification binder may be an organic-based binder. Various organic soil solidification binding compositions are known to those skilled in the art of soil solidification. By way of example, such organic compositions may comprise an aqueous emulsion of blended material, being for example, organic esters and acid salts. It will be appreciated that various water-based organic emulsion binders could be used.

The binder composition is typically in a powder or liquid concentrate form and may be mixed with water or some other flow mixture at the installation site to enable the binder to be applied to the soil by spraying, dabbing, rolling or the like. At higher concentrations of the binder, the soil particles are bonded such that they form a substantially impermeable hardened subgrade layer that is substantially water-tight. Lower concentrations of the binder can also be used by substantially diluting the concentration to provide a less hardened and impermeable subgrade layer, if desired. The concentration of the applied binder determines the degree of hardness and impermeability of the subgrade layer.

The subgrade layer 30 of the base-system forms a solid platform onto which the synthetic turf surface can be supported either directly or indirectly by one or more additional baselayers. Compared to existing base-systems, the use of the soil solidification binder on the 13 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:15 A J PARK 64 9 3566990 P.18 00

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0 soil enables a solid platform for the base-system to be created at a relatively shallow depth.

In particular, the use of the binder enables a solid platform subgrade layer to be formed without the need of removing a substantial quantity of soil from the installation site until a V solid platform of natural subgrade material is located at a deep depth. Using the binder to create a hardened subgrade layer at a shallower depth reduces the amount of materials, time and labour involved in preparing the base-system for synthetic turf installations.

00 C The foregoing description of the invention includes preferred forms thereof. Modifications Smay be made thereto without departing from the scope of the invention as defined by the 00 10 accompanying claims.

14 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15

Claims (6)

15-SEP-2008 16:15 A J PRRK 64 9 3566990 P.19 00 o WHAT WE CLAIM IS: 1) 1. A method of preparing a base-system for supporting a synthetic turf surface, the method comprising the steps of: preparing a subgrade layer of soil; applying a soil solidification binder to the subgrade layer that is 0 arranged to bind the soil particles of the subgrade layer; O compacting the subgrade layer after application of the binder; and allowing the applied binder to cure to form a hardened and substantially 00 impermeable subgrade layer for directly or indirectly supporting a synthetic 0 turf surface. 2. A method according to claim 1 wherein step comprises scarifying the soil. 3. A method according to claim 2 wherein step comprises compacting and levelling the subgrade layer after scarifying the soil. 4. A method according to any one of the preceding claims wherein step comprises eradicating natural growth from the soil. A method according to any one of the preceding claims wherein step comprises spraying the binder onto the surface of the subgrade layer in a liquid form. 6. A method according to any one of the preceding claims wherein the soil solidification binder is a polymer-based binder that is arranged to bind the soil particles of the subgrade layer to form a hardened and substantially impermeable soil layer. 7. A method according to any one of claims 1-5 wherein the soil solidification binder is an organic-based binder that is arranged to bind the soil particles of the subgrade layer to form a hardened and substantially impermeable soil layer. 8. A method according to any one of the preceding claims wherein step comprises rolling the subgrade layer to compact the soil of the subgrade layer. COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-200e 16:15 A J PARK 64 9 3566990 00 O 9 A method according to claim 8 wherein step further comprises scarifying the 2 subgrade layer after application of the binder to encourage mixing of the binder into the subgrade layer before rolling is undertaken to compact the subgrade layer. 10. A method according to any one of the preceding claims wherein step comprises allowing the subgtade layer to cure under environmental conditions for at least a Spredetermined time period. 00 sO 11. A method according to any one of the preceding claims further comprising the step of installing one or more base-layers of material on top of the hardened and 00 0 substantially impermeable subgrade layer after curing of the binder. 0 12. A method according to claim 11 wherein step comprises removing soil in order to form the subgrade layer at a required depth so as to accommodate the one or more base-layers such that the top surface of the base-system is at a predetermined level for supporting the synthetic turf surface. 13. A method according to any one of the preceding claims further comprising the step of installing a drainage system into the base-system for a vertically draining synthetic turf surface. 14. A method according to any one of claims 1-12 further comprising the step of installing a drainage system adjacent the base-system for a non-verdcally draining synthetic turf surface. A method according to any one of the preceding claims further comprising the step of installing a retaining wall about the perimeter of the base-system.

16. A method of installing a synthetic turf surface having a flexible backing layer and rows of tufted synthetic ribbons representing blades of grass that extend upwardly relative to the backing layer, the method comprising the steps of: preparing a base-system for supporting die synthetic turf surface comprising the steps of: i) preparing a subgrade layer of soil; ii) applying a soil solidification binder to the subgrade layer that is arranged to bind the soil particles of the subgrade layer; 16 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-20018 16:16 A J PARK 64 9 3566990 P.21 00 O0 iii) compacting the subgrade layer after application of the binder; and C' iv) allowing the applied binder to cure to form a hardened and U) substantially impermeable subgrade layer for directly or indirectly supporting a synthetic turf surface; and laying the synthetic turf surface on top of the base-system.

17. A method according to claim 16 wherein step comprises laying the synthetic 00 turf surface directly on top of the hardened and substantially impermeable subgrade NO layer of the base-system. 00 18. A method according to claim 16 wherein step further comprises installing one 0 or more base-layers of material on top of the hardened and substantially impermeable subgrade layer after curing of the binder, and step comprises laying the synthetic turf surface on top of the surface of the base-layer or upper most base-layer.

19. A synthetic turf system comprising: a synthetic turf surface having a flexible backing layer and rows of tufted synthetic ribbons representing blades of grass extending upwardly from the backing layer; and a base-system supporting the synthetic turf surface, the base- system comprising at least a hardened and substantially impermeable subgrade layer comprising a mixture of soil and a soil solidification binder. A synthetic turf system according to claim 19 wherein the base-system comprises one or more base-layers of material on top of the subgrade layer.

21. A method of preparing a base-system for supporting a synthetic turf surface according to claim 1 and substantially as herein described with reference to any embodiment disclosed.

22. A method of preparing a base-system for supporting a synthetic turf surface substantially as herein described with reference to Figure 3. 17 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15 15-SEP-2008 16:16 A J PARK 64 9 3566990 P.22 00 0 O 23. A method of installing a synthetic turf surface according to claim 16 and C] substantially as herein described with reference to any embodiment disclosed. C) V/ 24. A method of installing a synthetic turf surface substantially as herein described with Sreference to Figure 3. A synthetic turf system according to claim 19 and substantially as herein described 00 with reference to any embodiment disclosed. 0\ NO S26. A synthetic turf system substantially as herein described with teference to Figure 3. CO 00 0 18 COMS ID No: ARCS-206147 Received by IP Australia: Time 14:17 Date 2008-09-15