EP4619584A1

EP4619584A1 - Surface structure including a mesh and method of forming the same

Info

Publication number: EP4619584A1
Application number: EP25708834.4A
Authority: EP
Inventors: Sean Scott
Original assignee: Vuba Chemical Innovations Ltd
Current assignee: Vuba Chemical Innovations Ltd
Priority date: 2024-01-31
Filing date: 2025-01-31
Publication date: 2025-09-24
Also published as: GB202501418D0; GB202401266D0; WO2025163328A1

Abstract

A surface structure to form an area of hard-standing and method of forming the same, comprising at least a first mesh and typically a ballast material, and possibly a second or further mesh layer, and a particulate body formed by a particulate material bound by a resin acting as an external surface for the surface structure. The mesh layers act to reinforce the relatively unitary structure, reducing damage to the particulate body that may otherwise be subject to crack propagation.

Description

Surface structure including a mesh and method of forming the same

The invention to which this application relates is to the provision of a surface structure, and method of forming the same, for use in an area of hard standing in particular, but not necessarily exclusively, for use in driveways, pathways, outdoor areas and the like. The surface structure is conventionally comprised of a particulate, located on a support surface and bound together with a resin. The particulate material may be gravel and/ or stones and, in particular, although not necessarily exclusively, relatively small stone or gravel particles commonly referred to as chippings, gravel or the like and hereby referred to in a non-limiting manner as particulate material. The particulate material can be, for example, provided in different colours for different areas or zones so as to provide an aesthetically appealing surface as well as providing added permanence to the surface which is formed and to provide hardwearing characteristics in comparison to, for example, a surface of grass, soil or the like or loose particulate material which is susceptible to movement due, for example, rainwater flowing across the same, puddles and/or differences in levels of wear on different part of the surface by persons.

It is known to provide a resin bound layer of particulate material for an area of hard standing. The resin is typically provided as two separate components which, when combined, begin to cure. The two resin components are combined with the particulate material and a binding quartz material by a forced-action mixer to ensure the particulate material is coated in the resin. Before the resin has cured, the particulate material is distributed about a surface and levelled by the installer. Once the resin has cured, the individual particulates are bound to each other so as to form a substantially unitary body of particulate and cured resin. This provides the advantage that the particulate body is stabilised when load is applied, and that there is a reduced likelihood that particulates will be removed from the location the body is located.

However, the conventional unitary body which is formed can be susceptible to damage over time especially if the support surface onto which the same has been applied moves, cracks or is generally uneven and/ or unstable. A base can be formed on the support surface by digging down, and a foundation laid but it will be appreciated that this laying of foundation or replacement of foundation is a labour- intensive task and can result in material waste when unsuitable preexisting foundation is removed.

The lack of a suitable base for the unitary body may result in damage to the same. For example, if the unitary body is laid on a damaged existing surface, such as cracked concrete or tarmac, cracks that form in the support surface may propagate through the unitary particulate body. This problem is exacerbated if the unitary body is at least partially bound to the underlying surface.

Also, if there is no underlying foundation, and the unitary body is laid direcdy on grass, soil, or other forms of unworked earth, a point load applied to the unitary body will be unsupported and put the unitary body into bending, forming cracks in the same.

Furthermore, an underlying foundation without adequate water drainage can allow water to be trapped between the foundation and the unitary body, which may affect the adhesion of the resin or form cracks in the body if the water freezes and expands.

An aim of the present invention is therefore to provide a surface structure for an area of hard standing that will minimise crack propagation from an underlying surface through the same.

A further aim of the invention is to provide a surface structure for an area of hard standing that is reinforced such that the material may be laid without a foundation.

A yet further aim of the invention is to provide a surface structure for an area of hard standing that is suitably permeable to water, such that water does not build up in contact with the body and damage the same.

In a first aspect of the invention, there is provided a surface structure to form an area of hard standing, the surface structure including a particulate body comprising a plurality of particulates and a resin material which, when cured, acts to at least partially bond the particulates and form said particulate body and wherein the surface structure further includes at least one mesh layer located intermediate the particulate body and a support surface in use

In one embodiment the said mesh layer is bound with the particulate body by the said resin when applied thereto to form an integral part of the said surface structure.

In one embodiment the particulate body, and at least one mesh layer form a unitary body.

Typically the resin material includes a binding quartz material. Preferably the binding quartz material is translucent and has a reduced absorbency to the particulate material.

In one embodiment the mesh layer has a thickness such that the particulate body located on a first side of the mesh is held at a distance above a support surface on which the mesh is located in use. This provides the advantage that cracks that may form do not propagate into and through the surface structure as it is located separate and/ or above the same.

In one embodiment the mesh layer has a thickness such that the particulate body is reinforced by the mesh layer.

In one embodiment the mesh which is used is a Structural Reinforcement Mesh (SRM). In one embodiment the mesh includes knitted synthetic yarns and black PVC material.

In one embodiment at least first and second, spaced apart mesh layers are provided as part of the surface structure.

In one embodiment the said first and second mesh layers are spaced apart by a ballast material of a predetermined depth. In one embodiment the size of the ballast particles and/ or depth of the ballast layer may be dependent upon the particular subsequent use and/ or wearing characteristics of the surface structure that is formed and/ or the size of the particulate to form the top layer of the support surface which is used.

In one embodiment the ballast material may be mixed with a resin which cures after duration of time of being exposed to the environment.

In one embodiment the resin mixed with the ballast material is the same as that which is mixed with the particulate material.

Typically the first mesh layer is located on the support surface as the bottom layer of the surface structure, followed by the ballast layer, followed by the second mesh layer and then the particulate body of resin and particulates which forms an external face of the surface structure, and hence area of hardstanding when formed.

In one embodiment the particulate material is gravel.

In one embodiment the resin is mixed in a forced action mixer with the particulate material and/ or the ballast is mixed with resin in a forced action mixer at the location at which the surface structure is to be formed.

In one embodiment, the resin is provided as a 2-part resin that begins to cure when the two components of the resin are mixed together.

In a further aspect of the invention, there is provided a method of forming a surface structure to form an area of hard- standing, wherein said method comprising the steps of: placing a first mesh layer in position onto a support surface of the area on which the hardstanding is to be provided, placing a mesh layer across the surface area and applying a layer of particulate material mixed with a resin onto the said mesh layer so as to bind with the mesh layer such that when the resin cures and hardens a substantially unitary surface structure is formed. In one embodiment the method includes the step of distributing a ballast material across the said mesh layer placed onto the support surface to a predetermined depth and then applying said layer of particulate material mixed with said resin to form the surface structure.

In one embodiment when the said ballast material has been applied a second mesh layer is placed onto the layer of ballast material and said layer of particulate material mixed with said resin is applied onto said second mesh layer and ballast such that when the resin cures said substantially unitary surface structure is formed.

Typically the second mesh layer is substantially enclosed within the said surface structure once formed.

In one embodiment a resin is mixed in a forced action mixer with the ballast material prior to the application of the same and a resin is mixed with the particulate material in a forced action mixer prior to application of the same.

In one embodiment the resin used is the same for both the ballast and particulate materials. Although different resins may be used for different purposes.

In one embodiment, the resin is a 2-part resin that begins to cure when the two components of the resin are mixed together.

Thus, there is provided a surface structure that is comprised of a particulate material located with a mesh layer, the particulates bonded with each other and/ or with the mesh by a resin.

Typically the mesh layers used are structural reinforcement mesh (SRM) layers. This enables an installer to install the mesh layers relatively easily on the support surface on which the particulate is to be located and apply the ballast and particulate material layers in sequence. The mesh layers act to reinforce the surface structure of particulate material and/ or separate the same from the base. This reduces damage to the particulate body that may otherwise be subject to crack propagation. It requires little or no work to be carried out on the foundation or support surface and, in some embodiments, the mesh layer may replace the need for a foundation or support surface.

In one embodiment third or more layers of mesh may be used to build up the support surface.

Specific embodiments of the invention will now be described with reference to the following figures, wherein:

Figure la illustrates a plan view of an area of hard standing formed in accordance with the invention;

Figure lb illustrates a sectional side view along line AA of the surface structure of the area of hard standing of Figure la formed in accordance with one embodiment of the invention;

Figure 1c illustrates the cross sectional side view of the surface structure of Figure lb once cured;

Figure Id illustrates a sectional side view along line AA of the surface structure of the area of hard standing of Figure la formed in accordance with a second embodiment of the invention;

Figure 2 illustrates a sample of a mesh layer used in the invention in one embodiment; and

Figure 3 illustrates an underside view of part of a unitary surface structure formed in accordance with the embodiment shown in Figure 1c.

Referring firstly to Figure la, there is illustrated a plan view of, in this embodiment a domestic premises front garden with trees and flower beds 1 and a driveway 3 leading from pavement 5 and road 7 to a garage 9 of the premises and along which driveway 3 vehicles, persons and garden implements such as wheelbarrows, mowers and the like are required to pass. In order to allow the driveway to withstand the pressure of this passage and provide a surface which is stronger and more reliable, the driveway is conventionally formed by removing top soil to form a support surface or sub base 4 and then forming an area of hard standing, using gravel, concrete, tarmac or the like but each of these surfaces has disadvantages. It is also known to bond the gravel but this can be prone to cracking and disintegration over time. Thus in Figure la the driveway is formed as an area of hard standing 3 using a surface structure formed in accordance with the invention. It should be appreciated that the uses of this invention may extend to advantage in the formation of any area of hard standing using gravel which is bound together.

Figure lb illustrates a first embodiment of the surface structure 2 of the invention used to form the area of hard standing 3. Figure lb illustrates a cross sectional view of part of the surface structure 2 of the area of hard standing 3 along line AA of Figure la, with the surface structure 3 located on a sub-base or support surface 4 formed in a conventional manner.

The surface structure 2 is comprised of a number of layers which, in this embodiment comprise a first structural reinforcement mesh (SRM) layer 6 laid onto the support surface 4.

The support surface 4, or sub-base, is formed of an aggregate that is compacted to form a level surface for the mesh layer to be placed thereon. The support surface 4 can be formed of crushed stone, with an average diameter of between 40mm-75mm but other aggregates diameters may be suitable depending on the expected traffic type on the surface structure. As is common in the art, the aggregate is formed of any of crushed granite, limestone, gritstone and/ or basalt.

The support surface 4 is chosen to comply with the relevant regulations for loadbearing sub-bases. In this example, the support surface is MOT Type 3 compliant, meaning that the average aggregate diameter is less than 75mm. This support surface is suitable for areas with pedestrian or light vehicle traffic. In an alternative example, the support surface can be MOT Type 1 compliant, meaning that the average diameter is less than 40mm. In this example, the support surface is suitable for greater vehicle traffic, such as car parks etc, as the smaller diameter size increases the surface area of the aggregate particles and increases the stability of the same when a load is applied. In either case, the depth of the support surface 4 is typically at least 225mm deep. In alternative examples, and depending on the quality of the foundation on which the support surface 4 is applied, the depth may be less than or greater than 225 mm. For example, if the foundation is loose soil, the support surface will need to be deeper than 225 mm to provide greater stability to the structure. If the foundation is a preexisting base, such as concrete, the support surface may not need to be as deep as 225 mm. This provides the advantage that no digging is required to provide a suitable foundation for the support surface 4, as the depth of the support surface can be varied depending on the quality of the existing foundation.

When applying the support surface 4 to the foundation, an initial layer of aggregate material is laid, flattened, and compressed by common machinery such as a plate compacter. The next layer is then applied onto this initial layer, flattened and compressed again. The support surface 4 is therefore formed by multiple layers, and this provides the advantage that the support surface is uniformly compressed throughout its depth.

Throughout its depth, the support surface may be seeded with granolithic particles (not shown), commonly referred to as grano dust. The grano dust, with an average diameter less than 6 mm, smooths the surface of the support surface 4, and ensures the same is flat for the application of the mesh layer 6.

The mesh layer 6, which may be of the form shown in more detail in Figure 2, is configured in a knitted grid structure formed by intersecting strands 8. The strands 8 in this embodiment are formed of high-tenacity multifilament polyester yarns that are coated with black PVC, which provides UV resistance and increased durability to the mesh. The mesh layer in this embodiment is 1 mm thick although other thicknesses may be utilised to meet specific on-site installation and/ or subsequent use requirements. The mesh layer 6 is typically initially provided in a roll, such that an installer can readily roll the layer 6 directly on to the support surface 4 to the required length. The intersecting strands 8 can be readily cut by handheld cutting implements, such as wire cutters, and as such the SRM layer 6 can be laid on a support surface 4 and up to the boundary profile 11 of the area of hard standing 3.

Applied onto the first mesh layer 6 is a ballast material 10 which is coated in a binding resin prior to the application of the same to be spread across the first SRM mesh layer 6. This ballast material 10 is provided of a size and/or thickness suitable for the particular purpose of the area of hard standing and / or size of the particulate material to be used. The ballast material 10 in this embodiment is a urethane binder course, and is laid to a depth of 30 mm. In this example, the ballast layer 10 is formed of recycled materials from railway ballast, also referred to as track ballast. The ballast layer distributes force applied to the surface structure 2 downwards to the support surface 4, and is permeable to water, which prevents water pooling on the structure 2. Typically the intersecting strands 8 of the mesh layer 6 are spaced sufficiently to allow particles of the ballast material layer 10 to partially be located between the strands 8 when the ballast material layer 10 is laid onto the mesh layer 6. This ensures that the ballast layer 10 is able to be bound with the mesh layer 6 via the resin which with the ballast material is mixed so as to form the mesh layer 6 as an integral part of the ballast material layer 10, as illustrated in Figures 1c and 3. Furthermore, the ballast material in some embodiments is bound with the support surface layer 4, further stabilising the structure 2.

The resin used to bind the ballast material 10 may be provided as a two-part resin, such that mixing the two parts or components triggers the curing of the same. To prepare the layer 10, the ballast material is combined with the coating resin in a forced action mixer. An installer then uses a spazzle tool to ensure the layer 10 is spread evenly to a required depth on the support surface 4 and then flattened using a roller. Typical machine compressors, such as the plate compressor used to compress the support surface layer 4, are unsuitable to flatten the ballast layer 10, as it has been coated in a binding resin, which would likely coat the machinery. Instead, a wet pour roller is used to flatten the surface of the layer 10.

The ballast material 10 further acts as a suitable level foundation for a second mesh layer 12 to be laid thereon. The second SRM layer 12 in this embodiment is of a similar construction to the first SRM layer 6 and is typically placed on to the ballast layer 10 once the binding resin of the same has cured. This second mesh layer 12 acts to form a foundation for a particulate body 14 to be formed thereon.

The particulate body 14 is the top surface of the surface structure 2 and includes particulates mixed with a resin which cures and hardens. Typically the particulates are of a form and/ or colour which are selected to provide a particular aesthetic effect for the external appearance of the area of hard standing. In this example, the particulate body 14 is formed of fragments of marble that are naturally coloured to suit the aesthetic requirements of the user. In other examples, the particles of the particulate body 14 are dyed. The particulate body in this example is 24mm deep, and the particles 16 of the body have an average diameter of 10mm. In other examples, the particulate body is at least 15mm deep for pedestrian traffic, 18mm for vehicle traffic, and 21mm for heavy vehicle traffic.

In this example, the particulate body 14 has been mixed by a forced-action mixer which mixes the selected particulates with a binding resin. In this embodiment the resin is a two-part resin similar to that used for the ballast material layer 10 but in one embodiment, with the addition of a binding quartz formed of 0.4-0.8mm particles of quartz material. This binding quartz provides a translucent, matte appearance to the particulate body 14 and strengthens the same.

The mixing of the two parts of the resin triggers the commencement of the curing of the resin but allows the same to be sufficiently fluid for a sufficient period of time to allow the same to be laid before the same completely cures and hardens to form the particulate body.

The particulate body mixture is then applied onto the mesh layer 12, as illustrated in Figure lb. The particulate body is laid using a spazzle or sledge, and is flattened using a hand trowel or roller, similar to the ballast material layer 10 before the resin fully cures. When the resin has cured, an exterior surface 18 is formed that is permeable to water and load can be applied thereto. Before the resin has cured, some of the particles 16 and resin of the particulate body partially fall through the gaps in the mesh layer 12 into to the ballast material layer 10. When the resin has cured, the particulate body layer 14 forms a unitary body with the second mesh layer 12 through which it partially extends and the ballast layer 10 thereunder, as illustrated in the cross-section view of Figure 1c. This is similar to the ballast and resin of the ballast layer 10 partially extending through the first mesh layer 6. This extending through the relevant interfaces enhances the bond between the layers and the particles and ballast of the respective layers, increasing the strength and stability of the unitary body.

It has been found through testing that the strength of the surface structure 2 of the embodiment illustrated in Figure 1c is significandy greater, such as 57% greater than an asphalt road surface under the same load conditions. The unitary form of the surface structure is also illustrated in Figure 3 which is a removed part 13 of the area of hard standing shown in Figure la.

Figure Id illustrates an alternative embodiment of the surface structure in accordance with the invention which may be used for surface structures which, for example, have reduced or less heavy traffic over the same. The same reference numerals are used where relevant but in this case only one SRM layer, layer 12 is used and this is located at the interface between the particulate body layer 14 and the ballast material layer 10.

The provision of the first 6 and second 12 mesh layers or single mesh layer 12 act as a means to strengthen and bond the ballast and particulate layers 10, 14 that have been formed thereon and bound with the same by binding resin, whilst acting as a level foundation for the same.

Examples of the surface structures formed in accordance with the invention include are, in order from the sub base to the external surface:

1) 6mm Blend surface structure

Subbase Surface structure comprising:

SRM first mesh layer as the bottom layer

28mm Ballast

SRM second mesh layer

18mm of 6mm blend Resin Bound top layer and external surface.

2) 10mm Blend surface structure

Subbase

Surface structure comprising:

SRM first mesh layer as the bottom layer

22mm Ballast

SRM second mesh layer

24mm of 10mm blend Resin Bound top layer and external surface.

The provision of this type of surface structure allows for the particulate or resin bound body layer 14 to be bonded to the support surface 4 whilst adding strength in all directions. In addition, the use of the ballast layer 10 adds greater depth and durability to the surface structure build up.

There is therefore no need to replace an existing base if it is cracked or damaged, and there is no need to lay an initial base if there is none in place, in these embodiments of the invention. This provides an environmental benefit, reducing the work needing to be carried out and the cost of associate waste materials.

The particles of the ballast material, particulate body and/ or the support surface partially extend between the grid structures of the SRM layers, and bind with the same, ensuring the uniformity of the structure 2 through strengthened bonding.

Claims

1. A surface structure to form an area of hard standing, the surface structure including a particulate body comprising a plurality of particulates and a resin material which, when cured, acts to at least partially bond the particulates and form said particulate body and wherein the surface structure further includes at least one mesh layer located intermediate the particulate body and a support surface in use.

2. A surface structure according to claim 1, wherein the said at least one mesh layer is bound with the particulate body by the said resin to form an integral surface structure therewith, such that the resin, particulates and at least one mesh layer form a unitary body.

3. A surface structure according to any preceding claim, wherein the resin material includes a binding quartz material that is translucent and has a reduced absorbency relative to the particulate material.

4. A surface structure according to any preceding claim, wherein the at least one mesh layer has a thickness such that the particulate body located on a first side of the mesh layer is reinforced by the mesh layer and held at a distance above a support surface on which the mesh layer is located in use.

5. A surface structure according to any preceding claim, wherein the at least one mesh layer is comprised of a structural reinforcement mesh (SRM) including knitted synthetic yarns.

6. A surface structure according to any preceding claim, wherein the structure includes at least first and second spaced apart mesh layers.

7. A surface structure according to claim 6, wherein the said first and second layers are spaced apart by a ballast material of a predetermined depth.

8. A surface structure according to claim 7, wherein the ballast material is formed of ballast particles, and the size of the ballast particles and/ or depth of the ballast layer is dependent upon the particular subsequent use and/ or wearing characteristics of the surface structure that is formed and/ or the size of the particulates necessary to form the top layer of the surface structure which is used.

9. A surface structure according to any of claims 7-8, wherein the surface structure is formed by a first mesh layer as the bottom layer in contact with a support surface in use, a ballast layer, a second mesh layer, and a bound particulate top layer which acts as an external facing surface of the surface structure when formed.

10. A surface structure according to any of claims 7-9, wherein the particulate material and/ or ballast is mixed with resin in a forced action mixer.

11. A surface structure according to any preceding claim, wherein the particulate material is or includes gravel.

12. An area of hard standing formed using a surface structure as defined in any of claims 1-11.

13. A method of forming a surface structure to form an area of hard- standing, wherein said method comprising the steps of: placing a first mesh layer in position onto a support surface of the area on which the hardstanding is to be provided, placing a mesh layer across the surface area and applying a layer of particulate material mixed with a resin onto the said mesh layer so as to bind with the mesh layer such that when the resin cures and hardens a substantially unitary surface structure is formed.

14. A method according to claim 13 wherein the method includes the step of distributing a ballast material across the said mesh layer placed onto the support surface to a predetermined depth and then applying said layer of particulate material mixed with said resin to form the surface structure.

15. A method according to claim 14 wherein once the said ballast material has been applied a second mesh layer is placed onto the layer of ballast material and said layer of particulate material mixed with said resin is applied onto said second mesh layer and ballast such that when the resin cures said substantially unitary surface structure is formed.

16. A method according to any of claims 13-14, wherein the mesh layers are structural reinforcement mesh (SRM) layers.

17. A method according to any of claims 13-16 wherein third or more mesh layers are used to build up the surface structure.