WO2021229573A1

WO2021229573A1 - Synthetic binder for repairing potholes, apparatus and method of making the same

Info

Publication number: WO2021229573A1
Application number: PCT/IL2021/050543
Authority: WO
Inventors: Ronen YOGEV; Shmuel Kenig
Original assignee: Road Code Engineering Ltd.
Priority date: 2020-05-12
Filing date: 2021-05-12
Publication date: 2021-11-18
Also published as: GB202006990D0; GB2596053A

Abstract

A method and a system for repairing a pothole is disclosed. The method may include: forming one or more undercut cavities in the pothole wall, below a surrounding road surface; clearing debris and removing loose asphalt pieces from a pothole; filling the pothole and the one or more undercut cavities with aggregates, and applying an expanding polymer base binder to fill at least part of the volume between the aggregates.

Description

SYNTHETIC BINDER FOR REPAIRING POTHOLES, APPARATUS AND METHOD OF MAKING THE SAME

FIELD OF THE INVENTION

The present invention generally relates to potholes and the repair thereof, and more particularly to NGAS (next-generation asphalt surface) material, its composition and related process application.

BACKGROUND OF THE INVENTION

Potholes are a common nuisance on roadways. They are structural failures in road surfaces, primarily caused by the presence of water in the underlying soil structure and the compounded effect of traffic passing over the affected area. Not only do they degrade the aesthetic appearance of an area, but they also pose a severe threat to the safety of road users.

In areas subject to freezing and thawing, frost heaving can damage a pavement and create cracks for water penetration. Moisture may seep through these cracks in the road surface towards the underlying soil. If temperatures drop sufficiently, the water may freeze. Upon freezing, it will expand in volume, resulting in ground movement or irreparable damage to the surface foundation, leaving under-surface voids. These processes result in road degradation. Eventually, the fatigue cracks grow to the point that the road surface disintegrates by the continuous wheel loads exerted by moving traffic, and a pothole is created.

In some areas, road deterioration is so extensive that repair costs become prohibitive. Regardless of the road design and quality of construction, eventually, all asphalt surfaces will crack due to both cold or hot weather. Potholes cause billions of dollars in vehicular damage and may lead to traffic-related deaths.

Preventive maintenance of potholes may be carried out but is not always effective due to the nature of the Asphalt materials in use. An initial preventative method may consist of surveying road surfaces for risk factors and early signs of failure. Further, the provision of adequate drainage (e.g. storm sewers) is essential for the removal of water build-up. Good construction practices should be used, such as well-drained base and sub-base soils. Additionally, ongoing maintenance of the structural integrity of the road ensures a reduction in water penetration. Present-day pothole repair methods are based on obsolete, centuries-old technologies. These methods are slow and ineffective, thus resulting in a large repair backlog. For example, it is a commonplace in the art to use spray injection patching using hot Asphalt emulsion pre-mixed with aggregates filling the pothole depression under high pressure. The void is first blasted with compressed air to clean the surface and remove any debris, then the surface of the void is sprayed and coated with asphalt emulsion. Secondly, the asphalt mix is sprayed into the void at a speed of up to 100 kph, compacting from the bottom up. The wet upper surface of the repaired area is then protected from traffic flow using sand.

There are several drawbacks of existing repair technologies, primarily that the repair may either be temporary or semi-permanent, with an average survival rate of nine months. Furthermore, these repair technologies require intensive manual labour and heavy equipment and thus can be exceedingly costly. Additionally, the repairs can often only be carried out in dry weather conditions.

New pothole repair methods are needed to maximise the useful life of road repair, utilised in any weather, rapidly, thus reducing lane closure time cuts (user delay costs) and enhances worker safety while improving the overall economic impact of road maintenance.

It is, therefore, an object of the invention to provide a novel pothole repair technology designed for roads, bridges and runaways, based on a synthetic material that possesses asphalt-concrete properties. It is a further object of the invention to propose an application method and apparatus thereof to mechanise and implement said repair technology.

SUMMARY OF THE INVENTION

Some aspects of the invention may be related to the method of repairing a pothole. In some embodiments, the method may include: forming one or more undercut cavities in the pothole wall, below a surrounding road surface; clearing debris and removing loose asphalt pieces from a pothole; filling the pothole and the one or more undercut cavities with aggregates; and applying an expanding polymer base binder to fill at least part of the volume between the aggregates.

In some embodiments, the method may further include levelling the filled aggregates. In some embodiments applying the expanding polymer base binder is by at least one of gravity casting and applying the binder from the bottom of the pothole upwards. In some embodiments, applying the expanding polymer base binder is to fill a first portion of the volume between the aggregates and wherein the method further comprises applying another polymer binder to fill a second portion of the volume between the aggregates, wherein the first polymer base has different chemical composition than the second polymer base binder. In some embodiments, filling the pothole and the one or more undercut cavities with aggregates comprises filling a first type of aggregates followed by filling a second type of aggregates, different than the first type. In some embodiments, the method may further include excavating the one or more undercut cavities based on the size of the aggregates’ particles. In some embodiments, filling the pothole is from an apparatus comprising containers containing at least one of: the aggregates, a first component for producing the expanding polymer base binder and the second component for producing the expanding polymer base binder.

In some embodiments, the method may further include covering the pothole with a rigid plate to control the expanding pressure that builds up inside the pothole. In some embodiments, the method may further include adding a known amount of fluid to the aggregates before applying the expanding polymer-based binder. In some embodiments, forming the one or more undercut cavities is by a cutting tool designed to form horizontal cuts.

Some additional aspects of the invention may be related to a method of making expanding polymer-based binder, in situ. In some embodiments the method may include: providing, from a first container, a first polymeric component; providing, from a second container, a second polymeric component, wherein the second polymeric component is configured to chemically react with the first polymeric component to form an expanding polymeric matrix; providing, reaction rate modifier from one of a third container and from the first container mixed with the first polymeric component; and mixing, in a mixer the first and the second polymeric components and the reaction rate modifier to form the expanding polymer-based binder. In some embodiments, fourth container storage may include the aggregates. In some embodiments, at least some of the containers and the mixer, are carried by a single apparatus and the mixing is performed in situ, prior to the application of the expanding polymeric based binder.

In some embodiments, the method may further include adding at least one of: one or more chemical additives and one or more fillers, from one of: a third container and from the first container mixed with the first polymeric component. In some embodiments, the first polymeric component is added in a range of 35-65 wt.%, the second polymeric component is added in a range of 35-65 wt.%. and the reaction rate modifier is added in a range of 0.1-15 wt.%. In some embodiments, one or more chemical additives are selected from: flame retardants; pigments; titanium dioxide; dyes; nano clays; pigments and friction modifiers. In some embodiments, the one or more fillers are selected from: elastomers; silica micro-particles; expanded graphite; carbon black; ash fly; nanotubes; graphene; basalt fibres; calcium carbonate; flexible and rigid fibres. In some embodiments, the first polymeric component is a polyol and the second component polymer is an isocyanate. In some embodiments, the first component is an epoxy and the second component is an amine. In some embodiments, the first polymeric component and the second polymeric component are selected to have a mixed viscosity of less than 10000 cP. In some embodiments, one or more chemical additives are selected to ensure that the mixed viscosity is less than 10000 cP. In some embodiments, one or more chemical additives are selected to ensure that the polymer-based binder is cured or partially cured to a solid in 20 minutes or less.

In some embodiments, the first polymeric component and the second polymeric component are selected to such that exothermic reaction occurs during polymerisation.

Some additional aspects of the invention may be related to a portable apparatus for carrying out the pothole repair on roads and making an expanding polymer-based binder in-situ. In some embodiments, the apparatus may include a portable platform holding: a first container for holding at least a first polymeric component; a second container for holding a second polymeric component; and a mixer for mixing the first and second polymeric components and a reaction rate modifier to form the polymer-based binder. In some embodiments, the reaction rate modifier is received from one of a third container held by the portable apparatus and mixed with the first polymeric component in the first container. In some embodiments, the second polymeric component is configured to chemically react with the first polymeric component to form an expanding polymeric binder.

Some additional aspects of the invention may be related to a synthetic composite material for repairing potholes. In some embodiments, the synthetic- composite material may include 30- 95 wt.% aggregates; and expanding polymer-based binder. In some embodiments, the aggregates and binder are selected that the aggregate surface is inert to the binder. In some embodiments, the polymer-based binder may include a base polymer and additives. In some embodiments, the polymer-based binder may include at least 50wt.% base polymer. In some embodiments, the aggregates are crushed stones; limestone; dolomite; basalt; granite; and recycled aggregates.

In some embodiments, the recycled aggregates comprise at least one of inorganic material, mineral material previously used in construction and other forms of industrial waste. In some embodiments, the aggregates are dolomite particle, and the expanding polymer-based binder comprises isocyanate. In some embodiments, the aggregates have a particle size of 5-25 mm. In some embodiments, the aggregates may further include an additional of fluids, for example, 1-3 wt.% water. In some embodiments, the polymer-based binder may include at least one of: 1-30 wt.% fibbers, 1 to 20 wt. % micro-silica, 0.5 to 10 wt.% expanded graphite, 0.5 to 30 wt.% carbon black, 0.5 to 30 wt.% calcium carbonate, 0.5 to 30 wt.% fly ash. In some embodiments, the synthetic binder may have at least one of the hardness of 80 to 120% compared to bitumen; a rigidity of 50% to 150% compared to Asphalt; a complex shear modulus of 80 to 120% compared to Asphalt; a scratch resistance expressed as the ratio of complex shear modulus to loss angle as Asphalt; a creep resistance as Asphalt, fatigue resistance expressed as the product of shear modulus; a loss angle as Asphalt; surface traction as Asphalt; and abrasion resistance as Asphalt.

Advantages of the present invention are set forth in detail in the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention and to illustrate its implementation, references are made, by way of examples and accompanying drawings in which numerals designate corresponding elements or sections.

In the accompanying drawings:

Figure 1 is a schematic diagram illustrating an exemplary trailer apparatus according to embodiments of the present invention.

Figures 2A, 2B and 2C, are schematic diagrams illustrating a portable apparatus for making an expanding polymer-based binder according to embodiments of the present invention.

Figures 3A and 3B are schematic diagrams illustrating an exemplary preparation of a pothole, prior to filling, according to embodiments of the present invention.

Figures 4A, 4B and 4C, are schematic diagrams illustrating an exemplary application of aggregates and foamable/ unfoamable polymers to a pothole according to embodiments of the present invention.

Figure 5 is a schematic diagram illustrating an exemplary anchoring system for the composite material according to embodiments of the present invention. Figure 6 is a flowchart of a method of repairing a pothole according to embodiments of the present invention.

Figure 7 is a flowchart of a method of making expanding polymer-based binder, in situ according to embodiments of the present invention.

It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.

DETAILED DESCRIPTION OF THE INVENTION

With specific reference now to the drawings in detail, it is emphasised that the particulars shown are for the purpose of example and solely for discussing the embodiments of the present invention and are presented to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention. The description taken with the drawings makes apparent to those skilled in the art, how several forms of the invention may be embodied in practice.

Before explaining the embodiments of the invention in detail, it is to be understood that the invention is not limited by the details of construction and the arrangement of the components in the descriptions or illustrated in the drawings. The invention is applicable to other embodiments and may be practised or carried out in various ways. Also, it is to be understood that the terminology employed herein is for the purpose of description and should not be regarded as limiting.

Some aspects and advantages of the invention may be related to a portable apparatus, methods and materials that may allow to fill and repair a pothole in a road, in several minutes, (e.g., less than 15 minutes), therefore reducing lane closure time cuts (user delay costs) and enhances worker safety while improving the overall economic impact of road maintenance. Such methods and material may allow the repaired pothole to function (e.g., stay filled) and lasts the entire life of the road life span (e.g., until the next road resurfacing), the pothole repair process may be carried out in any weather condition. The following term definitions are provided to aid in the interpretation of the invention:

The term “expanding ” generally refers to a material or a mixture of materials that are configured to expand it’s volume during one of hardening or mixing, for example when two polymeric components chemically react to form a polymer (polymerisation) the mixture is considered “expanding ” if the volume of the final polymer (hardened or semi-hardened) is larger than the volume occupied by the polymeric components. An expanding polymer may include additives that may cause the expansion, for example, foaming promoters.

The term “polymeric component” refers to any compound or mixture of compounds (e.g., a solution containing monomers) that upon mixing with an additional component will cause the polymerisation of the polymer. Nonlimiting examples of polymeric components may include: polyol to be mixed with isocyanate and epoxy to be mixed with an amine.

The term “synthetic” generally refers to an artificial composition that is produced by chemical synthesis. In the present context, ‘synthetic’ refers to materials that are engineered to possess similar attributes to asphalt-concrete.

The term “aggregate” generally refers to a material extracted from a quarry and crushed into various sizes. Aggregates may be natural or recycled. In the present context, aggregates are combined with the binder, the following foamable and unfoamable polymers, additives, fillers, colloids and a reaction rate modifier to create a synthetic composite material.

The term “monomer” generally refers to a molecule that can form a polymer.

The term “polymer” generally refers to a substance that has a molecular structure built up primarily or entirely from many units (monomers). In the present context, foamable and unfoamable polymers are combined with additional components to yield a low viscosity binder that can be applied to aggregates, following arrangement of the aggregates in the said pothole to form a composite material.

The term “reaction rate modifier” generally refers to a substance that increases (accelerator) or decreases (inhibitor) the rate of a chemical reaction. In the present context, reaction rate modifiers are utilised when combining the components to form a composite material to adjust and control the rate of the material consolidation, and compensating for ambient temperatures. The term “pot life” generally refers to the amount of time it takes for the initial viscosity of a mixed system to expand its liquid state two-fold and above, during which the polymer remains sufficiently liquid to be processed. In the present context, it refers to the rise-time for the predetermined mixed system in viscosity and is dependent upon temperature, catalyst (accelerator) presence or inhibitor presence.

According to some embodiments of the invention, a novel composition for repairing potholes is disclosed. The composition is a synthetic binder formulated to meet mechanical, thermal, rheological and physical properties similar to asphalt-concrete.

According to some embodiments of the invention, the synthetic binder may comprise foamable and unfoamable polymers containing additives of various hardness levels, silica micro particles, silica nanoparticles, nanoclays, expanded graphite, carbon black, fly ash, calcium carbonate, basalt fibres, flexible and rigid fibres that yield a binder which is applied on aggregates (natural or recycled) of various sizes, material, and classified by their Aggregate Impact Value (AIV) and Aggregate Crushing Value (ACV) for optimal pothole repair. The AIV is a measure of resistance to a sudden impact or shock, which may differ from the measure of resistance to a gradually applied compressive load, for example, AIV will be between 17 and 21%.

Aggregate Crushing Value (ACV) is a numerical index of the strength of aggregate and is commonly used in the construction of roads and pavements. The ACV indicates its strength; a lower crushing value is recommended for roads and pavements and provides a longer service life and a more economical performance. For example, ACV will be between 23 and 30%.

According to some embodiments of the invention, the ratio of the components within the polymer and the incorporated additives may be chosen to provide properties that are like asphalt-concrete such as mechanical, physical (hardness, resilience, strength), thermal (traction, temperature dependence) and rheological (modulus of elasticity, viscoelasticity, abrasion).

According to some embodiments of the invention, the properties of the synthetic binder formulation may be similar or superior to those of asphalt-concrete. According to some embodiments of the invention, the synthetic binder formulation may be applied to a pothole in a liquid state.

According to some embodiments of the invention, the synthetic binder formulation may not require any external heating source to increase the rate of polymerisation due to the exothermic reaction of the system.

According to some embodiments of the invention, the aggregates may be pre-treated concerning withstanding humidity, thus allowing the aggregates to be indifferent to the amount of moisture (in the form of wetness/snow/ice) already present in the pothole.

According to some embodiments of the invention, the aggregates may be pre-treated, to promote bonding between the aggregates and binder.

According to some embodiments of the invention, the composite material formulation may strengthen the structure of the road surrounding within the pothole during the repair.

According to some embodiments of the invention, the synthetic binder formulation may be highly resistant to UV radiation.

According to some embodiments of the invention, the synthetic binder formulation may be highly resistant to impact mechanical and shear forces, tear-resistance and tensile properties.

According to some embodiments of the invention, the synthetic binder formulation may be highly resistant to chemicals, humidity water, oil and grease.

According to some embodiments of the invention, the synthetic binder formulation may be highly resistant to fire and other forms and exposure to heat.

Figure 1 is a schematic diagram illustrating an exemplary trailer apparatus 100 according to embodiments of the present invention. The trailer 110 may be capable of being attached to a secondary vehicle via connector 120.

In some embodiments, connector 120 may be a clamp and latch mechanism.

Figures 2A, 2B and 2C, are schematic diagrams illustrating scanning methods of a pothole according to embodiments of the present invention. Figure 2A depicts a scene 200 wherein apparatus 210 (e.g., a vehicle) is in close proximity to a pothole 220 on road surface 230. In some embodiments, apparatus 210 may be configured to be placed, in real-time, in situ. For example, apparatus 210 may be a payload, mounted on a vehicle (as illustrated), and carried by any type of vehicle, trailer, airborne and the like.

In some embodiments, portable apparatus 210 for making an expanding polymer-based binder, in situ (e.g., next to pothole 220 on road surface 230) may include a first container 211 for holding at least a first polymeric component, a second container 212 for holding a second polymeric component and a mixer 215. For example, first container 211 may hold polyol or epoxy. In some embodiments, first container 211 may further hold at least one additive or filler to be mixed with the first polymeric components. In some embodiments, fourth container 214 may further hold aggregates. For example, first container 211 may further hold a reaction rate modifier. Other examples may include: one or more additives such as flame retardants; pigments; titanium dioxide; dyes; nano clays; pigments and friction modifiers and the one or more fillers are selected from: elastomers; silica micro-particles; expanded graphite; carbon black; ash fly; nanotubes; graphene; basalt fibres; calcium carbonate; flexible and rigid fibbers and any combination thereof.

In some embodiments, second container 212 may hold the second polymeric component, for example, isocyanate or an amine. In some embodiments, additional materials (e.g., fillers) may also be added to the second container.

In some embodiments, apparatus 210 may further include a third container that may include any one of the additives and/or fillers disclosed hereinabove; for example, the reaction rate modifier.

In some embodiments, mixer 215 may be any mixer known in the art that is configured to be held by portable apparatus 210. Mixer 215 may be configured to mix the first and second polymeric components and a reaction rate modifier to form the expanding polymer-based binder. In some embodiments, mixer 215 may further mix any additives or fillers to be included in the expanding polymer-based binder.

In some embodiments, a precise three-dimensional scan of the pothole may be carried out by a dedicated optical sensing system 240, as shown in Fig 2B. This may be instructed by a user 250 or via Augmented Reality (AR) hardware or tablet/ PC or smartphone, or maybe an automatic process, beginning upon arrival at the designated pothole. The 3D scan may be configured to map the pothole, regardless of obstructions such as water, ice, snow, mud, debris etc. The 3D scan may be ultrasonic, thermal, laser, visual, GPR, LiDAR or their combinations to provide an in-depth digital model of the pothole.

Figure 2C depicts further data that may be collected via optical sensing system 240 from the pothole 220, such as the composition of pothole layers 260, pothole volume and depth 270, temperature and relative humidity in the pothole and around the pothole 280 etc.

Figures 3A and 3B are schematic diagrams illustrating an exemplary preparation of a pothole, according to embodiments of the present invention. Prior to filling a pothole with the synthetic binder formulation, it may need to be thoroughly cleaned to provide an optimum surface for repair, and an undercut may be excavated out to aid the repair.

Figure 3A depicts a cleaning system 300 comprising air pressure ducts 310 and brushes 320, configured to clean pothole 330 prior to repair. The system may be able to remove loose dirt, dust particulates, small aggregates and debris to provide an optimum surface for which to apply the synthetic binder formulation (the binder).

Figure 3B depicts a mechanised undercutting system 350, consisting of a tool 360, configured to excavate out at least one undercut cavity 370 inside to the pothole 330. This channel may act as an undercut cavity filled with the aggregates and synthetic binder formulation, strengthening the surrounding road surface of the pothole via the provision of mechanical anchoring and powerful adhesion, described further below. The system 350 is configured to move laterally along the road surface so that it may excavate out further undercut cavity 380 (dotted).

In some embodiments, the cleaning system 310 and the excavating system 360 are combined into an individual system.

In some embodiments, the cleaning and excavating processes may be automated or may be carried out manually by a human.

Figures 4A, 4B and 4C are schematic diagrams illustrating an exemplary application of aggregates and foamable and/or unfoamable polymers, in a predetermined sequence, according to embodiments of the present invention. Figure 4A depicts filling the pothole 410 to be repaired with a plurality of aggregates 420 having an appropriate material, size distribution, classified AIV (Aggregate Impact Value) and ACV (Aggregate Crushing Value). These aggregates may be compacted and levelled by any suitable apparatus or manually. This may be followed by blending the elastomer and other additives in appropriate ratios with the expanding and/or non-expanding polymers.

Figure 4B depicts the injection of a predetermined controlled amount of blended material (binder) comprising expanding polymer binder 430 (as disclosed hereinbelow with respect to Figure 7) to the aggregates 420 in the pothole 410, followed by setting the blended expanding or non-expanding polymer to a predetermined ratio.

Figure 4C depicts covering the pothole 410 with a rigid plate 440 to control the pressure that builds up inside the pothole and to achieve precise levelling of the repair with respect to the road surface. The polymerisation process causes the voids between the aggregates, as well as the undercut cavities, made earlier, to be thoroughly penetrated and filled with the synthetic blended material formulation (the binder), producing a firm adhesion between the filled aggregates themselves and between the aggregates and the pothole surroundings.

The structure of the repaired pothole may include one, two or multiple layers possessing different aggregate size, material and/or different compositions of expanding and non expanding polymers.

The composite material used to patch the pothole may be comprised of the following: solid dry or wet aggregates, polymers, additives, fillers, pigments and a reaction rate modifier (accelerators and inhibitors).

In the case of multiple layers, the first layer may be followed by at least second layer, having the same or different expanding or non-expanding polymer and same or different aggregate size or type and placing an upper bound, rigid cover comprising flexible non-adhering layer having embossing layout to control the binder expansion level and surface flatness of the composite material with the road. The cover non-adhering layer (facing the road) allows the aggregates in the upper surface to remain exposed to the correct degree and not being covered by the binder, to create immediate contact with road vehicle tires to achieve required traction levels.

According to an embodiment of the invention, a first layer will comprise only expandable polymers and a second layer (placed atop the first layer) may comprise only non-expanding polymers. According to a further embodiment of the invention, the first expandable layer will comprise 50-90% of the pothole volume.

According to an embodiment of the invention, a first layer may comprise of non-expanding polymers.

In some embodiments, traction, roughness, and levelling of the repair may be determined by using rigid cover comprising a flexible non-adhering layer with low surface tension having an embossing layout and weight, placed atop the repaired pothole.

In some embodiments, the binder is applied to the pothole with the use of a pump.

In some embodiments, the binder is applied to the pothole manually.

In some embodiments, the polymers may be either Thermosetting or Thermoplastic.

In some embodiments, anti-slip material may be mixed into the binder surface or distributed on top of the binder surface.

Figure 5 is a schematic diagram illustrating an exemplary anchoring system for the composite material according to the embodiments of the present invention.

According to some embodiments of the invention, the anchoring system may be mechanical in nature. A mechanical lock may be created by undercutting 510, 512, 520, 522 the pothole 530, thus preventing the composite material from being torn off without disintegrating itself and/or the surrounding pavement. The composite material may also provide internal strength by penetrating cracks and the undercut itself, effectively shoring the pothole surface and its structure.

Reference is now made to Figure 6, which is a flowchart of a method of repairing a pothole according to some embodiments of the invention. The method of Figure 6 may be performed using any one of the apparatuses disclosed hereinabove; for example, apparatus 210. In step 610, one or more undercut cavities may be formed in the pothole wall, below a surrounding road surface. For example, undercut cavities 370 and 380 in pothole 330. In some embodiments, the undercuts may be formed by a cutting tool (e.g., tool 360) designed to form horizontal cuts. In some embodiments, the one or more undercut cavities may be excavated based on the size of the aggregates’ particles. In step 620, debris may be cleared, and loose asphalt pieces may be removed from a pothole, for example, as illustrated and discussed with respect to Fig. 3A.

In step 630, the pothole and the one or more undercut cavities may be filled with aggregates, for example, as illustrated in Fig. 4A. In some embodiments, the method may further include levelling the filled aggregates. In some embodiments, the pothole (e.g., pothole 410) may be filled first with the first type of aggregates followed by an additional second type of aggregates, different from the first type. For example, a first portion of the pothole may be filled with crushed stones and a second portion of the pothole may be filled with basalt.

In step 640, an expanding polymer base binder may be applied to fill at least part of the volume between the aggregates. In some embodiments, the expanding polymer base binder may be any one of the expanding binders disclosed herein, for example, the expanding binder disclosed with respect to the flowchart of Fig. 7. In some embodiments, applying the expanding polymer base binder maybe by at least one of gravity casting, and applying the binder from a bottom of the pothole upwards and the like. In some embodiments, the expanding polymer base binder may be applied to fill only a first portion of the volume between the aggregates and the method may further include applying another polymer binder to fill a second portion of the volume between the aggregates, wherein the other polymer base may have different chemical composition than the expanding polymer base binder. In some embodiments, the other polymer base binder may also be an expanding polymer. In some embodiments, the other polymer base binder may not be expanded.

In some embodiments, filling the pothole is from an apparatus comprising containers containing at least one of the aggregates, a first component for producing the expanding polymer base binder and the second component for producing the expanding polymer base binder, for example, portable apparatus 210.

In some embodiments, the method may further include covering the pothole with a rigid plate to control the expanding pressure that builds up inside the pothole. In some embodiments, the method may include adding a known amount of fluids (e.g., water, or water-based fluids, oil- based fluids and the like) to the aggregates before applying the expanding polymer-based binder. In some embodiments, the additional fluids may improve adhesion of aggregates to the binder and the pothole, and equalise the wetness of the aggregates (figure 2B, 214) with the wetness of the pothole during raining snowing and the like (figure 2C). Reference is now made to Fig. 7 which is a flowchart of a method of making expanding polymer-based binder, in situ, according to some embodiments of the invention. The method of Fig. 7 may be conducted using a portable device, such as portable device 210. The expanding polymer-based binder made using the method of Fig. 7 may be used in filling a pothole according to the method of Fig. 6. In step 710, a first polymeric component may be provided from a first container. For example, a polyol or an epoxy may be provided from first container 211.

In step 720, a second polymeric component may be provided from a second container. In some embodiments, the second polymeric component may be configured to chemically react with the first polymeric component to form an expanding polymeric binder. For example, isocyanate configured to react with polyol or amine configured to react with epoxy may be provided from second container 212. In step 730, a reaction rate modifier may be added from one of a third container and from the first container mixed with the first polymeric component. In some embodiments, the reaction rate modifier may be added from container 213 or may be pre-mixed with the first component.

In some embodiments, the first polymeric component may be added in a range of 35-65 wt.%. In some embodiments, the second polymeric component may be added in a range of 35-65 wt.%. In some embodiments, the reaction rate modifier may be added in a range of 0.1-15 wt.%. In some embodiments, the first polymeric component and the second polymeric component are selected to have a mixed viscosity of less than 10000 Cp. In some embodiments, one or more chemical additives are selected to ensure that the mixed viscosity is less than 10000 Cp. In some embodiments, the chemical additive may be a foaming agent configured to cause the expansion of the polymer-based binder by forming a foam structure. In some embodiments, the polymer- based binder may include at least one of the filler: 1-30 wt.% fibbers, 1 to 20 wt. % micro- silica, 0.5 to 10 wt.% expanded graphite, 0.5 to 30 wt.% carbon black, 0.5 to 30 wt.% calcium carbonate, 0.5 to 30 wt.% fly ash.

In some embodiments, the one or more chemical additives are selected to ensure that the polymer-based binder is cured or partially cured to a solid in 15 minutes or less, as to ensure quick repairing of the road and reducing lane closure time cuts (user delay costs).

In some embodiments, the first polymeric component and the second polymeric component are selected to such that exothermic reaction occurs during polymerisation. In step 740, the first and the second polymeric components and the reaction rate modifier may be mixed in a mixer to form the expanding polymer-based binder. For example, polyol and isocyanate may be mixed with the reaction rate modifier in mixer 215.

In some embodiments, the method may further include adding one or more chemical additives and/or fillers to the mixer, either as a pre-mixed with the first polymeric component or from third (or fourth) container 213. In some embodiments, the one or more chemical additives are selected from: flame retardants; pigments; titanium dioxide; dyes; nano clays; pigments and friction modifiers. In some embodiments, one or more fillers are selected from elastomers; silica micro-particles; expanded graphite; carbon black; ash fly; nanotubes; graphene; basalt fibres; calcium carbonate; flexible and rigid fibres.

In some embodiments, at least some of the containers and the mixer may be carried by a single apparatus, and the mixing is performed in situ, prior to the application of the expanding polymeric based binder, for example, by apparatus 210.

According to some embodiments of the invention, the anchoring system may be chemical in nature. A chemical bond may be formulated when liquid polymer wets the surface and maximises the chemical anchoring potential with the pavement and/or road surroundings. Polyurethane is known to stick well to polar materials such as Asphalt (which is present in existing road surfaces).

According to some embodiments of the invention, the Polyurethane used to form a chemical bond (the binder) may be made from Biopolymers, to provide a better environmentally- friendly green solution.

According to some embodiments of the invention, a dual anchoring system may be used, comprising both chemical and mechanical aspects.

In some embodiments, the expansion of the synthetic binder formulation results in an internal hydrostatic pressure which may be maintained through precise control of temperatures of the components of the synthetic binder formulation (containers 211, 212, 213). In different environments, humidity, wetness and temperature may affect the expansion of the foaming, so this may be monitored and compensated with additives and either an accelerator (catalyst) or an inhibitor to ensure correct levelling of the repaired pothole. According to some embodiments of the invention, the apparatus may be a rig that is configured to be towed (trailer) by a vehicle.

According to some embodiments of the invention, the apparatus may be an independent designated vehicle configuration or mounted as payload on a vehicle capable of moving under its power.

According to some embodiments of the invention, the trailer apparatus may further comprise an Internet of Things “IoT” suite that is configured to interface to at least one of the: Algorithm; cloud; IT hardware, and command and a control (C2) device for the system operator using a tablet, smartphone, PC or Augmented Reality (AR) hardware.

Some aspects of the invention may be related to a synthetic composite material for repairing potholes according to some embodiments of the invention. In some embodiments, the synthetic binder may fill potholes, such as potholes 220, 330 and 410. In some embodiments, the composite material may include 30-95 wt.% aggregates (e.g., aggregates 420) and expanding polymer-based binder (e.g., binder 430). In some embodiments, the aggregates and binder may be selected such that the aggregate surface is inert to the binder. In a nonlimiting example, the aggregates may include dolomite particle and the expanding polymer-based binder may include isocyanate.

In some embodiments, the polymer-based binder may include a base polymer and additives, for example, as disclosed with respect to the method of Figure 7 hereinabove.

In some embodiments, the polymer-based binder may include at least 50wt.% base polymer. In some embodiments, the aggregates may include crushed stones; limestone; dolomite; basalt; granite; and recycled aggregates. In some embodiments, the recycled aggregates may include at least one of inorganic material, mineral material previously used in construction and other forms of industrial waste. In some embodiments, the aggregates have a particle size of 5-25 mm.

In some embodiments, the aggregates may include an additional amount of fluids, for example, 1-3 wt.% water.

In some embodiments, the synthetic composite material may have at least one of: hardness of 80 to 120% compared to bitumen, a rigidity of 50% to 150% compared to Asphalt, complex shear modulus of 80 to 120% compared to Asphalt, scratch resistance expressed as the ratio of complex shear modulus to loss angle as Asphalt, creep resistance as Asphalt, fatigue resistance expressed as the product of shear modulus, fatigue resistance expressed as the product of shear modulus and a loss angle as Asphalt, surface traction as asphalt and abrasion resistance as Asphalt.

In some embodiments, the bindermay include at least one of: 1-30 wt.% fibres, 1 to 20 wt. % micro-silica, 0.5 to 10 wt.% expanded graphite, 0.5 to 30 wt.% carbon black, 0.5 to 30 wt.% calcium carbonate, 0.5 to 30 wt.% fly ash.

According to some embodiments of the invention, a patch correction kit may be utilised for enabling manual corrections after repair once it is determined necessary by QA procedures in- situ or visual inspection by the foreman. The kit may utilise the same binder with a dispersion apparatus for dispersing the required dose where needed, and the repaired pothole surface may be controlled via the usage of a flexible non-adhering material layer (facing the road) attached to a rigid cover.

According to some embodiments of the invention, the colour of the repaired pothole surface may be controlled via binder pigmentation for aesthetic or commercial purposes. Using a combination of Magenta, Cyan, Yellow, White and Black colourants, almost any colour and halftone can be produced.

According to some embodiments of the invention, the traction of the repaired pothole surface may be controlled by adjusting at least one of aggregate tip exposure, aggregate material shape and size, aggregate aspect ratio, filler percolation and usage of friction modifiers and by placing an upper bound, rigid cover comprising a flexible non-adhering layer having embossing layout to control the expansion level and surface flatness of the expanded polymer binder with the road. The cover non-adhering layer may allow aggregates in the surface to remain exposed to the correct degree and not being covered by the binder to create immediate contact with road vehicle tires to achieve required traction levels.

According to some embodiments of the invention, the traction qualities of the repaired pothole surface may be controlled via the usage of a flexible non-adhering material layer attached to a rigid cover towards pothole creating embossed surface texture. According to some embodiments of the invention, the pothole repair method may be carried out in any weather condition.

According to some embodiments of the invention, the method may be carried out in a temperature range from -30 (minus) degrees Celsius to +90 (plus) degrees Celsius. According to some embodiments of the invention, the method may utilise recycled matter, additives, aggregates or recycled and industrial waste to reduce global wastage.

According to some embodiments of the invention, the method and materials may apply to entire road surfacing, road resurfacing, road micro-surfacing and road paving and controlled low strength material (CLSM) applications. According to some embodiments of the invention, the pothole repair may be applicable to road scraping and milling processes.

The aforementioned diagrams illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer hardware and algorithm program products according to various embodiments of the present invention. In this regard, each portion in the portion diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the portion may occur out of order noted in the figures. For example, two portions shown in succession may, in fact, be executed substantially concurrently, or the portions may sometimes be executed in the reverse order, depending upon the functionality involved, It will also be noted that each portion of the portion diagrams, and combinations of portions in the portion diagrams, can be implemented by particular purpose hardware-based systems that perform the specified functions or acts, or combinations of specialised purpose hardware and computer instructions.

As will be appreciated by one skilled in the art, aspects of the present invention may be embodied as a system or an apparatus. Accordingly, aspects of the present invention may take the form of an entirely hardware embodiment or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit”, “module” or “system.” The aforementioned figures illustrate the architecture, functionality, and operation of possible implementations of systems and apparatus according to various embodiments of the present invention. Where referred to in the above description, an embodiment is an example or implementation of the invention. The various appearances of “one embodiment”, “an embodiment” or “some embodiments” do not necessarily all refer to the same embodiments.

Although various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination. Conversely, although the invention may be described herein in the context of separate embodiments for clarity, the invention may also be implemented in a single embodiment.

Reference in the specification to “some embodiments”, “an embodiment”, “one embodiment” or “other embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments, of the inventions. It will further be recognised that the aspects of the invention described hereinabove may be combined or otherwise coexist in embodiments of the invention.

It is to be understood that the terminology employed herein is not to be construed as limiting and are for descriptive purpose only.

The principles and uses of the teachings of the present invention may be better understood with reference to the accompanying description, figures and examples.

It is to be understood that the details set forth herein do not construe a limitation to an application of the invention.

Furthermore, it is to be understood that the invention can be carried out or practised in various ways and that the invention can be implemented in embodiments other than the ones outlined in the description above, for instance, trucks, commercial vehicles, motorcycles, airborne and mobile independent or self-sustaining payload.

It is to be understood that the terms “including”, “comprising”, “consisting” and grammatical variants thereof do not preclude the addition of one or more components, features, steps, or integers or groups thereof and that the terms are to be construed as specifying components, features, steps or integers. If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional elements.

It is to be understood that where the claims or specification refer to “a” or “an” element, such reference is not be construed that there is only one of that element.

It is to be understood that where the specification states that a component, feature, structure, or characteristic “may”, “might”, “can” or “could” be included, that particular component feature, structure, or characteristic is not required to be included.

Where applicable, although state diagrams, may be used to describe embodiments, the invention is not limited to those diagrams or to the corresponding descriptions. For example, flow need not move through each illustrated state, or in precisely the same order as illustrated and described.

Methods of the present invention may be implemented by performing or completing manually, automatically, or a combination thereof, selected steps or tasks.

The term “method” may refer to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to or readily developed from known manners, means, techniques and procedures by practitioners of the art to which the invention belongs.

The descriptions, examples and materials presented in the claims and the specification are not to be construed as limiting but rather as illustrative only.

Meanings of technical and scientific terms used herein are to be commonly understood as by one of ordinary skill in the art to which the invention belongs unless otherwise defined.

The present invention may be implemented in the testing or practice with materials equivalent or similar to those described herein.

While the invention has been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention, but rather as exemplifications of some of the embodiments. Other or equivalent variations, modifications, and applications are also within the scope of the invention. Accordingly, the scope of the invention should not be limited by what has thus far been described, but by the appended claims and their legal equivalents.

Claims

1. A method of repairing a pothole, the method comprising: forming one or more undercut cavities in the pothole wall, below a surrounding road surface; clearing debris and removing loose asphalt pieces from said pothole; filling the pothole and the one or more undercut cavities with aggregates; and applying an expanding polymer base binder to fill at least part of the volume between the aggregates.

2. The method of claim 1, further comprising: levelling the filled pothole.

3. The method of claim 1 or claim 2, wherein applying the expanding polymer base binder is by at least one of gravity casting and applying the binder from a bottom of the pothole upwards.

4. The method according to any one of claims 1-3, wherein applying the expanding polymer base binder is to fill a first portion of the volume between the aggregates and wherein the method further comprises applying a further polymer binder to fill a second portion of the volume between the aggregates, wherein the first polymer base has a different chemical composition than the second polymer base binder.

5. The method according to any one of claims 1-4, wherein filling the pothole and the one or more undercut cavities with aggregates comprises, filling a first type of aggregates followed by filling a second type of aggregates, different than the first type.

6. The method according to any one of claims 1-5, further comprising: excavating the one or more undercut cavities based on the size of the aggregates’ particles.

7. The method according to one of claims 1-6, wherein filling the pothole is from an apparatus comprising containers containing at least one of the aggregates, a first component for producing the expanding polymer base binder and the second component for producing the expanding polymer base binder.

8. The method of claim 1-7 further comprising: covering the pothole with a rigid plate to control the expanding pressure that builds up inside the pothole and levelling.

9. The method according to any one of claims 1-7, further comprising adding a known amount of fluid to the aggregates prior to applying the expanding polymer-based binder.

10. The method according to any one of claims 1-9, wherein forming the one or more undercut cavities is by a cutting tool designed to form horizontal cuts.

11. A method of making expanding polymer-based binder, in situ, the method comprising: providing, from a first container, a first polymeric component; providing, from a second container, a second polymeric component, wherein the second polymeric component is configured to chemically react with the first polymeric component to form an expanding polymeric matrix; providing a reaction rate modifier from one of a third container and the first container mixed with the first polymeric component; mixing, in a mixer, the first and the second polymeric components and the reaction rate modifier to form the expanding polymer-based binder; wherein at least some of the containers and the mixer are carried by a single apparatus, and the mixing is performed in situ, prior to the application of the expanding polymeric based binder.

12. The method of claim 11, further comprising: adding at least one of one or more chemical additives and one or more fillers, from one of a third container and the first container mixed with the first polymeric component.

13. The method of claim 11, wherein the first polymeric component is added in a range of 35- 65 wt.%, the second polymeric component is added in a range of 35-65 wt.%. and the reaction rate modifier is added in a range of 0.1-15 wt.%.

14. The method according to any one of claims 12-13, wherein the one or more chemical additives are selected from: flame retardants; pigments; titanium dioxide; dyes; nano clays; pigments and friction modifiers and the one or more fillers are selected from: elastomers; silica micro-particles; expanded graphite; carbon black; ash fly; nanotubes; graphene; basalt fibres; calcium carbonate; flexible and rigid fibres.

15. The method according to any one of claim 11-14, wherein the first polymeric component is a polyol and the second component polymer is isocyanate or wherein the first component is an epoxy and the second component is an amine.

16. The method according to any one of claim 10-16, wherein the first polymeric component and the second polymeric component are selected to have a mixed viscosity of less than 10000 cP.

17. The method of claim 16 wherein the one or more chemical additives are selected to ensure at least one of that the mixed viscosity is less than 10000 cP and that the polymer-based binder is cured or partially cured to a solid in 15 minutes or less.

18. A portable apparatus for making an expanding polymer-based binder, in situ comprising: a portable platform holding: a first container for holding at least a first polymeric component; a second container for holding a second polymeric component; and a mixer for mixing the first and second polymeric components and a reaction rate modifier to form the polymer-based binder, wherein the reaction rate modifier is received from one of a third container held by the portable platform and mixed with the first polymeric component in the first container, and wherein the second polymeric component is configured to chemically react with the first polymeric component to form an expanding polymeric matrix

19. A synthetic composite material for repairing potholes, comprising: 30-95 wt.% aggregates; and an expanding polymer-based binder.

20. The synthetic composite material of claim 19, wherein the aggregates and polymer-based binder are selected such that the aggregate surface is inert to the binder.

21. The synthetic composite material of claim 19 or claim 20, wherein the polymer-based binder comprises at least 50 wt.% base polymer and additives.

22. The synthetic composite material of claim 19-21, wherein the aggregates are crushed stones; limestone; dolomite; basalt; granite; and recycled aggregates, and wherein the recycled aggregates comprise at least one of inorganic material, mineral material previously used in construction and other forms of industrial waste, and wherein the aggregates have a particle size of 5-25 mm.

23. The synthetic composite material according to any one of claims 19-22, wherein the aggregates comprises an additional amount of fluids.

24. The synthetic composite material according to any one of claims 19-23 having at least one of: the hardness of 80 to 120% compared to bitumen; a rigidity of 50% to 150% compared to Asphalt; complex shear modulus of 80 to 120% compared to Asphalt; scratch resistance expressed as the ratio of complex shear modulus to loss angle as Asphalt; creep resistance as Asphalt, fatigue resistance expressed as the product of shear modulus; a loss angle as Asphalt; surface traction as Asphalt; and abrasion resistance as Asphalt.

25. The synthetic composite material according to any one of claims 19-24, wherein the polymer-based binder comprises at least one of 1-30 wt.% fibres, 1 to 20 wt. % micro-silica, 0.5 to 10 wt.% expanded graphite, 0.5 to 30 wt.% carbon black, 0.5 to 30 wt.% calcium carbonate, 0.5 to 30 wt.% fly ash.