WO2022269274A1

WO2022269274A1 - Asphalt quality

Info

Publication number: WO2022269274A1
Application number: PCT/GB2022/051616
Authority: WO
Inventors: Gary Alan COOK
Original assignee: Asphalt-Iq Limited
Priority date: 2021-06-23
Filing date: 2022-06-23
Publication date: 2022-12-29
Also published as: EP4326944A1; AU2021204265A1

Abstract

A system 1 comprising a database 7 (storing respective information for each respective region of a plurality of regions of asphalt pavement) and a respective visible identifier 3, (in proximity to each respective region, by which the respective information is identifiable in the database).

Description

ASPHALT QUALITY

FIELD

The invention relates to methods and apparatus for managing asphalt pavement.

BACKGROUND

Asphalt pavement is widely used around the world for roads, car parks and pathways, etc. The quality of the pavement surface and the durability of the pavement depends on a wide range of parameters, such as details of the asphalt mix, the temperature of the mix when it is applied, the ambient temperature during the application and the extent to which the mix is compacted. Life cycle parameters, such as weather and traffic loading, also impact upon the condition and maintenance requirements of the pavement.

To efficiently manage asphalt pavement, these parameters need to be tracked. To hold suppliers (etc) to account, it is also useful to track the suppliers responsible for various regions of asphalt and/or parameters (e.g. to track the supplier who supplied a particular mix, or the contractor who compacted it). This information enables maintenance schedules to be maintained and optimised, and allows for suppliers to be held to account.

Compiling and maintaining such data is a huge task in the context of the many thousands of kilometres of pavement under the care of a typical road-managing authority. The task is compounded by ad hoc changes made by, for example, utility providers cutting into the asphalt to lay pipes and/or cables, etc then patching the pavement. Such patches are common failure points.

Some road-managing authorities employ "asphalt tags" akin to the tags described in US patent no. 4,888,896. Such tags have been allocated in colour-coded sets to different asphalt-laying authorities. By way of example, an electricity company might be given blue tags whilst a gas supplier is given red tags. When the gas company cuts a trench and then patches the asphalt, they embed their red tag in the surface of the asphalt so that the gas company is identifiable as the authority responsible for that particular patch.

This system enables some degree of accountability in that, if a patch deteriorates, the responsible party can be identified and asked to make suitable repairs. It also provides a store of information upon which maintenance schedules might be based. Road maintenance authorities can reach out to the gas company identified by their red tag for data characterising a particular patch to track down information. In practice, tracking down such information is laborious and the necessary records are often incomplete.

A literature search reveals Kelsey, Chris 2014, RFID Smart Geosynthetics Enable Talking Road, Geosynthetica, accessed 18 June 2021 , https://www.geosynthetica.com/rfid-smart-geosynthetics-roads/ describing RFID tag- equipped geosynthetic material, which is rolled out between a road bed and a new layer of asphalt during road repair. The present inventor has found that similar systems are impractical because the RFID tags cannot reliably be located, amongst other problems.

With the foregoing in mind, the present invention aims to provide improvements, or at least alternatives, for those concerned with managing asphalt pavement.

It is not admitted that any of the information in this patent specification is common general knowledge, or that the person skilled in the art could be reasonably expected to ascertain or understand it, regard it as relevant or combine it in any way before the priority date.

SUMMARY

One aspect of the invention provides an identifier for asphalt pavement comprising an upper body portion; and below the upper body portion an anchor arrangement; wherein the identifier is capable of withstanding more than 120°C and otherwise configured to be pressed into soft asphalt to embed the identifier, to create a visible identifier in the asphalt pavement.

Preferably, the identifier comprises an RFID tag. The identifier may comprise a shield for shielding the RFID tag. The shield may be adhered to the upper body. Optionally, the shield is a PTFE (e.g. Teflon™) shield. In some embodiments, the shield is a disk having a diameter of about 25.4 mm diameter. The RFID tag may be a disk having a diameter of about 25.4 mm diameter.

Asphalt is often not more than 40 mm deep. The identifier is preferably not more than 35 mm high, or more preferably not more than 30 mm high, e.g. not more than 25 mm high.

The upper body portion is preferably a horizontal body portion. The upper body portion is preferably more than 3 mm thick. In an embodiment, it is about 6 mm thick.

Another aspect of the invention provides a method of installing asphalt pavement comprising pressing the identifier into asphalt whilst the asphalt is soft. This may entail positioning the identifier to be flush with, or below, a top of the asphalt pavement when the asphalt pavement is finished. Preferably, it entails positioning the identifier to be below a top of the asphalt pavement when the asphalt pavement is finished. Optionally, the pressing comprises directly pressing the identifier with a gloved hand. The method may comprise compacting asphalt surrounding the identifier after the pressing.

Another aspect of the invention provides a system comprising a database storing respective information for each respective region of a plurality of regions of asphalt pavement; and a respective visible identifier, in proximity to (e.g. within or adjacent to) each respective region, by which the respective information is identifiable in the database. The respective visible identifier may be embedded in asphalt and/or comprise an RFID tag or NFC tag.

The system preferably comprises a hand-held reader for reading the visible identifiers. The reader may be a smart phone. Optionally the system is configured to provide a human operator in proximity to a respective region with at least some of the respective information.

In one implementation one of the regions is a patch.

The respective information preferably comprises one or more of asphalt mix, asphalt supplier, test data, weather information and traffic data. Another aspect of the invention provides a method comprising reading a visible identifier in proximity to a region, of asphalt pavement, with which respective information is associated; and transmitting a signal corresponding to the unique identifier to cause a remote database to reply with the respective information. Another aspect of the invention provides a method comprising receiving a signal corresponding to a visible identifier in proximity to a region, of asphalt pavement, with which respective information is associated; and replying with the respective information.

Another aspect of the invention provides a method comprising placing in proximity to a region of asphalt pavement a visible identifier by which information specific to the region is indexable.

Another aspect of the invention provides a region of asphalt pavement in combination with a visible identifier by which information specific to the region is indexable. BRIEF DESCRIPTION OF DRAWINGS

Figure 1a is a perspective view of an asphalt tag from above;

Figure 1b is a perspective view of an asphalt tag from below;

Figure 2 schematically illustrates a data management system in use; and Figure 3 is a flow chart illustrating the use of the system.

DESCRIPTION OF EMBODIMENTS

Disclosed is a system 1 comprising an identifier in the form of asphalt tag 3, a reader in the form of mobile phone 5 and a database 7 which, in this example, is stored within a server 7a.

The tag 3 is configured to be pressed into the surface of the asphalt as it is laid. For this purpose preferred tags are capable of withstanding more than 120°C, e.g.

180°C. It comprises an upper body portion 3a, which in this case takes the form of a disc in the vicinity of 40 mm in diameter by about 6 mm thick. An anchor arrangement 3b projects downwardly from the body portion 3a. The anchor arrangement may comprise legs, e.g. legs extending down from a periphery of the upper body portion.

In this case, it takes the form of three barbed legs equispaced about the perimeter of the disc. The tag 3 is about 19 mm high, i.e. the legs project about 13 mm down below the upper body portion. The legs are preferably configured to hook into the asphalt. In this example, each of the legs is so configured by the inclusion of a small upward-facing landing outward beyond the periphery of the upper body portion 3c. After the tag 3 is pressed into place and the surrounding asphalt compacted, these landings interlock with the surrounding asphalt to hold the tag in place.

Once the legs have been pressed into the soft asphalt and the asphalt is set, the tag 3 is securely retained at the surface of the asphalt whereat it is visible, i.e. visible to the naked eye. The tag 3 is preferably a unique identifier whereby one tag can be distinguished from all other tags, as opposed to (for example) merely identified as one of the many red tags allocated to the gas company.

This might be as simple as each tag bearing its own reference number, visible to a human reader, although other options more susceptible to machine reading are preferred. In one variant, a QR code may be embossed on the upper surface of the body 3a. More preferably, the tag 3 incorporates an RFID tag, such as an NFC tag. The RFID tag may comprise the material of the bulk of the tag 3. Alternatively, it may be a discrete tag, e.g. embedded within or adhered underneath the body 3a.

Preferably, the RFID tag is shielded from the asphalt below. In the case of an RFID tag embedded within the body 3a, the tag may be centrally positioned whereby a lower layer of material forms a shield integral with the upper body 3a.

For the avoidance of doubt, "integral" and similar terminology is used herein in its conventional sense to refer to a single, continuous body of material whereby, as the wording is used herein, bodies may be integrated by welding but not by conventional mechanical fastening.

In a preferred implementation, the RFID tag comprises a 1" coin NFC tag 3c - that is, a tag in the form of a disk having a diameter of about 25.4 mm. For the avoidance of doubt, 25 mm is about 25.4 mm as the terminology is used herein. Such tags are freely and economically available.

Most preferably, a shield 3d is attached to shield the NFC tag. In this example, the shield is another economically available off-the-shelf part in the form of a PTFE furniture slider. The sliders take the form of a disk comprising a slightly convex bottom and, on top, backing material removable to reveal an adhesive surface.

In the illustrated example of the system, the 1" coin NFC tag 3c is adhered to an underside of the upper body portion 3a before the shield 3c is adhered to the bottom of the 1" coin NFC tag 3c. The tag 3c is thereby sandwiched in place and protected from above and below. In particular, the underlying shield 3d shields the 1" coin NFC tag 3c from hot, sharp portions of the asphalt as the tag is pressed down into place.

Preferably, the system 1 comprises an app (i.e. a set of instructions) that configures the mobile phone 5 to read the tag 3 and co-operate with the database 7. Preferably, the co-operation is via a telecommunications system TS, although in principle the mobile phone (or other reader) might store identifying information, to retrieve information from the database 7 when brought in physical proximity thereto.

Preferably, the tags are laid as part of the asphalt installation process. Asphalt is a blend of crushed rock, sand and bitumen. Preferably, it is hot mixed at about 180°C. This hot mix is typically placed with an asphalt paving machine that screeds the material as it is laid down to provide initial compaction. The asphalt is usually at least 120°C as it is placed.

Preferably, the tag 3 is placed once the asphalt has been screeded (or otherwise smoothed) but prior to the final compaction operations. In this example, the tag is placed using a gloved hand and pressed into the soft asphalt below the finished level of the smooth, soft asphalt mix. The asphalt is then compacted, preferably to at least 95% of refusal. Preferably, the tag is pushed (by the gloved hand) deep enough that the tag 3 sits about 5 mm to 10 mm below a surface of the road. Depressing the tag in this way, or at least ensuring that the tag is not proud, reduces the risk of dislodgement, e.g. the risk of a tag being dislodged by a snow plough. The shield also serves to protect the NFC tag during freeze/thaw cycles and other movements within the asphalt layer.

The mobile phone 5 may be used at the installation stage, e.g. shortly after the asphalt has cooled. Preferably, the tag 3 is activated at step 101 and then embedded 103 in the asphalt prior to initial quality control data being uploaded 105. The initial data may comprise details of the asphalt mix, the asphalt supplier, test data and/or weather information. The uploading process entails the mobile phone 5 relaying this initialising information and identifying information (corresponding to the tag 3) to the server 7 whereat the data are stored in relation to each other. Subsequent test data may be uploaded 107. Subsequent test data may identify the party responsible for testing and comprise summary data characterising the quality of the asphalt and raw test data. Again, this data is preferably uploaded to the database 7 and stored in relation to the respective identifying tag.

Over time, historical data indexed with respect to the unique tag can be uploaded 109a, 109b. This may comprise, for example, traffic and/or weather data. The traffic data may comprise a count of vehicle 5, a count per unit of time and/or details related to the weight of the vehicles moving over the road surface.

Each of steps 105, 107, 109a, 109b may be associated with a respective tag scanning operation 111. Likewise, the tag can be scanned 111 to subsequently retrieve information.

In a preferred variant of the app, moving the mobile phone into proximity to the tag automatically scans 111 and opens 113 the app and causes the app to display 115 a dashboard in which key quality indices are displayed 117 and asset management data is displayed 119. The software may also display 121 historical climate and traffic data. These steps feed into quality and asset management decisions 123.

Advantageously a party interested in the data for a particular region of asphalt can locate the tag because it is visibly mounted in the road surface, and retrieve the respective data for that particular region of asphalt from the database 7. Preferably, this retrieval is via the mobile phone 5 and the database 7 is responsive thereto whereby operators on the ground can be provided with immediate, complete and accurate data.

The preferred method of managing asphalt pavement comprises all authorised asphalt-laying parties being required to utilise the tags 3 and those tags 3 being co- operable with a single central database 7. Utilising the tags 3 is simple and convenient for the end users and, by ensuring that each of the tags co-operates with the same central database, enables a single complete record of the data pertaining to each particular region of asphalt to be maintained. This overcomes the problems associated with data being fragmented across various separate asphalt-laying entities. While the above description refers to one embodiment of managing asphalt pavement, it will be appreciated that other embodiments can be adopted by way of different combinations of features. Such embodiments fall within the spirit and scope of this invention. By way of example, whereas an advantageous tag 3 has been described, variants of the methods described herein may be employed in connection with other forms of tag, e.g. a simple puck comprising an RFID tag pressed into the asphalt so as to remain visible would be advantageous over similar pucks simply mixed in with the asphalt. Vice versa, variants of the tag 3 may be employed in connection with other methods. The term "comprises" and its grammatical variants has a meaning that is determined by the context in which it appears. Accordingly, the term should not be interpreted exhaustively unless the context dictates so.

Claims

1. An identifier for asphalt pavement comprising an upper body portion; and below the upper body portion an anchor arrangement, an RFID tag, and a shield for shielding the RFID tag; wherein the identifier is capable of withstanding more than 120°C and otherwise configured to be pressed into soft asphalt to embed the identifier, to create a visible identifier in the asphalt pavement.

2. The identifier of claim 1 wherein the shield is adhered to the upper body.

3. The identifier of claim 1 wherein the shield is a PTFE shield.

4. The identifier of claim 1 , 2 or 3 wherein the shield is a disk having a diameter of about 25.4 mm diameter.

5. The identifier of any one of claims 1 to 4 wherein the RFID tag is a disk having a diameter of about 25.4 mm diameter.

6. The identifier of any one of claims 1 to 5 wherein the identifier is not more than 30 mm high.

7. The identifier of any one of claims 1 to 6 wherein the upper body portion a horizontal body portion.

8. A method of installing asphalt pavement comprising pressing the identifier of any one of claims 1 to 7 into asphalt whilst the asphalt is soft.

9. The method of claim 8 comprising positioning the identifier to be flush with, or below, a top of the asphalt pavement when the asphalt pavement is finished.

10. The method of claim 8 comprising positioning the identifier to be below a top of the asphalt pavement when the asphalt pavement is finished.

11. The method of claim 8, 9 or 10 wherein the pressing comprises directly pressing the identifier with a gloved hand.

12. The method of any one of claims 8 to 11 comprising compacting asphalt surrounding the identifier after the pressing.

13. A system for asphalt pavement; the asphalt pavement comprising asphalt, the system comprising a database storing respective information for each respective region of a plurality of regions of the asphalt pavement; and a respective visible identifier, visibly mounted in the asphalt pavement, in proximity to each respective region and by which the respective information is identifiable in the database; wherein the respective information comprises initial data and traffic data; the initial data comprises one or more of asphalt mix, asphalt supplier, test data and weather information; and each respective visible identifier is capable of withstanding more than 120°C; comprises a respective upper body portion and a respective anchor arrangement projecting downwardly from the respective upper body portion; and was pressed into the asphalt, whilst the asphalt was soft, as the asphalt was installed and such that the respective visible identifier is embedded in the asphalt.

14. The system of claim 13 wherein each respective visible identifier comprises a respective RFID tag.

15. The system of claim 14 wherein each respective RFID tag is a respective NFC tag.

16. The system of claim 14 or 15 wherein each respective RFID tag is embedded within or adhered underneath the respective upper body portion.

17. The system of any one of claims 13 to 16 comprising a hand-held reader for reading the visible identifiers.

18. The system of claim 17 wherein the reader is a smart phone.

19. The system of any one of claims 13 to 18 wherein the system is configured to provide a human operator in proximity to a respective region with at least some of the respective information.

20. The system of any one of claims 13 to 19 wherein one of the regions is a patch.

21. The system of any one of claims 1 to 20 wherein the respective information comprises post-installation weather data.

22. A method for asphalt pavement; the asphalt pavement comprising asphalt; the method comprising reading a visible identifier, visibly mounted in the asphalt pavement, in proximity to a region of the asphalt pavement and with which respective information is associated; and transmitting a signal corresponding to the visible identifier to cause a remote database to reply with at least some of the respective information; wherein the respective information comprises initial data and traffic data; the initial data comprises one or more of asphalt mix, asphalt supplier, test data and weather information; and the visible identifier is capable of withstanding 120°C; comprises a respective upper body portion and a respective anchor arrangement projecting downwardly from the respective upper body portion; and was pressed into the asphalt, whilst the asphalt was soft, as the asphalt was installed and such that the respective visible identifier is embedded in the asphalt.

23. The method of claim 22 wherein the reading is with a hand-held reader.

24. The method of claim 2 wherein the reading is with a smart phone.

25. A method for asphalt pavement; the asphalt pavement comprising asphalt; the method comprising a remote database receiving a signal corresponding to a visible identifier, visibly mounted in the asphalt pavement and in proximity to a region of the asphalt pavement and with which respective information is associated; and replying with at least some of the respective information; wherein the respective information comprises initial data and traffic data; and the initial data comprises one or more of asphalt mix, asphalt supplier, test data and weather information; and the visible identifier is capable of withstanding 120°C; comprises a respective upper body portion and a respective anchor arrangement projecting downwardly from the respective upper body portion; and was pressed into the asphalt, whilst the asphalt was soft, as the asphalt was installed and such that the respective visible identifier is embedded in the asphalt.

26. The method of any one of claims 22 to 25 where the identifier is embedded in asphalt.

27. The method of any one of claims 22 to 26 wherein the identifier comprises an RFID tag.

28. The method of any one of claims 22 to 26 wherein the identifier comprises an

NFC tag.

29. The method of any one of claims 22 to 28 the region is a patch.

30. The method of any one of claims 22 to 29 wherein the respective information comprises post-installation weather data.