GB2540044A

GB2540044A - Pot hole repair system

Info

Publication number: GB2540044A
Application number: GB1610566.0A
Authority: GB
Inventors: Albert Chamberlain Denis
Original assignee: Epicuro Ltd
Current assignee: Epicuro Ltd
Priority date: 2014-07-01
Filing date: 2014-07-01
Publication date: 2017-01-04
Anticipated expiration: 2034-07-01
Also published as: GB2540044B; GB201411683D0; GB201610566D0; GB2511709A; GB2511709B

Abstract

A repair system for repairing a defect 304 such a pot hole in a road surface, or pavement, is disclosed. The defect defines a surface for repair and a recess to receive repair material during a repair process. A thermocouple 302 sensor is located in or adjacent to the defect surface and monitors the temperature at a boundary between the defect surface and the repair material before and optionally during repair of the road surface. A controller 303 receives data from the thermocouple sensor and is operable to monitor temperature data. More than one thermocouple may be used to determine how temperature varies across the defect and the controller operates an array of heating elements 400 to create an optimized heating pattern for improved repair. An infrared radiant point detector or camera may be used in addition to obtain temperature data. Pressure data may also be obtained from a sensor placed in a hole drilled in the road surface.

Description

POT HOLE REPAIR SYSTEM

This invention relates to a survey system and a repair system for repairing defects, for example pot holes, in a road surface.

Background to the invention

There are currently a number of pot-hole and patch repair machines available for repdring defects in road surfaces, such as for example asphalt road surfaces. However, the conventional repair machines are typically large, of considerable weight and require mechanical manipulation, such as for example requiring the use of a JCB machine. In addition, a low loader transporter is usually required to transport the JCB machine to the desired location. Conventional repair machines are of limited use in restricted locations, such as for example in a narrow road, and often require complete closure of the road.

Furthermore, conventional repair machines only take into account the dimensions of the defect to provide the appropriate path repair. The repair machines do not take into account the condition of the ground material beneath the road svnface. The resultant patch repair often has a limited life time and fails due to the poor condition of the underlying ground material adjacent die repaired defect.

The repair machines are usually restricted with regards to the size and/or shape of the patch repair that can be provided by the machine. This may therefore result in the machine providing a patch repair which is larger than required in order to repair the actual defect. The machine may therefore use more energy and more repair materials than is necessary to repair the defect and this has associated cost implications.

The present invention seeks to address one or more of the problems associated with conventional repair machines for repairing defects in a road surface.

Summary of the Invention

According to a &st aspect, the present invention provides a defect surveying system for surveying a defect in a road surface, comprising: a pressure sensor for determining occurrences of voiding and/or high water pressure at one or more locations within a defect in a road surface, in which the pressure sensor comprises an elongate shaft which is shaped and dimensioned to be received within a hole provided by a road surface, and in which the pressure sensor further comprises at least one pressure isolated pressure sensing element located on or adjacent the shaft, and in which the at least one pressure isolated pressure sensing element is arranged in use to measure the air and/or water pressures within the adjacent region of the defect.

The pressure sensor may comprise a plurality of spaced apart pressure isolated pressure sensing elements.

The at least one pressure sensing element is preferably moveable with respect to the elongate shaft.

The at least one pressure sensing element is preferably moveable in a direction extending substantially parallel to the longitudinal axis of the elongate shaft.

Each sensing element is arranged in use to be in communication with an individual air and/or water supply to allow individual control of the air and/or water supply to each sensing element.

The surveying system may further comprise a mobile topographic scanner for measuring and/or mapping a defect in a road sinface.

The topographic scanner may comprise a triangulating laser measuring head arranged in use to determine profile measurements of a defect within a road in a direction extending transverse to the direction of movement of the topographical scanner.

The surveying system may further comprise an endoscopic inspection system shaped and dimensioned to be received within a defect, in which the endoscopic inspection system is arranged in use to provide static and/or visual image capture.

According to a further aspect, the present invention provides a repair system for repairing a defect in a road surface comprising at least one thermocouple sensor arranged in use to be located at or adjacent one or more of the base and/or at least one boundary and/or the surface of the defect prior to introducing repair material into the defect.

The repair system may further comprise an array of heating elements arranged in use to be moveable relative to an exposed surface of a repair material located within the defect, in which each heating element within the array is individually controllable to deliver a predetermined heating pattern to the repair material.

The array may further comprise one or more temperature detection system comprising one or more of: radiant point infrared thermometer and/or digital infrared imaging array camera.

The temperature detection system may be arranged in use to be located adjacent and/or spaced apart from one or more heating elements. The array of heating elements is preferably arranged to be moveable across the surface of the repair material in a direction of motion. The temperature detection system is preferably arranged in use to be located adjacent and/or behind one or more heating elements with respect to the direction of motion of the array.

The heating elements may be arranged in use such that the heat and/or the transit speed of one or more of the heating elements within the array is automatically and independently variable depending on data obtained from one or more of the temperature detection system.

According to a further aspect, the present invention provides a method for surveying a defect in a road surface comprising: a) using a mobile topographical scanner to survey the defect; and/or b) drilling one or more holes into the road surface within or adjacent the defect, inserting: i) an endoscopic inspection system into one or more of the holes, and using the endoscopic inspection system to obtain depth information together with static and/or video based images; and/or ii) a pressure sensor comprising an elongate shaft shaped and dimensioned to be received within the hole into one or more of the holes, in which the pressure sensor further comprises at least one pressure isolated pressure sensing element located on or adjacent the shaft, and using the pressure sensor to obtain information about voiding and/or water pressure issues within or adjacent die defect.

According to a further aspect, the present invention provides a method for repairing a defect in a road surface comprising one or more of: a) positioning one or more thermocouple sensors at one or more of the base, the boimdary and/or the surface of the defect before the defect is filled with repair material; b) filling the defect with repair material; and c) positioning an array of heating elements adjacent to and/or moving the array relative to the exposed surface of the repair material, in which each heating element within the array is individually controllable to deliver a predetermined heating pattern to the repair material; in which information obtained from the one or more tiiermocouple sensors is used to adjust the heating pattern of the array of heating elements to provide optimum heating of the repair material.

The method of repairing the defect may further comprise excavating one or more portions of the road surface at or adjacent the defect in response to information obtained from the pressure sensor and/or the endoscopic inspection system and/or the mobile typographical scanner of the surveying system described herein.

Brief Description of the Drawings

Embodiments of the invention will now be described, by way of example only, and with reference to the accompanying drawings, in which:

Figure 1 illustrates an exploded view of a pressure sensor of the defect surveying system according to one embodiment of the present invention;

Figure 2 illustrates the pressure sensor of Figure 1 being used to determine occurrences of voiding and/or high water pressure at multiple locations within a defect in a road;

Figure 3 illustrates a mobile topographical scanner of tiie pot hole surveying system according to one embodiment of the present invention;

Figure 4 illustrates the results obtained by the topographical scanner of Figure 3 when scanning a defect in a road surface;

Figure 5 illustrates a schematic of the operation of the surveying and repair system of the present invention;

Figure 6 illustrates a cross-sectional view of a repair system according to one embodiment of the present invention comprising an array of heating elements; Figure 7 illustrates an exploded view of the repair system of Figure 6.

Detailed Description of the Invention

As shown in Figure 1, the surveying system comprises a pressure sensor 1 for determining occurrences of voiding and/or high water pressure at multiple locations within a defect in the road surface. The pressure sensor 1 comprises an elongate shaft 2 having a substantially circular cross-section. The elongate shaft 2 is hollow and provides a central bore 3 extending fiOm a first end 4 of the shaft 2 to the second end 5 of the shaft 2. The first end 4 of the shaft 2 comprises a threaded portion to threadingly engage a threaded nut 12.

The pressure sensor 1 is dimensioned to be received widiin holes made in or adjacent the defect in the road. Typically, in use the operator drills holes having diameters in the range of between 15mm and 20 mm. The pressure sensor 1 therefore has a cross-sectional diameter of less than the diameter of the holes into which it is to be inserted.

The pressure sensor 1 comprises three pressure isolated pressme sensing elements 6 located on the shaft 2. The sensing elements 6 are spaced apart from each other in a direction extending substantially parallel to the longitudinal axis of the shaft 2.

Each pressure isolated pressure sensing elements 6 is arranged to measure local air and/or water pressures in the adjacent portion of ground within the adjacent section of the hole.

The pressure sensor 1 may comprise any suitable number of pressure sensing elements 6 depending on the requirements for the sensor 1. For example, the pressure sensor may comprise a single pressure sensing element or a plurality of pressure sensing elements. Each pressure sensing element 6 comprises piezoelectric film 17 surrounded by a perforated surround 18.

Although Figure 1 shows the sensing elements 6 as being equally spaced apart from each other along the shaft 2, it is to be understood that the sensing elements 6 may be arranged in any suitable configuration and with any suitable spacings between adjacent sensing elements 6 depending on the particular requirements for surveying the hole.

The sensing elements 6 are permanently fixed in a predetermined configuration to the elongate shaft 2 of the pressure sensor 1. It is however to be understood that one or more of the sensing elements 6 may be moveable relative to the shaft 2. For example, one or more of the sensing elements may be displaceable along the length, in a direction extending substantially parallel to the longitudinal axis, of the shaft 2.

The at least one pressure sensing element may, be releasably attached to the elongate shaft. The elongate shaft may comprise at least one, for example a plurality of attachment features for releasable attachment to one or more pressure sensing elements. The attachment features may be spaced apart from each other along the shaft, for example along the length of the shaft. The attachment features may be spaced apart circumferentially around the shaft. The number and/or location of pressure sensing elements may therefore be varied as desired depending on the properties of the defect to be surveyed.

The pressure sensor 1 further comprises connection tubing 7 to individually connect air and/or water feeds (not shown) to each sensing element 6. The connection tubing 7 is received within and extends through the central bore 3 of the shaft 2.

The pressure sensor 1 further comprises electrical coimecting wires 8 for forming electrical connections to the sensing elements 6, allowing air and/or water to be introduced into the road formation local to their vertical position. The electrical connecting wires 8 are received within and extend through the central bore 3 of the sensor 1.

Although the embodiment of the pressure sensor 1 illustrated in Figure 1 shows that the central bore 3 is shaped and dimensioned to receive connection tubing 7 and connecting wires 8, it is to be understood that the tubing 7 and wires 8 may be located in any suitable location. For example, one or more of the connection tubing 7 and the connecting wires 8 may extend along the external surface of the shaft 2, for example within one or more grooves extending along the external surface of the shaft 2. The pressure sensor 1 may comprise a solid elongate shaft and may not provide a hollow central bore. For example, the elongate shaft may comprise a central bore which is at least part filled with resin or other solid forming liquid to provide a more robust shaft.

Figure 1 illustrates the pressure sensor 1 as having an elongate shaft having a substantially circular cross-section. It is however to be understood that the cross-section of the elongate shaft may have any suitable shape. A compressible sealing ring 13 is located at each end of the pressure sensing element 6. Spacers 14 are provided between die compressible sealing rings 13 of adjacent pressure sensing elements 6.

With reference to Figure 2, a small vertical hole 10 is drilled into the road surface to a depth typically in the range of fiom about 200 nun to about 400 mm. The depth of the hole 10 wiU depend on the total thickness of the road formation down to its sub-base. The hole 10 typically has a cross-sectional diameter in the range of from 15 nun to about 20 mm. The holes are preferably prepared within or adjacent the defect, such as for example a pot hole, in the road surface.

The hole is drilled so that the dimensions of the hole are sufficient to receive an endoscopic inspection system 30 and a pressure sensor 1 as illustrated in Figure 1.

The endoscopic inspection system 30 is inserted into hole 10 and is arranged to provide static and/or video based image capture. The endoscopic inspection system preferably comprises one or more encoders located at one or more reference points. The endoscopic inspection system (s) is arranged and located to facilitate synchronisation of the images obtained by the endoscopic system with the depth within the hole. The signals recorded hy the endoscopic inspection system may be interpreted using image processing methods and software to provide high level information on the material type, thickness and condition of die construction layers of the road. Such software discriminates boundaries, particle identification, texture, solid-binder ratio, voiding, cracks and other features that are pertinent to the strength and durability of the road construction and the repair strategy and prognosis for the defect.

The endoscopic inspection system 30 is removed and the pressure sensor 1 is inserted into the hole 10. After insertion, the locking nut 12 at the first end 4 of the shaft is tightened. The sealing elements 13 are vertically compressed and expand sideways (as shown in Figure 4) to make a sealing contact widi die walls of die hole 10. This isolates each sensing element 6 so that it reads the pressure oidy within the adjacent region, i.e. only measuring the pressure over the height of that pressure sensing element 6. Air and/or water feed 7 may then be individually introduced to each of the sensing elements 6 to determine occurrences of voids and/or water pressure issues in the corresponding adjacent portion of ground. The arrangement allows voiding and/or water pressure issues to be investigated through the complete depth of the road formation. This information is valuable for understanding the condition of the road formation adjacent to the defect and may be used to decide the extent of the area requiring repair, beyond the visual boundary of a defect.

Outwards horizontal arrows in fig 4 show the rings expanding under the action of the nut being tightened (arrow downwards at top of unit).

Furthermore, as the sensing elements 6 in one embodiment are moveable relative to the shaft 2 of the pressure sensor 1, the present invention provides a pressure sensor 1 which is able to investigate occurrences of voids and/or water pressure issues at one or more predetermined positions within the ground as desired.

With reference to Figure 3, the surveying system 100 may further comprise a mobile topographic scanner 20 for measuring and/or mapping a defect in a road surface, such as for example a pot hole. The topographic scanner 20 is located on a topographic scanner support 21.

The topographic scanner may for example be releasably mounted on the topographic scanner support. The topographic scanner support is moveable with respect to the defect. The topographic scanner support comprises a pair of wheels in which each wheel is arranged in use to be located on an opposing side of the defect. It is to be imderstood that die topographic scanner may not be mounted on a support. It is also to be imderstood that the scanner support may or may not comprise wheels. The scanner support may comprise any suitable number of wheels depending on the requirements.

The topographic scanner 20 comprises a triangulating laser measuring head adapted to measure and obtain data relating to the profile measurements of the defect 24 in the road. The topographic scanner 20 is moved in a direction across the defect in the road surface. The triangulating laser measuring head is arranged to determine and obtain profile measurements of a defect in a direction transverse to the direction of movement of the topographical scanner 20 across the road surface.

The topographical scanner 20 may be manually driven and steered over the defect in the road surface. Alternatively, the topographical scanner may be automated and may be guided and moved over the defect in the road surface with the aid of a computer.

The system 100 further comprises an encoder 26 located in one or more predetermined position(s) on the scanner support to provide a reference point for the results of the topographical scanner 20. The system may include any suitable number of encoders, such as for example a plurality of encoders. The encoder(s) may be located in any suitable position. As shown in Figure 4, the encoder is located on the axel of one of die wheels. The use of one or more encoders helps to improve the reliability of the topographical map of the defect. Figure 4 illustrates the results obtained by the topographical scanner using encoder 26 as a reference point. The position of the encoder 26 is marked “X”, lateral positions marked ‘Ύ” at which the depth of the road surface is marked “Z”.

Data from one or more of the topographical survey, endoscopic inspection and/or pressure measurement are used to define the optimum repair conditions for the defect. This information is fed into the controller of the repair system described herein.

In the UK, asphalt road is constructed in layers, which are typically a 100m-250mm base layer, 50mm-100mm binder layer and 20mm-50mm surface coarse layer. The present invention provides a survey system which first surveys the defect and then adjust the repair system such that the depth of the repair is decided according to the thicknesses and condition of these layers. The repair is not carried out merely as a consequence of the apparent depth of the defect in the surface. Furthermore, the cross-sectional dimensions and shape of the repair area relate to the defect and is not defined by the size and shape of die heater of the repair system. The present invention therefore repairs defects in an economical manner, without using excessive material which leads to increased energy and repair costs.

Figure 5 illustrates a schematic of the operation of the surveying system and repair system, according to one embodiment of the present invention. It can be seen from Figure 5 that the surveying system 100 comprises a controller 202. The controller 202 comprises a processor 204 that cedculates the volume of the defect, such as for example a pot hole, and the volume of repair material required to form the road repair, allowing for both heating and subsequent compaction, as a result of information obtained from the surveying and/or repair systems.

After analyzing the data obtained from one or more of the components of the surveying system, it may be advantageous to remove additional road material adjacent to the defect in order to form an excavation to a predetermined size, shape and/or depth which is different to that of the original defect. For example, it may be advantageous to excavate at the site of the defect in order to improve the quality of the repair based on the outcomes of the survey. Removal of such material may be aided by softening the repair area by the application of heat. Heat may be applied to the area by a heating array as discussed herein in relation to the repair system.

References herein to the term “defect” are intended to include excavated sites which have been prepared as a response to information obtained from the surveying system.

Excavated road material is preferably not immediately recycled because it is not feasible to predict its performance as repair material. Old road surfacing may contain tar based materials, for example, which are not suitable for repairing asphalt roads. Such immediate recycling, without technical evaluation and reprocessing into a suitable repair material is one of the causes for early failure with current pot-hole repair methods.

Figures 6 and 7 illustrate a repair system according to one embodiment of the present invention. The repair system 300 comprises a thermocouple sensor 302 which is located within the defect 304. The sensor 302 is placed at the base 306 of the defect 304 prior to introduction of repair material (not shown) into the defect 304. Although Figure 6 shows the repair system as comprising a single thermocouple sensor 302 it is to be understood that the repair system can comprise any suitable number of sensors. The sensors 302 may be located in any suitable location within or adjacent the defect, for example at the base, at the boundary, at the surface adjacent the defect.

The sensor(s) 302 are located in or adjacent the defect in order to provide temperature measurement at one or more particular locations to provide information relating to the quality of the repair at for example boundaries between the defect and the repair material. The thermocouple sensor(s) are preferably arranged in use to remain in position during and optionally after the repair material has been introduced into the defect so as to detect the temperature at the or each location during the repair process.

The sensor(s) is in communication with a controller 303. The controller 303 is programmed to trigger an alarm when the temperature of the sensor(s) reaches a predetermined maximum level.

The present invention provides a repair system which is able to monitor the buried temperature at boundaries formed between the defect and the repair material. Boundaries between the defect and the repair material are often the regions where premature repair failure initiates. Failure is considered to be as a result of heat loss and insufficient heating of the repair material adjacent to the boundary. The present invention therefore advantageously provides a repair system which is able to accurately monitor the temperature at the repair material-defect boundary and adjust the heating pattern accordingly. The present invention is therefore able to provide a repair system having a reduced failure rate of the repair.

The thermocouple sensor(s) 302 remain in their location during filling of the defect with repeiir material. Preferably the thermocouple sensor(s) remains in position during heating of the repair material. The thermocouple sensor 302 are small in dimension and comprise thin leads. As a result, the sensors 302 can be removed at the required time, for example after the defect has been repaired, with minimal disturbance to the repair site. The sensors can be removed before or after compaction.

The thermocouple sensors of the repair system may be used to obtain temperatures at the surface, base and/or boundary of the repair material - defect in closed loop control, which eliminates the influence of boundary conduction and unpredictable cooling effects due to wind.

The repair system may further comprise one or more dielectric sensor in order to sample the repair quality. A first part of a dielectric sensor may be placed on the exposed surface of the defect prior to filling with repair material and the second part on the repair fill material after filling. The one or more dielectric sensor may be placed in any suitable location. Dielectric values may then be measured providing an indication of important mechanical properties relating to the formed repair. The dielectric sensors may be composed of foil sheets connected by wires to dielectric measurement equipment.

Once the thermocouple sensor(s) and/or dielectric sensor(s) are in the predetermined locations within the defect, the defect may be filled with suitable repair material. For example, the defect may be filled with appropriate asphaltic based road surfacing. For small repairs, of the order of Im x Im plan and 0.025m to 0.050m depth, it is preferable, for durability of the repair, to not immediately recycle material removed from the road defect. In such cases, suitable material would be brought to the repair location. For larger repairs, which can be supported by local testing of materials removed from the damage road surface, partial recycling of excavated materials may be appropriate.

After the repair material has been introduced into the defect, the repair material is heated. The repair system, as shown in Figures 6 and 7, comprises a linear array of heating elements 400. The example repair system of Figure 6 comprises four spaced apart heating elements 400 arranged in a row. It is however to be understood that the repair system may comprise any suitable number of heating elements 400. The heating elements may be arranged in any suitable configuration within an array. For example the array may comprise more than one row of heating elements 400.

The repair system is arranged such that the heating elements 400 are collectively passed over the placed repair material. Each heating element 400 is arranged to be independently controlled in order to deliver an accurate optimised heating pattern of the placed fill material, according to the changing depth, plan shape and dimensions of the repair area as determined by the surveying system of the invention. Heating and/or the transit speed across the repair area of each heating element can varying automatically according to the heating requirement, allowing for varying depth of the placed fill material. For example, data obtained from the surveying system, for example from one or more of the pressure sensor 1, the topographical scanner and/or the endoscopic inspection system, and/or data obtained from the thermocouple sensor(s) may be used to by the repair system to control and/or adjust the pattern of heating performed by each heating element. Once the temperature of the thermocouple sensor(s) reaches a predetermined maximum temperature the controller 303 may switch off one or more of the heating elements within the array. The controller 303 may trigger an audible or visual alarm when the maximum temperature has been recorded by the sensor(s). A similar audible or visual prompt may be issued when any part of the repair reaches a particular desired temperature. The heating elements may be individually switched on or off and/or operated to deliver any desired pattern of heating to the road surface. The heating elements may be individually controlled in order to compensate for heating loss at for example boimdaries between the repair material and the defect surface. Accurate control of the heating elements may be achieved by pre-mixing the gas fuel with air.

The heating elements are preferably infrared heating elements.

The array of heating elements is preferably lightweight, compact and makes it easy to transport and deploy repair system. The heating elements may be located on a heating support 402. Each individual heating element may be moveable with respect to the heating support 402. As shown in Figure 7, each heating element is connected to a separate adjustment feature 403. Each heating element, together with the corresponding adjustment feature 403, may be independently and manually slideable with respect to the heating support 402 by operating and moving adjustment features 403 into the desired position. Movement of the or each heating element with respect to the heating support may be automated.

One or more of the heating elements may be removably attached to the heating support 402. The heating support may comprise a plurality of spaced apart attachment features for removable attachment to the heating element(s). One or more of the heating elements may be attached to an attachment feature of the heating support in the desired location for the heating pattern. One or more of the heating elements may be removed from and/or repositioned on an attachment feature of the heating support in the desired location for the heating pattern. The number of heating elements on the heating support may vary depending on the desired heating pattern. For example, additional heating elements may be added to the heating support or removed from the heating support in order to provide the desired heating pattern.

The individual heater elements may have any suitable dimensions. The plan or transverse dimensions of individual heater elements may vary and are typically in the range of between 200mm x 200mm to about 400mm x 400mm. The terms plan or transverse dimension(s) are used herein to refer to the dimension of the defect or the heater when in position to repair a defect when viewed from above.

The array may comprise heater elements of varying sizes. Preferably, die array comprises heater elements of uniform size. The individual heater elements may have any suitable shape. For example, the individual heater elements may have a square or rectangular cross-section. The array may comprise heating elements of varying shapes. Preferably, the heating elements of the array are all of the same shape.

Each heating element has its own precise temperature control to apply any constant or variable pattern of heating as desired for a particular section of the repair area. The heating support 402 comprises two spaced apart pairs of wheels 405 to enable the machine to be moved across the repair area. It is to be understood that the heating support may comprise any suitable number of wheels to enable the machine to be moved across the repair area. The heating support 402 may be moved manually across the repair area, or movement of the heating support 402 may be automated.

As the machine traverses the repair area, individual heating elements are automatically switched on or off or temperature adjusted by the controller according to the changing width of the repair and influences of changing climatic conditions. Such automatic adjustment may also occur due to changing depth within the repair, such topographical information existing from the previous automatic survey of the defective area, or due to temperature measurements obtained from thermocouple sensors. Premature failure of repaired pot holes is known to be partially caused by inadequate heating of the repair material used to fill the hole defect, especially at boundaries. Tbe temporarily placed thermocouples of the invention overcome this problem by feeding back to the heater control system the boundary temperature data.

The heating elements may be powered by any suitable power source. Preferably, the heating elements are powered by bottled liquid gas 406.

The repair system preferably comprises one or more radiant point infrared thermometers and one or more digital infrared imaging array cameras for measuring the complete temperature profile across at least one section of the repair, for example the corresponding section of the repair which is being heated by the heating elements, for example across the fiill width of the repair, immediately following the direction of movement of the heating element(s). The one or more radiant point infrared thermometers and one or more digital infrared imaging array cameras are preferably arranged to provide feedback and control to the heating provided by the repair system.

The array of heaters are mounted on a moveable heating support. The heating support may be arranged such that the array of heaters extend across the surface of the repair in a direction extending at an angle, for example substantially perpendicular, to the direction of movement of the heating support.

The controller of the repair system further comprises one or more motors and/or one or more encoders. The one or more motors and/or one or more encoders are preferably arranged to automatically control and/or monitor the transit speed of the heating support, and in particular the heating element(s), across the repair surface. The controller of the repair system is preferably arranged to use the data obtained from the thermocouple sensor(s) recording the surface temperature profile of the repair and/or the data obtained from the thermocouple sensor(s) recording the temperatures at the buried interfaces between the defect and the repair material to control and/or adjust the transit speed of the heating support carriage across the repair surface, and/or individually control and/or vary the temperature of each heating element to achieve optimum heating of the repair area. Control of the transit speed and/or temperature of the heating element(s) may be performed in a closed loop mann^ based on temperature information that affects the quality of the completed repair. The repair system of the present invention may therefore eliminate the adverse influence of the local climate. The influence of local climate may adversely affect the outcome as to the quality of the repair due to the uncompensated effects of ambient temperature and/or exposure of the repair area to wind. The controller may fiuther be arranged to exploit such logic as neural networks and/or fixzzy logic, using the data of heater element(s) setting and/or resulting temperature feedback. The repair system may further comprise a drive system, which may have a hand-held pendant command option, for unloading and reloading the repair system and/or positioning the repair system over the repair.

The surveying system and/or repair system of the present invention may be used to survey and/or repair a wide range of defects, in for example a road surface, having a variety of different sizes and/or shapes. For example, the system(s) of the present invention can be used to survey and/or repair defects having predominantly rectilinear or circular cross-sectional shapes.

The size of the defect which may be repaired by the repair system may be limited in only one direction in view of the adopted size of the repair system and/or the number of individual heating elements in the heating array of the system. The direction of motion of the heating system is preferably at an angle to, for example substantially perpendicular to, the directional alignment of the heating element(s) within the heating array. As a result, the repair system of the present invention may be used to provide a continuous repair of any desired length in the direction of motion of the heating system. The lateral dimension of the heating support, for example the dimension measured in a direction extending substantially perpendicular to the direction of motion of the system, may be fixed or may be adjustable in any manner according to the shape and/or dimensions of the road defect requiring repair.

The surveying and/or repair system of the present invention can, for example, survey and/or repair a small defect in a road surface having a maximum plan or transverse dimension of 0.2m. The surveying and/or repair system of the present invention can, for example, survey and/or repair a defect in a road surface having a maximum plan or transverse dimensions of 2m by 4m. The heating support is preferably arranged such that the array of heating elements, for example the linear array of heating elements, extends across the defect in a direction corresponding to the smaller dimension of 2 m. The heating support is preferably arranged such that the direction of movement is predominantly aligned with the direction of the greater dimension of 4 m of the defect.

In one embodiment, the repair system uses real-time infrared thermographic imaging together with buried thermocouple sensors. The repair system of the present invention therefore provides for a significant improvement in the means of controlling heating of the repair material and thus achieving superior repairs with increased lifespan. After completion of the heating stage, the buried thermocouples may be removed from the repair site with little disturbance to the repair material.

Immediately following the heating stage by the repair system, the heated repair material may be compacted. The heated repair material may be compacted using any suitable means. For example, the heated repair material may be compacted using a manually steered surface roller. This is done by making several passes of the compaction roller over the filled excavation. During and/or after this compaction process, the buried thermometers can provide information on the cooling of the placed fill. Surface temperatures may also be sampled for quality control purposes. After completion of compaction, the buried thermocouples are removed, causing minimum disturbance of the compacted fill. Further compaction may occur where the thermocouple leads are drawn out for the compacted fill.

Data obtained by any component of the surveying and/or repair system of the present invention may be communicated historically or at real time by means of SMS and/or internet to remote monitoring points. GPS is incorporated, which allows the data obtained by one or more components of the surveying system to be located and time stamped. Persons remote to the repair site can have access to such data as time, loeation, road porosity and condition with depth, defect and repair shape, size, depth and volume, heating pattern delivered, temperature history, surface and buried temperatures, mechanical properties based on dielectric constant, and any malfunctions.

The surveying system and repair system may be provided as an integrated or unitary system. The surveying and/or repair system may be manually operated or may be automated. The present invention provides a surveying system which is capable of surveying and characterising the road pavement defect prior to repair. The present invention provides a surveying system which is capable of configuring a repair system based on the outcomes of survey and characterization. The present invention provides a repair system which is capable of delivering an accurate optimized distribution of heat to the repair using closed loop temperature sensor feedback for the surface and hidden boundary locations within the repair. The present invention provides a surveying system and/or a repair system which is capable of performing individual single repairs to defects of varying cross-sectional dimensions, such as for example from 0.2 m x 0.2 m plan size to repairs of unlimited length and 2m or more width. The present invention provides a repair system which is capable of sensing important material properties of the compacted defect fill material to improve the repair. The present invention provides a surveying system and/or a repair system capable of communicating via the internet information on location, time and real-time system status of the repair machine (on/off, temperature, duration etc). The present invention provides a surveying system and/or repair system which is compact, lightweight and capable of being transported to the repair location on a road trailer that can be towed by a car or other small vehicle. As a result of the smaller dimensions, die systems of the present invention may be used in restricted locations, for example, in narrow lanes without fuU closure of the road.

Although reference has been made to the surveying system and the repair system, it is to be understood that these systems may be provided as separate units or may be provided within a single unit. The present invention may therefore provide an integral surveying and repair unit comprising the features discussed herein in respect of the surveying system and the repair system.

Although aspects of the invention have been described with reference to the embodiment shown in the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiment shown and that various changes and modifications may be effected without further inventive skill and effort.

Claims

1. A repair system for repairing a defect in a road surface, the defect defining a surface for repair and a recess to receive repair material during a repair process, the repair system comprising: i. a thermocouple sensor for location in or adjacent the defect surface and adapted to monitor temperature at a boundary between the defect surface and the repair material before and optionally diiring repair of the road surface; and ii. a controller, in communication with the thermocouple sensor, wherein the thermocouple sensor is operable to provide temperature data to the controller and the controller is operable to receive and monitor temperature data from the thermocouple sensor.

2. A repair system according to claim 1, wherein the repair system comprises a plurality of thermocouple sensors, each thermocouple sensor arranged for location in or adjacent the defect surface and in communication with the controller.

3. A repair system according to claim 1 or claim 2 wherein the controller is operable to trigger an alarm when a predetermined temperature is detected by one or more of the thermocouple sensors.

4. A repair system according to any preceding claim, further comprising one or more radiant point infrared thermometers and/or digital infrared imaging array cameras operable to measure a temperature profile across at least a section of the exposed surface of the repair material located within the recess.

5. A repair system according to any preceding claim further comprising an array of heating elements arranged in use to be moveable relative to the exposed surface of the repair material located within die recess, each heating element being individually controllable such that the array is operable to deliver a predetermined heating pattern to the repair material.

6. A repair system according to claim 4, wherein each heating element within an array is independently moveable relative to the exposed surface of die repair material located within the recess.

7. A repair system according to any preceding claim, wherein the array further comprises one or more temperature detection systems, each temperature detection system comprising one or more of: a radiant point infrared thermometer and a digital infrared imaging array camera, wherein each temperature detection system in communication with the controller and operable to provide temperature data to the controller.

8. A repair system as claimed in any preceding claim, wherein the temperature or speed of movement of one of more of the heating elements within an array is automatically and independently variable by the controlled in dependence upon the temperature data received by the controller from the temperature detection system.

9. A method for repairing a defect in a road surface, the defect defining a surface for repair and a recess to receive repair material during a repair process, the method comprising: 1. positioning a thermocouple sensor in or adjacent the defect surface; 2. providing a controller in communication with the thermocouple and operable to receive temperature data from the thermocouple sensor; 3. supplying repair material into the recess; 4. positioning an array of heating elements adjacent the exposed surface of the repair material and in communication with the controller; 5. providing a predetermined heating pattern to the repair material in dependence upon temperature data received by the controller from the thermocouple sensor.

10. A method according to claim 9, the method further comprising carrying out steps i. to iv. prior to steps a) to e): i. drilling a hole in the road surface within or adjacent the defect: ii. inserting an endoscopic inspection system into the hole and using the endoscopic inspection system to obtain depth information together with static based images or video based images or static and video based images; iii. inserting the elongate shaft of a pressure sensor into the hole, the elongate shaft being shaped and dimensioned to be received with a correspondingly shaped and dimensioned surface, and using one or more pressure sensing elements located on or adjacent the shaft to measure the air and/or water pressures within the hole; and iv. excavating a portion of the road surface at or adjacent tiie defect in dependence upon data received from the pressure sensor and/or the endoscopic inspection system.

11. A method according to claim 10, further comprising using a mobUe topographical scanner to survey the defect, the excavation of a portion of the road surface at or adjacent the defect being dependent upon data received from the mobile topographical scanner and upon data received from one or both of the pressme sensor and endoscopic inspection system.