System and method for preventing accumulation of meltable precipitation on a given surface

Abstract

There is described a system for preventing accumulation of meltable precipitation. The system generally having an electrode assembly having: a base electrode; an enclosing electrode having an upper portion spaced away from the base electrode, and a wall portion extending from a periphery of the upper portion to a distal edge surrounding the base electrode; the enclosing electrode and base electrode defining a volume extending within the electrode assembly; a gap between the distal edge of the wall portion and the base electrode; and a body of concrete within the volume of the electrode assembly; and a voltage source having a first conductor electrically connected to the enclosing electrode and a second conductor electrically connected to the base electrode.

Description

SYSTEM AND METHOD FOR PREVENTING ACCUMULATION OF MELTABLE PRECIPITATION ON A GIVEN SURFACEFIELD

[0001] The improvements generally relate to concrete slabs and more specifically to heating or preventing accumulation of meltable precipitation such as snow, ice, graupel and / or hail on such concrete slabs.BACKGROUND

[0002] Accumulation of snow or ice on infrastructures such as roads or bridges is usually undesirable. To remove such accumulation of snow or ice, it was known to spread salt or other de-icing agents on infrastructures in order to melt the snow or ice. Additionally or alternately, winter service vehicles can mechanically remove snow or ice from some infrastructure. However, these techniques can be impractical in at least some situations. For instance, salt can be inefficient below a given temperature, and can damage concrete structures in the long run, thereby shortening their expected service life. Moreover, winter service vehicles may not be sized to reach all areas of the infrastructures that need snow or ice removal, and can cause wear and tear to the areas of the existing infrastructures that they do reach. As a solution, PCT Patent Publication no WO 2020 / 097718 disclosed a concrete slab across which an array of parallel, horizontally-oriented conductive bars are distributed. When an electrical current was circulated between these bars, the surrounding concrete slab heated which could melt any precipitation accumulated on a top surface thereof. However, these existing heated concrete slabs can be inefficient in terms of electricity costs and uneven current distribution. Additionally, they are known to provide warmer and colder areas, which in turn require more energy to heat the colder areas beyond the melting point while the other areas would remain warmer than required. Although such ice removal techniques are satisfactory to a certain degree, there remains room for improvement.SUMMARY

[0003] It was demonstrated that the solution described above was satisfactory in a real life setting. However, there was a motivation to keep the electrical current circulating between the bars at to low voltages, for safety purposes for instance, which required costly very highconductivity interconnects, 4:1 transformers, rectifiers and associated cabling to reduce the standard 120 V AC line to 30 V.

[0004] Embodiments presented herein may alleviate at least some of the drawbacks of the above-mentioned ice and snow removal techniques. Such embodiments may include a tilelike electrode assembly having a base electrode resting within an infrastructure, an enclosing electrode having an upper portion exposed to meltable precipitation, and a wall portion extending from a periphery of the upper portion to a distal edge surrounding the base electrode, and a body of concrete filling a volume extending between the base electrode and the enclosing electrode. The concrete filling the electrode assembly can be provided with an electrically resistive concrete which would conduct electricity, but much less than the electrode assembly. As such, when an electrical current is applied between the base electrode and the enclosing electrode, electrical paths are formed between the base electrode and an interior surface of the enclosing electrode, and across the body of concrete. This construction can impede any electrical paths beyond the enclosing electrode which could otherwise escape from the electrode assembly, thereby potentially preventing stray currents. Accordingly, the costly 4:1 transformers and rectifiers can be omitted as the standard 120 AC line can be used directly. In some embodiments, the neutral line of the standard 120 AC line source is connected to the enclosing electrode whereas the phase (or live) line of the standard 120 AC line source is connected to the base electrode. Accordingly, the electrode closer to the meltable precipitation is connected to a neutral line or ground, which is further adding to the safety of the overall system. Moreover, since the proposed tile-like electrode assembly uses AC voltage, the electrical field is reversed periodically, and thus potential oxidation and reduction cycles counteract each other. The use of the AC voltage reduces the chances to develop electrode polarization which would increase the contact resistance of the electrodes and decrease the current flow. It also protects the electrodes from oxidation processes that could degrade the electrodes over time. Moreover, it is intended that the proposed tile-like electrode assembly can advantageously increase the repairability of any infrastructure including such tile-like electrode assemblies. The proposed tile-like electrode assembly can be replaced individually if they fail for one reason or another. As such, the modularity of the proposed tile-like electrode assembly can be especially convenient in some applications.

[0005] In accordance with a first aspect of the present disclosure, there is provided a system for preventing accumulation of meltable precipitation on a given surface, the system comprising: an electrode assembly having: a base electrode; an enclosing electrode having an upper portion spaced away from the base electrode, and a wall portion extending from a periphery of the upper portion to a distal edge surrounding the base electrode; the enclosing electrode and base electrode defining a volume extending within the electrode assembly; a gap between the distal edge of the wall portion and the base electrode; and a body of concrete within the volume of the electrode assembly; and a voltage source having a first conductor electrically connected to the enclosing electrode and a second conductor electrically connected to the base electrode, the voltage source operable to circulate an electrical current from the base electrode to the enclosing electrode and across the body of concrete, to melt the meltable precipitation when the meltable precipitation is in thermal contact with the upper portion of the enclosing electrode.

[0006] Further in accordance with the first aspect of the present disclosure, the voltage source can for example be a high-voltage source, the electrical current having a voltage value ranging between 60 V and 1 000 V.

[0007] Still further in accordance with the first aspect of the present disclosure, the voltage source can for example be an alternating current (AC) voltage source, the electrical current being an AC current.

[0008] Still further in accordance with the first aspect of the present disclosure, the first conductor can for example be a neutral line and the second conductor is a phase line.

[0009] Still further in accordance with the first aspect of the present disclosure, the electrode assembly can for example have a layer of protective material on the electrode assembly.

[0010] Still further in accordance with the first aspect of the present disclosure, the protective material can for example include at least one of a thermally insulating material, an electrically insulating material, and a mechanically protective material.

[0011] Still further in accordance with the first aspect of the present disclosure, the protective layer can for example include at least one of an epoxy, a polystyrene polymer and a high- performance concrete.

[0012] Still further in accordance with the first aspect of the present disclosure, the layer can for example have a top surface portion deposited on the upper portion of the enclosing electrode.

[0013] Still further in accordance with the first aspect of the present disclosure, the layer can for example enclose the upper portion of the enclosing electrode, the wall portion of the enclosing electrode and the base electrode.

[0014] Still further in accordance with the first aspect of the present disclosure, the layer can for example have a base portion on which the base electrode sits.

[0015] Still further in accordance with the first aspect of the present disclosure, the base portion of the layer can for example extend from a periphery of the base portion to a distal edge surrounding the wall portion of the enclosing electrode.

[0016] Still further in accordance with the first aspect of the present disclosure, the periphery of the enclosing electrode can for example have a parallelogram shape.

[0017] Still further in accordance with the first aspect of the present disclosure, the base electrode can for example be parallel to the upper portion of the enclosing electrode.

[0018] Still further in accordance with the first aspect of the present disclosure, the base electrode and the enclosing electrode can for example have a plurality of through apertures.

[0019] Still further in accordance with the first aspect of the present disclosure, the plurality of through apertures can for example have evenly distributed on the base electrode and the enclosing electrode.

[0020] Still further in accordance with the first aspect of the present disclosure, the base electrode and the enclosing electrode can for example be made of electrically conductiveconcrete, the electrically conductive concrete having a lower electrical resistance than an electrical resistance of the concrete of the body.

[0021] Still further in accordance with the first aspect of the present disclosure, the system can for example further comprise a controller having a processor and a non-volatile memory having stored thereon instructions which when executed by the processor operate the voltage source.

[0022] Still further in accordance with the first aspect of the present disclosure, the system can for example further comprise a precipitation detector communicatively coupled to the controller, the controller receiving a precipitation indicator from the precipitation detector and activating the voltage source based on the precipitation indicator.

[0023] Still further in accordance with the first aspect of the present disclosure, the base electrode can for example have a first surface area, and the upper portion of the enclosing electrode has a second surface area greater than the first surface area of the base electrode.

[0024] Still further in accordance with the first aspect of the present disclosure, the concrete of the body can for example have a resistivity value ranging between about 500 and 100,000 Q'cm, and most preferably between about 2,000 and 80,000 Q cm.

[0025] Still further in accordance with the first aspect of the present disclosure, the concrete of the body can for example incorporate a plurality of electrically conductive particles distributed in the concrete of the body.

[0026] In accordance with a second aspect of the present disclosure, there is provided a method for melting accumulation of meltable precipitation on a given surface, the method comprising: applying an electrical current across an electrode assembly, the electrode assembly having a base electrode resting within an infrastructure, an enclosing electrode having an upper portion exposed to meltable precipitation, and a wall portion extending from a periphery of the upper portion to a distal edge surrounding the base electrode and forming a gap therearound, and a body of concrete within a volume extending between the base electrode and the enclosing electrode; said electrical current forming electrical paths extending between the base electrode and an interior surface of the enclosing electrode, and across thebody of concrete, thereby heating the body of concrete; and said heating including melting said meltable precipitation accumulating on the given surface.

[0027] Further in accordance with the second aspect of the present disclosure, said electrical current can for example be an alternating current, the base electrode receiving a phase line of the alternating current, and the enclosing electrode receiving a neutral line of the AC.

[0028] Still further in accordance with the second aspect of the present disclosure, the electrode assembly can for example include a plurality of identical electrode assemblies adjacent one another, the plurality of identical electrode assemblies heating the given surface upon said applying.

[0029] Still further in accordance with the second aspect of the present disclosure, the method can for example further comprise detecting that one of the plurality of identical electrode assemblies is defective; and replacing the one of the plurality of identical electrode assemblies with a working electrode assembly while the other ones of the plurality of identical electrode assemblies remain in position.

[0030] All technical implementation details and advantages described with respect to a particular aspect of the present invention are self-evidently mutatis mutandis applicable for all other aspects of the present invention.

[0031] Many further features and combinations thereof concerning the present improvements will appear to those skilled in the art following a reading of the instant disclosure.DESCRIPTION OF THE FIGURES

[0032] In the figures,

[0033] Fig. 1 is an oblique view of a system for preventing accumulation of meltable precipitation on a given surface, showing an electrode assembly having a base electrode, an enclosing electrode, and a body of concrete, in accordance with one or more embodiments;

[0034] Fig. 1A is a side elevation view of the system of Fig. 1 , taken along point of view 1A- 1 A of Fig. 1 , in accordance with one or more embodiments;

[0035] Fig. 2A is an oblique view of an example of an enclosing electrode and a base electrode, in accordance with one or more embodiments;

[0036] Fig. 2B is an oblique view of an electrode assembly incorporating the enclosing electrode and the base electrode of Fig. 2A, in accordance with one or more embodiments;

[0037] Fig. 3 is an oblique view of an example of an electrode assembly, shown with a first example of a protective layer surrounding the electrode assembly, in accordance with one or more embodiments;

[0038] Fig. 4 is an oblique view of an example of an electrode assembly, shown with a second example of a protective layer having a top portion surrounding an enclosing electrode, and a base portion on which the electrode assembly sits, in accordance with one or more embodiments;

[0039] Fig. 4A is a side elevation view of another example of an electrode assembly, shown with a third example of a protective layer covering exterior surfaces of the wall portion of the enclosing electrode and the base electrode, in accordance with one or more embodiments;

[0040] Fig. 5 is a graph showing surface and internal temperatures as a function of time for the electrode assembly of Fig. 4, in accordance with one or more embodiments;

[0041] Fig. 6 is a graph showing surface and internal temperatures as a function of power for the electrode assembly of Fig. 4, in accordance with one or more embodiments;

[0042] Fig. 7 is a schematic view of an example of a computing device of a controller, in accordance with one or more embodiments; and

[0043] Fig. 8 is a flow chart of an example of a method for melting accumulation of meltable precipitation on a given surface, in accordance with one or more embodiments.DETAILED DESCRIPTION

[0044] Fig. 1. shows an example of a system 100 for preventing accumulation of meltable precipitation on a given surface. As depicted, the system 100 has an electrode assembly 102,a voltage source 104 and a controller 106. As will be discussed below, the controller 106 can be omitted in some embodiments.

[0045] The electrode assembly 102 has a base electrode 108. An enclosing electrode 110 is also provided. As illustrated, the enclosing electrode 110 has an upper portion 110a spaced away from the base electrode 108. In the depicted embodiment, the upper portion 110a of the enclosing electrode 1 10 is parallel to, but spaced away from, the base electrode 108. The enclosing electrode 110 is provided with a wall portion 1 10b which extends from a periphery of the upper portion 110a to a distal edge 1 10c surrounding the base electrode 108 and forms a gap 1 14. It is noted that although they are spaced from one another, the enclosing electrode 110 and the base electrode 108 collectively define a volume which extends within the electrode assembly 102. The electrode assembly 102 further includes a body 116 of concrete extending within the volume of the electrode assembly 102.

[0046] It is intended that the body 116 of concrete is generally provided in the form of an electrically resistive concrete. In some embodiments, the concrete of the body 116 has an electrical resistivity value ranging between about 500 and 100,000 Q cm, and most preferably between about 2,000 and 80,000 Q cm. Typically, the electrically resistive concrete is not so resistive as to prevent electrical charges to circulate therethrough, but can still provide a heat generating resistive path between the base electrode 108 and the enclosing electrode 1 10. Concrete having such electrical resistivity values can be obtained by incorporating electrically conductive particles (e.g., metallic particles) in the fresh concrete mixture, to name one example. In certain embodiments, the difference of electrical resistivity values between the electrode assembly and the concrete of the body 116 can differ by more than one order of magnitude, and preferably two or more orders of magnitude. As such, the electrode assembly has an electrical conductivity value being much greater than an electrical conductivity value of the body 116 of concrete.

[0047] In the illustrated embodiment, the wall portion 1 10b extends perpendicularly relative to the upper portion 110a. Accordingly, for the gap 114 to be formed, the base electrode 108 has a smaller footprint than a footprint of the upper portion 1 10a. More specifically, the base electrode 108 has a first surface area, and the upper portion 110a has a second surface area which is greater than the first surface area. In some other embodiments, the wall portion 110bextends obliquely relative to the upper portion 110a, such as in a taper shape or an inverse taper shape. In these latter embodiments, the base electrode 108 can be smaller or larger in size than the upper portion 110a, as long as the gap 114 is formed around the base electrode 108. In any case, the periphery of the distal edge 110c of the wall portion 110b has a surface area larger than a surface area of the base electrode 108.

[0048] As shown, the voltage source 104 has a first conductor 120 which is electrically connected to the enclosing electrode 110, and a second conductor 122 which is electrically connected to the base electrode 108. During use, the voltage source 104 is operable to circulate an electrical current from the base electrode 108 to the enclosing electrode 110 and across the body 116 of concrete. The circulation of current can create dissipation of energy through ohmic losses and generate heat. As a result of the circulating electrical current, the body 1 16 of concrete will heat and thus melt any meltable precipitation accumulated on a top surface of the system 100. In some embodiments, the top surface can be a surface which is parallel and spaced apart from the enclosing electrode 110. However, in some other embodiments, the top surface can be part of the enclosing electrode 110.

[0049] The controller 106 is typically in wired or wireless communication with the voltage source 104, and / or with one or more sensor(s). The controller 106 has a processor, and a non-volatile computer memory having stored thereon instructions that when executed by the processor control the operation of the voltage source 104. In some embodiments, a first temperature sensor 124 is provided proximate to the upper portion 110a of the enclosing electrode 110, and / or a second temperature sensor 126 is provided within the body 116 of concrete. In these embodiments, the first and second temperature sensors 124 and 126 may be communicatively coupled to the controller 106 as well. As such, when the controller 106 determines that the system 100 is exposed to an environment prone to meltable precipitation, i.e., when the first temperature sensor 124 reads a temperature below the melting point, the controller 106 can activate the voltage source 104 and apply an electrical current between the enclosing electrode 1 10 and the base electrode 108.

[0050] In some embodiments, the voltage source 104 is a high-voltage source such as can be provided with a conventional power outlet. In these embodiments, the electrical current in these embodiments can be supplied from an electrical voltage source which ranges from about60 V to about 1 000 V, and most preferably between 120 V and 240 V. However, the electrical current can range between 120 V and 240 V, or exceed 240 V, depending on the embodiment. In the illustrated embodiment, power electronics 107 are electrically coupled to the voltage source 104 and to the controller 106. In embodiments where the voltage source 104 is a high- voltage source, the power electronics 107 can help reduce the voltage of the high-voltage source so that it can supply lower-voltage power to the controller 106 as well. The power electronics 107 can include, but are not limited to, transformer(s), rectifiers), converter(s), and the like.

[0051] Referring now to Fig. 1A, the voltage source is an alternating current (AC) voltage source 104 in this example. As such, the electrical current applied across the electrode assembly 102 is an AC current. In these embodiments, it was found preferable to connect the first conductor 120 to a neutral line of the AC voltage source 104 and the second conductor 122 to a phase line of the AC voltage source 104. As shown in this view, the electrical paths (showed in dashed lines) formed by the circulation of the electrical current across the electrode assembly 102 propagates from the base electrode 108 to the enclosing electrode 1 10. In this manner, the electrical paths remains inside the electrode assembly 102 in a manner analogous to a Faraday cage. As such, undesirable currents straying away from the electrode assembly 102 are prevented.

[0052] Fig. 2A shows an example of an enclosing electrode 210 and a base electrode 208 prior to their assembly. An example method of assembling the electrode assembly 200 is provided below for convenience. Fig. 2B shows the actual electrode assembly 200, with the body of concrete. As shown in this example, the enclosing electrode 210 and the base electrode 208 are both made of a similar electrically conductive material. For instance, metal such as stainless steel was used in this example. However, other electrically conductive materials can be used in some other embodiments. In this specific embodiment, the electrodes are made from metal sheet(s) that can be cut and folded into the enclosing electrode 210 and the base electrode 208. As such, the enclosing electrode 210 and the base electrode 208 can have a similar thickness. The enclosing electrode 210 and the base electrode 208 can have different thicknesses in some other embodiments.

[0053] Also shown in this embodiment, the base electrode 208 and the enclosing electrode 210 have an array of through apertures 230. More specifically, the through apertures 230 are evenly distributed on the base electrode 208 and the enclosing electrode 210. These through apertures 230 can help other surfacing material to bind to the body of concrete which is confined within the electrode assembly 200. The through apertures 230 can be unevenly distributed on the base electrode 208 and the enclosing electrode 210 in some other embodiments. The through apertures 230 can be used to electrically connect the first and second conductors 220 and 222 to the enclosing electrode 210 and the base electrode 208, respectively. As best seen in Fig. 2B, the first and second conductors 220 and 222 are attached via a nut and bolt 232 inserted through corresponding through apertures 230. Other binding methods can be used and may be preferred in industrial settings. Such binding methods can include, but are not limited to, crimping, soldering, welding, and the like.

[0054] As shown, the upper portion of the enclosing electrode 210 and the base electrode 208 shares a common shape, i.e., a rectangular shape. It is understood that other shapes including, but not limited to, square, parallelogram, ovoid, and the like can be used as well in some other embodiments. However, the size of the upper portion 210a and of the base electrode 208 differ. As discussed above, this difference in surface area allows the gap 216 to be formed between the distal edge 210c of the wall portion 210b of the enclosing electrode 210 and an outer edge 208a of the base electrode 208. This gap 216 provides electrical insulation between the enclosing electrode 210 and the base electrode 208.

[0055] It was found preferable to ensure that the first and second conductors 220 and 222, or any other conductors providing an electrical current to the electrode assembly, are electrically connected to the base electrode 208 and the enclosing electrode 210 on a bottom plane of the electrode assembly 202. As such, the first and second conductors 220 and 222 are farther away from the upper portion 210a of the enclosing electrode 210. As the electrode assembly 202 is shaped as a tile, the bottom positioning of the first and second conductors 220 and 222 can facilitate a side-by-side arrangement of such tile-like electrode assemblies 202. Additionally or alternately, the base electrode 208 and the enclosing electrode 210 are exposed towards the bottom of the electrode assembly. Such a configured can allow the electrode assembly to be energized by inserting it into a circuit where the hot wire is connectedis arranged in a way to make contact with the base electrode 208 and the neutral is arranged such that it contacts the enclosing electrode 210. Although electrical wires are shown in this embodiment, the electrical connection are not limited to electrical wires. For example, electrical contact can be achieved using a network of bus bars, spring contact or any other configuration that can allow a low resistance contact between the current source and the electrode assembly.

[0056] Fig. 3 shows an example in which the electrode assembly 302 has been coated with a layer 340 of protective material. Depending on the embodiment, the protective material can include a thermally insulating material, an electrically insulating material, a mechanically protective material, or any combination thereof. In this specific embodiment, the protective material is a polymer such as epoxy. It was found that by surrounding the electrode assembly with such a polymer layer, the integrity of the underlying electrode assembly can be preserved overtime and under harsh environmental conditions. Moreover, the polymer material being an electrical insulator can help prevent stray current from exiting the electrode assembly 302. The layer 340 of protective material can be optimized to improve the thermal efficiency of the electrode assembly 302 such that an optimal thermal conductivity can be achieved. The layer 340 of protective material can allow for a constant heat flux that can limit excessive radiation. In other words, the layer 340 can add a thermal damping to the thermal cycles of the electrode assembly 302. In this example, the layer 340 of protective material covers the whole exterior of the electrode assembly 302. In other words, the layer 340 covers the outer surfaces of the upper portion 310a and of the wall portion 310b as well as the outer surface of the base electrode 308. However, in some other embodiments, the layer 340 of protective material can be limited to a coating of the upper portion 310a of the enclosing electrode 310. In some further embodiments, the layer 340 of protective material can also cover the wall portion 310b of the enclosing electrode 310, thereby covering the exterior surfaces of the whole enclosing electrode 310.

[0057] Fig. 4 shows another example of an electrode assembly 402. As shown, the electrode assembly 402 is provided with different layers 440a and 440b for protecting purposes among others. For instance, the electrode assembly 402 has a first layer 440a that may contain high performance concrete covering the upper portion 410a and the wall portion 410b of theenclosing electrode 410. The high performance concrete can be provided in the form of conventional high performance concrete (HPC), or in the form of ultra-high-performance concrete (UHPC), depending on the embodiment. It is intended that the first layer 440a of high performance concrete provides both mechanical and electrical protection. The mechanical protection can help maintaining the integrity of the underlying electrode assembly, whereas the electrical insulation provided by the high-performance concrete can help further prevents stray currents to reaching the meltable precipitation that can accumulate on a top surface. Moreover, the electrode assembly 402 has a second layer 440b of polymer (e.g., polystyrene polymer) on which the base electrode 408 sits. The second layer 440b of polymer provides electrical insulation and thermal insulation. As such, providing the second layer 440b with enhanced thermal insulation properties can help direct heat above and across the electrode assembly 402 rather than losing that heat to the underground. In some other embodiments, such as the one shown in Fig. 4A, the second layer 440b’ not only has a base portion resting under the base electrode 408’, but also extends from a periphery of the base portion to a distal edge surrounding the wall portion of the enclosing electrode 410’, thereby further directing heat towards the upper portion of the enclosing electrode 410’.

[0058] Fig. 5 is a graph showing top surface and internal temperatures as a function of time for the electrode assembly of Fig. 4. As shown, the top surface temperature trails behind the internal temperature with a difference of about 5 degrees Celsius. In this embodiment, a top surface temperature surface above the melting point can be reached within 20 minutes or so. It is understood that these results only provide the behaviour of an exemplary system and can be modified by altering the concrete mix, the thickness of the volume of body of concrete contained within the electrode assembly, and the like. Fig. 6 is a graph showing top surface and internal temperatures as a function of power for the electrode assembly of Fig. 4. As shown, the average power that was required to raise the top surface temperature, and maintain it above the melting point, is about 1000 W / m2. Such an average power was found to be acceptable within the parameters of the experiment.

[0059] Referring now to Fig. 7, the controller of the system of Fig. 1 can be provided as a combination of hardware and software components. The hardware components can be implemented in the form of a computing device 700, an example of which is described withreference to Fig. 7. The computing device 700 can have a processor 702, a memory 704, and I / O interface 706. Instructions 708 for operating the electrode assembly can be stored on the memory 704 and accessible by the processor 702.

[0060] The processor 702 can be, for example, a general-purpose microprocessor or microcontroller, a digital signal processing (DSP) processor, an integrated circuit, a field- programmable gate array (FPGA), a reconfigurable processor, a programmable read-only memory (PROM), a programmable logic controller (PLC), or any combination thereof.

[0061] The memory 704 can include a suitable combination of any type of computer-readable memory that is located either internally or externally such as, for example, random-access memory (RAM), read-only memory (ROM), compact disc read-only memory (CDROM), electro-optical memory, magneto-optical memory, erasable programmable read-only memory (EPROM), and electrically-erasable programmable read-only memory (EEPROM), Ferroelectric RAM (FRAM) or the like.

[0062] Each I / O interface 706 enables the computing device 700 to interconnect with one or more input devices, such as a keyboard(s), mouse(s), sensor(s), external network(s) and accessible memory system(s), or with one or more output devices such as voltage source(s), electrical component(s), external network(s) and accessible memory system(s).

[0063] Each I / O interface 706 enables the controller to communicate with other components, to exchange data with other components, to access and connect to network resources, to server applications, and perform other computing applications by connecting to a network (or multiple networks) capable of carrying data including the Internet, Ethernet, plain old telephone service (POTS) line, public switch telephone network (PSTN), integrated services digital network (ISDN), digital subscriber line (DSL), coaxial cable, fibre optics, satellite, mobile, wireless (e.g., Wi-Fi, WiMAX), SS7 signaling network, fixed line, local area network, wide area network, and others, including any combination of these.

[0064] The computing device 700 and any software application that can be run by the computing device 700 are meant to be examples only. Other suitable embodiments of the controller can also be provided, as it will be apparent to the skilled reader.

[0065] Fig. 8 shows a method 800 for method for melting accumulation of meltable precipitation on a given surface. The method 800 is described with reference to the system 100 of Fig. 1 for ease of reading.

[0066] At step 802, an electrical current is applied across the electrode assembly. More specifically, the electrical current is applied between the base electrode and the enclosing electrode. In some embodiments, the electrical current is fed by a standard 120 or 240 V AC source. It is intended that the electrical current can be any type of electrical current, and is thereby not limited to the standard 120 or 240 V AC. For instance, by modifying the nature of the concrete mix, some other ranges of electrical current can be used. In these embodiments, the AC source has a phase line connected to the base electrode and a neutral line connected to the enclosing electrode. Of course, the phase lines can be reversed in some embodiments.

[0067] At step 804, electrical paths are formed within the electrode assembly. The electrical paths extend between the base electrode and an interior surface of the enclosing electrode, and across the body of concrete, which causes heating of the body of concrete via Joule effect. It is noted that the step 804 includes a step in which the enclosing electrode prevents stray currents from leaving the electrode assembly, or at least a volume thereof. In this way, stray currents risks are greatly reduced. As discussed above, the electrical voltage energizing these electrical paths are not limited to low voltages, and they can range between 120 V and 240 V, for instance.

[0068] At step 806, the heat generated within the body of concrete melts the meltable precipitation accumulating on the exposed surface, if any. The generated heat can migrate towards the outer edges of the electrode assembly and, when meltable precipitation are present, can melt the precipitations and prevent accumulation on the exposed surface of the electrode assembly. As discussed above, the surface exposed to the meltable precipitation is not necessarily the upper portion of the enclosing electrode, as one or more protective layers can be used. Indeed, such protective layers can improve adherence to the road surfaces, as metal would not generate a sufficient amount of friction with shoes and tires in at least some situations.

[0069] In some embodiments, a certain number of such electrode assemblies are used as tiles to pave an infrastructure. Accordingly, in some situations, a first group of electrode assemblies may be connected to a first voltage source whereas a second group of electrode assemblies may be connected to a different voltage source.

[0070] In some embodiments, a controller communicatively coupled to the voltage source, and to external precipitation detector, can receive a precipitation indicator from a precipitation detector. The controller can be configured to activate the voltage source based on the precipitation indicator. The precipitation indicator can be indicative of snow presence, ice presence, graupel presence, hail presence, temperature below the melting point, or a combination thereof.

[0071] In some embodiments, the electrode assembly is energized at all times to maintain the top surface temperature above a certain threshold. In these embodiments, the controller can be omitted. In some other embodiments, the electrode assembly is energized only when the top surface temperature falls below the certain threshold or when it is detected that some meltable precipitated have fallen or formed on the top surface.

[0072] In some embodiments, the method 800 is performed only when it is determined that the temperatures and the forecast weather warrants it. In some embodiments, for instance, a computer-implemented weather forecast module can detect that the surface temperature is approximately -10°C. At this temperature and up to 2°C (inclusively), possibilities of snow, freezing rain or other type of accumulation arise. The method 800 can be performed and kept in an energized state that can promote thawing of the precipitation. In some embodiments, a computing device communicatively coupled to an external network can forecast the probability of precipitations and alter the performance of the electrode assembly based on these forecast. That is, in the fall when cool mornings occur, encountering a precipitation event can be less probable. The same temperature in the month of February may, however, lead to meltable precipitations.

[0073] In certain embodiments, the electrode assembly includes a number of identical electrode assemblies adjacent one another. In these embodiments, the electrode assemblies can heat the given surface upon application of the electrical current. Moreover, the method800 can include a step of detecting that one of the identical electrode assemblies is defective, and a step of replacing the defective electrode assembly with a working electrode assembly while the other ones of the working electrode assemblies remain in position, and / or in operation.

[0074] In another aspect, there is provided a method of assembling an electrode assembly such as the one disclosed in this disclosure. At a first step, the enclosing electrode disposed on a resting surface, with the interior surface of the enclosing electrode facing upwards. At a second step, a first conductor is electrically connected to an exposed portion of the enclosing electrode and a second conductor is electrically connected to an exposed portion of the base electrode. At a third step, a fresh mixture of concrete is poured into the enclosing electrode. The freshly poured mixture fills the cavity formed by the interior surfaces of the enclosing electrode until it reaches the distal edge of the enclosing electrode and the sought volume of concrete is in place. Typically, the concrete includes concrete having one or more different type(s) of conductive inclusions. These conductive inclusions can be added to fresh concrete, and mixed therein, prior to pouring into the enclosing electrode and curing to produce the concrete. Examples of such conductive inclusions can include, but are not limited to, graphite powder, conductive aggregate, carbon fibre, steel fibre, copper powder, copper-coated steel fibers, graphene, carbon powder, steel powder, steel shavings, other carbonaceous materials and any other suitable conductive inclusions. At a fourth step, the base electrode is pressed against the freshly poured concrete in a manner which is spaced away from the distal edge of the enclosing electrode. Generally, the base electrode is deposited on the freshly poured concrete in a manner centered with the enclosing electrode. In some embodiments, a jig is used to satisfactorily position the base electrode on the freshly poured concrete. In these embodiments, the jig is deposited on the freshly poured concrete and stays there as the concrete cures. As such, the jig is preferably made of an electrically insulation material. In this way, when the fresh concrete cures, the concrete maintains the base electrode in position as it is adhered thereto. At a fifth step, the freshly poured concrete is cured for a given period of time. In optional step(s), when the fresh concrete has been satisfactorily cured, the electrode assembly can be coated with a protective layer such as disclosed above. In some embodiments, this second step of electrically connecting the first and second conductors tothe enclosing electrode and the base electrode, respectively, can be performed after the pouring of the fresh mixture of concrete.

[0075] The installation of the resulting electrode assembly in an infrastructure can differ from one embodiment to another. For instance, following the above-mentioned method of assembly, the electrode assembly can be flipped over so that the base electrode faces downwards and the top surface of the enclosing electrode faces upwards. Then, the base electrode can be deposited within an infrastructure in a manner which causes the top surface of the enclosing electrode to match a working plane of the infrastructure. In embodiments where the infrastructure is a road resting on ground, the base electrode can be buried in the ground, for instance. In embodiments where the infrastructure is a pavement resting on a concrete slab, the base electrode can be received on the concrete slab.

[0076] As can be understood, the examples described above and illustrated are intended to be exemplary only. For instance, although the enclosing electrode and the base electrode have been described as being made of metal sheet, the electrodes can be made of any electrically conductive material. In some embodiments, the electrodes can be made of electrically conductive concrete that would be slightly more conductive than the concrete within the electrode assembly, and less resistive, than the concrete of the body of the electrode assembly. The system described herein can be used in the context of any infrastructure including, but not limited to, road(s), sidewalk(s), patio(s), terrasse(s), airport runway(s), bus shelter(s), footbridge(s), pavement(s), and the like. Of course, the system described herein is not limited to outdoor applications, as it can also be used in indoor systems as an alternative to heat a space including, but not limited to, an interior parking space. The first conductor can be more specifically connected to the wall portion, and even more specifically closer to the distal edge than to the upper portion. It is understood that although the electrode assemblies illustrated in this disclosure are of rectangular shape, they can have an ovoid shape, a circular shape, a pentagonal shape, and the like. The scope is indicated by the appended claims.

Claims

WHAT IS CLAIMED IS:1 . A system for preventing accumulation of meltable precipitation on a given surface, the system comprising: an electrode assembly having: a base electrode; an enclosing electrode having an upper portion spaced away from the base electrode, and a wall portion extending from a periphery of the upper portion to a distal edge surrounding the base electrode; the enclosing electrode and base electrode defining a volume extending within the electrode assembly; a gap between the distal edge of the wall portion and the base electrode; and a body of concrete within the volume of the electrode assembly; and a voltage source having a first conductor electrically connected to the enclosing electrode and a second conductor electrically connected to the base electrode, the voltage source operable to circulate an electrical current from the base electrode to the enclosing electrode and across the body of concrete, to melt the meltable precipitation when the meltable precipitation is in thermal contact with the upper portion of the enclosing electrode.

2. The system of claim 1 wherein the voltage source is a high-voltage source, the electrical current having a voltage value ranging between 60 V and 1 000 V.

3. The system of claim 1 or 2 wherein the voltage source is an alternating current (AC) voltage source, the electrical current being an AC current.

4. The system of claim 3 wherein the first conductor is a neutral line and the second conductor is a phase line.

5. The system of any one of claims 1 to 4 wherein the electrode assembly has a layer of protective material on the electrode assembly.

6. The system of claim 5 wherein the protective material includes at least one of a thermally insulating material, an electrically insulating material, and a mechanically protective material.

7. The system of claim 5 or 6 wherein the protective layer includes at least one of an epoxy, a polystyrene polymer and a high-performance concrete.

8. The system of any one of claims 5 to 7 wherein the layer has a top surface portion deposited on the upper portion of the enclosing electrode.

9. The system of any one of claims 5 to 8 wherein the layer encloses the upper portion of the enclosing electrode, the wall portion of the enclosing electrode and the base electrode.

10. The system of any one of claims 1 to 9 wherein the layer has a base portion on which the base electrode sits.1 1. The system of claim 10 wherein the base portion of the layer extends from a periphery of the base portion to a distal edge surrounding the wall portion of the enclosing electrode.

12. The system of any one of claims 1 to 1 1 wherein the periphery of the enclosing electrode has a parallelogram shape.

13. The system of any one of claims 1 to 12 wherein the base electrode is parallel to the upper portion of the enclosing electrode.

14. The system of any one of claims 1 to 13 wherein the base electrode and the enclosing electrode have a plurality of through apertures.

15. The system of claim 14 wherein the plurality of through apertures are evenly distributed on the base electrode and the enclosing electrode.

16. The system of any one of claims 1 to 15 wherein the base electrode and the enclosing electrode are made of electrically conductive concrete, the electrically conductive concrete having a lower electrical resistance than an electrical resistance of the concrete of the body.

17. The system of claim 1 further comprising a controller having a processor and a nonvolatile memory having stored thereon instructions which when executed by the processor operate the voltage source.

18. The system of claim 17 further comprising a precipitation detector communicatively coupled to the controller, the controller receiving a precipitation indicator from the precipitation detector and activating the voltage source based on the precipitation indicator.

19. The system of claim 1 wherein the base electrode has a first surface area, and the upper portion of the enclosing electrode has a second surface area greater than the first surface area of the base electrode.

20. The system of claim 1 wherein the concrete of the body has a resistivity value ranging between about 500 and 100,000 Q cm, and most preferably between about 2,000 and 80,000 Q cm.

21. The system of claim 1 wherein the concrete of the body incorporates a plurality of electrically conductive particles distributed in the concrete of the body.

22. A method for melting accumulation of meltable precipitation on a given surface, the method comprising: applying an electrical current across an electrode assembly, the electrode assembly having a base electrode resting within an infrastructure, an enclosing electrode having an upper portion exposed to meltable precipitation, and a wall portion extending from a periphery of the upper portion to a distal edge surrounding the base electrode and forming a gaptherearound, and a body of concrete within a volume extending between the base electrode and the enclosing electrode; said electrical current forming electrical paths extending between the base electrode and an interior surface of the enclosing electrode, and across the body of concrete, thereby heating the body of concrete; and said heating including melting said meltable precipitation accumulating on the given surface.

23. The method of claim 22 wherein said electrical current is an alternating current, the base electrode receiving a phase line of the alternating current, and the enclosing electrode receiving a neutral line of the AC.

24. The method of claim 22 wherein the electrode assembly includes a plurality of identical electrode assemblies adjacent one another, the plurality of identical electrode assemblies heating the given surface upon said applying.

25. The method of claim 24 further comprising detecting that one of the plurality of identical electrode assemblies is defective; and replacing the one of the plurality of identical electrode assemblies with a working electrode assembly while the other ones of the plurality of identical electrode assemblies remain in position.

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