Concrete pavement, precast body, manufacturing methods thereof, and non-contact power feeding road

Abstract

To provide a concrete pavement which has high relative permittivity and low dielectric loss tangent and can obtain high power supply efficiency when used for non-contact power supply, a precast body, a manufacturing method of these, and a non-contact power supply track.SOLUTION: A concrete pavement 120 used for facilities that supply power in a non-contact manner to charging targets on road surfaces, includes: aggregates; a cement-hardened body that binds the aggregates; and polymer that exists in gaps between the aggregates and the cement-hardened body. The dielectric loss tangent is less than 0.1. The polymer has higher relative permittivity and lower dielectric loss tangent than the aggregates. Therefore, when the polymer is contained in the concrete pavement 120 as described above, the relative permittivity increases and the dielectric loss tangent decreases. As a result, when power is supplied in a non-contact manner through the concrete pavement 120, high power supply efficiency can be obtained.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a concrete pavement, a precast body, a manufacturing method thereof, and a non-contact power supply road surface used for a facility that supplies power to a charging target on a road surface in a non-contact manner.

Background Art

[0002] One of the methods of wireless power supply, the electric field coupling method, is a method of transmitting power by installing electrodes on the power supply side and the power receiving side, respectively, and using the electric field generated when the electrodes are close to each other. When power is supplied to a charging target such as an electric vehicle in a non-contact manner through a road surface by the electric field coupling method, the electrode on the power supply side is embedded inside the pavement of the road surface. Regarding such a non-contact power supply facility through a road surface, a structure for improving power supply efficiency has been studied.

[0003] For example, in Patent Document 1, a member made of a material in which a substance having a relative permittivity or a dielectric loss tangent or both lower than those of general aggregates is mixed into an asphalt material or a cement-based material has been proposed. Further, in Patent Document 2, cement asphalt emulsion mortar, dense-graded asphalt mixture, and polymer-containing cement concrete have been proposed as paving materials.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In order to obtain high power supply efficiency by the electric field coupling method, it is important to maximize the action of electrostatic induction in the electric field generated when an alternating voltage is applied. Therefore, it is preferable that the relative permittivity of the paving body is high. Also, in order to reduce the energy loss of the transmitted power, it is preferable that the dielectric tangent of the paving body is low.

[0006] For the member described in Patent Document 1, a paving body in which a substance having a lower relative permittivity than general aggregate is mixed is used, and the relative permittivity of the paving body becomes low. Also, in Patent Document 2, although a concrete paving material made of cement asphalt emulsion mortar, dense graded asphalt mixture or polymer-containing cement has been proposed, its basis and detailed description have not been described.

[0007] The present invention has been made in view of such circumstances, and provides a concrete paving, a precast body, a manufacturing method thereof, and a non-contact power supply traveling path that have a high relative permittivity and a low dielectric tangent and can obtain high power supply efficiency when used for non-contact power supply.

Means for Solving the Problems

[0008] (1) To achieve the above object, the concrete paving of the present invention is a concrete paving used for a facility that supplies power to a charging target on a road surface in a non-contact manner, and includes aggregate, a cement hardened body that binds the aggregates together, and a polymer present in the gaps between the aggregate and the cement hardened body, and is characterized in that the dielectric tangent is less than 0.1.

[0009] The polymer has a higher relative permittivity and a lower dielectric loss tangent than the aggregate. Therefore, when the polymer is included in the concrete pavement as described above, its relative permittivity increases and the dielectric loss tangent decreases. As a result, when non-contact power supply is performed through this concrete pavement, high power supply efficiency can be obtained. In addition, the polymer has water repellency, and when used on the road surface, it can prevent the intrusion of moisture into its interior. As a result, it is possible to suppress the energy loss during power supply due to moisture intrusion, and to prevent insulation failure between the power supply side electrodes and leakage current onto the road surface.

[0010] (2) Further, the concrete pavement of the present invention is characterized in that the mass ratio P / C of the unit blending amount P of the polymer to the unit cement amount C of the concrete is 5% or more and 25% or less.

[0011] Since P / C is 5% or more in this way, the dielectric loss tangent can be reduced, the relative permittivity can be increased, and the waterproof performance can be enhanced. On the other hand, since P / C is 25% or less, it can support with sufficient strength even when vehicles pass frequently.

[0012] (3) Further, the concrete pavement of the present invention is characterized in that the polymer is a styrene-butadiene copolymer. Thereby, the corrosion resistance to the electrode is improved.

[0013] (4) The concrete pavement of the present invention is a concrete pavement used for a facility that supplies power to a charging target on the road surface in a non-contact manner, and includes an aggregate, a cement hardened body that binds the aggregates together, and a rapid hardening admixture present in the gap between the aggregate and the cement hardened body, and is characterized in that the dielectric loss tangent is less than 0.1.

[0014] The rapid hardening admixture has a higher relative permittivity and a lower dielectric loss tangent than the aggregate. Therefore, when the rapid hardening admixture is included in the concrete pavement as described above, its relative permittivity increases and the dielectric loss tangent decreases. As a result, when non-contact power supply is performed through this concrete pavement, high power supply efficiency can be obtained.

[0015] (5) Further, the concrete pavement of the present invention is characterized in that the mass ratio F / B of the unit blending amount F of the rapid hardening admixture to the total amount B of the unit cement amount of the concrete and the unit blending amount of the rapid hardening admixture is 10% or more and 50% or less.

[0016] Since F / B is 10% or more in this way, the dielectric loss tangent can be reduced and the relative permittivity can be increased. As a result, high power supply efficiency can be obtained. On the other hand, since F / B is 50% or less, it can support with sufficient strength even when vehicles pass frequently.

[0017] (6) Further, the concrete pavement of the present invention is characterized in that the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole. Since the dielectric loss tangent of air is 0, the dielectric loss tangent decreases by including 2.0 vol% or more of air in the concrete pavement. As a result, energy loss can be reduced and high power supply efficiency can be obtained. At the stage of fresh concrete, the air content of 4.0 vol% or more is more preferable. On the other hand, since the relative permittivity of air is 1, by including 8.0 vol% or less of air in the concrete, the relative permittivity of the concrete pavement can be maintained high and high strength can be maintained.

[0018] (7) Further, the concrete pavement of the present invention is characterized in that, as the aggregate, it contains an aggregate having a dielectric loss tangent of less than 0.1. Thereby, the energy loss due to the concrete pavement can be reduced and high power supply efficiency can be obtained.

[0019] (8) Further, the concrete pavement of the present invention is characterized in that, as the aggregate, it contains an aggregate having a relative permittivity of 2.0 or more. Thereby, high power supply efficiency can be obtained.

[0020] (9) Further, the concrete pavement of the present invention is characterized in that the aggregate is a ceramic body of an oxide containing any one or more elements of Al, Mg, and Si, and contains a sintering aid having a melting point lower than that of the oxide.

[0021] When the aggregate contains alkali metals such as Na and K as impurities, the dielectric loss tangent increases. By containing a sintering aid, alkali metal ions are trapped in the pores in the crystal structure during the firing process of the aggregate, and the dielectric loss tangent can be reduced by suppressing ion migration in the crystal.

[0022] (10) Further, the non-contact power supply road surface of the present invention is characterized in that the road surface is formed by the concrete pavement described in the above (1) to (9). Vehicles such as self-driving automobiles, monorail tracks, and forklifts in factories pass through the same location with their wheels many times. If a non-contact power supply road surface is constructed with the concrete pavement material as described above, it has better wear resistance than asphalt and can be used for a long time.

[0023] (11) Further, the precast body of the present invention is a precast body used for a facility that supplies power to a charging target on the road surface in a non-contact manner, and includes an aggregate, a cement hardened body that binds the aggregates together, and a polymer existing in the gaps between the aggregate and the cement hardened body, and is characterized in that the dielectric loss tangent is less than 0.1. Thereby, concrete pavement can be prefabricated in a factory and assembled on site, reducing the on-site work load.

[0024] (12) Further, the precast body of the present invention is a precast body used for a facility that supplies power to a charging target on the road surface in a non-contact manner, and includes an aggregate, a cement hardened body that binds the aggregates together, and a rapid hardening admixture existing in the gaps between the aggregate and the cement hardened body, and is characterized in that the dielectric loss tangent is less than 0.1. Thereby, concrete pavement can be prefabricated in a factory and assembled on site, reducing the on-site work load.

[0025] (13) Further, the non-contact power supply road surface of the present invention is characterized in that the road surface is formed by the precast body described in the above (11) or (12). Thereby, the on-site work load can be reduced, it has excellent wear resistance, and long-term use is possible.

[0026] (14) Further, the method for manufacturing a concrete pavement according to the present invention is a method for manufacturing a concrete pavement used for a facility that supplies power to a power supply target on a road surface in a non-contact manner, and aggregates, cement, water, and a polymer are used. A step of measuring and kneading so that the mass ratio P / C of the unit polymer blending amount P to the unit cement amount C is 5% or more and 25% or less to generate concrete, and a step of forming a road surface using the generated concrete are included. As a result, the dielectric loss tangent of the concrete pavement can be reduced, the relative permittivity can be increased, the waterproof performance can be improved, and sufficient strength can be provided to support even when vehicles frequently pass.

[0027] (15) Further, the method for manufacturing a concrete pavement according to the present invention is a method for manufacturing a concrete pavement used for a facility that supplies power to a power supply target on a road surface in a non-contact manner, and aggregates, cement, water, and a quick-setting admixture are used. A step of measuring and kneading so that the mass ratio F / B of the unit blending amount F of the quick-setting admixture to the total amount B of the unit cement amount and the unit blending amount of the quick-setting admixture is 10% or more and 50% or less to generate concrete, and a step of forming a road surface using the generated concrete are included. As a result, the dielectric loss tangent of the concrete pavement can be reduced and the relative permittivity can be increased. As a result, high power supply efficiency can be obtained, and sufficient strength can be provided to support even when vehicles frequently pass.

[0028] (16) Further, the method for manufacturing a precast body according to the present invention is a method for manufacturing a precast body used for a facility that supplies power to a power supply target on a road surface in a non-contact manner, and aggregates, cement, water, and a polymer are used. A step of measuring and kneading so that the mass ratio P / C of the unit polymer blending amount P to the unit cement amount C is 5% or more and 25% or less to generate concrete, and after forming a mold, pouring the generated concrete into the mold and performing steam curing to generate a precast body are included. As a result, a precast body with high power supply efficiency, waterproof performance, and strength can be prepared, and the work efficiency at the paving site can be improved.

[0029] (17) Further, the method for manufacturing a precast body of the present invention is a method for manufacturing a precast body used in a facility that supplies power to a charging target on a road surface in a non-contact manner. The method includes measuring aggregate, cement, water, and a rapid hardening admixture so that the mass ratio F / B of the unit blending amount F of the rapid hardening admixture to the total amount B of the unit cement amount and the unit blending amount of the rapid hardening admixture is 10% or more and 50% or less, and kneading to produce concrete; and after forming a mold, placing the produced concrete in the mold to produce a precast body. Thus, a precast body with high power supply efficiency and strength can be prepared, and the work efficiency at the paving site can be improved.

Effects of the Invention

[0030] According to the present invention, when a concrete pavement or a precast body has a high relative permittivity and a low dielectric loss tangent and is used for non-contact power supply, high power supply efficiency can be obtained.

Brief Description of the Drawings

[0031]

Figure 1

Embodiments for Carrying Out the Invention

[0032] Embodiments of the present invention will be described below. The described embodiments are a preferred example, and the present invention is not limited thereto.

[0033] [Power Supply Facility] FIGS. 1(a) and (b) are a schematic diagram showing a power supply facility and a diagram showing its equivalent circuit, respectively. As shown in FIG. 1(a), the power supply facility 100 includes a power supply device 110 and a concrete pavement 120.

[0034] The power supply device 110 is buried in the soil 800 below the concrete pavement 120 and includes a high-frequency power supply 111 and a power supply side electrode 112. The high-frequency power supply 111 applies an alternating voltage to the power supply side electrode 112 at a predetermined frequency, for example, 13.56 MHz. The power supply side electrode 112 is provided on the back side of the concrete pavement 120, and causes electrostatic induction to the charging target by applying an alternating voltage through the concrete pavement 120. In this way, non-contact (wireless) power supply to the charging target becomes possible.

[0035] Examples of the charging target include, for example, an electric vehicle configured to be chargeable. As the type of vehicle, it is particularly effective for passenger cars, but is not limited thereto, and may be a forklift, a construction vehicle, or a monorail vehicle. Further, it may be a device that requires charging, not limited to vehicles.

[0036] In the example shown in FIG. 1(a), an electric vehicle 900 is schematically shown as the charging target. The electric vehicle 900 includes a front wheel tire 910, a wheel 920, a shaft 930, an in-vehicle circuit 940, and a motor 950. During charging, the electric vehicle 900 is driven and stopped so that the front wheel tire 910 is disposed directly above the power supply side electrode 112. Then, the wheel 920 functions as a power receiving side electrode with respect to the voltage application on the power supply side, current flows through the shaft 930, and the in-vehicle circuit 940 is charged. Then, the motor 950 is driven by the newly charged power.

[0037] As shown in FIG. 1(b), when the example of the non-contact power supply system shown in FIG. 1(a) is represented by an equivalent circuit, it becomes an RLC series circuit using the concrete pavement 120 as a dielectric. As can be seen from this equivalent circuit, whether the energy of the high-frequency power supply 111 can be given to the in-vehicle circuit 940 with high efficiency depends on the constituent material of the concrete pavement 120.

[0038] The concrete pavement 120 is composed of a concrete pavement material described later and forms the road surface of the non-contact power supply road. As a result, the concrete pavement 120 has a high relative permittivity and a low dielectric loss tangent, and when used for non-contact power supply, high power supply efficiency can be obtained. The non-contact power supply road is used, for example, as a road for automobiles, a parking lot, a track such as a monorail, or a floor in a factory where a moving body travels. Automatically driven automobiles, monorail vehicles, forklifts in factories, etc. have multiple vehicles using the power supply facility 100 over a long period of time, so the wheels pass through the same location many times. The concrete pavement material is more wear-resistant than asphalt and can be used for a long time when used for a non-contact power supply road.

[0039] Note that when moisture penetrates into the road surface, the dielectric loss tangent of the concrete pavement material increases and the energy loss becomes large. Also, it becomes difficult to ensure insulation between the electrodes on the power supply side and between people or other devices on the road surface. Therefore, it is preferable to prevent moisture from penetrating into the road surface.

[0040] [Configuration of Concrete Pavement] The concrete pavement 120 includes, as a concrete pavement material, aggregate, a cement hardened body, and at least one of a polymer and a quick-setting admixture. The aggregate is not limited to general aggregate (an aggregate of mineral particles) composed of gravel or sand, and may be an aggregate of ceramic particles. The cement hardened body is obtained by hardening cement through a hydration reaction and binds the aggregates together. The polymer refers to a compound formed by polymerization of a plurality of monomers into a chain or network shape and exists in the gaps between the aggregate and the cement hardened body.

[0041] As described above, by including a polymer or a rapid hardening admixture having a higher relative permittivity and a lower dielectric loss tangent than the aggregate, the relative permittivity of the entire concrete pavement 120 increases and the dielectric loss tangent decreases. As a result, when non-contact power supply is performed through the concrete pavement 120, high power supply efficiency can be achieved. Further, it is preferable that both the polymer and the rapid hardening admixture are included, and in that case, higher power supply efficiency can be obtained. Further, the polymer has water repellency, and due to the effect of the polymer filling the voids inside the concrete, the formation of a continuous air layer is suppressed, and when used for the road surface, moisture intrusion into the road surface can be prevented. As a result, it is possible to suppress energy loss during power supply due to moisture intrusion and to prevent insulation failure between the power supply side electrodes and leakage current onto the road surface. Note that if the polymer is contained to such an extent that it can be detected by infrared spectroscopic analysis (FT-IR), the effect of preventing moisture intrusion can be obtained.

[0042] Examples of the polymer used include styrene-butadiene copolymer (latex), polyacrylate copolymer, ethylene-vinyl acetate copolymer, vinyl acetate copolymer, polychloropropylene, and the like. Among these, styrene-butadiene copolymer (latex) is most preferable from the viewpoint of corrosion resistance to the electrodes.

[0043] The latex has water repellency (waterproofness) and can prevent moisture intrusion into the road surface. When moisture intrudes into the concrete pavement 120, the dielectric loss tangent increases and the energy loss increases when an alternating voltage is applied. By using the latex, it is possible to suppress the energy loss associated with the increase in the dielectric loss tangent due to moisture intrusion and to prevent insulation failure between the power supply side electrodes 112 and leakage current onto the road surface.

[0044] The content of the polymer is preferably controlled such that the mass ratio P / C of the unit compounding amount of the polymer (polymer addition amount) P to the unit cement amount (cement addition amount) C at the fresh concrete stage is 5% or more and 25% or less. Since P / C is 5% or more, the dielectric loss tangent can be reduced, the relative permittivity can be increased, and the waterproof performance can be enhanced. On the other hand, since P / C is 25% or less, it can support with sufficient strength even when vehicles frequently pass. The lower limit of P / C is more preferably 10% or more, and the upper limit is more preferably 20% or less. Note that the mass ratio of the polymer addition amount P is preferably set such that the total value of the amount of the polymer-containing admixture and the amount of water is constant. Thereby, a decrease in strength due to an increase in the polymer addition amount can be suppressed.

[0045] The above range is at the fresh concrete stage, during the production of concrete. When converted to the volume ratio of the polymer in the cement hardened body in the concrete pavement 120, it corresponds to approximately 15% or more and 50% or less. In the industry, it is common to manage and express the ratios of various materials (such as water, cement, aggregate, water reducing agent, and other chemicals) in the concrete mixture by weight at the fresh concrete stage. Such notation is often used because the final composition of the concrete greatly depends on the external environment, the time-dependent change in the hydration reaction of the cement, the water absorption rate of the aggregate, etc., and it is difficult to specify.

[0046] Examples of the quick-setting admixture include those mainly composed of one or more selected from the group of quick-setting substances such as calcium aluminates, sodium aluminate, alums containing calcined alum, activated alumina, aluminum hydroxide, aluminum sulfate, calcium nitrite, calcium nitrate, etc. Particularly preferred quick-setting admixtures are those mainly composed of calcium aluminates. The quick-setting admixture is preferably in powder form.

[0047] The content of the quick-setting admixture is preferably controlled such that the mass ratio F / B of the unit dosage F of the quick-setting admixture to the total amount B of the unit cement amount C and the unit dosage (quick-setting admixture addition amount) F of the quick-setting admixture at the fresh concrete stage is 10% or more and 50% or less. Since F / B is 10% or more, the dielectric loss tangent can be reduced, the relative permittivity can be increased, and the power supply efficiency can be enhanced. On the other hand, since F / B is 50% or less, sufficient strength can be provided even when vehicles frequently pass. The lower limit of F / B is more preferably 15% or more, and the upper limit is more preferably 35% or less.

[0048] Similar to the content of the polymer, the above range is at the fresh concrete stage, during the production of concrete. When converted to the volume ratio of the quick-setting admixture in the cement hardened body in the concrete pavement 120, it corresponds to approximately 1.3% or more and 10% or less.

[0049] The air content in the fresh concrete preferably occupies a range of 2.0 vol% or more and 8.0 vol% or less of the total. Since the dielectric loss tangent of air is 0, by including 2.0 vol% or more of air in the concrete, the dielectric loss tangent decreases. As a result, energy loss can be reduced, and high power supply efficiency can be obtained. On the other hand, the relative permittivity of air is 1, and by including 8.0 vol% or less of air in the concrete, the relative permittivity of the concrete pavement 120 can be maintained high, and high strength can be maintained. The lower limit of the air content is more preferably 4.0 vol% or more, and the upper limit is more preferably 6.0% or less. The air content in the fresh concrete can be adjusted by using a chemical admixture for concrete called an AE agent or an AE water-reducing agent and can be measured by a fresh concrete air content measuring instrument.

[0050] The dielectric tangent of at least a part of the aggregate is preferably less than 0.1. In this case, the aggregate has a lower dielectric tangent than that of a general natural material aggregate. This can reduce the energy loss through the concrete pavement 120 and obtain high power supply efficiency. Also, the relative permittivity of at least a part of the aggregate is preferably 2.0 or more. In this case, the aggregate has a higher relative permittivity than that of a general aggregate. This can obtain high power supply efficiency. Note that it is more preferable that the average dielectric tangent or relative permittivity of the aggregate as a whole is within a predetermined range. Further, it is more preferable that the dielectric tangent or relative permittivity of all the aggregates is within a predetermined range.

[0051] The addition amount of the aggregate with a dielectric tangent less than 0.1 may be appropriately adjusted so that the dielectric tangent of the concrete pavement is less than 0.1. For example, among the aggregates, fine aggregate can be natural crushed sand, and coarse aggregate with a dielectric tangent less than 0.1 can be used. The proportion of the aggregate with a dielectric tangent less than 0.1 preferably accounts for 50% or more of the total aggregate.

[0052] The aggregate may be a ceramic body of an oxide containing any one or more elements of Al, Mg, and Si, and may contain a sintering aid having a melting point lower than that of the oxide. In this case, when the aggregate contains an alkali metal such as Na or K as an impurity, the dielectric tangent increases. However, by containing a sintering aid, alkali metal ions are trapped in the pores in the crystal structure during the firing process of the aggregate, and the dielectric tangent can be reduced by suppressing ion movement in the crystal.

[0053] Such constituent materials of the aggregate include, for example, alumina (Al 2 O 3 ), magnesia (MgO), silica (SiO 2 ), mullite (3Al 2 O 3 ·2SiO 2 ), forsterite (2MgO·SiO 2 ), steatite (MgO·SiO 2 ), spinel (MgO·Al 2 O 3) and cordierite (2MgO·2Al 2 O 3 ·5SiO 2 ) etc. are mentioned.

[0054] Regarding the sintering aid, alumina will be taken as an example for explanation. As the sintering aid for alumina, when the total amount of SiO 2 and MgO is 0.2 wt% or more and 1.0 wt% or less, and the weight ratio (SiO 2 / MgO) is 2 or more and 4 or less is added, during the sintering process, a cordierite phase with a lower melting point than alumina precipitates at the grain boundaries. In the process of forming this cordierite, alkali metal ions are captured by the pores in the crystal structure, and by suppressing the ion movement in the crystal, the dielectric loss tangent can be reduced.

[0055] [Manufacturing method of concrete pavement] The manufacturing method of the concrete pavement 120 configured as described above will be explained. First, a predetermined amount of aggregate, cement, water, and polymer are weighed and kneaded with a mixer (specific examples of each formulation etc. will be described later). At this time, it is preferable that the mass ratio P / C of the polymer addition amount P to the cement addition amount C is 5% or more and 25% or less, and the mass ratio F / B of the rapid hardening admixture addition amount F to the total amount B of the cement addition amount C and the rapid hardening admixture addition amount F is 10% or more and 50% or less. At this time, it is more preferable that P / C is 10% or more and 20% or less, and F / B is 15% or more and 35% or less. The concrete obtained in this way is placed, compacted, and the surface is finished, whereby the concrete pavement 120 is manufactured.

[0056] The concrete with a dielectric loss tangent of less than 0.1 manufactured in this way is used between the power supply side electrode that supplies power non - contact and the vehicle etc. that is powered. The dielectric loss tangent of the concrete pavement only needs to be less than 0.1 during use, but it is preferably less than 0.1 before 28 days after manufacturing, and more preferably less than 0.1 before 7 days after manufacturing.

[0057] Note that the concrete pavement 120 is preferably manufactured by placing the mixed raw materials on site. This allows the concrete pavement 120 to be formed flexibly according to the site conditions.

[0058] The concrete pavement 120 may be pre-formed as precast concrete (precast body) in a factory in advance and laid for the non-contact power supply travel path. The precast body and the power supply side electrode parts may be integrated and transported in the factory in advance and then constructed on site. This enables the concrete pavement to be pre-fabricated in the factory and assembled on site, reducing the on-site working time.

[0059] When making precast concrete, it is preferable to include a step of steam curing the concrete manufactured in the same manner as the above concrete pavement after placing it in a mold or after placing it in a mold and demolding it. By performing steam curing, a denser hardened body is formed to prevent the intrusion of moisture inside, and at the same time, the dielectric tangent can be surely reduced because the compounded water surely forms hydrates and decreases. Note that steam curing may be performed by a known method. For example, it may be performed at a temperature of 50 to 80°C for 2 to 12 hours. Also, when the material contains a rapid hardening admixture, the step of steam curing may be omitted.

[0060] [Experiment] An experiment was conducted on the concrete pavement as described above. Test specimens of 500×500×50 mm simulating a road surface were fabricated using various concrete pavement materials. The age of the specimens was 28 days. Table 1 is a table showing an example of the materials used in the experiment and their formulations. Based on the example shown in Table 1, the aggregates and polymers were replaced with other types respectively. As shown in Table 2, the addition amount of the polymer was made constant by keeping the total value of the amount of the polymer-containing admixture L and the amount of water W (the symbols are the same as in Table 1).

[0061]

Table 1

[0062]

Table 2

[0063] Six types of aggregates were used, namely general aggregate, steatite, alumina, mullite, forsterite, and special aggregate. The general aggregate is gravel mainly composed of silica (SiO 2 ), and containing Al 2 O 3 and MgO as secondary components. The special aggregate was prepared by adding 0.4 wt% of SiO 2 and 0.2 wt% of MgO as sintering aids to alumina and heat-treating at 1600 °C. The dielectric properties of the aggregates were measured using an impedance analyzer. Table 3 is a table showing the relative permittivity and dielectric tangent of the aggregates used in the experiment.

[0064]

Table 3

[0065] Styrene-butadiene copolymer (SBR), polyacrylate copolymer (PAE), and ethylene-vinyl acetate copolymer (EVA) were used as polymers. The polymers were added to the cement at a weight ratio of 5 - 25%. This corresponds to a volume ratio of 14 - 45%.

[0066] Facet (registered trademark, manufactured by Pacific Materials Co., Ltd.) was used as the rapid hardening admixture. The rapid hardening admixture was added at a weight ratio of 15 - 35% based on the total weight of the cement and the rapid hardening admixture. This corresponds to a volume ratio of 16 - 37%. Also, the air content in the fresh concrete was measured using a fresh concrete air content measuring instrument in accordance with JIS A 1115 and adjusted to be 2.0 - 8.0 vol%.

[0067] As comparative examples, test specimens were also prepared for general concrete and general asphalt without containing polymers. The dielectric properties of each test specimen were measured using an impedance analyzer. Table 4 is a table showing the manufacturing conditions and measurement results of the test specimens.

[0068]

Table 4

[0069] From the obtained results, power supply efficiency simulations were performed using electromagnetic field analysis software. Also, two copper electrodes with dimensions of 250×200×1 mm were attached at 50 mm intervals to the center of the back surface of the test piece, and water was sprayed onto the surface of the test piece while applying an alternating voltage to the electrodes. The resistance value between the electrodes at that time was measured with a tester to confirm the presence or absence of insulation failure. The insulation test results were represented as 〇 when the resistance was 10 MΩ or more, △ when it was less than 10 MΩ but 1 MΩ or more, and × when it was less than 1 MΩ. In addition, the compressive strength of various test pieces was measured. Table 5 shows the simulation results and test results.

[0070]

Table 5

[0071] In all the examples, the power supply efficiency was 80% or more. Also, no insulation failure was observed. The compressive strength of the examples was 35 MPa or more, satisfying the values required for concrete paving. Note that for concrete paving, a flexural strength of 4.5 MPa or more and a compressive strength of 35 MPa or more are required.

[0072] When comparing Example 3 and Example 12 where the polymer addition amount and the air content in the mixture were almost equal, the dielectric tangent of Example 12 with the addition of a rapid hardening admixture was lower than that of Example 3, and a higher power supply efficiency was obtained. Also, regarding the compressive strength, Example 12 was higher. According to such a comparison, by further adding not only a polymer but also a rapid hardening admixture, the dielectric tangent can be further reduced. And when non-contact power supply is performed through concrete paving with further addition of a rapid hardening admixture, a high power supply efficiency can be obtained.

[0073] The compressive strength of Example 5 with a P / C of 25% was 38 MPa, and the compressive strength of Example 13 with an air content of 8.0 vol% was 36 MPa. This compressive strength is close to the lower limit of the standard required for concrete pavement. Therefore, it is not preferable for the air content of concrete pavement to exceed 8.0 vol% or the P / C at the fresh concrete stage to exceed 25%. As shown in the table, in the comparative example, the power supply efficiency was very low, and it was found that insulation failure occurred.

Explanation of Signs

[0074] 100 Power supply facility 110 Power supply device 111 High-frequency power supply 112 Power supply side electrode 120 Concrete pavement 800 Soil 900 Electric vehicle 910 Front wheel tire 920 Wheel 930 Shaft 940 On-vehicle circuit 950 Motor

Claims

1. A concrete pavement used for a facility that supplies power to a charging target on a road surface in a non-contact manner, aggregate, a cement hardened body that binds the aggregates together, and a polymer present in the gaps between the aggregates and the cement hardened body, and comprising: the polymer is any one of a styrene-butadiene copolymer, a polyacrylate copolymer, or an ethylene-vinyl acetate copolymer, the mass ratio P / C of the unit blending amount P of the polymer to the unit cement amount C of the concrete is 5% or more and 25% or less, the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole, as the aggregate, an aggregate having a dielectric loss tangent of less than 0.1 and a relative dielectric constant of 2.0 or more is contained, a concrete pavement characterized in that the dielectric loss tangent is less than 0.

1.

2. A concrete pavement used for a facility that supplies power to a charging target on a road surface in a non-contact manner, aggregate, a cement hardened body that binds the aggregates together, and a rapid hardening admixture present in the gaps between the aggregates and the cement hardened body, and comprising: the rapid hardening admixture is a substance mainly composed of calcium aluminates, the mass ratio F / B of the unit blending amount F of the rapid hardening admixture to the total amount B of the unit cement amount of the concrete and the unit blending amount of the rapid hardening admixture is 10% or more and 50% or less, the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole, as the aggregate, an aggregate having a dielectric loss tangent of less than 0.1 and a relative dielectric constant of 2.0 or more is contained, a concrete pavement characterized in that the dielectric loss tangent is less than 0.

1.

3. The concrete pavement according to claim 1 or claim 2, wherein the aggregate is a ceramic body of an oxide containing one or more elements of Al, Mg, and Si, and contains a sintering aid having a melting point lower than that of the oxide.

4. A non-contact power supply road surface characterized in that a road surface is formed by the concrete pavement according to any one of claims 1 to 3.

5. A precast body used for a facility that supplies power to a charging target on a road surface in a non-contact manner, aggregate, a cement hardened body that binds the aggregates together, and a polymer present in the gaps between the aggregates and the cement hardened body, and comprising: The polymer is any one of a styrene-butadiene copolymer, a polyacrylate copolymer, or an ethylene-vinyl acetate copolymer, the mass ratio P / C of the unit compounding amount P of the polymer to the unit cement amount C of the concrete is 5% or more and 25% or less, the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole, as the aggregate, it contains an aggregate having a dissipation factor of less than 0.1 and a relative permittivity of 2.0 or more, a precast body characterized in that the dissipation factor is less than 0.

1.

6. A precast body used for a facility that supplies power to a charging target on a road surface in a non-contact manner, aggregates, a cement hardened body that binds the aggregates together, a rapid-hardening admixture present in the gaps between the aggregates and the cement hardened body, and the rapid-hardening admixture is a substance mainly composed of calcium aluminates, the mass ratio F / B of the unit compounding amount F of the rapid-hardening admixture to the total amount B of the unit cement amount of the concrete and the unit compounding amount of the rapid-hardening admixture is 10% or more and 50% or less, the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole, as the aggregate, it contains an aggregate having a dissipation factor of less than 0.1 and a relative permittivity of 2.0 or more, a precast body characterized in that the dissipation factor is less than 0.

1.

7. A non-contact power supply road surface characterized in that the road surface is formed by the precast body according to Claim 5 or Claim 6.

8. A method for manufacturing a concrete pavement used for a facility that supplies power to a charging target on a road surface in a non-contact manner, a step of measuring and kneading aggregates, cement, water, and a polymer so that the mass ratio P / C of the unit polymer compounding amount P to the unit cement amount C of the concrete is 5% or more and 25% or less to produce concrete, a step of forming a road surface using the produced concrete, and the polymer is any one of a styrene-butadiene copolymer, a polyacrylate copolymer, or an ethylene-vinyl acetate copolymer, the mass ratio P / C of the unit compounding amount P of the polymer to the unit cement amount C of the concrete is 5% or more and 25% or less, the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole, A method for manufacturing a concrete pavement, characterized by containing an aggregate having a dielectric loss tangent of less than 0.1 and a relative dielectric constant of 2.0 or more as the aggregate.

9. A method for manufacturing a concrete pavement used for a facility that supplies power to a charging target on a road surface in a non-contact manner, a step of measuring and kneading aggregate, cement, water, and a rapid-hardening admixture so that the mass ratio F / B of the unit blending amount F of the rapid-hardening admixture to the total amount B of the unit cement amount and the unit blending amount of the rapid-hardening admixture is 10% or more and 50% or less to produce concrete; a step of forming a road surface using the produced concrete, and includes the rapid-hardening admixture is a substance mainly composed of calcium aluminates, the mass ratio F / B of the unit blending amount F of the rapid-hardening admixture to the total amount B of the unit cement amount and the unit blending amount of the rapid-hardening admixture of the concrete is 10% or more and 50% or less, the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole, A method for manufacturing a concrete pavement, characterized by containing an aggregate having a dielectric loss tangent of less than 0.1 and a relative dielectric constant of 2.0 or more as the aggregate.

10. A method for manufacturing a precast body used for a facility that supplies power to a charging target on a road surface in a non-contact manner, a step of measuring and kneading aggregate, cement, water, and a polymer so that the mass ratio P / C of the unit polymer blending amount P to the unit cement amount C is 5% or more and 25% or less to produce concrete; a step of forming a mold, then placing the produced concrete in the mold, and steam-curing to produce a precast body, and includes the polymer is any one of a styrene-butadiene copolymer, a polyacrylate copolymer, or an ethylene-vinyl acetate copolymer, the mass ratio P / C of the unit blending amount P of the polymer to the unit cement amount C of the concrete is 5% or more and 25% or less, the air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole, A method for manufacturing a precast body, characterized by containing an aggregate having a dielectric loss tangent of less than 0.1 and a relative dielectric constant of 2.0 or more as the aggregate.

11. A method for manufacturing a precast body used for a facility that supplies power to a charging target on a road surface in a non-contact manner, A step of measuring aggregate, cement, water, and a rapid-hardening admixture so that the mass ratio F / B of the unit blending amount F of the rapid-hardening admixture to the total amount B of the unit cement amount and the unit blending amount of the rapid-hardening admixture is 10% or more and 50% or less, and kneading to produce concrete; A step of forming a mold and then placing the produced concrete in the mold to produce a precast body; The rapid-hardening admixture is a substance mainly composed of calcium aluminates; The mass ratio F / B of the unit blending amount F of the rapid-hardening admixture to the total amount B of the unit cement amount and the unit blending amount of the rapid-hardening admixture of the concrete is 10% or more and 50% or less; The air content of the concrete occupies a region of 2.0 vol% or more and 8.0 vol% or less of the whole; The method for producing a precast body is characterized in that, as the aggregate, it contains an aggregate having a dielectric loss tangent of less than 0.1 and a relative dielectric constant of 2.0 or more.

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