JP2000120269A - Concrete heating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concrete heating method wherewith heating can be made efficiently with a simple device. SOLUTION: Electromagnetic wave is applied to concrete 12 with an electromagnetic wave irradiation device 14. Carbon fibers 28 mixed in the concrete 12 absorb electromagnetic wave irradiated from a horn antenna. Then, the carbon fibers 28 which absorbed electromagnetic wave become heated, and the concrete 12 is heated by means of heat exchange. Therefore, the concrete 12 can be heated by simple means of carbon fibers 28 and electromagnetic wave irradiation device. Since heating can be made directly not only at the surface of the concrete 12 but also at the inside of the concrete 12, efficient heating becomes possible for the concrete 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for heating concrete for heating and curing concrete.

[0002]

2. Description of the Related Art In general, concrete develops strength by the progress of hydration reaction of cement and water. Thus, heating the concrete and raising the temperature promotes the hydration reaction and reduces the time required to obtain concrete of the same strength.

For example, in the production of a precast concrete panel, the concrete after casting is cured by heating, so that the time of removal from the mold is accelerated to improve the efficiency of panel production.

[0004] In winter and cold regions, the low temperature causes the hydration reaction to be hindered, delaying the development of concrete strength, and causing the concrete structure to be damaged by repeated freezing or freezing and thawing of water in the concrete. In some cases, concrete may be cured by heating to prevent it.

On the other hand, since the hydration reaction of cement and water is an exothermic reaction, when concrete having a large cross section (for example, mass concrete) is applied, a temperature difference occurs between the center of the concrete and the surface of the concrete (concrete). The temperature in the center is higher.) Due to this temperature difference, a stress is generated inside the concrete (a compressive stress is generated at the center of the concrete and a tensile stress is generated at the surface of the concrete because the thermal expansion is larger at the center of the concrete). In addition, damage such as cracks occurs in concrete. In order to prevent this, the concrete surface may be heated or kept warm for a certain period.

Here, as a method of heating concrete, a shed or enclosure is provided around a structure containing concrete, and the inside thereof is heated using a boiler, a jet heater, a stove, or the like, and the heat inside the structure is heated. Method for heating concrete (hereinafter referred to as "space heating method")
In addition, a method of directly heating the concrete surface by attaching a heating sheet or a hotbed wire to the surface of the concrete, or irradiating infrared light to the concrete with an infrared lamp or the like (hereinafter referred to as “surface heating method”) is there.

[0007]

However, the above space heating method requires excessive facilities such as a shed and an enclosure.

In addition, since the inside of the shed or the enclosure is heated and the concrete inside is heated by the heat inside the shed or the enclosure, the heat inside the shed or the enclosure wastes much heat, and therefore, energy is more than that of directly heating the concrete. Efficiency is reduced.

Further, since kerosene or light oil is used as a fuel, there is a risk of fire or the like. Further, when a boiler or a jet heater is used, there is a problem that noise is loud.

On the other hand, in the above-described surface heating method, when a heating sheet or a hotbed wire is used, the heating sheet or the hotbed wire is easily damaged by an external impact or the like.

When the heating sheet or the hotbed wire uses electricity as an energy source, the wiring from the power source is broken, or concrete cracks or breaks, and a part of the heating sheet or the hotbed wire becomes damaged. If it is damaged and an electric circuit such as a heating sheet or a hotbed wire is cut, the entire circuit becomes unusable.
Moreover, concrete itself contains a large amount of water, and since the site or factory where the concrete is constructed is in a humid environment, there is a high risk of electric shock and electric leakage.

Further, if a part of the heat generating sheet or the hotbed wire becomes damaged and the whole becomes unusable, a concrete molding plate is cut on site, and the shape and dimensions according to various sections in which concrete is used. Can not be processed.

When using an infrared lamp or the like,
If there is a shield that blocks infrared rays between the infrared lamp or the like and concrete, the heating effect is hindered.

In particular, when using the boiler, jet heater, stove or the like of the above-mentioned space heating method, or when using the infrared lamp or the like of the above-mentioned surface heating method, it is possible to cover the concrete surface with a heat insulating member. Energy efficiency is reduced due to heat leakage from the concrete surface.

Further, in the above-mentioned space heating method and surface heating method,
Since the heat given to the concrete surface is mainly transmitted to the inside by heat conduction, the temperature of the whole concrete rises,
The entire concrete does not have a uniform temperature distribution. Also,
It takes a certain amount of time for the heat applied to the concrete surface to be transmitted to the inside mainly by heat conduction. Therefore, depending on the amount of heat applied, it takes time until the entire concrete reaches a required temperature.

In addition, when heating and curing concrete, it is necessary to prevent peripheral equipment and human bodies from being affected.

The present invention has been made in view of the above circumstances, and has as its object to provide a concrete heating method capable of efficiently heating with simple equipment.

[0018]

According to the first aspect of the present invention, an electromagnetic wave absorbing and heating material that absorbs electromagnetic waves and generates heat is mixed into concrete, and electromagnetic waves are radiated from outside the concrete by electromagnetic wave radiating means that radiates electromagnetic waves. Then, the irradiated electromagnetic wave is absorbed by the electromagnetic wave absorbing and heating material to generate heat, the concrete is heated and cured by the heat generated by the electromagnetic wave absorbing and heating material, and, at that time, an electromagnetic wave shielding member for shielding the electromagnetic wave. It is characterized in that it is installed to prevent leakage of electromagnetic waves to a portion other than the portion to be heated and cured.

According to the first aspect of the present invention, the electromagnetic wave radiated from the electromagnetic wave irradiating means is absorbed by the electromagnetic wave absorbing and heating material mixed in the concrete and generates heat. Thereby, the concrete is heated and cured by the heat exchange action.

Therefore, the concrete can be heated basically with simple equipment including only the electromagnetic wave absorbing and heating material and the electromagnetic wave irradiation means. Further, not only the surface of the concrete but also the inside of the concrete can be directly heated, so that the concrete can be efficiently heated.

Further, in this case, since the electromagnetic wave shielding member prevents the electromagnetic wave from leaking to a portion other than the portion to be heated and cured, it is possible to prevent the electromagnetic wave from affecting nearby equipment and the human body.

According to a second aspect of the present invention, concrete is coated with an electromagnetic wave absorbing and heating member that absorbs electromagnetic waves and generates heat.
An electromagnetic wave is radiated from the outside of the concrete by electromagnetic wave irradiating means for irradiating the electromagnetic wave, the irradiated electromagnetic wave is absorbed by the electromagnetic wave absorbing and heating member to generate heat, and the concrete is heated and cured by the heat generated by the electromagnetic wave absorbing and heating member. At this time, an electromagnetic wave shielding member for shielding the electromagnetic waves is provided to prevent leakage of the electromagnetic waves to a portion other than the portion to be heated and cured.

According to the second aspect of the present invention, the electromagnetic wave radiated from the electromagnetic wave radiating means is absorbed by the electromagnetic wave absorbing and heating member coated on the concrete, and generates heat. Thereby, the concrete is heated and cured by the heat exchange action.

Therefore, concrete can be basically heated with simple equipment including only the electromagnetic wave absorbing and heating member and the electromagnetic wave irradiation means.

Further, in this case, since the electromagnetic wave shielding member prevents the electromagnetic wave from leaking to a portion other than the portion to be heated and cured, it is possible to prevent the electromagnetic wave from affecting nearby equipment and the human body.

According to a third aspect of the present invention, in the method for heating concrete according to the first or second aspect, the electromagnetic wave shielding member is installed on an outer periphery of a building constructed using the concrete. It is characterized by preventing electromagnetic waves from leaking out of the building.

According to the third aspect of the present invention, the electromagnetic wave shielding member is installed on the outer periphery of the building constructed using the concrete to be cured by heating, thereby preventing the leakage of the electromagnetic wave to the outside of the building. Electromagnetic waves can be prevented from affecting equipment and the human body existing outside the building.

According to a fourth aspect of the present invention, in the method for heating concrete according to any one of the first to third aspects, the electromagnetic wave shielding member is formed by using an electromagnetic wave absorbing material, and the electromagnetic wave shielding member is provided with an electromagnetic wave absorbing member. It is characterized by absorbing.

According to the fourth aspect of the present invention, since the electromagnetic wave shielding member is constituted by using the electromagnetic wave absorbing material and absorbs the electromagnetic wave, the electromagnetic wave reflected by the electromagnetic wave shielding member leaks to a portion other than the heating and curing portion, or the building is constructed. Leakage to the outside of the object can be prevented, so that the electromagnetic wave shielding member can efficiently shield electromagnetic waves.

According to a fifth aspect of the present invention, in the method for heating concrete according to any one of the first to fourth aspects, the heating for inhibiting the transmission of electromagnetic waves between the concrete and the electromagnetic wave irradiation means is performed. A control member is provided, and the intensity of the electromagnetic wave transmitted through the heating control member is controlled by the heating control member.

According to the fifth aspect of the present invention, a heating control member is provided between the concrete and the electromagnetic wave irradiating means for inhibiting transmission of the electromagnetic wave, and the intensity of the electromagnetic wave transmitted through the heating control member is controlled by the heating control member. Therefore, the degree of temperature rise of the concrete on the back side of the heating control member can be controlled.

According to a sixth aspect of the present invention, in the method for heating concrete according to any one of the first to fifth aspects, a heat insulating member is provided on the surface of the concrete or inside the concrete. The heat insulating member shields heat generated by the electromagnetic wave absorbing and heating member or the electromagnetic wave absorbing and heating member.

According to the sixth aspect of the invention, the heat generated by the electromagnetic wave absorbing and heating member or the electromagnetic wave absorbing and heating member is shielded by the heat insulating member. Therefore, for example, when the heat insulating member is disposed on the surface of concrete, the heat generated by the electromagnetic wave absorbing and heating material or the electromagnetic wave absorbing and heating member is prevented from leaking to the outside of the concrete. Can be.

On the other hand, for example, when this heat insulating member is disposed inside concrete, the electromagnetic wave absorbing and heating material or the heat generated by the electromagnetic wave absorbing and heating member is prevented from leaking from the disposed portion. Can be increased.

According to a seventh aspect of the present invention, in the method for heating concrete according to any one of the first to sixth aspects, a reflecting member for reflecting electromagnetic waves on the surface of the concrete or inside the concrete is provided. The electromagnetic wave radiated from the electromagnetic wave irradiating means by the reflection member is reflected in the direction of the electromagnetic wave absorbing and heating material or the electromagnetic wave absorbing and heating member and is absorbed again.

According to the seventh aspect of the present invention, the electromagnetic wave radiated from the electromagnetic wave irradiating means is irradiated by the electromagnetic wave radiating means or the electromagnetic wave absorbing heat generating member by the reflecting member arranged on the surface of the concrete or inside the concrete. Since the light is reflected in the direction and is absorbed again, the electromagnetic wave absorbing and heating member or the electromagnetic wave absorbing and heating member increases the electromagnetic wave absorption efficiency, and therefore, the energy efficiency can be increased.

According to an eighth aspect of the present invention, in the method for heating concrete according to any one of the first to sixth aspects, the electromagnetic wave absorbing and heating material is applied to the concrete for each part of the concrete. It is characterized in that the mixing amount or the covering amount of the electromagnetic wave absorbing and heating member on the surface of the concrete is adjusted.

According to the eighth aspect of the present invention, the amount of the electromagnetic wave absorbing and heating material mixed into the concrete or the amount of the electromagnetic wave absorbing and heating member coated on the concrete surface is adjusted for each part of the concrete. The amount of heat generated by the electromagnetic wave absorbing and heating material or the electromagnetic wave absorbing and heating member can be adjusted for each part, and therefore, the amount of heating can be adjusted for each part of the concrete.

[0039]

FIG. 1 is a sectional view of a building 50 according to an embodiment of the present invention.

As shown in FIG. 1, the building 50 is a three-story building having 12 concrete floors and walls. The building 50 is under construction, and a temporary scaffold 5 is provided around the periphery of the building 50.
2 are provided. On each floor of the building 50, the electromagnetic wave irradiation device 14 as an electromagnetic wave irradiation unit is arranged.

Although not shown, by arranging the electromagnetic wave irradiation device 14 on the temporary scaffold 52, the concrete 12 can be irradiated with electromagnetic waves also from the outside of the building 50.

FIG. 2 shows a schematic configuration diagram of the electromagnetic wave irradiation device 14.

As shown in FIG. 2, the electromagnetic wave irradiation device 14 is provided with a horn antenna 20 for irradiating the concrete 12 with an electromagnetic wave.
It has. Here, the horn antenna 20 has a conical shape, and the bottom surface of the cone is
It has become. The horn antenna 20 is connected to the support 4
6 and a joint 48 to which a ball joint or the like is applied, and the horn antenna 20 is swung around the joint 48 so that the direction of irradiation of the electromagnetic wave can be freely changed. Further, the horn antenna 20 can move freely by moving the support column 46.

Thus, the entire surface 26 of the concrete 12 can be irradiated with electromagnetic waves from the horn antenna 20.

The horn antenna 20 is connected to an electromagnetic wave oscillating device (not shown) for oscillating electromagnetic waves by a coaxial cable 24, and the electromagnetic wave oscillating device is connected to a power supply (not shown) for supplying power. Here, the electromagnetic wave oscillation device is configured by a magnetron or the like that generates an electromagnetic wave.

FIG. 3 shows a sectional view of the concrete 12.

As shown in FIG. 3, a reinforcing bar 38 such as a reinforcing bar is inserted in the concrete 12 in parallel with the surface 26 of the concrete 12. Carbon fiber 28 as an absorption heating material is mixed.

Here, the carbon fiber 28 is mixed with the material such as sand or gravel at the time of kneading the concrete 12 or is mixed in the concrete 12 by being previously installed at a place where the concrete 12 is to be constructed.

The surface 26 of the concrete 12 is covered with a heat insulating member 32 for shielding the heat generated by the carbon fiber 28, and the inside of the concrete 12 is parallel to the surface 26 of the concrete 12 and has reinforcing bars 38. , A plurality of heat insulating members 32 (two in the present embodiment) are provided.

Here, the heat insulating member 32 is made of a non-conductive material that does not hinder the electromagnetic wave transmission, or is made of a non-conductive material that does not hinder the electromagnetic wave transmission. The heat insulating member 32 covering the surface 26 of the concrete 12 is also used as a formwork of the concrete 12.

Further, the reinforcing bar 38 is connected to the horn antenna 2.
It is also used as a reflecting member that reflects electromagnetic waves emitted from zero.

As shown in FIG.
6, a conductive mesh 5 as a heating control member
4 is attached. The conductive mesh 54 is mainly made of a conductive material.

Here, the conductive mesh 54 is formed by adjusting the size of the opening of the mesh in accordance with the wavelength of the electromagnetic wave emitted from the horn antenna 20 or the like. Accordingly, the intensity of the electromagnetic wave transmitted through the conductive mesh 54 can be controlled, whereby the irradiation intensity of the electromagnetic wave applied to the concrete 12 on the back side to which the conductive mesh 54 is attached is controlled. Therefore, the conductive mesh 5
The intensity of electromagnetic waves absorbed by the carbon fibers 28 mixed in the concrete 12 on the back side to which the concrete 4 is attached is controlled, and the amount of heating of the concrete 12 can be controlled.

As shown in FIG. 1, on the third floor of the building 50 and near the horn antenna 20, a conductive board 56 as an electromagnetic wave shielding member is provided. The horn antenna 2 is arranged so as to divide the floor into two spaces (hereinafter, of the two spaces on the third floor of the building 50 divided by the conductive board 56,
The side where 0 is present is referred to as “electromagnetic wave irradiator 58”, and the side where horn antenna 20 is not present is “electromagnetic wave non-irradiator 60”
). In addition, the conductive board 56 shields the electromagnetic wave emitted from the horn antenna 20, and
To prevent the electromagnetic wave from leaking to the electromagnetic wave non-irradiation section 60 from the outside. Thereby, it is possible to prevent the electromagnetic wave from affecting devices and the human body existing in the electromagnetic wave non-irradiation unit 60.

Here, at least one of a magnetic material such as ferrite and a conductive material such as carbon fiber is added to the conductive board 56 as an electromagnetic wave absorbing material, and these materials absorb electromagnetic waves. In addition, the electromagnetic wave can be prevented from being reflected, and thereby the electromagnetic wave shielding efficiency of the conductive board 56 can be increased.

Further, a conductive sheet 57 as an electromagnetic wave shielding member is attached to the temporary scaffold 52 installed on the outer periphery of the building 50. The conductive sheet 57 is attached so as to surround the building 50, shields the electromagnetic waves emitted from the horn antenna 20, and prevents the electromagnetic waves from leaking out of the building 50. Thereby, it is possible to prevent the electromagnetic waves from affecting devices and the human body existing outside the building 50.

The conductive sheet 57 does not contain a magnetic material such as ferrite or a conductive material such as carbon fiber as an electromagnetic wave absorbing material.
Shields electromagnetic waves by reflecting them. As described above, since the conductive sheet 57 does not contain a magnetic material such as ferrite or a conductive material such as carbon fiber, the cost can be reduced.

The conductive sheet 57 is not attached to the outer periphery of the building 50 on the side of the electromagnetic wave non-irradiation section 60 on the third floor. This is because the conductive sheet 57 is disposed inside the building 50 on the third floor. Since the board 56 shields electromagnetic waves, the building 50
This is because there is no need to attach the conductive sheet 57 to the outer periphery of the third floor on the side of the electromagnetic wave non-irradiation section 60.

Hereinafter, a heating operation of the concrete 12 according to the embodiment of the present invention will be described.

Electromagnetic waves are oscillated from an electromagnetic wave oscillation power supply (not shown) in response to power supplied from a power supply (not shown), and the entire surface 26 of the concrete 12 is irradiated with the electromagnetic waves from the horn antenna 20 through the coaxial cable 24. Here, the electromagnetic waves are emitted from inside and outside of the building 50.

The electromagnetic waves emitted from the horn antenna 20 to the concrete 12 are mixed in a portion (hereinafter, referred to as “the surface portion 40 of the concrete 12”) between the surface 26 of the concrete 12 and the heat insulating member 32. Absorbed by carbon fiber 28. In addition, the light is irradiated from the horn antenna 20 and the surface 40
Is reflected by the reinforcing bars 38 and absorbed by the carbon fibers 28 mixed in the surface portion 40 of the concrete 12.

On the other hand, the light is emitted from the horn antenna 20,
The electromagnetic waves that have passed through the surface portion 40 of the concrete 12 and are not reflected by the reinforcing bars 38
Since carbon fiber 2 does not impair the electromagnetic wave permeability, carbon fiber that passes through the heat insulating member 32 and is mixed into the concrete 12 at a portion other than the surface portion 40 of the concrete 12 (hereinafter, referred to as “the central portion 42 of the concrete 12”) Absorbed by 28.

Then, the carbon fibers 28 that have absorbed the electromagnetic waves generate heat, and the concrete 1
2 is heat cured.

As described above, the hydration reaction of cement and water is promoted, and the time required for obtaining concrete having the same strength is reduced.

Here, the carbon fibers 28 mixed into the surface portion 40 of the concrete 12 not only include the electromagnetic waves directly irradiated from the horn antenna 20 but also the reinforcing bars 38.
As a result, the electromagnetic wave reflected by the carbon fiber 28 is also absorbed, so that the efficiency of absorbing the electromagnetic wave of the carbon fiber 28 can be increased, and the calorific value of the carbon fiber 28 can be increased.

Further, the heat generated by the carbon fibers 28 mixed into the surface portion 40 of the concrete 12 does not leak to the center portion 42 of the concrete 12 by the heat insulating member 32.

On the other hand, the electromagnetic wave reaching the center 42 of the concrete 12 has passed through the surface 40 of the concrete 12 and
A part of the electromagnetic wave that has passed through is reflected on the surface portion 40 of the concrete 12 by the reinforcing bars 38, so that the carbon fiber 2 mixed in the central portion 42 of the concrete 12
The intensity of the electromagnetic wave absorbed by the carbon fiber 8 is smaller than the intensity of the electromagnetic wave absorbed by the carbon fiber 28 mixed in the surface portion 40 of the concrete 12.

As a result, the heating amount of the surface portion 40 of the concrete 12 can be larger than that of the center portion 42 of the concrete 12.

Therefore, when the outside temperature of the concrete 12 is low in winter or in a cold region, the hydration reaction of the cement and water near the surface of the concrete 12 is hindered, and the development of the strength of the concrete 12 is delayed. The structure near the surface of the concrete 12 can be prevented from being damaged due to repeated freezing or freezing and thawing of the water near the surface.

Further, when the concrete 12 is a mass concrete having a large cross section, since the hydration reaction of cement and water is an exothermic reaction, the temperature between the center of the concrete 12 and the vicinity of the surface of the concrete 12 is increased. Although a difference occurs, this temperature difference can be reduced by increasing the amount of heating near the surface of the concrete 12. For this reason, the difference in the expansion rate of the concrete 12 between the center of the concrete 12 and the vicinity of the surface of the concrete 12 can be reduced, so that the stress generated inside the concrete 12 is reduced, and Can be prevented from being damaged.

The heat generated by the carbon fibers 28 mixed in the concrete 12 is prevented from leaking to the outside of the concrete 12 by the heat insulating member 32 coated on the surface 26 of the concrete 12. For this reason, energy efficiency can be improved.

Further, the conductive mesh 54 attached to a part of the surface 26 of the concrete 12 is the electromagnetic wave radiated from the horn antenna 20 and the conductive mesh 5
4 is controlled. Accordingly, the intensity of electromagnetic waves absorbed by the carbon fibers 28 mixed in the concrete 12 on the back side to which the conductive mesh 54 is attached is controlled, and the amount of heating of the concrete 12 can be controlled.

Further, a conductive board 56 provided on the third floor of the building 50 and near the horn antenna 20 prevents leakage of electromagnetic waves from the electromagnetic wave irradiation section 58 to the electromagnetic wave non-irradiation section 60. Thereby, it is possible to prevent the electromagnetic wave from affecting devices and the human body existing in the electromagnetic wave non-irradiation unit 60.

Here, a magnetic material such as ferrite or a conductive material such as carbon fiber added to the conductive board 56 absorbs electromagnetic waves. Therefore, the conductive board 5
6 can be prevented from reflecting electromagnetic waves, and thereby the electromagnetic wave shielding efficiency of the conductive board 56 can be increased. Further, even if a device or a human body is present in the electromagnetic wave irradiation unit 58, the conductive board 56 does not reflect the electromagnetic wave, so that the electromagnetic wave reflected by the conductive board 56 affects the device or the human body present in the electromagnetic wave irradiation unit 58. Can be prevented.

Further, the conductive sheet 57 attached to the temporary scaffold 52 installed on the outer periphery of the building 50 shields the electromagnetic waves emitted from the horn antenna 20 and
Electromagnetic waves are prevented from leaking to the outside. Thereby, it is possible to prevent the electromagnetic waves from affecting devices and the human body existing outside the building 50.

In the present embodiment, basically, only the carbon fiber 28 and the electromagnetic wave irradiator 14 are used, and it is not necessary to connect the carbon fiber 28 and the electromagnetic wave irradiator 14 with a cable. Excessive facilities such as sheds and enclosures are not required like the law,
The concrete 12 can be heated with simple equipment.

Since the carbon fibers 28 are mixed into the concrete 12 at a uniform density, the entire concrete 12 can be heated so as to have a uniform temperature distribution.

Further, in the conventional space heating method or surface heating method, the heat given to the concrete surface is mainly transmitted to the inside of the concrete by heat conduction, and the temperature of the whole concrete rises. In this embodiment, the carbon fiber 28 mixed in the concrete 12 absorbs electromagnetic waves to generate heat, and the concrete 12 is heated by a heat exchange action. There is no need for the time for the heat of the surface of the concrete 12 to be transmitted to the inside of the concrete 12, so that the time required for the entire concrete 12 to reach the required temperature can be shortened, and the concrete 12 can be efficiently heated.

While the conventional space heating method heats the inside of a shed or enclosure and heats the concrete 12 by the heat inside, the present embodiment employs a carbon fiber 2
Since the heat generated by 8 directly heats the concrete 12,
Unnecessary energy is not consumed, and energy efficiency can be increased.

Further, since kerosene or light oil is not used as fuel, there is no danger of ignition or the like, and no noise is generated unlike a jet heater or a boiler.

In the case of using a heating sheet or a hot-bed wire of the conventional surface heating method, concrete is easily damaged when subjected to an external impact, and a part of the heating sheet or the hot-bed wire is damaged. In this embodiment, the carbon fiber 28 is not damaged, whereas the carbon fiber 28 is not damaged. Therefore, even if the concrete 12 receives an external impact, the carbon fiber 28 cannot be used. .

Further, since the carbon fiber 28 is not damaged, a molded plate using the carbon fiber 28 can be cut on site and processed into various shapes and sizes according to various cross sections.

Further, since it is not necessary to supply power to the carbon fiber 28, a cable connecting the carbon fiber 28 and the electromagnetic wave irradiation device 14 is not required, and no electric shock or electric leakage occurs.

In the case where a conventional surface heating infrared lamp or the like is used, a heating effect is hindered if there is a shield between the concrete and the infrared lamp, whereas in the present embodiment, the concrete 12 and the horn are used. Even if there is a shield between the antennas 20, it does not hinder the heating of the concrete 12 unless the shield blocks electromagnetic waves.

In this embodiment, the reinforcing bars 38 are used as the reflecting members.
In many cases, the dimension of the interval 8 (X in FIG. 4) is 150 mm or more. For example, when the electromagnetic wave irradiated from the horn antenna 20 is an electromagnetic wave in the GHz band, the reinforcing bar 38 is not sufficiently used as a reflecting member. The electromagnetic wave cannot be reflected, and the center part 42 of the concrete 12 and the surface part 40 of the concrete 12
The difference in the amount of heating does not occur sufficiently.

Therefore, a metal mesh having an opening parallel to the surface 26 of the concrete 12 and having a size suitable for the wavelength of the electromagnetic wave radiated from the horn antenna 20 near the heat insulating member 32 provided inside the concrete 12. By arranging the conductive fiber mesh together with the reinforcing bars 38, the electromagnetic wave passing through the surface portion 40 of the concrete 12 is sufficiently reflected, and the central portion 4
2 and a sufficient heating amount difference between the surface portion 40 of the concrete 12.

The dimensions of the opening of the metal mesh or the conductive fiber mesh are determined by the horn antenna 20
Of the wavelength of the electromagnetic wave radiated from the surface, the intensity of the electromagnetic wave reflected on the surface portion 40 of the concrete 12 and the concrete 12
Is determined by the ratio of the intensities of the electromagnetic waves transmitted through the central portion 42 of the concrete 12 and the central portion 42 of the concrete 12 and the concrete 12.
The difference in the amount of heating between the surface portions 40 is sufficiently generated.

Further, unlike the present embodiment, when the reinforcing bar 38 is not inserted into the concrete 12, the vicinity of the heat insulating member 32 provided parallel to the surface 26 of the concrete 12 and inside the concrete 12 is provided. Alternatively, only the above-described metal mesh or conductive fiber mesh may be provided.

In this embodiment, the concrete 1
Conductive mesh 54 as a heating control member on the surface 26 of
But with concrete 12 and horn antenna 2
The conductive mesh 54 may be provided between 0.

Further, in the present embodiment, the conductive mesh 54 is used as the heating control member. However, instead of using the conductive mesh 54, a conductive sheet mainly made of a conductive material may be used. .

In the present embodiment, the conductive board 56 and the conductive sheet 57 are used as the electromagnetic wave shielding member. However, instead of the conductive board 56 or the conductive sheet 57, the electromagnetic wave emitted from the horn antenna 20 is used. A conductive mesh 62 as shown in FIG. 5A having an opening having a size of 1/20 or less of the wavelength of FIG.

Here, the reason why the conductive mesh 62 is limited to the one having an opening whose size is 1/20 or less of the wavelength of the electromagnetic wave irradiated from the horn antenna 20 is that the opening of the opening is determined by the electromagnetic wave analysis simulation of the finite element method. Since it has been confirmed that the electromagnetic wave leaks out when the size exceeds 1/20 of the wavelength of the electromagnetic wave, the size of the opening of the conductive mesh 62 is 1/20 or less of the wavelength of the electromagnetic wave emitted from the horn antenna 20. This is because electromagnetic waves do not leak from the conductive mesh.

Here, at least one of a magnetic material such as ferrite and a conductive material such as carbon fiber may be added to the conductive mesh 62, so that these materials absorb electromagnetic waves. Electromagnetic wave reflection can be prevented, and the shielding efficiency of the conductive mesh 62 for electromagnetic waves can be increased.

Further, as an electromagnetic wave shielding member, FIG.
A combination of the conductive mesh 62 and the resin sheet 64 as described above may be used.

In this embodiment, the concrete 1
Although the carbon fibers 28 were mixed into the concrete 2 so that the density became uniform, the carbon fibers 28 may be mixed only near the surface of the concrete 12.

Thus, when the horn antenna 20 irradiates the concrete 12 with an electromagnetic wave, the carbon fibers 28 mixed near the surface of the concrete 12 absorb the electromagnetic wave and generate heat. Only can be heated.

In the present embodiment, the electromagnetic wave is emitted from inside and outside the building 50. However, when the electromagnetic wave can be emitted only from either the inside or the outside of the building 50, the electromagnetic wave May be coated with a reflector as a reflection member on the surface opposite to the surface to be irradiated.
Here, the reflection plate is made of a metal or a conductive material.

As a result, the reflection plate reflects the electromagnetic wave transmitted through the concrete 12 again in the direction of the carbon fiber 28, so that the electromagnetic wave absorbing efficiency of the carbon fiber 28 can be increased.
2 can increase the heating efficiency. (Modification) In this embodiment, as shown in FIG. 3, the carbon fiber 28 is mixed in the concrete 12, but when the carbon fiber 28 cannot be mixed in the concrete 12, as shown in FIG. The surface 26 of the concrete 12 may be covered with an electromagnetic wave absorbing and heating panel 44 as a heating member.

Here, the electromagnetic wave absorbing and heating panel 44 is made of carbon fiber and a heat-resistant material.

According to this modification, the heat generated by the electromagnetic wave absorbing and heating panel 44 absorbing the electromagnetic wave is prevented from leaking to the central portion 42 of the concrete 12 by the heat insulating member 32. Only the part 40 can be heated.

In this modification, the electromagnetic wave absorbing and heating panel 44 is used as the electromagnetic wave absorbing and heating member. However, instead of the electromagnetic wave absorbing and heating panel 44, carbon fiber and a heat-resistant material thinner than the electromagnetic wave absorbing and heating panel 44 are used. You may use the electromagnetic wave absorption heating sheet comprised.

In the present embodiment (including the modifications), the carbon fiber 28 is used as the electromagnetic wave absorbing and heating material, and the electromagnetic wave absorbing and heating panel 44 or the heat absorbing material made of carbon fiber and the heat resistant material is used as the electromagnetic wave absorbing and heating member. Although an electromagnetic wave absorbing and heating sheet was used, instead of the above carbon fiber, a magnetic material such as ferrite,
Conductive materials such as metal fibers and fibers having a surface coated with a conductive material may be used. Further, in place of the above carbon fiber, a combination of a magnetic material such as ferrite, or a conductive material such as carbon fiber, metal fiber, or a fiber coated with a conductive material on the surface may be used.

[0103]

According to the first aspect of the present invention, the electromagnetic wave radiated from the electromagnetic wave irradiating means is absorbed by the electromagnetic wave absorbing and heating material mixed in the concrete and generates heat. Thereby, the concrete is heated and cured by the heat exchange action.

Therefore, it is possible to heat concrete with simple equipment basically including only the electromagnetic wave absorbing heat generating material and the electromagnetic wave irradiation means. Further, not only the surface of the concrete but also the inside of the concrete can be directly heated, so that the concrete can be efficiently heated.

Further, in this case, since the electromagnetic wave shielding member prevents the electromagnetic wave from leaking to a portion other than the portion where heating and curing is performed, it is possible to prevent the electromagnetic wave from affecting nearby devices and the human body.

According to the second aspect of the present invention, the electromagnetic wave radiated from the electromagnetic wave radiating means is absorbed by the electromagnetic wave absorbing and heating member coated on the concrete to generate heat. Thereby, the concrete is heated and cured by the heat exchange action.

Therefore, the concrete can be basically heated with simple equipment including only the electromagnetic wave absorbing and heating member and the electromagnetic wave irradiation means.

Further, in this case, since the electromagnetic wave shielding member prevents the electromagnetic wave from leaking to a portion other than the portion to be heated and cured, it is possible to prevent the electromagnetic wave from affecting nearby devices and the human body.

According to the third aspect of the present invention, the electromagnetic wave shielding member is installed on the outer periphery of the building constructed using the concrete to be cured by heating and prevents leakage of the electromagnetic wave to the outside of the building. Electromagnetic waves can be prevented from affecting equipment and the human body existing outside the building.

According to the fourth aspect of the present invention, since the electromagnetic wave shielding member is constituted by using the electromagnetic wave absorbing material and absorbs the electromagnetic wave, the electromagnetic wave reflected by the electromagnetic wave shielding member leaks to a portion other than the heating and curing part, and the electromagnetic wave shielding member may not be used. Leakage to the outside of the object can be prevented, so that the electromagnetic wave shielding member can efficiently shield electromagnetic waves.

According to the fifth aspect of the present invention, a heating control member for inhibiting the transmission of electromagnetic waves is provided between the concrete and the electromagnetic wave irradiation means, and the intensity of the electromagnetic waves transmitted through the heating control member is controlled by the heating control member. Therefore, the degree of temperature rise of the concrete on the back side of the heating control member can be controlled.

According to the sixth aspect of the present invention, the heat generated by the electromagnetic wave absorbing and heating member or the electromagnetic wave absorbing and heating member is shielded by the heat insulating member. Therefore, for example, when the heat insulating member is disposed on the surface of concrete, the heat generated by the electromagnetic wave absorbing and heating material or the electromagnetic wave absorbing and heating member is prevented from leaking to the outside of the concrete. Can be.

On the other hand, for example, when this heat insulating member is disposed inside concrete, the electromagnetic wave absorbing and heating material or the heat generated by the electromagnetic wave absorbing and heating member is prevented from leaking from the disposed portion. Can be increased.

According to the seventh aspect of the present invention, the electromagnetic wave radiated from the electromagnetic wave radiating means is irradiated by the electromagnetic wave radiating means or the electromagnetic wave absorbing and radiating member by the reflecting member arranged on the surface of the concrete or inside the concrete. Since the light is reflected in the direction and is absorbed again, the electromagnetic wave absorbing and heating member or the electromagnetic wave absorbing and heating member increases the electromagnetic wave absorption efficiency, and therefore, the energy efficiency can be increased.

According to the eighth aspect of the present invention, the mixing amount of the electromagnetic wave absorbing and heating material into the concrete or the coating amount of the electromagnetic wave absorbing and heating member on the concrete surface is adjusted for each portion of the concrete. The amount of heat generated by the electromagnetic wave absorbing and heating material or the electromagnetic wave absorbing and heating member can be adjusted for each part, and therefore, the amount of heating can be adjusted for each part of the concrete.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a building according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an electromagnetic wave irradiation device.

FIG. 3 is a sectional view of concrete.

FIG. 4 is a surface view of concrete.

FIG. 5 is a plan view of the electromagnetic wave shielding member.

FIG. 6 is a sectional view of concrete according to a modification of the embodiment of the present invention.

[Explanation of symbols]

 12 Concrete 14 Electromagnetic Wave Irradiation Device (Electromagnetic Wave Irradiation Means) 28 Carbon Fiber (Electromagnetic Wave Absorption Heating Material) 32 Insulation Member 38 Reinforcement Bar (Reflection Member) 44 Electromagnetic Wave Absorption Heating Panel (Electromagnetic Wave Absorption Heating Member) 54 Conductive Mesh (Heating Control Member) 56 conductive board (electromagnetic wave shielding member) 57 conductive sheet (electromagnetic wave shielding member)

Continued on the front page (72) Inventor Sadatoshi Ohno 1-5-1, Otsuka, Inzai, Chiba Pref.

Claims (8)

[Claims] An electromagnetic wave absorbing and heating material that absorbs electromagnetic waves and generates heat is mixed into concrete, and electromagnetic waves are radiated from outside the concrete by electromagnetic wave irradiating means for irradiating electromagnetic waves, and the irradiated electromagnetic waves are applied to the electromagnetic wave absorbing and heating material. Absorb and generate heat, heat and cure the concrete by the heat generated by the electromagnetic wave absorbing and heating material, and, at that time, install an electromagnetic wave shielding member that shields the electromagnetic wave to prevent electromagnetic waves from being transmitted to portions other than the region where the heat is cured. A method for heating concrete, wherein leakage is prevented. 2. An electromagnetic wave absorbing and heating member that absorbs electromagnetic waves and generates heat is coated on concrete, and electromagnetic waves are radiated from outside the concrete by electromagnetic wave irradiating means for irradiating the electromagnetic waves, and the irradiated electromagnetic waves are applied to the electromagnetic wave absorbing and heating members. Absorb and generate heat, heat and cure the concrete by the heat generated by the electromagnetic wave absorbing and heating member, and, at that time, install an electromagnetic wave shielding member for shielding the electromagnetic wave to prevent the electromagnetic wave from being transmitted to a portion other than the portion to be heated and cured. A method for heating concrete, wherein leakage is prevented. 3. The electromagnetic wave shielding member is installed on the outer periphery of a building constructed using the concrete to prevent leakage of the electromagnetic wave to the outside of the building. Item 4. The method for heating concrete according to Item 2. 4. The concrete heating method according to claim 1, wherein the electromagnetic wave shielding member is formed using an electromagnetic wave absorbing material, and absorbs the electromagnetic wave. 5. A heating control member for preventing transmission of electromagnetic waves is provided between the concrete and the electromagnetic wave irradiation means,
The method for heating concrete according to any one of claims 1 to 4, wherein the intensity of electromagnetic waves transmitted through the heating control member is controlled by the heating control member. 6. A heat insulating member is provided on the surface of the concrete or inside the concrete, and the heat insulating member blocks heat generated by the electromagnetic wave absorbing and heating material or the electromagnetic wave absorbing and heating member. The method for heating concrete according to any one of claims 1 to 5. 7. A reflecting member for reflecting electromagnetic waves is provided on the surface of the concrete or inside the concrete,
The electromagnetic wave emitted from the electromagnetic wave irradiating means by the reflection member is reflected toward the electromagnetic wave absorbing and heating material or the electromagnetic wave absorbing and heating member and is absorbed again. The method for heating concrete according to the above. 8. The method according to claim 1, wherein the amount of the electromagnetic wave absorbing and heating material mixed into the concrete or the amount of the electromagnetic wave absorbing and heating member coated on the concrete surface is adjusted for each part of the concrete. 1 to 7
The method for heating concrete according to any one of the above.