A device for scraping concrete structures and a method for scraping using the device.

Abstract

The present invention provides a surface preparation device for reinforced concrete structures and a surface preparation method using the same device, which allows for the smooth removal of mortar and rust adhering to exposed reinforcing bars after chipping away deteriorated reinforced concrete during cross-section repair work on existing reinforced concrete structures, without generating noise or dust that would worsen the working environment, and thus eliminating the need to take special environmental protection measures such as noise reduction measures for nearby residents, especially when working in urban areas. [Solution] The invention is characterized by a configuration that includes a laser irradiator that irradiates a target object with a laser, and a reflector that is detachably attached to the laser irradiator and reflects the emitted laser, and the reflector allows the laser to be irradiated to the back side of the target object, thereby enabling the front and back sides of the target object to be scraped.

Description

Technical Field

[0001] The present invention relates to a scabbling apparatus for concrete structures and a scabbling method using the scabbling apparatus, and particularly relates to a laser scabbling apparatus for existing reinforced concrete structures and a laser scabbling method using the laser scabbling apparatus.

Background Art

[0002] For example, in cross-section restoration work on existing reinforced concrete structures, after chipping away deteriorated reinforced concrete, the embedded reinforcing bars are exposed, and the mortar, rust, and the like adhering to the exposed reinforcing bars are conventionally removed using a jet chisel or the like.

[0003] However, since the conventional removal work often generates noise and dust, complaints may be received for construction work in urban areas. Therefore, there has been a demand for a scabbling apparatus and a scabbling method that can suppress the generation of noise and dust as much as possible in the aforementioned removal work.

[0004] Here, the conventional cross-section restoration work for existing reinforced concrete structures will be described. Normally, chipping is performed using an electric hammer or the like to expose the embedded reinforcing bar portion, and then the mortar adhering around the cylindrical reinforcing bar is removed using a jet chisel or the like. Then, as the final finishing step, a wire brush or the like is used to remove the remaining mortar and rust on the reinforcing bars for finishing.

[0005] However, the conventional scabbling method using a jet chisel performed after chipping generates noise and dust, which deteriorates the working environment, and in particular, for work in urban areas, there is a problem that environmental conservation measures such as noise countermeasures for neighboring residents must be implemented. Accordingly, the inventors of the present application have started the invention of a laser scabbling apparatus and a laser scabbling method that can suppress the generation of noise and dust and thus do not degrade the working environment.

[0006] As prior art using lasers, there is Japanese Patent Publication No. 2023-108359, which applies lasers to the surface cleaning of girder flanges. However, this technology is limited to the surface of girder flanges and cannot be applied to the surface cleaning of embedded reinforcing bars around the entire circumference in cross-sectional repair work of reinforced concrete structures. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2011-105474 [Patent Document 2] Japanese Patent Application Publication No. 11-336172 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The present invention was devised to solve the aforementioned conventional problems, and aims to provide a surface preparation device for reinforced concrete structures and a surface preparation method using the surface preparation device, which allows for the smooth removal of mortar and rust adhering to exposed reinforcing bars after chipping away deteriorated reinforced concrete in cross-sectional repair work on existing reinforced concrete structures, without generating noise or dust that would worsen the working environment, and thus eliminating the need to take special environmental protection measures such as noise countermeasures for nearby residents, especially when working in urban areas. [Means for solving the problem]

[0009] The present invention The system comprises a laser irradiator that irradiates a target object with a laser, and a reflector that is detachably attached to the laser irradiator and reflects the emitted laser, thereby enabling irradiation of the back side of the target object and allowing for surface cleaning of both the front and back sides of the object. It is characterized by the following: or The reflector is configured to allow adjustment of the reflection angle, so that an appropriate reflection angle can be selected to perform proper scraping on the back side of the object to be scraped. It is characterized by the following: or The object to be scraped is the reinforcing steel exposed after the concrete of a reinforced concrete structure has been chipped away. It is characterized by the following: or The laser irradiator is equipped with an air injection member that sprays air toward the reflector and / or the laser irradiator. It is characterized by the following: or The laser irradiator is equipped with a non-contact thermometer capable of measuring the temperature of the object being scraped during laser irradiation. It is characterized by the following: or After chipping away the concrete of a reinforced concrete structure, the laser scraping device described in claims 1 to 5 is used to laser scrape the surface side of the exposed reinforcing bars, then the reflector is attached to the laser irradiator and the back side of the reinforcing bars is laser scraped, or the back side of the reinforcing bars is scraped first with the laser reflected by the reflector, then the reflector member is removed and the surface side of the reinforcing bars is laser scraped, and during the laser scraping, a threshold temperature is set so as not to impair the physical properties of the reinforcing bars during scraping, and the temperature of the reinforcing bars is continuously measured so as not to exceed the threshold temperature. It is characterized by the following: or After chipping away the concrete of a reinforced concrete structure, the surface side of the exposed reinforcing bars is laser-cleaned using the laser scraping device described in claims 1 to 5, then the back side of the reinforcing bars is laser-cleaned by attaching the reflector to the laser irradiator, or the back side of the reinforcing bars is laser-cleaned first and then the surface side of the reinforcing bars, and during the laser scraping, air is sprayed from an air injection member toward the reflector and / or the laser irradiator, and a threshold temperature is set so as not to impair the physical properties of the reinforcing bars, and the temperature of the reinforcing bars is continuously measured so as not to exceed the threshold temperature. It is characterized by the following: [Effects of the Invention]

[0010] According to the present invention, in cross-section repair work or the like on existing reinforced concrete structures, when performing work to remove mortar and rust adhering to exposed reinforcing bars after chipping away deteriorated reinforced concrete, noise and dust are not generated to degrade the working environment. In particular, there is no need to implement special environmental conservation measures such as noise countermeasures for neighboring residents during work in urban areas, and the present invention provides the excellent effect that it is possible to provide a descaling device for reinforced concrete structures that enables smooth removal of mortar and rust adhering to exposed reinforcing bars, and a descaling method using the descaling device. [Brief Description of the Drawings]

[0011] [Figure 1] This is a configuration explanatory diagram illustrating the configuration of a laser descaling device according to the present invention. [Figure 2] This is a configuration explanatory diagram illustrating a configuration in which a reflector member is attached to the laser descaling device. [Figure 3] This is an explanatory diagram illustrating the configuration of the reflector portion. [Figure 4] This is an explanatory diagram illustrating a state where the reflector member is attached to perform laser descaling on the back side of a reinforcing bar. [Figure 5] This is a configuration explanatory diagram illustrating the configuration of a laser descaling device to which an air injection member is attached. [Figure 6] This is work on the back side of a railway viaduct, and is an explanatory diagram illustrating a state where laser descaling is performed on the surface side of exposed reinforcing bars. [Figure 7] This is work on the back side of a railway viaduct, and is an explanatory diagram illustrating a state where laser descaling is performed on the back side of exposed reinforcing bars with the reflector member attached. [Figure 8] This is an explanatory diagram illustrating a state where reinforcing bars have been descaled by the present invention. [Modes for Carrying Out the Invention]

[0012] The present invention will be described below based on the embodiments shown in the figures. The present invention relates to a surface preparation device and a surface preparation method using the surface preparation device, which, for example, uses an electric hammer to chip away at the concrete of an existing concrete structure, and then performs surface preparation work to remove rust, mortar, etc., adhering to the outer surface of the reinforcing bars 4 exposed from the concrete by the chipping.

[0013] In this invention, first, in cross-sectional repair work on an existing reinforced concrete structure, the concrete is chipped away until the entire circumference of the reinforcing bars 4 embedded inside the existing reinforced concrete is exposed.

[0014] Next, after chipping away the concrete until the entire circumference of the reinforcing bar 4 is exposed, a surface preparation process is performed in which rust and residual mortar around the entire circumference of the reinforcing bar 4 are removed by laser irradiation.

[0015] The laser scraping device 1 of the present invention is used for scraping the reinforcing bars 4 by the aforementioned laser irradiation operation.

[0016] As shown in Figures 1(a) and 1(b), the laser scraping device 1 according to the present invention comprises a laser irradiator 2 and a laser oscillator 3. The laser irradiator 2 of the present invention is lightweight and compact so that a worker can easily hold it in their hand and perform scraping work even in narrow spaces. The laser emitted by the laser oscillator 3 is irradiated from the laser light-emitting part 7 of the laser irradiator 2 onto the area around the exposed reinforcing bar 4, thereby removing rust and residual mortar present all around the reinforcing bar 4.

[0017] In other words, the laser irradiator 2 in the present invention is configured to include a rod-shaped irradiator body 5 and a laser head 6 having a laser light-emitting part 7 attached to the tip of the irradiator body 5. Furthermore, the rear end of the irradiator body 5 is configured as a handle part 8 so that a worker can easily grip it and irradiate the reinforcing bar 4 with the laser. The worker can grip the handle part 8 and irradiate the entire surface of the reinforcing bar 4 from the laser head 6 at any angle.

[0018] Furthermore, the laser used in this invention is primarily a pulsed laser, which is considered to have relatively little thermal influence, and is used as a 300W laser. The laser used in this invention can be used with 300W or less, or more, by appropriately setting the laser irradiation conditions.

[0019] However, the aforementioned laser irradiator 2 cannot irradiate the back side of the exposed reinforcing bar 4 with a laser. Therefore, in this invention, the laser irradiator 2 is configured to allow the reflective member 9 to be detachably attached.

[0020] Figures 2 to 4 show its configuration. In the figures, the reflector member 9 is composed of a strip-shaped reflector holder 10 and a reflector part 11 attached to the tip of the reflector holder 10. Here, as shown in Figure 3, the reflector part 11 is composed of a rectangular reflector case 12 and a reflector 13 mounted inside the reflector case 12. The reflector part 11 is attached to the tip of the reflector holder 10, and is mounted in a way that allows angle adjustment so that the laser emitted from the laser light-emitting unit 7 is reflected from the reflector 13 and irradiated to any point on the back side, i.e., the outer circumferential surface of the exposed reinforcing bar 4.

[0021] Here, the reflector member 9 is configured to be detachably attached to the laser irradiator 2. That is, when scraping the outer circumferential surface on the back side of the exposed reinforcing bar 4, the reflector member 9 is attached and scraping is performed. However, when scraping the surface side of the reinforcing bar instead of the back side, the reflector member 9 would get in the way if it were attached. Therefore, when scraping the surface side of the reinforcing bar 4 with a laser, the reflector member 9 is configured to be removed from the laser irradiator 2. That is, as can be seen from the figure, a fitting hole 14 is formed at the tip of the reflector member 9 to fit into the tip side of the rod-shaped reflector holding part 10, and the tip of the reflector holding part 10 is inserted through the fitting hole 14 so that the reflector member 9 can be detachably attached. However, the detachable attachment configuration is not limited to the above configuration.

[0022] Next, Figure 5 shows another embodiment of the laser surface preparation apparatus 1. As can be seen from Figure 5, the laser irradiator 2 is provided with an air injection member 15 that sends out air. The air injection member 15 may be configured to have a first injection section that blows air onto the reflector 13, a second injection section that blows air onto the hollow part of the reflector holding section 10, for example, which is configured in a cylindrical shape, a third injection section that blows air onto the outer surface of the reflector holding section 10, or it may be provided with any two of the above injection sections or any one of the above injection sections.

[0023] In this way, by providing the air injection member 15 and injecting air to each location, the cleanliness of the reflector 13 can be maintained. That is, there is a possibility that mortar and dust removed by laser irradiation may adhere to the reflector 13 and reduce the irradiation performance, but as a countermeasure, by irradiating the laser while blowing air onto the reflector 13, the adhesion of removed materials to the reflector 13 can be prevented, and stable laser surface preparation becomes possible.

[0024] Furthermore, by spraying air onto the reflector holder 10, excessive heating of the reflector holder 10 itself can be prevented, thereby enabling workers to work safely while gripping it.

[0025] Furthermore, the present invention employs a configuration in which a non-contact thermometer 16, such as an infrared radiation thermometer, is used to measure the surface temperature of the reinforcing bar 4 in real time, for example, so as not to impair the physical properties of the reinforcing bar 4, and the laser is irradiated while the temperature is being monitored. For example, the laser is irradiated so that the surface temperature of the reinforcing bar 4 does not exceed approximately 400°C during the laser irradiation.

[0026] Furthermore, the system can be configured to input temperature measurement data from a non-contact thermometer 16, such as an infrared radiation thermometer, into a computer 17, and to send out warning information when the temperature data reaches a set threshold, for example, approximately 400°C.

[0027] In other words, in this invention, by monitoring the surface temperature of the reinforcing bar 4 so as not to exceed a predetermined threshold, for example, about 400°C, while irradiating it with a laser, it is possible to prevent deterioration of the physical properties of the reinforcing bar 4 due to excessive heating by the laser.

[0028] Next, we will show an example of a work procedure using the present invention on an existing reinforced concrete structure, such as a railway viaduct.

[0029] First, for example, an electric hammer is used to chip away at the concrete of an existing concrete structure, such as the underside of a railway overpass. This chipping exposes the outer surface of the embedded reinforcing bars 4. Then, a laser irradiator 2 is used to perform a surface scraping operation on the exposed outer surface of the reinforcing bars 4 using laser irradiation. Next, a reflector member 9 is attached, and the laser reflected by the reflector 13 is irradiated onto the back side of the exposed outer surface of the reinforcing bars 4, performing a surface scraping operation on the back side of the outer surface of the reinforcing bars 4. The reflector 13 is configured so that the reflection angle can be easily changed, and the laser is constantly reflected at the appropriate reflection angle, allowing the back side of the outer surface of the reinforcing bars 4 to be scraped.

[0030] Here, the order in which the laser is irradiated from the outer surface side of reinforcing bar 4 or from the inner surface side of reinforcing bar 4 is not limited. Depending on the site conditions, either order is acceptable.

[0031] Laser irradiation can weaken the mortar and other materials adhering to the outer surface of the reinforcing bar 4, causing the adhering mortar to eventually peel off from the reinforcing bar 4.

[0032] Furthermore, it has been confirmed that the target objects, concrete and reinforcing bars 4, do not undergo any alteration due to laser irradiation.

[0033] Furthermore, the present invention has the advantage that the machinery used, such as the laser irradiator 2, is lightweight, and that it can adequately ensure safety during work, especially on elevated work platforms such as the underside of railway viaducts. In addition, the present invention has the advantage of not requiring a special work environment or special skills.

[0034] Furthermore, to prevent mortar or debris from adhering to the reflector 13 during laser irradiation, the system is configured to allow air to be sprayed onto the reflector 13 by an air injection member 15. In addition, the system is configured to spray air to prevent the reflector holding part 10 from overheating.

[0035] Furthermore, a non-contact thermometer 16, such as an infrared radiation thermometer, is used to measure the surface temperature of the reinforcing bars 4 in real time, ensuring that the physical properties of the reinforcing bars 4 are not impaired. The system is controlled to prevent the temperature from exceeding a set threshold temperature for each reinforcing bar 4.

[0036] The surface preparation work in this invention is now complete, however, the outer surface of the reinforcing bar 4 that has been prepared using a brush may be given a final finishing touch.

[0037] Figure 8 shows the state after the entire outer surface of the reinforcing bar 4 has been scraped using the present invention. It can be seen that the outer surface of the reinforcing bar 4 has been scraped to a state where no rust or mortar is attached at all. Moreover, with the laser scraping device and laser scraping method of the present invention, the noise level during operation can be reduced to a very low level, and the work can be carried out without the scattering of dust and debris as in conventional methods. [Explanation of symbols]

[0038] 1. Laser scraping device 2. Laser irradiator 3. Laser Oscillator 4 Reinforcement bars 5. Laser irradiator unit 6 Laser Heads 7. Laser light-emitting section 8. Handle 9 Reflector Member 10 Reflector holding part 11 Reflector section 12 Reflector Cases 13 Reflector 14 mounting holes 15 Air injection member 16 Non-contact thermometer

Claims

1. The system comprises a laser irradiator that irradiates a target object with a laser, and a reflector that is detachably attached to the laser irradiator and reflects the emitted laser, thereby enabling irradiation of the back side of the target object and allowing for surface cleaning of both the front and back sides of the object. A laser scraping apparatus characterized by the following features.

2. The reflector is configured to allow adjustment of the reflection angle, so that an appropriate reflection angle can be selected to perform proper scraping on the back side of the object to be scraped. The laser scraping apparatus according to claim 1, characterized in that it is a laser scraping apparatus.

3. The object to be scraped is the exposed reinforcing steel of a reinforced concrete structure. The laser scraping apparatus according to claim 1, characterized in that it is a laser scraping apparatus.

4. The laser irradiator is equipped with an air injection member that sprays air toward the reflector and / or the laser irradiator. The laser scraping apparatus according to claim 1, characterized in that it is a laser scraping apparatus.

5. The laser irradiator is equipped with a non-contact thermometer capable of measuring the temperature of the object to be scraped during laser irradiation. The laser scraping apparatus according to claim 1, characterized in that it is a laser scraping apparatus.

6. After chipping away the concrete of a reinforced concrete structure, the laser scraping device described in claims 1 to 5 is used to laser scrape the surface side of the exposed reinforcing bars, then the reflector is attached to the laser irradiator and the back side of the reinforcing bars is laser scraped, or the back side of the reinforcing bars is scraped first with the laser reflected by the reflector, then the reflector member is removed and the surface side of the reinforcing bars is laser scraped, and a threshold temperature is set during the laser scraping so as not to impair the physical properties of the reinforcing bars during scraping, and the temperature of the reinforcing bars is continuously measured so as not to exceed the threshold temperature. A laser surface preparation method characterized by the following features.

7. After chipping away the concrete of a reinforced concrete structure, the surface side of the exposed reinforcing bars is laser-cleaned using the laser scraping device described in claims 1 to 5, then the back side of the reinforcing bars is laser-cleaned by attaching the reflector to the laser irradiator, or the back side of the reinforcing bars is laser-cleaned first and then the surface side of the reinforcing bars is laser-cleaned, and during the laser scraping, air is sprayed from an air injection member toward the reflector and / or the laser irradiator, and a threshold temperature is set so as not to impair the physical properties of the reinforcing bars, and the temperature of the reinforcing bars is continuously measured so as not to exceed the threshold temperature. A laser surface preparation method characterized by the following features.

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