Pillar structure inspection system and inspection method

Abstract

To provide a photographing medium, a soft case, an inspection system and an inspection method that are not damaged even at a location where an attachment is attached to a columnar structure and that can obtain a clear image of the inside of the columnar structure. [Solution] The imaging medium 3 comprises an imaging plate made of a plastic plate coated with a stimulable phosphor, and a soft case that is transparent to X-rays and that houses and protects the imaging plate, and both the imaging plate and the soft case are formed so that they can be deformed to fit the shape of the reinforced concrete column P.

Description

[Technical Field]

[0001] The present invention relates to a columnar structure. Inspection The present invention relates to an inspection system and an inspection method. [Background technology]

[0002] A method for non-destructively inspecting whether or not the internal rebars of a reinforced concrete column are broken is being used. For example, Patent Document 1 discloses a non-destructive inspection device that has a bendable imaging panel for detecting X-rays and a bendable shielding plate for blocking X-rays. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-3426 Summary of the Invention [Problem to be solved by the invention]

[0004] The nondestructive testing device of Patent Document 1 can reduce the distance between the imaging panel and a reinforced concrete pillar by bending the imaging panel. The imaging panel is composed of a flat panel detector with numerous photodiodes and pixel circuits driving each photodiode arranged on a resin substrate. This limits the direction in which the imaging panel can be bent, making it difficult to bend the imaging panel properly in areas where the reinforced concrete pillar is fitted with attachments such as metal bands or electrical wires. Furthermore, forcibly bending the imaging panel can damage the photodiodes and pixel circuits. This problem is not limited to inspecting the internal rebar of reinforced concrete pillars, but also exists when inspecting other columnar structures such as steel pipe pillars.

[0005] The present invention has been made based on the above background, and is capable of obtaining clear images of the inside of a columnar structure without damaging the columnar structure even when an attachment is attached to the columnar structure. TestThe object of the present invention is to provide an inspection system and an inspection method. [Means for solving the problem]

[0006] In order to achieve the above object, the present invention Inspection System teeth, An inspection system for inspecting whether or not internal rebars of reinforced concrete columns are broken, comprising: an imaging medium in which an imaging plate is housed in a soft case attached to the reinforced concrete pillar and formed to be able to transmit radiation; a radiation generating device that is installed facing the imaging medium across the reinforced concrete pillar and that radiates radiation radially; the radiation generating device is disposed away from the reinforced concrete pillar so that radiation passes through all internal reinforcing bars present in the reinforced concrete pillar and is directed toward the imaging medium; The imaging medium is formed so as to detect radiation that is irradiated from the radiation generating device and transmitted through each internal reinforcing bar when the imaging medium is attached by being deformed to fit the outer wall of the reinforced concrete column. It is being done. [Effects of the Invention]

[0007] According to the present invention, even in the area where an attachment is attached to the columnar structure, no damage occurs and it is possible to obtain a clear image of the inside of the columnar structure. Test Inspection systems and methods can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing a configuration of an inspection system according to an embodiment of the present invention; [Figure 2] 1A and 1B are diagrams each showing the configuration of an imaging medium according to an embodiment of the present invention. [Figure 3] FIG. 10 is another diagram showing the configuration of the inspection system according to the embodiment of the present invention. [Figure 4] 1 is a cross-sectional view showing how an internal reinforcing bar of a reinforced concrete column is photographed using an inspection system according to an embodiment of the present invention. [Figure 5] 10A and 10B are diagrams for explaining a method for determining whether an internal reinforcing bar is located in front of or behind an X-ray generator in an image captured by an inspection system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a photographing medium, a soft case, an inspection system, and an inspection method for a columnar structure according to an embodiment of the present invention will be described in detail with reference to the drawings. In each drawing, the same or equivalent parts are designated by the same reference numerals.

[0010] The inspection system according to the embodiment is a system for photographing the inside of a columnar structure by irradiating X-rays from an X-ray generator toward the columnar structure and detecting the X-rays that have passed through the columnar structure with an imaging medium. By checking the state of the inside of the columnar structure depicted in the photographed image read from the imaging medium, a user can determine whether corrosion or damage exists inside the columnar structure.

[0011] The columnar structure according to the embodiment is a columnar structure that is installed on the ground and supports a support object, such as an electric wire, above the ground. The columnar structure according to the embodiment is, for example, a reinforced concrete column or a steel pipe column. The following describes an example of inspecting a reinforced concrete column to see if the internal rebar of the reinforced concrete column is broken.

[0012] A reinforced concrete pole is a long, slender structure made of reinforced concrete, and is used, for example, as a utility pole for installing electric wires. A reinforced concrete pole comprises a cylindrical concrete body and a plurality of internal reinforcing bars arranged in the circumferential direction of the reinforced concrete body and each extending in the longitudinal direction. The outer diameter of a reinforced concrete pole may gradually increase from the end to the butt end, or may be constant.

[0013] Next, the configuration of an inspection system 1 according to an embodiment will be described with reference to FIGS. As shown in Fig. 1, the inspection system 1 is installed facing a reinforced concrete column P and includes an X-ray generator 2 that generates X-rays that pass through the reinforced concrete column P, and an imaging medium 3 that is installed together with the X-ray generator 2 to sandwich the reinforced concrete column P. The pair of the X-ray generator 2 and the imaging medium 3 is installed so as to face each other with the reinforced concrete column P in between.

[0014] The X-ray generator 2 is a radiation generating device that generates X-rays, an example of radiation, and irradiates them toward an external target. The X-ray generator 2 is configured to be portable by the user and is installed on a stand 2A or the like that is matched to the height of the area to be inspected. The X-ray generator 2 includes an X-ray tube. In the X-ray tube, electrons emitted from a filament collide with the target, thereby generating X-rays from the target. The X-ray generator 2 may be externally powered or battery-powered.

[0015] When inspecting a location where an attachment is installed on a reinforced concrete pillar P, it is advisable to increase the tube voltage in the X-ray generator 2 or increase the irradiation time while taking into consideration the effective dose to the worker in order to ensure the equivalent dose required for imaging. The attachment to the reinforced concrete pillar P is, for example, a metal band B (electric pole band) attached around the reinforced concrete pillar P. The following describes an example in which band B is used as the attachment.

[0016] The imaging medium 3 is irradiated by the X-ray generator 2 and detects the X-rays that pass through the reinforced concrete column P. The imaging medium 3 is a deformable imaging medium formed in a plate shape, and can be manually bent to fit the outer wall of the reinforced concrete column P. Furthermore, since the imaging medium 3 has no electronic components or circuits attached, it can be deformed into any shape. Therefore, even if a band B is attached to the reinforced concrete column P, it can be deformed to fit the shape of the band B, and the part of the imaging medium 3 that is not in contact with the band B can also be made to fit the surface of the reinforced concrete column P.

[0017] 2, the imaging medium 3 includes an imaging plate (IP) 3A and a soft case 3B that is formed to be able to transmit radiation and that houses and protects the imaging plate 3A. The imaging medium 3 may be attached to the surface of the reinforced concrete column P with adhesive tape or rope.

[0018] The imaging plate 3A is a thin, flexible plate that can record an image of the object to be detected when irradiated with radiation. The imaging plate 3A is a plastic film coated with a phosphor that produces photostimulable luminescence (stimulable phosphor). After luminescence due to irradiation with radiation has ceased, stimulable phosphors have the property of emitting light again when irradiated with light of a longer wavelength than the luminescent wavelength. The plastic film is formed, for example, from polyethylene terephthalate resin, and the stimulable phosphor can be applied or vapor-deposited onto this plastic film.

[0019] The soft case 3B is a protective case that is deformable to fit the shape of the reinforced concrete column P and protects the imaging plate 3A from scratches. The soft case 3B is made of a flexible sheet that is transparent to radiation. Since the imaging medium 3 is used outdoors even in rainy weather, the sheet is made of a dustproof, waterproof, and weather-resistant material, such as rubber or a thermoplastic elastomer (e.g., silicone rubber). The thickness of the sheet is set to a level that does not hinder the deformation of the imaging plate 3A and is not easily damaged even when repeatedly bent. The thickness of the sheet is, for example, in the range of 0.1 mm to 5 mm, preferably in the range of 1 mm to 2 mm, and is 1.3 mm, for example.

[0020] The soft case 3B is shaped like an envelope, for example. Specifically, the soft case 3B is made up of two overlapping sheets, with the bottom and both side edges sealed, and an opening at the top for inserting and removing the imaging plate 3A. A flap is provided at the top of the soft case to seal the opening when closed.

[0021] 3, the examination system 1 further includes a computed radiography (CP) 4 and a display device 5. The computed radiography 4 and the display device 5 are communicatively connected via a wired or wireless communication circuit.

[0022] The computed radiography 4 is a scanner that generates photostimulable fluorescence by irradiating an imaging plate 3A irradiated with X-rays with excitation light, and reads the image recorded on the imaging plate 3A. In the computed radiography 4, the imaging plate 3A is scanned with excitation light, and the light generated by irradiation with laser light is converted into an analog signal by an optical sensor, which then converts the analog signal into a digital signal. The digital signal is then subjected to signal processing to generate a two-dimensional captured image. The excitation light is, for example, laser light, and the optical sensor is, for example, a photomultiplier tube.

[0023] The display device 5 is, for example, a general-purpose computer. The display device 5 includes an operation device, a display, an input / output interface, a memory, and a processor, and by executing a program stored in the memory, the input / output interface stores data of the captured image received from the computed radiography device 4, and displays the captured image on the display based on an operation signal from an operation device operated by a user.

[0024] The inspection system 1, with the above-described configuration, can be curved to fit the curved surface of the reinforced concrete column P. As a result, a large number of rebars can be imaged in one shot, reducing the number of shots required. In the example of Figure 4, the X-ray generator 2 is installed away from the reinforced concrete column P so that the X-rays can pass through all of the internal rebars, thereby imaging all eight of the internal rebars. Furthermore, because the gap between the imaging plate 3A and the reinforced concrete column P is small, clear images can be obtained even at both ends of the imaging plate 3A. Clear images can also be obtained even when a band B is installed on the reinforced concrete column P. Furthermore, because the gap between the imaging plate 3A and the reinforced concrete column P is small, it is easy to attach the imaging medium 3 to the reinforced concrete column P. The above is the configuration of the inspection system 1.

[0025] Next, a method for determining the imaging procedure using the inspection system 1 according to the embodiment will be described. The area to be inspected by the inspection system 1 is an area where cracks or breaks have been confirmed on the surface of the reinforced concrete column P. The imaging direction and the number of times to take images are determined after understanding the arrangement of the internal rebars in the area to be inspected from a reinforcement drawing. The imaging direction indicates where around the reinforced concrete column P the pair of X-ray generator 2 and imaging medium 3, which are installed facing each other, should be installed.

[0026] When photographing using the inspection system 1 according to the embodiment, one photograph is generally taken. In one photograph, the arrangement of the internal rebars is taken into consideration, and the pair of the X-ray generator 2 and the photographing medium 3 is positioned so that all the rebars on both the front and back sides of the X-ray generator 2 can be photographed in one photograph. At this time, the photographing medium 3 is installed so as to minimize the gap between it and the reinforced concrete column P and the band B. For example, when photographing a portion of the reinforced concrete column P to which the band B is attached, the photographing medium 3 is positioned to avoid the bolt protrusions of the band B as much as possible.

[0027] In the image obtained by this procedure, the internal rebars on the front side of the X-ray generator 2 appear thicker than the internal rebars on the back side, as shown in Figure 5. This is because the X-rays emitted from the X-ray generator 2 are emitted radially, so the internal rebars that are closer to the X-ray generator 2 appear larger in the image. This makes it possible to identify the circumferential position of each internal rebar from a single image.

[0028] Furthermore, if, after one photographing, there are rebars that could not be photographed due to the influence of band B, the pair of X-ray generator 2 and photographing medium 3 can be rotated within a range of less than 90° around the longitudinal axis of the reinforced concrete column P and a second photographing can be performed.

[0029] On the other hand, if it is expected that the quality of the captured image will be reduced in a single shot due to the installation condition of band B, the procedure will be to perform two or more shots from the beginning. An example of a case where a reduction in image quality is expected is when the gap between the imaging plate 3A and the reinforced concrete column P becomes large due to the bolt protrusions of band B. In this case, the first shot is performed in the same manner as the first shot. Next, for the second shot, the pair of the X-ray generator 2 and the imaging medium 3 is rotated within a range of less than 90° around the longitudinal axis of the reinforced concrete column P from the position at the time of the first shot and positioned accordingly. For the third shot, the pair of the X-ray generator 2 and the imaging medium 3 is rotated 180° around the longitudinal axis of the reinforced concrete column P from the position at the time of the first shot and positioned accordingly. The method for determining the imaging procedure has been described above.

[0030] Next, a method for inspecting internal reinforcing bars of a reinforced concrete column P using the inspection system 1 according to the embodiment will be described. It is assumed that the photographing procedure for the reinforced concrete column P has been determined before the inspection method is carried out. First, prepare the imaging medium 3. Specifically, the imaging plate 3A, from which the image has been erased, is stored inside the soft case 3B, and the opening is sealed with a flap, thereby assembling the imaging medium 3.

[0031] Next, the imaging medium 3 is attached while being deformed to fit the shape of the reinforced concrete pillar P and band B so that the imaging direction is determined by the imaging procedure, and the X-ray generator 2 is installed so that it faces the imaging medium 3 across the reinforced concrete pillar P. If sharp attachments such as wires are attached to the area to be imaged, it is preferable to remove these attachments in advance to prevent damage to the soft case.

[0032] Next, an image of the internal rebar of the reinforced concrete column P is taken. Specifically, an image of the internal rebar of the reinforced concrete column P is recorded on the imaging medium 3 by irradiating X-rays from the X-ray generator 2 so that they pass through the reinforced concrete column P and head toward the imaging medium 3.

[0033] Next, the imaging medium 3 is removed from the reinforced concrete pillar P, and the imaging plate 3A is taken out from the soft case 3B.

[0034] Next, the imaging plate 3A is set in the computed radiography 4, and the computed radiography 4 is caused to execute a process of reading an image from the imaging plate 3A. The image read by the computed radiography 4 is sent to the display device 5 and stored in memory.

[0035] By repeating the above procedure according to the number of times of photography determined by the photography procedure, the image of the internal rebar recorded on each imaging plate 3A is converted into a photographed image, and the photographed images for the number of times of photography are sequentially stored in the memory of the display device 5. The user simply reads out the photographed image stored in the memory of the display device 5 and displays it on the display of the display device 5. Then, by referring to one or more photographed images displayed on the display of the display device 5, the user can determine whether or not the internal rebar is fractured at the location to be inspected. The above is the flow of the inspection method.

[0036] As explained above, the imaging medium 3 according to the embodiment comprises an imaging plate 3A, which is a plastic plate coated with a photostimulable phosphor, and a soft case 3B that is formed to be transparent to X-rays and that houses and protects the imaging plate 3A, and both the imaging plate 3A and the soft case 3B are formed to be deformable to fit the curvature of the outer wall of the reinforced concrete column P. Therefore, the imaging medium will not be damaged even in places where attachments such as bands B are attached to the reinforced concrete column P, and clear images of the inside of the reinforced concrete column P can be obtained.

[0037] The present invention is not limited to the above-described embodiment, and the following modifications are possible.

[0038] (Variation) In the above embodiment, X-rays are used as the radiation, but the present invention is not limited to this. For example, depending on the type of reinforced concrete column P, neutron rays or gamma rays may be used as the X-rays.

[0039] In the above embodiment, the X-ray generator 2 is placed on a gantry 2A, but the present invention is not limited to this. For example, the X-ray generator 2 may be placed on a dolly to facilitate transportation.

[0040] In the above embodiment, the soft case 3B is attached to the reinforced concrete column P with adhesive tape or rope, but the present invention is not limited to this. For example, a pair of bands may be attached to both side ends of the soft case 3B, and both ends of the pair of bands may be configured to be detachable with hook-and-loop fasteners or the like, so that the pair of bands and the soft case 3B can be wrapped around the reinforced concrete column P.

[0041] In the above embodiment, the soft case 3B is shaped like an envelope, but the present invention is not limited to this. For example, a zipper may be provided instead of the flap at the top. Also, if dustproofness or waterproofness is not required, the flap at the top of the soft case 3B may be omitted and the soft case may be formed like a bag.

[0042] In the above embodiment, the imaging plate 3A is housed in the soft case 3B, but the present invention is not limited to this. For example, an X-ray film may be housed in the soft case 3B.

[0043] In the above embodiment, the inspection system 1 is used to inspect whether or not the internal rebars of the reinforced concrete column P are broken, but the present invention is not limited to this. For example, the inspection system 1 may be used to inspect whether or not corrosion degradation has occurred inside a steel pipe column. In areas where corrosion degradation has occurred inside a steel pipe column, the thickness of the pipe wall is reduced, making it possible to distinguish these areas from normal areas where corrosion degradation has not occurred in the captured image.

[0044] The above-described embodiments are merely examples, and the present invention is not limited to these. Various embodiments are possible within the scope of the invention as set forth in the claims. The components described in the embodiments and modifications can be freely combined. Furthermore, inventions equivalent to the inventions set forth in the claims are also included in the present invention. [Explanation of symbols]

[0045] 1. Inspection system 2 X-ray generator 3 Filming media 3A Imaging Plate 3B soft case P Reinforced concrete column

Claims

1. An inspection system for inspecting whether or not internal rebars in reinforced concrete columns are broken, comprising: an imaging medium in which an imaging plate is housed in a soft case attached to the reinforced concrete pillar and formed to be able to transmit radiation; a radiation generating device that is installed facing the imaging medium across the reinforced concrete pillar and that radiates radiation radially; the radiation generating device is disposed away from the reinforced concrete pillar so that radiation passes through all internal reinforcing bars present in the reinforced concrete pillar and is directed toward the imaging medium; the imaging medium is formed so as to detect radiation that is irradiated from the radiation generating device and transmitted through each internal reinforcing bar in a state where the imaging medium is deformed and attached to fit the outer wall of the reinforced concrete column, Inspection system.

2. An inspection method for inspecting whether or not internal reinforcing bars of a reinforced concrete column are broken, comprising: a preparation step of preparing an imaging medium by housing an imaging plate in a soft case formed to be able to transmit radiation; an arrangement step of attaching the imaging medium to the reinforced concrete pillar while deforming the imaging medium, and installing a radiation generating device so as to face the imaging medium across the reinforced concrete pillar, thereby arranging the radiation generating device and the imaging medium as a pair; an imaging step of imaging the internal reinforcing bars by irradiating radiation from the radiation generating device so that the radiation passes through the reinforced concrete column and heads toward the imaging medium, In the arranging step, the pair of the radiation generating device and the imaging medium is arranged so that the radiation radially irradiated from the radiation generating device can penetrate all of the internal reinforcing bars present in the reinforced concrete column, and the radiation that has penetrated each of the internal reinforcing bars can be detected by the imaging medium. Testing method.

3. An inspection method for inspecting whether or not internal reinforcing bars of a reinforced concrete column are broken, comprising: a preparation step of preparing an imaging medium by housing an imaging plate in a soft case formed to be able to transmit radiation; a first arrangement step of attaching the imaging medium while deforming it to fit the reinforced concrete pillar, and installing a radiation generating device so as to face the imaging medium across the reinforced concrete pillar, thereby arranging a pair of the radiation generating device and the imaging medium; a first imaging step of imaging a part of the internal reinforcing bars present in the reinforced concrete column by irradiating radiation from the radiation generating device so that the radiation passes through the reinforced concrete column and is directed toward the imaging medium; a second arranging step of rotating the pair of the radiation generation device and the imaging medium arranged in the first arranging step by an angle of less than 90° around an axis extending in the longitudinal direction of the reinforced concrete pillar; a second imaging step of irradiating radiation from the radiation generating device so that the radiation passes through the reinforced concrete column and is directed toward the imaging medium, thereby imaging the internal reinforcing bars that were not imaged in the first imaging step; An inspection method including:

Images