JP2008203275A - Inspection method of concrete, and measurement tool used for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inspection method of a concrete structure capable of accurately inspecting deterioration of concrete by minimizing damage to the concrete structure by the inspection, and facilitating repair after the inspection; and a measurement tool used for it. <P>SOLUTION: The inspection method of deterioration in the depth direction of a concrete structure includes steps of: forming a bored part in the concrete structure; inserting an endoscope into the bored part; and observing deterioration in the bored part through the endoscope. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for inspecting concrete, and more particularly to a method for inspecting a deterioration state inside concrete and a jig used in the method.

  In recent years, in concrete structures such as tunnels and viaducts, there are many accidents in which concrete partially collapses, which is becoming a social problem. The causes of concrete falling are as follows: (1) If cracks occur from poorly constructed parts due to repeated loads, and the cracks develop and concrete loses its integrity, then (2) Reinforcing bars and alkali bones Cracks are generated as deterioration of the material reaction progresses, and the concrete is often dropped as a result of the loss of integrity due to the progress of the cracks.

  In order to prevent the above-mentioned accidents, periodic inspections are carried out by structural managers, etc., but in general, inspection is mainly performed by visual inspection or hammering method, and cracks can be confirmed even if the presence of cracks can be confirmed. It is difficult to accurately ascertain the depth and deterioration status. Moreover, there is a problem that it is difficult to accurately grasp the neutralization inside the concrete and the rusting of the reinforcing bars.

  Various methods have been proposed for diagnosing the above-mentioned crack depth and internal defects, and among them, the non-destructive inspection method is attracting attention. As a conventionally proposed non-destructive inspection method, for example, a method of indirectly measuring an object with ultrasonic waves or electromagnetic waves can be cited. However, the above-described nondestructive inspection methods using ultrasonic waves and electromagnetic waves have problems that measurement accuracy is low and it is difficult to grasp the degree of deterioration in the depth direction.

  In addition, as a method for inspecting a concrete structure, a method for directly observing and diagnosing the degree of deterioration after an inspection portion is exposed by core removal or chipping has been proposed. This inspection method is a method that can most reliably inspect a deteriorated portion. However, the above-mentioned method of directly observing the degree of deterioration requires a large-scale device, has the possibility of damaging the structure, and requires extensive repair after inspection. There are inconveniences.

  In recent years, endoscopes are widely used in the medical field, but the use of endoscopes in the civil engineering field is extremely limited. It is only applied to cases such as borehole cameras and crack inspection in small-diameter pipes, and is expected to be used effectively in the civil engineering field, particularly in various inspections of structures that are difficult to observe from the outside.

  The present invention has been made in view of the above problems, and can easily inspect the important deterioration depth in the inspection of deterioration such as neutralization and alkali-aggregate reaction, crack width corresponding to the deterioration depth, crack It is possible to measure the position and crack direction easily and with high accuracy, and spraying the chemicals necessary for neutralization and observation of alkali-aggregate reaction can be effectively performed with one device, resulting in defects in concrete. By obtaining three-dimensionally, it is possible to perform three-dimensional mapping of defects that makes it possible to judge concrete deterioration in detail, and furthermore, the shape and capacity of the space, such as the shape of voids and the injection state of grout An object of the present invention is to provide a method for inspecting a concrete structure that can be measured easily and with high accuracy, and a measuring jig.

  The above object of the present invention is achieved by providing an inspection method and a measuring jig for a concrete structure of the present invention.

That is, according to the present invention, the step of forming the perforated portion in the concrete structure,
Inserting an endoscope into the perforated part;
Inserting an endoscope having a bendable tip into the perforated part;
Bending the endoscope, and observing bean plate defects in the depth direction of the concrete, cavities, poor filling, floating of tiles and mortar, or rusting through the endoscope;
A measurement jig is inserted through the endoscope, and the three-dimensional image is obtained by processing the three-dimensional image of the bean plate defect, cavity, filling defect, tile or mortar floating, or rusting into a computer. A method for inspecting a concrete structure is provided.

  In addition, according to the present invention, there is provided an inspection method comprising a step of attaching a drug from the endoscope to the inside of the perforated part after the insertion step.

  According to the concrete inspection method of the present invention, a plurality of items can be inspected in the depth direction at the same time using a small-diameter perforated part, and concrete is obtained by providing a plurality of perforated parts and collecting two-dimensional data. It is possible to three-dimensionally map deterioration such as cracks in the structure, beans, filling failure, alkali aggregate reaction, and neutralization. In addition, since the perforated part has a small diameter, repair after inspection is easy without damaging the concrete structure. In addition, it is possible to obtain three-dimensional continuous information about the neutralization and alkali-aggregate reaction that can be diagnosed by coloring with chemicals, not only on the surface but also in the depth direction of the concrete. . Furthermore, the perforated part formed by the method of the present invention can be used as an injection port for an injection after the inspection, and an inspection method excellent in accuracy and simplicity can be provided.

  Hereinafter, the present invention will be described in more detail with reference to the drawings. The method for inspecting a concrete structure according to the present invention can observe deterioration not only on the concrete surface but also on the inside by inserting an endoscope into the perforated part from a perforated part provided in the concrete. It is what. In recent years, such endoscopes have been used as medical instruments that are inserted into the digestive organs of animals and human bodies to examine and treat the affected area from the inside, specifically, medical endoscopes (hereinafter referred to as endoscopes). Developed and used extensively. As such an endoscope, a CCD, a video image scope for transmitting an image by an electrical signal as an image transmission means, a fiberscope for transmitting an image by an optical fiber as an image transmission means, and an optical device using a relay lens as an image transmission means. A rigid endoscope / miniborescope for image transmission can be mentioned, and any type and any image transmission means can be appropriately selected and used. Hereinafter, the present invention will be described using an embodiment in which measurement is performed using a fiberscope type endoscope.

  The features of this endoscope are as follows: (1) The diameter of the insertion portion is as thin as about 10 mm, has a towability, and the tip portion can be observed in an arbitrary direction through operation at the hand portion; (2 ) The image through the endoscope is a high-magnification, clear color image that can be recorded with photos, videos, etc. in addition to observation with the naked eye, (3) Along the optical fiber from the hand to the tip Since a thin and thin tube is inserted, it can be mentioned that the medicine can be sprayed from the tip portion or sampling can be performed directly from the deteriorated portion.

  FIG. 1 shows an endoscope 1 used in the present invention. The endoscope 1 shown in FIG. 1 is inserted into a perforated part provided in a concrete structure, and is bent with a tip optical system 2 and inspection means 3 for performing necessary inspection work inside the perforated part. Part 4, swinging operation part 5, working channel 6, binding member 8 for binding optical fiber bundle 7, and insertion part 9 formed between bending part 4 and binding member 8. Yes. Examples of the inspection means 3 include various scales such as a crack scale, spraying means such as a length measuring jig, a manipulator, and a spray nozzle. A plurality of these inspection means 3 can be provided in one endoscope 1, or an endoscope 1 in which different inspection means 3 are separately attached can be used.

  The optical fiber bundle 7 includes an optical fiber bundle 7a for measurement and an optical fiber bundle 7b for illumination. The optical fiber bundle 7a and the optical fiber bundle 7b are appropriately connected to a device (not shown) so as to perform image measurement and illumination. The insertion portion 9 is made of a sheath formed of a durable material such as Teflon (registered trademark), polyimide, polyethylene, or a tortible metal material, and includes a swing operation portion 5, an optical fiber bundle 7, and a working channel 6. It is formed by accommodating. The sheath is sufficiently flexible and can be bent according to the arrangement of the work place or the like, and is configured to improve workability.

  FIG. 2 is an enlarged view showing a cross section of the bent portion 4 of the endoscope 1. As described with reference to FIG. 1, the bent portion 4 includes the working channel 6, the optical fiber bundle 7 b for illumination, and the swinging tip hardware 10 used for moving the bent portion 4 with respect to the longitudinal axis of the endoscope 1. The fiber sheath 11 surrounds. The optical fiber bundle 7b is formed by bundling a plurality of thinner optical fibers 12, and is used to illuminate the inside of the perforation. The swing tip metal fitting 10 accommodates therein an objective lens 13 and a swing pulling wire 14 for performing a swing motion.

  An optical fiber bundle 7a for obtaining an image (not shown) is connected to the back side of the objective lens 13 in FIG. 2, and is configured to transmit the image to the measuring means. The swing pulling wire 14 moves the swing tip hardware 10 by an operation from the swing operation portion 5, and the bending portion 4 moves in an arbitrary direction in conjunction with this operation.

  The working channel 6 is a hollow towable tube, and can be inserted through various inspection means 3 such as a manipulator (not shown) for ejecting a drug solution or sampling inside the perforation as necessary. It has been made possible. The diameter of the insertion portion of the endoscope 1, the diameters of the optical fiber bundles 7a and 7b, and the diameter of the working channel 6 can be appropriately selected and used as necessary. As such an endoscope 1, the insertion portion 9 is 1.3 mm to 15 mm, the viewing angle is 5 to 90 °, the observation direction is a direct view / focus adjustment method, the illumination is a light guide type, and the allowable bending radius is 50 to 300 mm. It is also possible to use an industrial endoscope with a diameter of about 0.35 mm to 2 mm, a viewing angle of 55 ° to 56 °, an observation depth of 1 to 20 mm, and a swinging portion length of about 20 mm. A medical scope can also be used.

  Examples of the chemical solution that can be used in the present invention include a penetrant flaw detecting agent having various compositions, a cobalt acetate-containing liquid composition, cracks such as phenolphthalein, and a chemical solution for measuring the pH of concrete. It may be a homogeneous solution, or an emulsified and suspended solution. In addition, it is also possible to use a solution of any known chemical that can detect deterioration of a concrete structure.

  FIG. 3 is a front view showing a micro-imaging apparatus 15 that can be used in the present invention. The micro-imaging apparatus 15 shown in FIG. 3 observes an image, an optical system 16 for recording an image propagated from the endoscope 1, an industrial camera (not shown), an image monitor 17, and if necessary. A computer 18 for performing image processing, a keyboard 19 for control input, a video camera 20 for recording observed images, and an illuminating device 21 for illuminating the inside of a concrete perforated part. Yes.

  The operation of the micro-imaging device 15 shown in FIG. 3 will be described. First, illumination light is sent to the endoscope 1 by the illumination device 21 to illuminate the inside of the perforated part. The illuminated image inside the perforated part is imaged by the objective lens 13 attached to the distal end part of the endoscope 1 and sent to the optical system 16 of the micro-imaging apparatus 15 through the optical fiber bundle 7a for image observation. The image magnified by the optical system 16 is formed on an image coupling device such as a CCD (not shown) and then recorded on a recording medium such as a video tape or a hard disk.

  At the same time, the image inside the perforated image formed on the CCD is output on the image monitor 17 to enable visual observation inside the perforated portion. Further, the micro-imaging device 15 is provided with a computer 18 having a central processing unit (CPU). The recorded image sample is subjected to image processing, depth information corresponding to the depth of concrete, and two-dimensional. Based on the information, a three-dimensional imaging process can be performed. However, such image processing can be performed by a processing computer configured separately from the micro-imaging apparatus 15.

  The observation of deterioration inside the concrete structure is performed by inserting the endoscope 1 into a small-diameter perforated portion provided in the concrete constituting the concrete structure using the above-described micro-imaging device 15, and various kinds of poor work and deterioration. It is performed by observing and diagnosing the state visually or by image processing. At this time, since the above-described drilling in the concrete can be provided by a drill having an appropriate diameter, it is possible to provide an inspection method capable of minimizing the damage caused by the inspection on the concrete structure. it can.

  The above-mentioned construction defects and deterioration items are (1) crack position, crack width, crack length, (2) bean plate, cavity, grout filling failure, (3) floating of tiles and mortar, (4) rebar occurrence. Examples thereof include rust, (5) alkali aggregate reaction, and neutralization. According to the present invention, it is possible to inspect these defects with high positional accuracy and while observing the situation with the naked eye.

Examples of the inspection method for concrete structures of the present invention will be described below.
(1) Crack position, crack width, crack length FIG. 4 shows a part of a concrete structure to which the method of the present invention is applied in order to observe the crack position and crack width. In the concrete structure shown in FIG. 4, the cracks 22 are caused by deterioration such as alkali aggregate reaction and neutralization, and only a slight width W is recognized from the outside of the concrete structure. Absent. However, as shown in FIG. 4, the crack 22 extends in the depth direction of the concrete structure, and its precise measurement is extremely important for judging the risk of concrete collapse. In the present invention, the cracks are first drilled with a small-diameter drill at the position where the concrete cracks 22 are observed, and a plurality of drilled portions 23 are formed along the cracks 22.

  The diameter of the perforated part is preferably a diameter that allows the bending part 4 of the endoscope 1 to bend sufficiently at the bending radius as shown by the perforated part 23a. However, by arranging the distal end optical system 2 in the bent portion 4 of the endoscope 1 so as not to be in the length direction of the endoscope 1 but to the inner wall of the perforated portion, the bending radius as described above is taken into consideration. Therefore, sufficient measurement can be performed even if the smaller diameter perforated portion 23 is used.

  FIG. 5 shows the endoscope 1 inserted into the perforated part 23. As shown in FIG. 5, in the present invention, the endoscope 1 is inserted into the drilled portion 23 drilled by a drill, and the metal surface is formed by a spraying means (not shown) inserted through the working channel 6. By spraying a penetrating flaw detection agent used for detecting a defect or the like, the inside of the perforated part 23 is colored by being attached to the inner surface of the perforated part 23. Next, an image of the colored inner surface of the perforated part 23 is recorded while recording the insertion depth of the endoscope 1. By doing so, the crack position corresponding to the depth can be observed. At this time, as the crack position, the average value in the depth direction of the crack width obtained as described above can be used, and the shallow crack position or the deep crack position is used as a representative value depending on the purpose. Can be used.

As the above penetrant flaw detection agent, JIS
Penetration flaw detection agents that can be used in accordance with Z 2343 can be used, and specific examples include dyeing penetrants, fluorescent penetrants, binary dyeing penetrants, and binary fluorescent penetrants. it can. Further, the penetrant flaw detection agent is preferably sprayed without excess or deficiency, but a step of removing excess penetrant can be used in the present invention. Further, as the properties of the penetrant flaw detection agent, various forms such as a uniform solution, an emulsion, and a suspension can be adopted. For example, examples of the dye that can be used in the above-described penetrant flaw detector include oil red 5B, Sudan Red 462, Kayalite B, and Kayaset FG that is a fluorescent dye. Further, depending on the type of penetrant flaw detection agent, other processes such as drying and development can be used. When the fluorescent penetrating liquid is used, it is also possible to irradiate ultraviolet rays from the illumination optical fiber bundle 7b used as a light guide.

  The measurement of crack width will be further described with reference to FIG. In the present invention, the crack width is visually observed through the endoscope 1 by attaching a crack scale to the tip of a gripping member (not shown) inserted through the working channel 6 of the endoscope 1 and applying the crack scale to the cracked portion. Or later by image analysis.

  As for the crack length, the position of the crack 22 is measured by an image, and the scale is inserted into the crack 22 from the distal end portion of the endoscope 1 at a position corresponding to the crack position. When reaching the tip of the crack, the value of the crack depth can also be used.

  Further, the crack length is determined by forming a plurality of perforations 23 as shown in FIG. 5, observing the two-dimensional distribution and crack width of the crack 22, and measuring the two-dimensional distribution of the crack width. Thus, it can be obtained by extrapolation. An inspection method for this purpose is shown in FIG. FIG. 6A is a diagram in which the image density expressed using coloring or fluorescence intensity in a portion where the crack 22 does not exist in the perforated portion 23 is shown on the vertical axis, and the insertion depth of the endoscope 1 is shown on the horizontal axis. It is. FIG. 6B is a diagram showing the image density in the portion where the crack 22 exists in the perforated part 23, the vertical axis being the image density, and the horizontal axis being the insertion depth of the endoscope.

  As shown in FIG. 6A, the inner surface of the perforated portion 23 where no crack 22 exists is irradiated with illumination provided by the optical fiber bundle 7b to give a constant image density. However, if the crack 22 exists, the portion of the crack 22 is filled with the penetrant flaw detection agent or the developer when the development is separately performed, and the penetrant flaw detection agent remaining in the crack 22 is sucked up. As shown in FIG. 6B, the image density of the portion corresponding to the crack 22 increases.

  Further, the image density may decrease depending on the type of penetrant flaw detection agent used, the developing method, and the like. In the embodiment shown in FIG. 6 (b), it is shown that the color density of the crack portion is used, and the image density is increased. FIG. 6 (c) is a diagram showing the crack position and crack width with the horizontal axis representing the relative distance of each drill hole 23, with the above-described measurement repeated for the crack positions and crack widths for a plurality of drill holes 23. . The crack position is indicated by ◯, and the crack width is indicated by △. As the reference (0) of the relative position of the perforated part 23, for example, the center point of the crack observed on the concrete surface can be used.

  As shown in FIG. 6C, the crack is shown to have a large crack position, that is, a deeper position, according to the relative distance of the perforated portion 23. Moreover, the crack width becomes smaller as the crack becomes deeper. The crack length is obtained as the length up to the point where the plot of the crack position is extrapolated to the relative distance Y of the perforated part where the crack width becomes zero. Further, the value obtained by integrating the crack width with respect to the relative position of the perforated portion 23 gives the necessary volume of the filler used for filling the crack 22.

  By using such a plot, it is possible to estimate the depth and length of the crack even when the perforated portion 23 cannot be formed in accordance with the end portion of the crack. By analyzing the results obtained in this way, it is possible to estimate the crack depth with higher accuracy regardless of the formation position of the perforated part 23, and further calculate the amount of filler for repair. It becomes possible to do.

  The three-dimensional mapping of the deterioration state involves drilling with the above-mentioned small-diameter drill along a plurality of two-dimensional positions, obtaining information on crack width and crack depth for each drill, and performing three-dimensional mapping of cracks. Can be obtained.

(2) Poor filling of bean plate, cavity, and grout FIG. 7 shows bean plates and cavities as examples of defects that may occur in a concrete structure. A bean plate is a defect of concrete that becomes a bean plate due to separation of mortar and coarse aggregate due to defects in concrete placing method, tamping and formwork. Moreover, a cavity means the filling defect formed in concrete inside. If the bean sheet defect 24 and the cavity 25 shown in FIG. 7 are formed in concrete, the integrity of the concrete is locally lost, and as a result, a region having a lower strength than the surroundings is formed.

  FIG. 8 is a diagram showing that the inspection method of the present invention is applied to the defect shown in FIG. As a measuring method at this time, perforations 26 and 27 having a sufficient depth are formed by using a drilling means such as a drill in a site where the presence of the bean defect 24 or the cavity 25 of the concrete is confirmed by a sounding method or the like. To do. In FIG. 8, in the bean plate defect 24, it is shown that the perforations 26 are formed so as to penetrate the bean plate defect portion, but the perforations 27 are formed so as to penetrate the cavity 25. Not shown. However, the drilling depth can be changed as appropriate in consideration of the purpose of inspection, workability, and accuracy.

  When inspecting the bean plate defect 24 in the inspection method of the present invention, the endoscope 1 is inserted into the perforation 26 described above, and the insertion depth at that time is monitored. At this measured insertion depth, the bending portion 4 of the endoscope 1 is operated from the outside to change the angle, and images having different directions are taken into a computer, and the insertion depth and angle of the endoscope 1 are processed by image processing. From the above information, the state of the bean defect 24 can be reconstructed three-dimensionally.

  In measuring the diameter of the cavity 25, the length measuring jig 28 is inserted into the working channel 6 of the endoscope 1, and the angle of the bent portion 4 is changed so that the tip of the length measuring jig 28 is placed in the cavity 25. It is possible to measure by recording the insertion length of the length measuring jig 28 after observing the contact with the inner wall of the sword and using the endoscope 1. Further, by forming the measuring jig 28 from a wire-like member with a scale, the scale provided on the measuring jig 28 is directly read through the endoscope 1 and the diameter of the cavity 25 is measured. You can also Also in this case, a three-dimensional image of the cavity 25 can be obtained from the insertion depth of the endoscope 1 and the measurement result in the lateral direction by the measurement jig 28.

  FIG. 9 is a diagram showing an example in which the inspection method of the present invention is applied when grouting defects are observed. The grout 29 is used to fill a gap 32 between the concrete 30 and a steel material for prestressed concrete used for applying prestress to the concrete 30, that is, a PC steel material 31. If there is a defect, it will adversely affect the strength of the concrete structure, such as rust or improper fixing of the PC steel material 31.

  When the inspection method of the present invention is applied to such a filling failure of the grout 29, first, a site where the existence of the filling failure portion 33 of the grout is confirmed by the percussion method is drilled through the sheath 34. Perforate. The endoscope 1 is inserted into the perforated part 35, and the depth and the two-dimensional extent of the poorly filled part 33 are shown in the image monitor 17 shown in FIG. It is possible to perform three-dimensional mapping of the defective filling portion 32 by performing image analysis using a computer based on the recorded information.

(3) Tile and mortar float FIG. 10 is a diagram showing a case where the inspection method of the present invention is applied to defects such as tile and mortar float. The tile 36 is bonded to the concrete surface 37 with mortar, but the unity between the tile 36 and the concrete surface 37 is lost due to long-term use or construction failure, and as a result, a floating portion is interposed between the tile 36 and the concrete surface 37. A portion 38 will result. When the floating portion 38 is confirmed by a sounding method or the like, as shown in FIG. 8, a perforated portion 39 is formed in the floating portion 38 by a drilling means such as a drill, and the floating portion is formed by the same method as described above. Examine 38 spreads. The results obtained in this way are recorded in the computer 18 and can be subjected to three-dimensional mapping.

(4) Rusting of reinforcing bars Reinforcing bars are embedded in concrete to improve the tensile strength, but reinforcing bars may rust when used for a long time. When the reinforcing bars are rusted in this way, the integrity of the reinforcing bars and the concrete is lost, and the strength of the concrete is thus reduced. Therefore, the rusting of the reinforcing bars causes a serious strength defect in the concrete structure, so that a high-precision inspection is required.

  FIG. 11 is a diagram showing an example in which the inspection method of the present invention is applied to rusting of reinforcing bars. When the inspection method of the present invention is applied to the rusting of a reinforcing bar, first, after confirming the position of the reinforcing bar 40 by electromagnetic exploration, the drilled part 41 is formed by a drilling means such as a drill so as to reach the vicinity of the reinforcing bar 40 To do. When the reinforcing bars 40 embedded in the concrete 42 are rusted, an iron oxide layer 43 is formed, and the integrity between the concrete 42 and the reinforcing bars 40 is lost. In FIG. 11, it is shown that the piercing portion 41 is formed so as to reach the iron oxide layer 43 by the piercing means, but it is adjacent to the reinforcing bar 40 unless the reinforcing bar 40 is seriously damaged. It is also possible to form the perforated part 41 until the depth of the perforated part 41 exceeds the reinforcing bar 40 at a position that does not damage the reinforcing bar 40 in the vicinity of the position of the reinforcing bar 40 confirmed by the electric survey. It is also possible to provide it.

  In this case, if the space is formed by rusting, the optical inspection by the endoscope 1 is possible. Even if the space is not formed by rusting, the iron oxide layer 43 in the depth direction is used. It is possible to sample the thickness and iron oxide. Further, by forming a plurality of perforated portions 41 in the rusting site, it becomes possible to perform three-dimensional mapping based on the two-dimensional information and depth information of the rusting site, and to obtain more precise information. it can.

(5) Alkali-aggregate reaction, neutralization of concrete The inspection method of the present invention can also be applied to the inspection of alkali-aggregate reaction and neutralization in concrete. The alkali-aggregate reaction of concrete is a phenomenon in which aggregates abnormally expand due to alkali liberated during the hardening of concrete, thereby reducing the integrity of the concrete. This alkali-aggregate reaction can be carried out by attaching a penetrant flaw detection agent, an uranyl acetate aqueous solution or the like to concrete and visually observing with the endoscope 1. Moreover, about the neutralization of concrete, a phenolphthalein solution is made to adhere to concrete and visual observation is attained by discoloration of the phenolphthalein solution according to pH.

  FIG. 12 is a diagram showing an example when examining the alkali-aggregate reaction and neutralization. As an apparatus for measuring the alkali aggregate reaction and neutralization, an apparatus configuration using a spray apparatus similar to that shown in FIG. 5 can be used. In order to inspect the alkali-aggregate reaction and the neutralization of the concrete, the concrete is provided with a perforated part 44 by means of perforating means, the endoscope 1 is inserted into the perforated part 44, and the working channel 6 of the endoscope 1 is passed through. The medicine 45 described above is sprayed. After that, as described above, the insertion depth of the endoscope 1 and the coloring condition are associated with each other and recorded in the computer, so that information on the depth direction of alkali aggregate reaction and neutralization of concrete can be obtained. Obtainable. By measuring this multiple times by changing the two-dimensional position of the concrete, it becomes possible to perform a three-dimensional mapping of alkali aggregate reaction and concrete neutralization.

  FIG. 13 shows an inspection jig for performing the above-described various measurements more easily and with high accuracy. The inspection jig shown in FIG. 13 cuts the tip of a steel cylindrical pipe 46 horizontally, and the endoscope 1, crack scale 47 and drug injection tube 48 are inserted inside the pipe 46. ing. The pipe 46 may be made of steel or may be formed of a plastic having an appropriate strength. The diameter and length of the pipe 46 may be appropriately selected as necessary. In the embodiment described in the present invention, however, 9 mm. A crack scale operating rod 49 is connected to the crack scale 47, and the crack scale operating rod 49 is movably held by a holder (not shown) fixed to the inside in the radial direction of the pipe 46. The pipe 46 is pulled out from the opposite end and can be operated at hand. Further, the drug injection tube 48 has an end portion on the side inserted into the concrete facing outward in the radial direction so that the drug can be efficiently attached to the inner surface of the perforated portion. The opposite end of the pipe 46 is led out from the opposite end of the pipe 46 and connected to a medicine supply means (not shown).

  A mirror 50 movably attached to the cylindrical portion of the pipe 46 is disposed at the end of the pipe 46 on the side to be inserted into the concrete, and light irradiated through the light guide of the endoscope in the lateral direction. Is applied to the concrete surface, and reflection from the concrete surface can be sent to a micro imaging device (not shown). The mirror 50 is movable so that a concrete image can be appropriately observed by an operation at hand. An arrangement when viewing directly with the endoscope 1 is indicated by a virtual line. A scale 51 is formed on the outer surface of the pipe 46 so that the insertion depth can be directly observed.

FIG. 14 is a view showing in detail the crack scale 47 used in the inspection jig shown in FIG. Each of the crack scales 47 shown in FIG. 14 is printed on a transparent plastic. The crack scale 47 shown in FIG. 14 (a) is for measuring cracks in the direction perpendicular to the perforated part,
The crack scale 47 shown in FIG. 14B is used both vertically and horizontally, and the crack scale 47 shown in FIG. 14C has a protractor indicating the angle in the crack direction as a pudding. A crack scale operating rod 49 is attached to the crack scale 47 and can be operated at the hand operating section through the pipe 46.

  By using the inspection jig described above, the endoscope 1 can be protected by the pipe 46, so that the operation of the endoscope 1 becomes even easier. Furthermore, since the diameter of the pipe 46 can be made slightly smaller than the drilling means such as a drill, the distance from the wall surface of the drilled portion can be kept constant. Furthermore, the depth (position) of the deteriorated portion can be measured almost simultaneously while observing by directly reading the scale attached to the side surface of the metal tube so that the distance from the center of the image. Furthermore, since the distance from the endoscope tip to the mirror can be changed by hand operation, the observation range (magnification) can be arbitrarily changed. Moreover, since cracks and scales appear to be enlarged by measuring with an endoscope, it is possible to perform an inspection with the same system when magnifying and observing with a magnifying glass or the like. In addition, by holding the crack scale on the pipe, it is possible to easily and accurately match the crack scale to a crack within a narrow observation range of 10 mm to 15 mm.

  FIG. 15 is a view showing a measurement jig that can be used to measure deterioration such as a cavity formed in a concrete structure, a grout filling state, and the like. The measurement jig 52 shown in FIG. 15 has a laser light source 53 attached to the distal end portion of the endoscope 1 and is configured to irradiate laser light 54 from the distal end portion of the endoscope. The laser beam 54 reflected by the concrete surface 55 is incident on the optical fiber of the endoscope 1 and propagates to a micro imaging device (not shown), and the spot diameter formed on the concrete surface 55 is monitored by a monitor, CCD or the like. Observed. The laser beam 54 is emitted from the distal end portion of the endoscope 1 to a cavity formed in the concrete or a grout poorly filled portion. At this time, the laser beam 54 has good parallelism and does not substantially spread at a distance from the distal end of the endoscope 1 to the concrete surface 55.

  The measuring jig 52 shown in FIG. 15A uses the above-mentioned characteristics of the laser beam 54 and uses the spot diameter of the laser beam as a scale. The endoscope 1 has a proportional relationship between the distance to the specimen and the observation magnification. The larger the distance, the smaller the magnification (looks smaller), and the smaller the distance, the larger the magnification. Accordingly, the smaller the spot diameter irradiated on the concrete surface 55 is observed by a monitor or the like, the larger the distance is, and the larger the spot diameter is observed, the smaller the distance is.

  FIG. 15B is a diagram schematically showing changes in the spot diameter observed by a monitor or the like when the concrete surface 54 is located at the positions A, B, and C shown in FIG. is there. As described above, as the distance from the distal end portion of the endoscope 1 increases, the spot diameter decreases. By measuring this relationship in advance, quantitative measurement can be performed. By using the measuring jig shown in FIG. 15, it is possible to observe, inspect and judge concrete deterioration by one worker using a small and inexpensive measuring jig in the field. Further, by performing such measurement over 360 °, it becomes possible to three-dimensionally map the filling failure of cavities and grout. The measurement jig using the laser beam mentioned above can measure without contact with the concrete surface, and the laser light source and the system can be made compact, so that the diameter of the drilled portion can be kept small. Can do.

  Further, the laser light source 53 to be used is not necessarily one, but a plurality of spots separated by a certain distance are given to the concrete surface 55, and the distance between these spots is used as described above. The distance to the concrete surface 55 can also be measured in consideration of the observation magnification.

  After applying the above-described inspection method of the present invention to a concrete structure, the perforated portion is filled with concrete, grout or the like to repair the concrete structure.

  The present invention has been described with reference to the drawings. However, the present invention is not limited to the embodiments shown in the drawings, and the types of defects, types of endoscopes, types of image transmission means, drugs It will be understood that any known image processing means can be used.

Schematic which shows the endoscope used for this invention. Schematic which showed the cross section of the bending part of the endoscope used for this invention. 1 is a front view of a micro imaging apparatus used in the present invention. The figure which showed the concrete structure which provides this invention. The figure which showed the crack position measurement of this invention. The figure which showed the Example of the measuring method of the crack position of this invention. The figure which showed the bean plate defect and cavity which apply this invention. The figure which showed the Example of this invention applied to a bean board defect and a cavity. The figure which showed the Example of this invention applied to the filling defect of grout. The figure which showed the Example of this invention applied to the floating of a tile and mortar. The figure which showed the Example of this invention applied to the rusting of a reinforcing bar. The figure which showed the Example of this invention with respect to alkali aggregate reaction and neutralization. Schematic which showed the measuring jig of this invention. The figure which showed the crack scale used by this invention. The figure which showed the example of a change of the measurement jig | tool used by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Endoscope 2 ... Optical system 3 ... Inspection means 4 ... Bending part 5 ... Swing operation part 6 ... Working channel 7 ... Optical fiber bundle 7a ... Optical fiber bundle 7b for measurement ... Optical fiber bundle 8 for illumination ... Bundling member 9 ... Insertion Part 10 ... Swing tip metal 11 ... Fiber sheath 12 ... Optical fiber 13 ... Objective lens 14 ... Swing pull wire 15 ... Micro imaging device 16 ... Tip optical system 17 ... Image monitor 18 ... Computer 19 ... Keyboard 20 ... Video camera DESCRIPTION OF SYMBOLS 21 ... Illuminating device 22 ... Crack 23 ... Perforated part 23a ... Perforated part 24 ... Bean plate defect 25 ... Cavity 26 ... Perforated part 27 ... Perforated part 28 ... Measuring jig 29 ... Grout 30 ... Concrete 31 ... PC steel 32 ... Gap 33 ... Poor filling part 34 ... sheath 35 ... perforated part 36 ... tile 37 ... concrete surface 38 ... floating part 39 Perforated part 40 ... reinforcing bar 41 ... perforated part 42 ... concrete 43 ... iron oxide layer 44 ... perforated part 45 ... drug solution 46 ... pipe 47 ... crack scale 48 ... drug injection tube 49 ... crack scale operating rod 50 ... mirror 51 ... scale 52 ... Measurement jig 53 ... Laser light source 54 ... Laser beam 55 ... Concrete surface

Claims (2)

Forming a perforated portion in a concrete structure;
Inserting an endoscope into the perforated part;
Inserting an endoscope having a bendable tip into the perforated part;
Bending the endoscope, and observing bean plate defects in the depth direction of the concrete, cavities, poor filling, floating of tiles and mortar, or rusting through the endoscope;
A measuring jig is inserted through the endoscope, and the three-dimensional image is obtained by capturing the image of the bean plate defect, cavity, filling defect, tile or mortar floating, or rusting into a computer in a three-dimensional manner. A method for inspecting a concrete structure, comprising: The inspection method according to claim 1, further comprising a step of attaching a drug from the endoscope to the inside of the perforated part after the insertion step.

Images