JP2002156347A - Structure inspection device, carrier car for inspecting structure, and structure inspection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly precisely detect the presence and the depth of a defect in an inner structure. SOLUTION: Heating time is expressed by t, the first place and the first time of a first photographing by a photographing part 9 are expressed by x and T11, a second place and a second time of a second photographing by the photographing part 9 are expressed by x and T12, and the first place and the second place are set the same. A first image of the first photographing is expressed by F11 (x, z, T11), a second image is expressed by F12 (x, z, T12), and the depth z of the defect is detected by an image-processing part 16 by the simultaneous images between the first image F11 (x, z, T11) and F12 (x, z, T12). The defect depth z, detected by this method, can be detected with high precision by the calculation. When the structure is concrete, it is preferable that the heat ray wavelength region be within a range of 1 μm-50 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a structure inspection apparatus,
In addition, the present invention relates to a structure inspection method and, more particularly, to a structure inspection device and a structure inspection method for detecting an internal defect of a concrete structure such as a tunnel, viaduct, condominium, or mortar structure.

[0002]

2. Description of the Related Art The collapse of a concrete structure such as a tunnel has recently become a social problem, and measures against it are urgently required. At present, such prediction and inspection of deterioration of concrete structures mainly rely on hammering inspection methods performed by workers using a hammer or the like.
It is difficult to quantitatively evaluate deterioration and defects, and the evaluation differs depending on the worker who inspects.It depends on the special ability of the person instead of the sensory inspection such as hammering inspection, which is expensive and time-consuming and expensive. As a non-contact method, a non-contact inspection method using an infrared camera is known as disclosed in Japanese Patent Application Laid-Open No. 5-45314. Further, using a plurality of light sources for irradiating light to the concrete structure, an infrared camera and a visible camera for photographing the surface of the structure illuminated by those light sources, and a photographing vehicle equipped with the light source and the camera,
There is also known a method of inspecting an exfoliated portion which is an internal gap based on a temperature difference between inner wall surfaces.

FIG. 10 shows such a non-contact inspection apparatus utilizing infrared rays and an inspection method. The inspection device includes a light source 10 for irradiating light to the surface of the concrete structure 101.
2, a power supply 103 thereof, a visible camera 104 for photographing the surface of the concrete structure 101, and an infrared camera 10
5 and image storage devices 106 and 107 for storing images taken by these cameras 104 and 105, respectively.
And These devices are mounted on a photographing vehicle (not shown) and move along the surface of the concrete together with the photographing vehicle. Based on the two images stored in the image storage devices 106 and 107, a concrete crack or a defect inside the concrete is detected and evaluated.

[0004] The non-contact inspection technique using such an infrared camera can detect only a defect in a surface layer, and the obtained image has low definition and poor evaluation accuracy.

It is required that the presence or absence of an internal defect can be evaluated with high evaluation accuracy.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a structure inspection apparatus, a structure inspection carrier, and a structure inspection method capable of evaluating the presence or absence of an internal defect with high evaluation accuracy. Is to do.

[0007]

Means for solving the problem are described as follows. The technical items appearing in the expression are appended with numbers, symbols, and the like in parentheses (). The numbers, symbols, and the like are technical items that constitute at least one embodiment or a plurality of the embodiments of the present invention, in particular, the embodiments or the examples. Corresponds to the reference numerals, reference symbols, and the like assigned to the technical matters expressed in the drawings corresponding to the above. Such reference numbers and reference symbols clarify the correspondence and bridging between the technical matters described in the claims and the technical matters of the embodiments or examples. Such correspondence / bridge does not mean that the technical matters described in the claims are interpreted as being limited to the technical matters of the embodiments or the examples.

A structure inspection apparatus according to the present invention takes an image of a thermal light source (6) and a structure irradiated with heat rays in the heat ray wavelength region of the thermal light source (6) and subjected to heating in the heat ray wavelength region. An imaging unit (4, in particular, 9); and an image processing unit (16) that detects the presence of a defect inside the structure (C) based on an image generated by the imaging unit (9). 9)
Captures the surface of the structure (C) at a time delayed by the time T from the heating time. During the delay time T, the heat on the surface of the structure irradiated with the heat rays is diffused and transmitted to the inside, and a temperature distribution reflecting the internal defect appears on the surface of the structure. The temperature distribution of such a structure surface is photographed by the photographing unit (9). The temperature distribution pattern is known in advance in relation to the time T, so that not only the presence of the internal defect but also the depth of the internal defect can be grasped to some extent. The heat of the surface given by the heat ray easily penetrates into the inside, and its permeability depends on the correspondence between the heat ray wavelength region and the structural material. In particular, heat on the concrete surface given by infrared rays easily and efficiently penetrates into the inside of the concrete structure (C). In this case, the thermal light source (6) is an infrared light emitting source, and the imaging unit (9) is an infrared camera having high sensitivity to infrared light.

The heating time is represented by t, the first location and the first time of the first photographing of the photographing section (9) are represented by x and T11,
The second location and the second time of the second imaging of the imaging unit (9) are x and T
12, the first location and the second location are the same,
The first image of the photograph is represented by F11 (x, z, T11),
The second image is represented by F12 (x, z, T12), and the depth z of the defect is obtained from the simultaneous image of the first image F11 (x, z, T11) and the second image F12 (x, z, T12). Processing unit (1
6). Defect depth z for such detection
Can be detected with high accuracy by calculation. When the structure (C) is concrete, the heat ray wavelength range is 1 μm to 50 μm.
It is preferably in the range of μm.

The photographing section (9) includes a first camera (9) having an appropriate sensitivity in a first wavelength region included in the heat ray wavelength region,
A second camera (11) having an appropriate sensitivity in a second wavelength region having a wavelength shorter than the first wavelength region, wherein the heating time is t
Where the location and time of shooting by the first camera (9) are represented by x and T1, the location and time of shooting by the second camera (11) are represented by x and T2, and the first camera (9) The shooting location of the second camera (11) is the same as the shooting location of the second camera (11).
The photographing time of the camera (9) and the photographing time of the second camera (11) are the same, and the photographed image of the first camera (9) is represented by F1 (x, T1), and the second camera ( The image captured in 11) is represented by F2 (x, T1), and the image F1 (x, T1)
T1) and the image F2 (x, T1), the presence of a defect inside the structure (C) is detected by the image processing unit (16). The image of the second camera (11) has an image component that does not depend on the heat distribution of the morphology (such as cracks) of the structure surface, and this image component is removed from the image of the first camera (9), that is, The images are synthesized, and the synthesized image after the image synthesis is
Reflect the thermal distribution of the structure surface with higher accuracy.

A transport vehicle for structural inspection according to the present invention is a transport vehicle for structural inspection which carries such a structural inspection device and transports the structural inspection device, and has a structural surface of a structure (C). (28) running along the vehicle, a first moving body (26) supported by the wheels (28), and a first moving body (26)
A second moving body (25) supported by the first moving body (26) and moving with respect to the first moving body (26), and a part (16) of the photographing unit (4).
Is mounted on the first mobile unit (26), and the other part (9, 11) of the imaging unit (4) is mounted on the second mobile unit (25). The structure inspection carrier can move along the surface of the structure and travel twice on the same travel path. The first camera (9) and the second camera (11) are mounted on the same second moving body (25) and can photograph the same place. A third moving body (36) supported by the second moving body and moving with respect to the second moving body (25) is further added. In this case, the first camera and the second camera
It is mounted on the same third moving body (36). Preferably, the wheels are guided and run on a track (48).

The method for inspecting a structure according to the present invention includes irradiating a surface of the structure (C) with a heat ray at a time t, photographing the surface in a long wavelength region included in the heat ray at a time t + T at a long wavelength. Detecting the presence of an internal defect in the structure (C) based on an image obtained by long-wavelength imaging. The position of the surface is represented by a function of time t.

The presence and depth of an internal defect in the structure (C) based on two images obtained by taking a long wavelength image of the surface at a time t + T + ΔT in a long wavelength region and taking a long wavelength image at a time t + T and a time t + T + ΔT. Is detected. The surface is set at time t in a short wavelength region shorter than the wavelength in the long wavelength region.
+ T to shoot a short wavelength, and to detect the presence of the internal defect of the structure (C) with high accuracy based on the image obtained by the long wavelength shooting and the image obtained by the short wavelength shooting. Is further added.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Corresponding to the drawings, a structural inspection apparatus according to the present invention is provided with a defect inspection device together with a mobile inspection vehicle. As shown in FIG. 1, a defect inspection device 2 is mounted on the mobile inspection vehicle 1. Mobile inspection vehicle 1
Is a transport vehicle that transports the defect inspection device 2 such as a rail car, a free rail car, and a manual push cart.

The defect inspection device 2 includes a photographing unit 3 and an image processing unit 4
And The photographing unit 3 and the image processing unit 4 include a control unit 5
Is controlled by The imaging unit 3 particularly includes a heating source 6 and a camera 7. The heating source 6 is a heating light source,
In particular, a light source that emits infrared light in an appropriate wavelength region of 1 μm to 50 μm is preferable. Between the heating source 6 and the control unit 5, a power source 8 for emitting infrared light in a flash manner is specially provided.

The camera 7 includes an infrared camera 9 in which a photoelectric element sensitive to a specific infrared wavelength is formed on the imaging surface, and a high sensitivity camera 11 in which a photoelectric element sensitive to visible light is formed on the imaging surface. In. The core of the imaging unit 3 is, in particular,
An infrared camera 9. The high-sensitivity camera 11 is high-sensitivity and can output a clear image in a place where the amount of natural light is small, such as in a tunnel or on the lower surface of a bridge girder. The heating source 6 is a heat ray source that emits heat rays. The heat rays include the above-described light in the infrared region of 1 μm to 50 μm and light in the visible light wavelength region having a shorter wavelength. I have. The infrared rays do not warm the air facing the concrete but directly hit the concrete and are well absorbed by the concrete, and the heat received by the concrete surface by the infrared rays penetrates well into the interior. Conversely, the concrete surface radiates heat received from infrared rays well as infrared rays.

A first image captured by the infrared camera 9 or a second image output 12 corresponding to the first image is input to a first image generation (processing) unit 13. The second image captured by the high-sensitivity camera 11 or the corresponding second image output 14 is input to a second image generation (processing) unit 15. First image processor 13
The first image output 12 subjected to the image processing by the second image output 14 and the second image output 14 subjected to the image processing by the second image processor 15 are respectively subjected to image processing by the first image processor 13 and the second image processor 15. Upon receiving the processing, the image synthesizing (comparing) unit 16
And the image is synthesized by the image synthesizer 16. Image synthesis can compare both images, and in particular, can compare the shading of both images. The image synthesizer 16 compares the two images with a depth detector having a detection capability of detecting a depth of a defect described later of the structure, or a detection element included in such a depth detector. is there.

FIG. 2 shows the details of the mobile inspection vehicle 1. The image processing unit 4, the power supply 8, the first image processor 13, and the second
The image processor 15 and the image synthesizer 16 are installed on the bed 17 of the mobile inspection vehicle 1. A support table 19 is supported by the load table 17 via an arm 18 having a tip that can be raised and lowered and moved up and down at a constant inclination angle. A movable table 21 that can move in a two-dimensional direction is supported by the support table 19. The heating source 6, the infrared camera 9, and the high-sensitivity camera 11 are supported on the carrier 17 via the support 19 and the movable platform 21. In such a supporting state, the infrared irradiation angle of the heating source 6, the imaging angle of the infrared camera 9 (first optical axis direction), and the imaging angle of the high sensitivity camera 11 (second optical axis direction) are respectively constant. Is maintained.

The heating source 6, which emits infrared rays, irradiates the lower surface fixed area of the concrete structure C forming the ceiling or the floor slab of the bridge. The infrared camera 9 captures an image of a partial fixed area in the fixed area on the lower surface. The high-sensitivity camera 11 captures an image of a partial quantitative area that is substantially the same as the partial quantitative area.

As shown in FIG. 2, the arm 18 is raised and lowered, and the support base 19 is set at an appropriate height position with respect to the lower surface of the concrete structure C. If the reciprocating traveling path of the mobile inspection vehicle 1 is the same, the moving table 21 is displaced in a direction orthogonal to the traveling path to move the photographing path on the lower surface of the concrete structure C. The infrared rays generated by the heating source 6 are
The concrete wall can be heated and raised to a predetermined temperature in a short time with high efficiency.

If the infrared irradiation heating time for each location x is represented by t, the time t + T is separated from the time by a time interval T.
Then, the same place is photographed by the infrared camera 9 and the high sensitivity camera 11. The first shot taken by the infrared camera 9 at time t + T
The image is represented by F1 (x, t + T), and the second image taken by the high-sensitivity camera 11 at time t + T is F2 (x, t + T)
It is represented by Where x is a function of time t. Shooting the first image and the second image at the same time ensures that the first image and the second image are at the same position with high accuracy.

The heat of the concrete surface layer heated by the infrared irradiation gradually diffuses into the concrete, and the heat inside the concrete heated by such diffused heat is transferred to the concrete surface layer and the side opposite to the surface layer. The concrete diffuses to the outside of the concrete, and the inside of the concrete cools down uniformly. If the inside of the concrete is homogeneous, the cooling is uniform in place, but if there is a defect (a minute space such as a hole or a crack) inside the concrete and the inside is not homogeneous, the cooling of the minute space The air and steam inside impair the uniformity of the heat conductivity and cut off the heat transfer.
Such local interruption of heat conduction causes a difference in the temperature drop of the concrete surface between the defect and its surroundings,
The temperature on the concrete surface will not be uniform. In general, the temperature of the concrete surface closer to the local defect location becomes higher, and the temperature of the concrete surface farther to the local defect location becomes lower. Such a temperature drop is correlated with the time T described above. Such an optimal time interval T is set theoretically or empirically.

The temperature difference is emphasized in the first image F 1 (x, t + T) generated by the infrared camera 9.
In the first image, the hotter parts are whiter. Therefore, the position of the internal defect can be detected from the density of the first image (black and white). The color intensity of the first image has a correlation with the temperature of the concrete and the inside, and changes in response to the temperature decrease. Therefore, the depth of a defect can be known by sequentially photographing the same portion at different time intervals after heating to a predetermined temperature. If two time intervals are represented by T1 and T2, the first image is F1 (x, z, t +
T1) and F1 (x, z, t + T2). F
1 (x, z, t + T1) and F1 (x, z, t + T2) are simultaneously established, and the difference indicates the depth z of the defect. The size of the defect can be known from the distribution of shading. If a large white area exists in the image, the internal defect is large. If the difference in density is strong, the depth of the defect is large.
From time t to time T1 or time T2, the mobile inspection vehicle 1 does not need to be stopped.

Two second images F2 generated by the high-sensitivity camera 11 for photographing the same area at the same time as the photographing of the first image
(X, T1) and F2 (x, T2) are sensitive and accurate copies of the concrete surface. The second image F2 (x,
T1) is in principle identical to the second image F2 (x, T2). The second image F2 accurately represents the presence and shape of a defect or crack on the concrete surface. The first image F1 and the second image F2 are synthesized by the image synthesizer 16. Since the composite image F3 clearly indicates the defect on the concrete surface together with the presence of the internal defect, the presence and depth of the internal defect are examined with reference to the presence of the surface defect, and the detection accuracy of the internal defect is improved.

FIG. 3 shows another embodiment of the structure inspection apparatus according to the present invention. The present embodiment lies in a modification of a transport vehicle that transports the defect inspection device 2. The concrete side C ′ is a side wall having two vertical surfaces and a top surface. One of the two vertical surfaces is the defect detection target surface 22. The moving body 23 that is self-propelled while sandwiching the two vertical surfaces of its side wall is the moving body 2.
4 and a vertical rod 25. The moving main body 24 is formed of a vertical portion 26 on both sides and a horizontal portion 27 connecting upper end portions of the vertical portions 26 on both sides in the horizontal direction. A plurality of rolling wheels 28 are interposed between the inner surfaces of the vertical portions 26 on both sides and both vertical surfaces of the concrete structure C ′, and are rotatably supported by the moving body 24.

A pair of support portions 29 are provided, which are fixed to the vertical portions 26 on both sides and protrude in the horizontal direction. The vertical rod 25 penetrates the support portion 29 in the vertical direction, and
It is fixed to. The mounting part 31 is guided by the vertical rod 25 and supported by the vertical rod 25 so as to be vertically movable. The mounting portion 31 supports the heating source 6, the infrared camera 9, and the high-sensitivity camera 11. As shown in FIG. 4, the infrared camera 9 and the high-sensitivity camera 11 are attached to the mounting portion 31 via an arm 32 projecting horizontally from the mounting portion 31.
It is supported by. Image processing unit 4 and first image processor 13
The second image processor 15 and the image synthesizer 16 are supported on the upper surface of the horizontal portion 27. The illustration of the driving device of the moving main body 24 is omitted.

The heating source 6 irradiates one vertical surface of the concrete structure C ′ with infrared rays to heat the wall surface thereof, and the infrared camera 9 and the high-sensitivity camera 11 transmit the first image F1 described above.
(X, z, T1), F1 (x, z, T2) and a second image F2 (x, z, T) are generated. By combining these images, the size and the depth z of the defect inside the concrete structure C ′ are detected.

FIG. 5 shows still another embodiment of the structure inspection apparatus according to the present invention. The present embodiment lies in another modification of the transport vehicle that transports the defect inspection device 2. The concrete bottom portion C ′ of the slab overhang of the bridge is the same as the concrete structure C ′ of the above-described embodiment, is a side wall having a vertical surface and a top surface, and further has a bottom surface. I have. The bottom surface is the defect detection target surface 33. The moving main body 24 and the support portion 29 are the same as those of the above-described embodiment. The vertical rod 25 of the above-described embodiment is modified to a vertical rod 25 'with a lower end extending downward.

At the lower end of the vertical rod 25 ', a vertical rod 2
First support table 34 guided by 5 'and supported so as to be able to move up and down
Is provided. A first orthogonal arm 35 that is supported by the first support base 34 and extends in a direction perpendicular to the traveling direction of the moving body 24 and in the horizontal direction is provided. The first orthogonal arm 35 can be supported by the first support 34 so as to be movable in the horizontal direction. The second support base 36 is movably supported by the first orthogonal arm 35. As shown in FIG. 6, there is further provided a second orthogonal direction arm 37 which is supported by the second support base 36 and extends in the traveling direction of the movable body 24 at right angles to the first orthogonal direction arm 35. The heating source 6 is supported on a second support base 36. The infrared camera 9 and the high-sensitivity camera 11 are supported by the tip of the second orthogonal arm 37. As clearly shown in FIG. 6, the heating source 6 is
4. Infrared camera 9 and high-sensitivity camera 11
And is arranged at a position preceding the above.

The defect status inside the defect detection target surface 33 heated by the preceding heating source 6 is detected by the infrared camera 9 and the high-sensitivity camera 11 that follow. The infrared camera 9 and the high sensitivity camera 11 are connected to the first image F1 described above.
(X, z, T1), F1 (x, z, T2) and a second image F2 (x, z, T) are generated. By combining these images, the size and the depth z of the defect inside the concrete structure C ′ are detected.

FIGS. 7 and 8 show still another embodiment of the structure inspection apparatus according to the present invention. The present embodiment lies in still another modification of the transport vehicle that transports the defect inspection device 2. The moving body 24 ', which is the main body of the transport vehicle, runs across a steel column 38 rising from the concrete bottom C "of the slab. The steel column 38 is composed of a horizontal bar 39 and a vertical bar 41, The plurality of rolling wheels 28 'of 24' roll on the cylindrical surface of the horizontal bar 39. The support portion 29 is moved by the moving main body 2.
4 ′, the vertical rod 2
The point where 5 'is provided is the same as the above-described embodiment. The mutual arrangement of the heating source 6, the infrared camera 9, and the high-sensitivity camera 11 is the same as in the above-described embodiment.

FIG. 9 shows still another embodiment of the structure inspection apparatus according to the present invention. The present embodiment lies in still another modification of the transport vehicle that transports the defect inspection device 2. The concrete bottom C ′ or C ″ to be inspected is the same as the floor slab bottom C ′ of the above-described embodiment. A plurality of steel girders 42 are fixed to the lower surface of the floor of the concrete bottom C ′. The partial moving body 43 is formed of a traveling girder 44 and an arm 45. An upper surface forming portion 46 at the lower end of the arm 45 and the steel girder 42.
And a traveling wheel mechanism 47 is interposed between them. Running girder 44
In addition, a guide rail 48 is provided in the horizontal direction. The traveling body 51 is supported by the traveling girder 44 so as to be able to traverse freely via a plurality of wheels 49 which sandwich the guide rail 48 from the upper and lower surfaces. The heating source 6, the infrared camera 9, and the high sensitivity camera 11
It is mounted on the traveling body 51.

The traveling direction of the traveling girder 44 is orthogonal to the traveling direction of the traveling body 51. The heating source 6, the infrared camera 9 and the high sensitivity camera 11 move the lower surface of the concrete structure C ′ to 2
It is possible to scan in a three-dimensional manner, and it is possible to more safely inspect the lower surface of the concrete floor which is difficult for a person to access.

The traveling device found in the plural embodiments is
It has a running body that runs automatically or semi-automatically, and moves one-dimensionally or two-dimensionally to determine the presence and size of internal defects in concrete in narrow and dangerous areas where it is difficult for people to enter. It can be detected safely and with high accuracy.

An area to be photographed by the infrared camera 11 is irradiated with infrared light having an appropriate wavelength from the infrared light source 6. The infrared light emitted by the infrared light source 6 exists in a wavelength range of 1 μm to 50 μm. The infrared camera 11 moves integrally at a speed corresponding to the traveling speed of the inspection vehicle or at the same speed. The effective detection wavelength of the infrared camera is 8 μm to 13 μm
The detection infrared wavelength region is included in the irradiation infrared wavelength region. Irradiation infrared rays are emitted from the infrared light source 6 to the wall surface. The infrared rays radiated on the wall
While heating the concrete surface, it penetrates into the concrete and raises the overall temperature of the concrete. When there is a gap such as peeling in the concrete, the air blocks heat conduction, and when there is peeling inside, the temperature of the peeling existing part in the concrete rises higher than that of a healthy part having no gap. When this phenomenon is properly detected by the infrared camera 11, it is important to select a detection wavelength region of the infrared camera. Generally, an infrared camera has a detection wavelength of 3 μm.
The area is roughly classified into two areas, namely, an m-5 μm area and an 8-12 μm area. When the detection is performed at a wavelength in the range of 3 μm to 5 μm, only the temperature of the concrete surface can be properly detected because the detection wavelength is short.

On the other hand, when detection is performed at a wavelength in the range of 8 μm to 12 μm, since the detection wavelength is long, not only radiation from the concrete surface but also radiation from the inside of the concrete is indirectly detected. The temperature can be detected more appropriately. Therefore, an infrared camera used as a detector for detecting peeling existing inside concrete has a detection wavelength of 8 μm to 13 μm,
Alternatively, a wavelength region close to the detection wavelength, for example, 7 μm to
It is indispensable in the current technology to use an infrared camera having a region of 16 μm or the like.

By detecting with an infrared camera whose sensitivity is appropriate for such a wavelength region, a portion having peeling or voids in concrete can clearly identify a peeling portion by a temperature difference from a surrounding healthy portion. It is possible to
Non-destructive inspection of internal gaps and voids that cannot be seen by the operator's eyes is possible. Here, by irradiating the structure with infrared light, the wavelength of the irradiated light is longer than when a light source such as a Xe flash lamp used in the conventional method is used, so that the surface of the structure is efficiently heated. can do.

When the position where the peeling or the void exists in the concrete is shallow, the temperature difference between the sound part and the defect existing part detected by the infrared camera 11 becomes large, and the position where the peeling or the void exists is deep. In this case, the temperature difference between the sound part and the defective part detected by the infrared camera 11 becomes small. Therefore, based on the temperature difference between the healthy part and the defective part, it is possible to detect the depth of the defect such as peeling or void inside the concrete structure by calculation.

As described above, compared with the conventional tapping sound inspection method, it is possible to perform a non-contact and high-speed inspection, perform a quantitative evaluation without relying on human intuition, and perform an inspection as compared with the conventional tapping sound inspection method. Cost can be significantly reduced. In the case of the conventional non-contact inspection method, only about 5 mm can be detected. However, according to the present invention, the inspection can be performed up to a maximum depth of 60 mm in the above embodiment. In a later embodiment, in comparison with the conventional non-contact inspection method, in the detected infrared image, by quantitatively evaluating the temperature difference between the sound part and the defect existing part, the depth direction, which was difficult in the related art, Inspection with high resolution has become possible.

An image obtained by a camera using visible light can be used as reference data for judging abnormalities on the surface of the inspection object. The present invention is not limited to tunnels, and can exert its effects also in inspection of concrete structures and mortar structures such as viaducts and condominiums.

[0041]

The structure inspection apparatus, structure inspection transport vehicle, and structure inspection method according to the present invention can reliably detect the presence of an internal defect. In particular, its size and depth can be quantitatively detected simultaneously with high accuracy.

[Brief description of the drawings]

FIG. 1 is a front sectional view with a circuit block showing a structure inspection apparatus according to the present invention.

FIG. 2 is a front sectional view showing details of an embodiment of a structure inspection method according to the present invention.

FIG. 3 is a front view showing a structure inspection target;

FIG. 4 is a side view of FIG. 3;

FIG. 5 is a front view showing another structural object to be inspected.

FIG. 6 is a side view of FIG. 5;

FIG. 7 is a front view showing still another structure inspection object.

FIG. 8 is a side view of FIG. 7;

FIG. 9 is a front view showing still another structure inspection target.

FIG. 10 is a front view showing a known structure inspection apparatus.

[Explanation of symbols]

 6 ... Thermal light source 4 or 9 ... Photographing unit 9 ... First camera 11 ... Second camera 16 ... Image processing unit 26 ... First moving body 25 ... Second moving body 28 ... Wheel 36 ... Third moving body 48 ... Orbit C: Structure

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA25 AA49 AA51 BB02 CC14 DD03 FF04 FF42 GG01 GG21 JJ03 JJ05 JJ26 QQ21 QQ24 QQ25 QQ32 2G040 AA05 BA01 BA16 CA05 CA12 CA23 DA06 EA06

Claims (11)

[Claims] 1. A thermal light source; a photographing unit for photographing a structure irradiated with heat rays in a heat ray wavelength region of the thermal light source to perform heating in the heat ray wavelength region; and an image generated by the photographing unit. An image processing unit for detecting the presence of a defect inside the structure based on the structure, wherein the photographing unit photographs a surface of the structure at a time delayed by a time T from a time of the heating. apparatus. 2. The time of the heating is represented by t, the first place of the first photographing of the photographing unit and the first time are represented by x and T11, and the second place of the second photographing of the photographing unit. The second time is represented by x and T12, the first location and the second location are the same, and the first image of the first shooting is F11 (x, z, T1).
1), and the second image is F12 (x, z, T1
2), and the depth z of the defect is a first image F11
(X, z, T11) and the second image F12 (x, z, T1)
The structure inspection apparatus according to claim 1, wherein the structure is detected by the image processing unit from the combination of 2). 3. The imaging section has a first camera having an appropriate sensitivity in a first wavelength region included in the heat ray wavelength region, and an appropriate sensitivity in a second wavelength region having a shorter wavelength than the first wavelength region. A second camera, wherein the heating time is represented by t, the shooting location and time of the first camera are represented by x and T1, and the shooting location and time of the second camera are represented by x and T2. Where the shooting location of the first camera and the shooting location of the second camera are the same, the shooting time of the first camera and the shooting time of the second camera are the same, An image captured by the first camera is represented by F1 (x, T1), an image captured by the second camera is represented by F2 (x, T1), and the image F1 (x, T1) and the image F2 ( x, T1)
The structure inspection apparatus according to claim 1, wherein the presence of a defect inside the structure is detected by the image processing unit based on the following. 4. The heat ray wavelength range is an infrared range of 1 μm to 50 μm, and the structure is formed of concrete.
3. Structure inspection device. 5. A transport vehicle for a structure inspection which carries the structure inspection device by mounting the structure inspection device according to claim 1, wherein a wheel running along a structural surface of the structure, A first moving body supported by the wheels; and a second moving body supported by the first moving body and moving with respect to the first moving body, wherein a part of the photographing unit performs the first movement. The structure inspection carrier is mounted on a body, and another part of the photographing unit is mounted on the second movable body. 6. A structure inspection transport vehicle carrying the structure inspection device according to claim 1, wherein the vehicle travels along a structural surface of the structure, A first moving body supported by the wheel, a second moving body supported by the first moving body and moving with respect to the first moving body, and a second moving body supported by the second moving body. A third moving body that moves with respect to the first moving body, and a part of the photographing unit is mounted on the first moving body, and another part of the photographing unit is mounted on the third moving body. Carriage for object inspection. 7. The structure inspection transport vehicle according to claim 5, wherein the wheels travel while being guided by a track. 8. Irradiating the surface of the structure with a heat ray at time t, the surface is irradiated at a time t + T in a long wavelength region included in the heat ray.
Detecting the presence of an internal defect of the structure based on an image obtained by performing the long-wavelength imaging, wherein the position of the surface is represented by a function of the time t. And a structure inspection method including: 9. The time t + T + ΔT of the surface in a long wavelength region
The structure further comprising: detecting presence and depth of an internal defect of the structure based on two images obtained by performing the long-wavelength imaging at the time t + T and the time t + T + ΔT. Inspection methods. 10. A short wavelength image of the surface at a time t + T in a short wavelength region shorter than a wavelength of the long wavelength region, and an image obtained by the long wavelength image and the short wavelength image are obtained. And detecting the presence of the internal defect of the structure with high accuracy based on the obtained image. 11. A method for inspecting a structure, wherein long-wavelength imaging is performed by an infrared camera, and said short-wavelength imaging is performed by a visible light camera.