Brace deformation detection method and brace deformation detection system

Abstract

To provide a brace deformation detection method and a brace deformation detection system that can easily detect the deformation state of a brace arranged inside an exterior wall.SOLUTION: A brace deformation detection method for detecting deformation of a brace 26 reinforcing an exterior wall 20 of a building includes: a frequency setting step (step S11) of preparing a test specimen E of the exterior wall 20, irradiating the brace 26 with electromagnetic waves B from the surface of the exterior wall 20, in the test specimen E, and setting the frequency of the electromagnetic waves B that enables detection of a component of reflected waves C which changes in accordance with the deformation of the brace 26 from the reflected waves C reflected by the brace 26; an irradiation and reception step (step S12) of irradiating the brace 26 with electromagnetic waves B of the set frequency from the surface of the exterior wall 20 of the building and receiving the reflected waves C reflected by the brace 26; and a deformation detection step (step S15) of detecting the deformation of the brace based on the component of the reflected waves.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method and system for detecting deformation of braces in the exterior walls of buildings. [Background technology]

[0002] Bracing made of metal plates is placed inside the exterior walls of steel-framed houses to improve earthquake resistance. During a major earthquake, the metal of the bracing stretches, absorbing seismic force and preventing the building from collapsing. After a major earthquake, the bracing must be inspected for yielding or breakage, and replacement or reinforcement is necessary, and non-destructive testing may be required to determine this. Whether the bracing has broken can be determined by the reaction of a metal detector. However, if the bracing has not broken, but the metal plate has stretched and deformed into a bow shape inside the exterior wall, it is difficult to determine the deformation using a metal detector.

[0003] Patent Document 1 discloses a technology for diagnosing the deterioration of the interior of exterior wall materials using electromagnetic waves. However, the technology described in Patent Document 1 does not determine the state of deformation of braces that occurs in hollow parts within the wall, and a technology that can easily determine the state of deformation of braces is desired. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2020-183919 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention was made in consideration of the above-mentioned situation, and the problem it aims to solve is to provide a brace deformation detection method and a brace deformation detection system that can easily detect the deformation state of braces placed inside an exterior wall. [Means for solving the problem]

[0006] The problem to be solved by the present invention is as described above, and the means for solving this problem will now be described.

[0007] That is, claim 1 provides a brace deformation detection method for detecting deformation of braces reinforcing the exterior wall of a building, comprising the steps of: preparing a test specimen of the exterior wall; irradiating electromagnetic waves from the surface of the exterior wall to the braces in the test specimen; and setting a frequency of the electromagnetic waves that enables detection of components of the reflected waves reflected by the braces, the components of the reflected waves changing in accordance with the deformation of the braces; an irradiation and reception process of irradiating electromagnetic waves of the set frequency from the surface of the exterior wall of the building to the braces and receiving the reflected waves reflected by the braces; and a deformation detection process of detecting deformation of the braces based on the components of the reflected waves.

[0008] In claim 2, the component of the reflected wave is either the amplitude ratio of the reflected wave to the amplitude of the electromagnetic wave at the set frequency, or the phase difference of the reflected wave to the electromagnetic wave at the set frequency.

[0009] In claim 3, the component of the reflected wave is either a real part or an imaginary part obtained by complex transforming the amplitude ratio and the phase difference.

[0010] In claim 4, in the frequency setting process, a first frequency group is set, which is the frequency of the electromagnetic wave at which the component of the reflected wave that changes according to the deformation of the diagonal brace can be detected; in the irradiating and receiving process, the electromagnetic wave of the first frequency group is irradiated and the reflected wave reflected by the diagonal brace is received; and in the deformation detection process, based on the component of the reflected wave, a state in which the distance from the back surface of the siding board of the exterior wall in the thickness direction of the exterior wall to the diagonal brace falls within a first range that is larger than when the diagonal brace is not deformed is detected, thereby detecting deformation of the diagonal brace.

[0011] In claim 5, in the frequency setting process, a second frequency group is set, which is the frequency of the electromagnetic wave at which the component of the reflected wave that changes according to the deformation of the diagonal brace can be detected; in the irradiating and receiving process, the electromagnetic wave of the second frequency group is irradiated and the reflected wave reflected by the diagonal brace is received; and in the deformation detection process, deformation of the diagonal brace is detected by detecting a state where the distance falls into a second range that is larger than the first range based on the component of the reflected wave.

[0012] Claim 6 provides a diagonal brace deformation detection system for detecting deformation of diagonal braces reinforcing the exterior walls of a building, comprising: an irradiation / reception device that irradiates electromagnetic waves from the surface of the exterior wall onto the diagonal braces, receives the waves reflected by the diagonal braces, and has a frequency set for the electromagnetic waves that enables detection of components of the reflected waves that change according to deformation of the diagonal braces; and a calculation device that performs calculations to detect deformation of the diagonal braces, and the calculation device detects deformation of the diagonal braces based on the components of the reflected waves received from the irradiation / reception device. [Effects of the Invention]

[0013] The present invention has the following effects.

[0014] According to claim 1, the deformation state of the braces arranged inside the exterior wall can be easily detected.

[0015] According to claim 2, the accuracy of detecting the deformation state of the brace can be improved.

[0016] According to claim 3, the accuracy of detecting the deformation state of the brace can be improved.

[0017] According to claim 4, it is possible to detect that the brace has been deformed so that the distance from the rear surface of the siding board to the brace in the thickness direction of the exterior wall falls within a first range.

[0018] According to claim 5, it is possible to detect deformation of the brace so that the distance from the rear surface of the siding board to the brace in the thickness direction of the exterior wall falls within the second range.

[0019] According to claim 6, the deformation state of the braces arranged inside the exterior wall can be easily detected. [Brief explanation of the drawings]

[0020] [Figure 1] 1A is a schematic side cross-sectional view showing the deformation detection system and an outer wall according to the embodiment, and FIG. 1B is a schematic plan cross-sectional view showing the deformation detection system and an outer wall according to the embodiment. [Figure 2] FIG. 1 is a schematic plan cross-sectional view showing an example of a test specimen. [Figure 3] 4A and 4B are diagrams for explaining complex transformation performed by a calculation device of the deformation detection system. [Figure 4] 1 is a flow diagram of a detection method using a deformation detection system. [Figure 5] Graph showing deformation detection results (imaginary part of 9.6 GHz). [Figure 6] Graph showing deformation detection results (real part at 10.0 GHz). [Figure 7] Graph showing deformation detection results (real part at 8.0 GHz). [Figure 8] Graph showing deformation detection results (real part at 9.6 GHz). DETAILED DESCRIPTION OF THE INVENTION

[0021] In the following description, the up / down direction and the left / right direction are defined according to the arrows shown in the drawings.

[0022] A method and system for detecting deformation of a brace according to an embodiment of the present invention will be described below.

[0023] 1. About exterior wall 20 As shown in FIG. 1, in this embodiment, the deformation detection system 10 detects the deformation state of a brace 26 arranged inside an exterior wall 20 of a building from the reflected waves of electromagnetic waves irradiated onto the exterior wall 20.

[0024] In this embodiment, the exterior wall 20 is a member corresponding to the exterior wall of the building to be inspected. In this embodiment, the building is a steel-framed house. The exterior wall 20 has a plurality of siding boards 21 on the exterior side and a gypsum board 28 on the interior side.

[0025] Examples of the siding board 21 include ceramic siding boards formed into boards using cementitious and fibrous materials as the main raw materials. The ceramic siding boards may be wood fiber reinforced cement boards, fiber reinforced cement boards, or fiber reinforced cement-calcium silicate boards.

[0026] A sealant (not shown) is filled between the siding boards 21 that form the exterior wall surface of the exterior wall 20. Between the siding board 21 and the gypsum board 28, a plurality of plywood panels 22 are provided at intervals in the left-right direction (the extension direction of the exterior wall 20) along the indoor surface of the siding board 21.

[0027] A steel frame 23 is provided between the plywood 22 and the gypsum board 28, along the indoor surface of the plywood 22. The steel frame 23 is made of U-shaped steel and is arranged with its longitudinal direction facing up and down. In one part of the exterior wall 20, the steel frame 23 is arranged relative to the plywood 22 at both ends of the three plywood panels 22 arranged horizontally, but is not arranged relative to the middle plywood 22. The two steel frames 23, 23 are arranged with their open sides facing each other.

[0028] A diagonal brace 26 is disposed between the steel frames 23, 23. The diagonal brace 26 is provided to reinforce the exterior wall 20. The diagonal brace 26 is made of a longitudinal metal plate and is disposed on the diagonal line between the two opposing steel frames 23, 23, with its longitudinal direction facing diagonally (from upper left to lower right, or from upper right to lower left). Note that because the diagonal brace 26 is disposed on the diagonal line between the steel frames 23, 23, the cross section of the diagonal brace 26 does not actually look like the cross sections shown in Figures 1 and 2, but for convenience, it is shown as shown in Figures 1 and 2. The diagonal brace 26 disposed in this manner can improve the earthquake resistance of the exterior wall 20 and, ultimately, the building.

[0029] Studs 25 are arranged between the steel frame 23 and the gypsum board 28. Furthermore, vertical furring strips 24 and studs 25 are arranged via diagonal braces 26 on the plywood 22 on which the steel frame 23 is not arranged (the middle plywood 22 of the three plywoods 22 arranged horizontally).

[0030] A fire-resistant material (fiber-based fire-resistant material) such as glass wool may be placed between the steel frame 23 and the vertical furring strips 24, and a dehumidifying sheet 27 is placed along the fire-resistant material. A ventilation layer 29 is formed between the dehumidifying sheet 27 and the gypsum board 28.

[0031] 2. Hardware of the Deformation Detection System 10 2-1. About the irradiation receiving device 3 The deformation detection system 10 includes an irradiation / reception device 3 that performs non-destructive testing of the braces 26 of the exterior wall 20 described above using electromagnetic waves B. As shown in Fig. 1, the irradiation / reception device 3 irradiates electromagnetic waves B of different frequencies each having a certain amplitude from the surface of the exterior wall 20 toward the interior of the exterior wall 20, and receives reflected waves C reflected by the exterior wall 20 at each frequency.

[0032] The irradiation receiving device 3 includes a housing 15. A handle 17 that an operator can hold is provided on one side of the housing 15. Wheels 13 are provided on the other side of the housing 15 at a position facing an outer wall 20, which is the object to be inspected. A transmitter 11 and a receiver 12 are arranged inside the housing 15.

[0033] The transmitter 11 is a device that irradiates electromagnetic waves B onto the exterior wall 20. The transmitter 11 is set to emit electromagnetic waves B having a predetermined amplitude and a constant frequency. The transmitter 11 irradiates the electromagnetic waves B in accordance with the rotation speed of the wheels 13. This allows the irradiation receiving device 3 (transmitter 11) to irradiate the electromagnetic waves B at constant intervals along the wall surface of the exterior wall 20, which will be described later.

[0034] 2-2. Frequency for detecting deformation of electromagnetic wave B emitted by transmitter 11 In this embodiment, electromagnetic waves B are irradiated onto the diagonal brace 26, and a deformation detection frequency of the electromagnetic waves is also set that can detect a component of the reflected waves C reflected by the diagonal brace 26, which changes depending on the distance from the transmitter 11 to the surface (the surface facing the outside) of the diagonal brace 26 in the horizontal direction (thickness direction of the exterior wall 20) (and thus the deformation state of the diagonal brace 26). The deformation detection frequencies include a first frequency group and a second frequency group.

[0035] 2-2-1. First frequency group of electromagnetic waves B emitted by transmitter 11 The first frequency group of electromagnetic waves B includes frequencies of electromagnetic waves B that are obtained by irradiating electromagnetic waves B from the surface (surface facing the outdoors) of the exterior wall 20 (siding board 21) to the diagonal brace 26, and detecting the component of reflected wave C reflected by the diagonal brace 26, which changes depending on the horizontal distance from the transmitter 11 to the surface of the diagonal brace 26 (and thus the horizontal distance La from the back surface (surface facing the indoors) of the siding board 21 to the surface of the diagonal brace 26).

[0036] More specifically, the frequencies of the first frequency group include frequencies of electromagnetic waves B that enable detection of components of reflected waves C of electromagnetic waves B when the electromagnetic waves B are irradiated onto the diagonal brace 26 whose distance La is within a first range. Here, the "first range" is set to a value greater than the distance La of the diagonal brace 26 in an undeformed state.

[0037] The frequencies of the first frequency group are not particularly limited as long as the component of the reflected wave C that changes in accordance with the change in distance La in the first range can be detected from the component of the reflected wave C. The frequency range of the first frequency group is preferably, for example, 7.0 GHz to 12.0 GHz, and multiple different frequencies can be set within this range. For example, the first frequency group includes two frequencies: (1) 9.6±0.2 GHz and (2) 10.0±0.2 GHz.

[0038] 2-2-2. Second frequency group of electromagnetic wave B emitted by transmitter 11 The second frequency group of electromagnetic waves B includes frequencies of electromagnetic waves B at which the component of reflected wave C reflected by the diagonal brace 26 can be detected when the electromagnetic waves B are irradiated from the surface of the exterior wall 20 (siding board 21) to the diagonal brace 26, and the component of reflected wave C that changes depending on the distance from the transmitter 11 to the surface of the diagonal brace 26 in the horizontal direction (and thus the distance La).

[0039] More specifically, the frequencies of the second frequency group include frequencies of the electromagnetic waves B that make it possible to detect components of the reflected waves C of the electromagnetic waves B when the electromagnetic waves B are irradiated onto the diagonal brace 26 whose distance La is within a second range. Here, the "second range" is set to a value greater than the first range.

[0040] The frequencies of the second frequency group are not particularly limited as long as the component of the reflected wave C that changes in accordance with the change in distance La in the second range can be detected from the component of the reflected wave C. The frequency range of the second frequency group is preferably, for example, 7.0 GHz to 12.0 GHz, and multiple different frequencies can be set within this range. For example, the second frequency group includes two frequencies: (3) 8.0±0.2 GHz and (4) 9.6±0.2 GHz.

[0041] 2-2-3. How to set the frequency for detecting deformation of electromagnetic wave B The following describes a method for setting the deformation detection frequencies (first frequency group, second frequency group) of the electromagnetic wave B. First, as shown in Figure 2, a test specimen of an exterior wall to be measured, or a test specimen of an exterior wall similar thereto (test specimen E), is prepared in advance.

[0042] Specimen E has a diagonal brace 26, and is arranged so that a non-deformed portion 26a and a deformed portion 26b are aligned in the longitudinal direction of the diagonal brace 26. Here, the non-deformed portion 26a is a portion where the distance La is the same as the original value (design value). On the other hand, the deformed portion 26b is a portion that has been deformed so that the distance La increases toward the tip (right end).

[0043] When setting the frequencies of the first frequency group, the electromagnetic wave B is irradiated onto the test piece while changing the frequency in stages so that a component of the reflected wave C that can distinguish the difference between the non-deformed portion 26a and the portion of the deformed portion 26b where the distance La is in the first range can be detected.

[0044] When setting the frequencies of the second frequency group, the electromagnetic wave B is irradiated onto the test piece while changing the frequency in stages so that a component of the reflected wave C that can distinguish the difference between the non-deformed portion 26a and the portion of the deformed portion 26b where the distance La is in the second range can be detected.

[0045] In this way, all frequencies comprising the abnormality detection frequencies (first frequency group and second frequency group) are set in the transmitter 11 of the irradiation and receiving device 3. The transmitter 11 can emit electromagnetic waves of the deformation detection frequencies in a stepwise manner.

[0046] 2-3. About receiver 12 The receiver 12 is a device that receives reflected waves C that are the result of electromagnetic waves B transmitted from the transmitter 11 being reflected by the exterior wall 20 (specifically, the diagonal braces 26). Here, the electromagnetic waves B transmitted (irradiated) by the transmitter 11 are either reflected by the surface of the siding board 21 or reflected by the diagonal braces 26 after being refracted, attenuated, and transmitted inside the exterior wall 20, etc.

[0047] At the set frequency of electromagnetic wave B, receiver 12 receives the waves resulting from the physical interference of these reflected waves as reflected wave C. Because the frequency of electromagnetic wave B is set such that it is difficult for it to be reflected or attenuated by siding board 21, but is easy to reflect by diagonal braces 26, and it is possible to distinguish between those reflected by siding board 21 and those reflected by diagonal braces 26, it is possible to distinguish between the two by the components of reflected wave C.

[0048] Furthermore, when the electromagnetic waves B of the deformation detection frequencies (first frequency group and second frequency group) are irradiated onto the diagonal brace 26, the components of the received reflected waves C contain information about the deformation state (degree of deformation) of the diagonal brace 26. These reflected waves C are recorded in a storage device (not shown) provided in the housing 15 or a storage device (not shown) provided together with the computing device 4. In this way, the receiver 12 can receive the reflected waves C of the deformation detection frequencies in response to the deformation detection frequencies.

[0049] The deformation detection system 10 includes a calculation device 4 that performs calculations to detect the deformation state (degree of deformation) of the diagonal brace 26, and a display device 5 that displays the results of calculations performed by the calculation device 4. In this embodiment, the calculation device 4 and the display device 5 are provided separately from the irradiation receiving device 3, but they may also be provided integrally with the irradiation receiving device 3.

[0050] 3. About the arithmetic unit 4 As shown in FIGS. 1(a) and 1(b), the calculation device 4 determines the deformation state (degree of deformation) of the diagonal brace 26 based on the components of the reflected wave C. The calculation device 4 calculates the amplitude ratio of the reflected wave C to the amplitude of the electromagnetic wave B at each frequency, and the phase difference of the reflected wave C relative to the electromagnetic wave B at each frequency. Here, since the reflected wave C is a waveform composed of multiple frequencies, the calculation device 4 may identify the frequency that is the main component of the reflected wave C (i.e., the frequency with the highest spectrum (largest amplitude)) by frequency analysis using FFT or the like, and calculate the amplitude ratio L and phase difference P from the amplitude and phase of the reflected wave C at the identified frequency. As an alternative method, the calculation device 4 may directly receive the reflected wave C, determine the phase of the peak period using the peak as the amplitude, and calculate the amplitude ratio L and phase difference P from these amplitudes and phases.

[0051] Here, the component of the reflected wave C used to determine the deformation state (degree of deformation) of the diagonal brace 26 may be either the amplitude ratio L of the reflected wave C to the amplitude of the electromagnetic wave B at the set frequency, or the phase difference P of the reflected wave C to the electromagnetic wave B at the set frequency. In other words, the threshold value of the amplitude ratio or phase difference that serves as the criterion for determining the deformation state of the diagonal brace 26 is set together with the frequency of the electromagnetic wave B from the above-mentioned experiment.

[0052] The calculation device 4 determines the deformation state of the diagonal brace 26 by comparing the magnitude of the calculated amplitude ratio L or phase difference P of the reflected waves C with a set threshold. Note that experiments by the inventors have shown that both the calculated amplitude ratio L and phase difference P of the reflected waves C change with the deformation of the diagonal brace 26. In this case, the deformation state (degree of deformation) of the diagonal brace 26 can be detected with high accuracy by comparing the magnitude of one of the amplitude ratio L and phase difference P of the reflected waves C with the corresponding threshold.

[0053] In addition, the deformation state (degree of deformation) of the diagonal brace 26 may be determined from the amplitude ratio L and phase difference P of the reflected wave C and threshold values ​​corresponding to the amplitude ratio L and phase difference P, and if it is determined that the diagonal brace 26 is deformed based on either of the determination results, it may be determined that the diagonal brace 26 is deformed.

[0054] Here, the component of the reflected wave C used to determine the deformation state of the diagonal brace 26 may be either the real part R or the imaginary part K obtained by complex transforming the amplitude ratio L and the phase difference P. The calculation device 4 performs complex transform on the amplitude ratio L and the phase difference P to calculate the real part R and the imaginary part K. Specifically, as shown in FIG. 3, points T corresponding to the amplitude ratio L and the phase difference P are plotted on a complex plane, and the values ​​of the real part R and the imaginary part K on the real axis and the imaginary axis are calculated. In this case as well, the threshold value of the real part R or the imaginary part K, which serves as the basis for determining the deformation state of the diagonal brace 26, is set together with the frequency of the electromagnetic wave B from the above-mentioned experiment.

[0055] The calculation device 4 determines the deformation state of the diagonal brace 26 by comparing the magnitude of the calculated complex-converted real part R and imaginary part K with the set threshold value. Note that experiments by the inventors have shown that both the complex-converted real part R and imaginary part K change with the deformation of the diagonal brace 26. Therefore, by comparing the magnitude of one of the complex-converted real part R or imaginary part K with the corresponding threshold value, the deformation state of the diagonal brace 26 can be detected with high accuracy. In this embodiment, the complex-converted real part R and imaginary part K are identification data on the same complex plane, so the deformation state of the diagonal brace 26 can be identified with high accuracy.

[0056] In addition, the deformation state of the brace 26 may be determined from the real part R, the imaginary part K, and their corresponding threshold values, and if either of the determination results indicates that the brace 26 is deformed, it may be determined that the brace 26 is deformed.

[0057] Furthermore, the calculation device 4 may calculate the average value of data at multiple positions calculated from the reflected wave C for the data (amplitude ratio L, phase difference P, real part R, or imaginary part K) used to determine the deformation, and determine the deformation by comparing the magnitude of this average value with a threshold value (the threshold value mentioned above) set for these data.

[0058] For example, when irradiating electromagnetic waves B of the first group of deformation detection frequencies consisting of the two frequencies shown in (1) and (2) above, the calculation device 4 uses (1) the imaginary part of 9.6±0.2 GHz and (2) the real part of 10.0±0.2 GHz as the identification data.Furthermore, when irradiating electromagnetic waves B of the second group of deformation detection frequencies consisting of the two frequencies shown in (3) and (4) above, the calculation device 4 uses (3) the real part of 8.0±0.2 GHz and (4) the real part of 9.6±0.2 GHz as the identification data.

[0059] A method for determining the deformation state of the brace 26 will be described below with reference to the flow chart of FIG.

[0060] In step S11, the frequency of the electromagnetic waves to be irradiated onto the exterior wall 20 is set. First, a test specimen E corresponding to the exterior wall 20 shown in FIG. 2 is prepared. Specifically, a test specimen is prepared that includes a brace 26 having a non-deformed portion 26a and a deformed portion 26b formed therein. The configuration of the test specimen E will be described in detail later.

[0061] Next, a control device (not shown) of the irradiation / reception device 3 irradiates electromagnetic waves B of multiple frequencies from the surface of the exterior wall 20, and receives reflected waves C for each frequency. At this time, among the electromagnetic waves B of multiple frequencies, a frequency of the electromagnetic waves B that provides a component of the reflected waves C that changes in accordance with the deformation of the diagonal brace 26 is selected and set. That is, for each frequency, the component of the reflected waves C described above is calculated, and from the calculated components, a frequency that clearly shows the difference between the non-deformed portion 26a and the deformed portion 26b of the diagonal brace 26 is selected and set as the frequency (first frequency group and second frequency group) of the electromagnetic waves B to be irradiated.

[0062] At this time, in order to distinguish between the component of the reflected wave C from the deformed portion 26b of the diagonal brace 26 and the component of the reflected wave C from the non-deformed portion 26a of the diagonal brace 26, threshold values ​​(the above-mentioned threshold values) for these are also set.

[0063] In specimen E shown in Fig. 2, the thickness t1 of the siding board 21 is 16 mm, the thickness t2 of the plywood 22 is 12 mm, and the length t3 in the thickness direction of the exterior wall 20 of the steel frame 23 is 60 mm. The deformed portion 26b is formed so as to bend from approximately the center of the diagonal brace 26 toward the indoor side. Specifically, the deformed portion 26b is deformed (bent) so that the distance La becomes longer toward the tip (rightward). More specifically, if the distance in the thickness direction of exterior wall 20 from the surface of siding board 21 to the surface of diagonal brace 26 is Lb, diagonal brace 26 is deformed at positions 1 to 6, which are set from left to right along the left-right direction, so that distance Lb = 28 mm (La = 12 mm) at position 1, distance Lb = 31.2 mm (La = 15.2 mm) at position 2, distance Lb = 34.4 mm (La = 18.4 mm) at position 3, distance Lb = 37.6 mm (La = 21.6 mm) at position 4, distance Lb = 40.8 mm (La = 24.8 mm) at position 5, and distance Lb = 44 mm (La = 28 mm) at position 6. The non-deformed portion 26a and the deformed portion 26b of specimen E thus formed are scanned by irradiation / reception device 3 while transmitting and receiving microwaves of 8.0 to 11.6 GHz, and data on amplitude ratio L and phase difference P are obtained.

[0064] FIG. 5 is a graph showing the deformation detection results (imaginary part of 9.6±0.2 GHz) obtained by complex transformation using the acquired amplitude ratio L and phase difference P. The horizontal axis represents the scanning coordinate, and positions 1 to 6 represent the left-right positions of the non-deformed portion 26a and the deformed portion 26b in the specimen E shown in FIG. 2. The value in parentheses on the horizontal axis represents the distance Lb in the deformed portion 26b, and the distance Lb in the non-deformed portion 26a is constant at 28 mm regardless of position. The values ​​in parentheses on the horizontal axis and positions 1 to 6 also apply to the graphs shown in FIGS. 6 to 8, which will be described later.

[0065] As shown in Figure 5, when the specific real part data (imaginary part of 9.6 ± 0.2 GHz) of the reflected wave C obtained by irradiating electromagnetic wave B having a frequency of 9.6 ± 0.2 GHz of the first frequency group is referenced, the real part data of the non-deformed portion 26a of the diagonal brace 26 from position 1 to position 3 is approximately the same at each position, and the slope of the regression line showing the data trend is close to zero. On the other hand, the real part data of the deformed portion 26b of the diagonal brace 26 is different from the real part data of the non-deformed portion 26a from position 1 to position 3, and decreases toward the right end of the diagonal brace 26, and the absolute value of the slope of the regression line showing the data trend is relatively large. Thus, there is a significant difference between the real part data of the non-deformed portion 26a and the real part data of the deformed portion 26b. Therefore, deformation of the diagonal brace 26 can be detected from positions 1 to 3 (corresponding to the "first range") where the distance from the surface of the siding board 21 to the surface of the diagonal brace 26 in the thickness direction of the exterior wall 20 is relatively short. In addition, since there is a linear relationship between the value of the real part data and the distance La, the degree of deformation of the diagonal brace 26 (distance La or Lb) can be obtained from the values ​​of the real part data from positions 1 to 3.

[0066] FIG. 6 is a graph showing the deformation detection results (real part of 10.0±0.2 GHz) obtained by complex transformation using the acquired amplitude ratio L and phase difference P.

[0067] As shown in Figure 6, when the specific real part data (real part of 10.0 ± 0.2 GHz) of the reflected wave C obtained by irradiating electromagnetic wave B having a frequency of 10.0 ± 0.2 GHz of the first frequency group is referenced, the real part data of the non-deformed portion 26a of the diagonal brace 26 from position 1 to position 3 is approximately the same at each position, and the slope of the regression line showing the data trend is close to zero. On the other hand, the real part data of the deformed portion 26b of the diagonal brace 26 is different from the real part data of the non-deformed portion 26a from position 1 to position 3 and increases toward the right end of the diagonal brace 26, and the absolute value of the slope of the regression line showing the data trend is relatively large. Thus, there is a significant difference between the real part data of the non-deformed portion 26a and the real part data of the deformed portion 26b. Therefore, deformation of the diagonal brace 26 can be detected from positions 1 to 3 (corresponding to the "first range") where the distance from the surface of the siding board 21 to the surface of the diagonal brace 26 in the thickness direction of the exterior wall 20 is relatively short. In addition, since there is a linear relationship between the value of the real part data and the distance La, the degree of deformation of the diagonal brace 26 (distance La or Lb) can be obtained from the values ​​of the real part data from positions 1 to 3.

[0068] FIG. 7 is a graph showing the deformation detection result (real part at 8.0 GHz) obtained by complex transformation using the acquired amplitude ratio L and phase difference P.

[0069] As shown in Figure 7, when the specific real part data (real part of 8.0 ± 0.2 GHz) of the reflected wave C obtained by irradiating electromagnetic wave B having a frequency of 8.0 ± 0.2 GHz of the second frequency group is referenced, the real part data of the non-deformed portion 26a of the diagonal brace 26 from position 4 to position 6 is approximately the same at each position, and the slope of the regression line showing the data trend is close to zero. On the other hand, the real part data of the deformed portion 26b of the diagonal brace 26 is different from the real part data of the non-deformed portion 26a from position 4 to position 6 and increases toward the right end of the diagonal brace 26, and the absolute value of the slope of the regression line showing the data trend is relatively large. Thus, there is a significant difference between the real part data of the non-deformed portion 26a and the real part data of the deformed portion 26b. Therefore, deformation of the diagonal brace 26 can be detected from position 4 to position 6 (corresponding to the "second range"), where the distance from the surface of the siding board 21 to the surface of the diagonal brace 26 in the thickness direction of the exterior wall 20 is relatively long. In addition, since there is a linear relationship between the value of the real part data and the distance La, the degree of deformation of the diagonal brace 26 (distance La or Lb) can be obtained from the value of the real part data from position 4 to position 6.

[0070] FIG. 8 is a graph showing the deformation detection result (real part of 9.6 GHz) obtained by complex transformation using the acquired amplitude ratio L and phase difference P.

[0071] As shown in Figure 8, when the specific real part data (real part of 9.6 ± 0.2 GHz) of the reflected wave C obtained by irradiating electromagnetic wave B having a frequency of 9.6 ± 0.2 GHz of the second frequency group is referenced, the real part data of the non-deformed portion 26a of the diagonal brace 26 from position 4 to position 6 is approximately the same at each position, and the slope of the regression line showing the data trend is close to zero. On the other hand, the real part data of the deformed portion 26b of the diagonal brace 26 is different from the real part data of the non-deformed portion 26a from position 4 to position 6 and increases toward the right end of the diagonal brace 26, and the absolute value of the slope of the regression line showing the data trend is relatively large. Thus, there is a significant difference between the real part data of the non-deformed portion 26a and the real part data of the deformed portion 26b. Therefore, deformation of the diagonal brace 26 can be detected from position 4 to position 6 (corresponding to the "second range"), where the distance from the surface of the siding board 21 to the surface of the diagonal brace 26 in the thickness direction of the exterior wall 20 is relatively long. In addition, since there is a linear relationship between the value of the real part data and the distance La, the degree of deformation of the diagonal brace 26 (distance La or Lb) can be obtained from the value of the real part data from position 4 to position 6.

[0072] In this way, the components of the reflected wave C are calculated, and from the calculated components, a frequency that clearly shows the difference between the non-deformed portion 26a and the deformed portion 26b of the brace 26 is selected, thereby setting the frequency (first frequency group and second frequency group) of the electromagnetic wave B to be irradiated.

[0073] Next, in step S12, an irradiation and reception step is performed. Specifically, electromagnetic waves B are irradiated onto the exterior wall 20 and the reflected waves are received. Specifically, as shown in FIG. 1, electromagnetic waves B having a set constant amplitude and constant frequency are irradiated from the surface of the exterior wall 20 toward the interior of the exterior wall 20, and reflected waves C reflected by the diagonal braces 26 are received.

[0074] Specifically, electromagnetic waves B are emitted and reflected waves C are received at multiple positions (for example, positions 1 to 6 described below) in the left-right direction (extension direction of exterior wall 20). More specifically, the following operations are performed. In this embodiment, since the diagonal braces 26 are not exposed, the positions of the diagonal braces 26 are identified from a design drawing or the like of the exterior wall 20. Next, while holding the handle 17 of the irradiation receiving device 3 shown in FIG. 1, the wheel 13 of the irradiation receiving device 3 is pressed against the surface of the siding board 21. Next, while rotating the wheel 13, the irradiation receiving device 3 is moved (scanned) along the identified positions of the diagonal braces 26, thereby emitting electromagnetic waves B and receiving reflected waves C.

[0075] In step S13, the calculation device 4 calculates the amplitude ratio L of the reflected wave C received at each position along the up-down direction at multiple positions in the left-right direction (e.g., positions 1 to 6) and the phase difference P of the reflected wave C relative to the electromagnetic wave B.

[0076] In step S14, the calculation device 4 performs complex transformation into a real part R and an imaginary part K of the amplitude ratio L and the phase difference P calculated for each position along the up-down direction at a plurality of positions in the left-right direction (for example, positions 1 to 6).

[0077] Finally, in step S15, the calculation device 4 detects the deformation state of the diagonal brace 26 based on the component (real part R or imaginary part K) of the reflected wave.

[0078] Specifically, when electromagnetic waves B of a frequency of the first frequency group (e.g., 9.6±0.2 GHz, 10.0±0.2 GHz) are irradiated onto the diagonal brace 26, the calculation device 4 detects the portion where the distance La is within the first range (the portion where the distance La of the diagonal brace 26 has been deformed so that it is not the original value but a value within the first range) based on the components of the multiple reflected waves C received at multiple positions on the diagonal brace 26 (e.g., the imaginary part of 9.6±0.2 GHz, the real part of 10.0±0.2 GHz). Furthermore, when electromagnetic waves B of frequencies in the second frequency group (e.g., 8.0±0.2 GHz, 9.6±0.2 GHz) are irradiated onto the diagonal brace 26, the calculation device 4 detects the portion where the distance La is within the second range (the portion where the diagonal brace 26 has been deformed so that the distance La is not the original value but a value within the second range) based on the components of the multiple reflected waves C received at multiple positions on the diagonal brace 26 (e.g., the real part of 8.0±0.2 GHz, the real part of 9.6±0.2 GHz).

[0079] In this way, by detecting the distance La to the diagonal brace 26, the degree of deformation of the diagonal brace 26 can be detected (grasp).

[0080] As described above, the deformation detection system 10 according to this embodiment can detect the yielding and deformation of the braces 26 arranged inside the exterior wall 20 without removing the siding board 21. It can also estimate the degree of deformation of the braces 26. This enables quantitative diagnosis of deterioration inside the exterior wall 20, which in turn enables early detection of defects and deterioration inside the exterior wall 20. This allows for appropriate maintenance of the exterior wall 20, and also makes it possible to determine repair methods, such as replacing or reinforcing the braces 26, and the costs involved in such repairs.

[0081] Furthermore, by moving the irradiation receiving device 3 along the siding board 21, it is possible to inspect and diagnose all parts inside the exterior wall 20. Furthermore, since there is no need to remove the siding board 21, the safety of the inspection can be improved and the inspection time can be shortened. Furthermore, since electromagnetic waves B in the microwave range are used, it is possible to make this an inspection method with high safety. Furthermore, if the irradiation receiving device 3 is used for another purpose (such as detecting deterioration of a sealing material), it can also be used for this purpose.

[0082] As described above, the brace deformation detection method according to this embodiment includes the following steps: A method for detecting deformation of a brace 26 reinforcing an exterior wall 20 of a building, comprising: a frequency setting step (step S11 in FIG. 4) of preparing a test specimen E of the exterior wall 20, irradiating electromagnetic waves B onto the diagonal braces 26 from the surface of the exterior wall 20 in the test specimen E, and setting a frequency of the electromagnetic waves B that enables detection of a component of the reflected waves C reflected by the diagonal braces 26, the component of the reflected waves C changing in accordance with the deformation of the diagonal braces 26; an irradiation and reception process (step S12) of irradiating the electromagnetic wave B of the set frequency from the surface of the exterior wall 20 of the building to the brace 26 and receiving the reflected wave C reflected by the brace 26; A deformation detection step (step S15) of detecting deformation of the brace based on the component of the reflected wave; It is equipped with the following.

[0083] With this configuration, the deformation state of the braces 26 arranged inside the exterior wall 20 can be easily detected.

[0084] Furthermore, the component of the reflected wave C is either the amplitude ratio L of the reflected wave C to the amplitude of the electromagnetic wave B at the set frequency, or the phase difference P of the reflected wave C to the electromagnetic wave B at the set frequency.

[0085] With this configuration, the accuracy of detecting the deformation state of the diagonal brace 26 can be improved.

[0086] The component of the reflected wave C is either a real part or an imaginary part obtained by complex transforming the amplitude ratio and the phase difference.

[0087] With this configuration, the accuracy of detecting the deformation state of the diagonal brace 26 can be improved.

[0088] In addition, in the frequency setting step, a first frequency group (e.g., 9.6±0.2 GHz, 10.0±0.2 GHz) is set, which is the frequency of the electromagnetic wave B at which the component of the reflected wave C that changes in accordance with the deformation of the brace 26 can be detected, In the irradiation and reception step, the electromagnetic wave B of the first frequency group is irradiated and the reflected wave C reflected by the brace 26 is received. In the deformation detection process, based on the components of the reflected wave C (for example, an imaginary part of 9.6±0.2 GHz and a real part of 10.0±0.2 GHz), deformation of the diagonal brace 26 is detected by detecting a state in which the distance from the back surface of the siding board 21 of the exterior wall 20 to the diagonal brace 26 in the thickness direction of the exterior wall 20 falls within a first range (for example, 12 mm to 20 mm) that is larger than the state in which the diagonal brace 26 is not deformed.

[0089] With this configuration, it is possible to detect that the diagonal brace 26 has been deformed so that the distance from the rear surface of the siding board 21 to the diagonal brace 26 in the thickness direction of the exterior wall 20 falls within the first range.

[0090] In addition, in the frequency setting step, a second frequency group (e.g., 8.0±0.2 GHz, 9.6±0.2 GHz) is set, which is the frequency of the electromagnetic wave B at which the component of the reflected wave C that changes in accordance with the deformation of the brace 26 can be detected, In the irradiation and reception step, the electromagnetic wave B of the second frequency group is irradiated and the reflected wave C reflected by the brace 26 is received. In the deformation detection process, the deformation of the brace 26 is detected by detecting a state in which the distance falls into a second range (e.g., 20 mm to 30 mm) that is larger than the first range based on the components of the reflected wave C (e.g., the real part of 8.0±0.2 GHz, the real part of 9.6±0.2 GHz).

[0091] With this configuration, it is possible to detect that the diagonal brace 26 has been deformed so that the distance from the rear surface of the siding board 21 to the diagonal brace 26 in the thickness direction of the exterior wall 20 falls within the second range.

[0092] Furthermore, the deformation detection system 10 according to this embodiment includes: A brace deformation detection system (10) for detecting deformation of a brace (26) reinforcing an exterior wall (20) of a building, comprising: an irradiation / reception device (3) that irradiates electromagnetic waves (B) from the surface of the exterior wall (20) to the braces (26), receives reflected waves (C) reflected by the braces (26), and has a frequency of the electromagnetic waves (B) set so that a component of the reflected waves (C) that changes in response to deformation of the braces (26) can be detected; A calculation device (4) for performing calculations to detect deformation of the brace (26), The arithmetic unit 4 The deformation of the brace 26 is detected based on the component of the reflected wave C received from the irradiation receiving device 3.

[0093] With this configuration, the deformation state of the braces 26 arranged inside the exterior wall 20 can be easily detected.

[0094] Although the embodiment of the present invention has been described above, the present invention is not limited to the above configuration, and various modifications are possible within the scope of the invention described in the claims.

[0095] For example, the frequency values ​​shown as the first frequency group and the second frequency group in this embodiment are merely examples, and are set appropriately depending on the specifications of the exterior wall 20, etc.

[0096] When electromagnetic waves B having a frequency in the first frequency group (9.6±0.2 GHz, 10.0±0.2 GHz) are irradiated, either (1) the imaginary part of 9.6±0.2 GHz or (2) the real part of 10.0±0.2 GHz may be used as the identification data, or a combination of both (1) the imaginary part of 9.6±0.2 GHz and (2) the real part of 10.0±0.2 GHz may be used as the identification data. When electromagnetic waves B having a frequency in the second frequency group (8.0±0.2 GHz, 9.6±0.2 GHz) are irradiated, either (3) the real part of 8.0±0.2 GHz or (4) the real part of 9.6±0.2 GHz may be used as the identification data, or a combination of both (3) the real part of 8.0±0.2 GHz and (4) the real part of 9.6±0.2 GHz may be used as the identification data.

[0097] In addition, in this embodiment, the degree of deformation is detected in two stages: the part where the distance La to the diagonal brace 26 is in a first range, and the part where it is in a second range, but the degree of deformation may also be detected in three or more stages. [Explanation of symbols]

[0098] 3. Irradiation receiving device 4 Arithmetic unit 10 Deformation detection system 20 Exterior Wall 21 Siding Board 26 Bracing

Claims

1. A method for detecting deformation of a brace that reinforces an exterior wall of a building, comprising: a frequency setting step of preparing a test specimen of the exterior wall, irradiating electromagnetic waves from the surface of the exterior wall to the braces in the test specimen, and setting a frequency of the electromagnetic waves that enables detection of a component of the reflected wave that changes in response to deformation of the braces from the reflected wave reflected by the braces; an irradiation and reception process of irradiating the electromagnetic wave of the set frequency from the surface of the exterior wall of the building to the brace and receiving the reflected wave reflected by the brace; a deformation detection step of detecting deformation of the brace based on the component of the reflected wave; Equipped with Bracing deformation detection method.

2. The component of the reflected wave is either an amplitude ratio of the reflected wave to the amplitude of the electromagnetic wave at the set frequency or a phase difference of the reflected wave to the electromagnetic wave at the set frequency. The method for detecting deformation of a brace according to claim 1.

3. The component of the reflected wave is either a real part or an imaginary part obtained by complex transforming the amplitude ratio and the phase difference. The method for detecting deformation of a brace according to claim 2.

4. In the frequency setting step, a first frequency group is set, which is a frequency of the electromagnetic wave at which a component of the reflected wave that changes in accordance with the deformation of the brace can be detected; In the irradiating and receiving step, the electromagnetic waves of the first frequency group are irradiated and the reflected waves reflected by the brace are received. In the deformation detection step, a state in which a distance from a rear surface of a siding board of the exterior wall to the brace in the thickness direction of the exterior wall falls within a first range that is larger than a state in which the brace is not deformed is detected based on the component of the reflected wave, thereby detecting deformation of the brace. The method for detecting deformation of a brace according to any one of claims 1 to 3.

5. In the frequency setting step, a second frequency group is set, which is a frequency of the electromagnetic wave at which a component of the reflected wave that changes in accordance with the deformation of the brace can be detected; In the irradiating and receiving step, the electromagnetic waves of the second frequency group are irradiated and the reflected waves reflected by the brace are received. In the deformation detection step, a state in which the distance falls within a second range greater than the first range is detected based on the reflected wave component, thereby detecting the deformation of the brace. The method for detecting deformation of a brace according to claim 4.

6. A brace deformation detection system for detecting deformation of a brace reinforcing an exterior wall of a building, an irradiation / reception device that irradiates electromagnetic waves onto the braces from the surface of the exterior wall, receives the waves reflected by the braces, and has a frequency set for the electromagnetic waves that enables detection of components of the reflected waves that change in response to deformation of the braces; A calculation device that performs calculations to detect deformation of the brace, The computing device detecting deformation of the brace based on the component of the reflected wave received from the irradiation receiving device; Bracing deformation detection system.

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