JP7175861B2 - TILE HEALTH DETERMINATION DEVICE AND METHOD - Google Patents

Description

The present invention relates to an apparatus and method for determining tile health.

Exterior wall tiles of buildings such as condominiums are obliged to carry out a percussive inspection of the entire surface every 10 years and report the result periodically. In the current general inspection method, an inspector hits the tiles one by one with a percussive stick or the like, and the soundness of defects such as floating is determined from the sound of the hammering. However, the soundness of the tiles is judged by the auditory sense of the inspector, and there is a possibility that the judgment result may be erroneous depending on the inspector's proficiency.

Therefore, it has been proposed to mechanically determine the soundness from the tapping sound of the tiles. For example, in Patent Document 1, a tile is hit using a hitting device that hits using a rotary solenoid, and the effective value of the frequency characteristics of the tile hitting sound judged to be sound is used as teacher data. There is disclosed a technique of calculating a correlation coefficient between individual tiles and measured data of hammering sounds, and diagnosing that the tiles are sound if the correlation coefficient is greater than a predetermined threshold.

JP-A-11-304773

However, since the impact force when the inspector hits the tiles with the tapping stick is not constant, even if the same tile is hit with the same tapping stick, the impact sound, especially the sound pressure level, will be different. For this reason, there is a high possibility that an erroneous determination will occur when the soundness is determined by comparing the hitting sound of the tile with the reference frequency characteristics (for example, teacher data described in Patent Document 1).

In addition, when using a device that provides a constant impact force, such as the percussion device disclosed in Patent Literature 1, introduction of such a device requires cost. In addition, since the hammering test is carried out over a wide area while the inspector is moving, if the equipment is large or heavy, the inspection work may become difficult. Furthermore, it is very difficult to make the striking force constant without mechanization, because it depends on the skill of each inspector.

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a tile soundness determination apparatus and method capable of reliably determining the soundness of tiles even if the impact force that vibrates the tiles changes. do.

The tile soundness determination apparatus of the present invention acquires frequency characteristics consisting of sound pressure levels in each frequency band divided into predetermined frequency intervals based on the tile hammering sound including the ambient sound detected by the microphone. A characteristic acquisition unit stores in advance a reference frequency characteristic consisting of a sound pressure level of each frequency band divided into the predetermined frequency interval based on sound hitting sound of the tile including ambient sound detected by the microphone. a reference frequency characteristic storage unit, a sound pressure relative level that is a relative sound pressure level in a predetermined frequency band of the frequency characteristic, and a sound pressure relative that is a relative sound pressure level in the frequency band of the reference frequency characteristic a specific sound pressure relative level difference calculating unit that calculates a specific sound pressure relative level difference that is a difference between the level and the sound pressure relative level that is a relative sound pressure level in each frequency band of the frequency characteristic and the reference frequency characteristic An average sound pressure relative level difference calculating unit that calculates an average sound pressure relative level difference that is the average of the difference between the sound pressure relative level that is the relative sound pressure level in the frequency band of the specific sound pressure relative level difference and the average sound pressure relative level difference exceeds a predetermined threshold, and the sound pressure relative level in each frequency band of the frequency characteristics and the frequency of the reference frequency characteristics a soundness judging unit for judging that the tile, which is the object to be judged , is unsound when the maximum value of the absolute value of the difference between the sound pressure relative levels in the band exceeds a predetermined threshold; The tiles are characterized by having the same type of tiles, the same type of adhesive used when attaching the tiles, and the same material as the base material on which the tiles are attached.

According to the tile soundness determination device of the present invention, the soundness determination section compares the frequency characteristics with the reference frequency characteristics after correcting using the specific sound pressure relative level difference or the average sound pressure relative level difference. . As a result, it is possible to eliminate the influence based on the difference in the sound pressure level generated from the tiles excited by the difference in the striking force of the sounding rod and the installation position of the microphone, etc., and the sound tile and the unsound tile It is possible to distinguish the differences in sound pressure level between the two on the basis of the frequency characteristics that characteristically change according to these differences. Therefore, it is possible to easily and reliably determine the soundness of the tile without using a device for making the excitation force such as the striking force constant.

The frequency characteristics of the sound generated when a tile is tapped are affected by factors such as the type of tile, the type of adhesive used when attaching the tile, and the material of the substrate on which the tile is attached, even if the tile is sound. differ by

Therefore, in the tile soundness determination apparatus of the present invention, the relative sound pressure of each frequency band divided into the predetermined frequency interval is based on the sound hitting sound of the tile including the ambient sound detected by the microphone. a reference frequency characteristic acquisition unit that acquires a frequency characteristic consisting of a sound pressure relative level that is a level, and the reference frequency characteristic storage unit stores the frequency characteristic acquired by the reference frequency acquisition unit as the reference frequency characteristic. preferable.

For example, in the tile soundness determination device of the present invention, it is preferable that the predetermined frequency band is a frequency band in which the sound pressure level of the frequency characteristics is the highest.

The tile soundness determination method of the present invention acquires the frequency characteristic consisting of the sound pressure level of each frequency band divided into predetermined frequency intervals based on the tile hammering sound including the ambient sound detected by the microphone. A reference frequency characteristic is stored in advance, which consists of a sound pressure level of each frequency band divided into the predetermined frequency interval, based on a characteristic acquisition step and a sound hammering sound of the tile including the ambient sound detected by the microphone. a reference frequency characteristic retrieving step of retrieving from the stored storage unit, a sound pressure relative level that is a relative sound pressure level in a predetermined frequency band of the frequency characteristic, and a relative sound pressure level in the frequency band of the reference frequency characteristic A specific sound pressure relative level difference calculating step of calculating a specific sound pressure relative level difference that is a difference from a certain sound pressure relative level, and a sound pressure relative level that is a relative sound pressure level in each frequency band of the frequency characteristics an average sound pressure relative level difference calculating step of calculating an average sound pressure relative level difference that is an average of differences from the sound pressure relative level that is the relative sound pressure level in the frequency band of the reference frequency characteristic; and the specific sound If the total value or maximum value of the absolute values of the differences between the pressure relative level difference and the average sound pressure relative level difference exceeds a predetermined threshold, and the sound pressure relative level in each frequency band of the frequency characteristics and the reference frequency and a soundness determination step of determining that the tile as the determination target is unsound when the maximum absolute value of the difference between the characteristics and the relative sound pressure level in the frequency band exceeds a predetermined threshold. The healthy tiles are characterized in that the type of tiles, the type of adhesive used in adhering the tiles, and the material of the base on which the tiles are adhered are the same as those of the tiles to be judged.

According to the tile soundness determination method of the present invention, in the soundness determination step, after correcting using the specific sound pressure relative level difference or the average sound pressure relative level difference, the frequency characteristic is compared with the reference frequency characteristic. . As a result, it is possible to eliminate the influence based on the difference in the sound pressure level generated from the tiles excited by the difference in the striking force of the sounding rod and the installation position of the microphone, etc., and the sound tile and the unsound tile It is possible to discriminate between the different hit sounds based on the frequency characteristics that characteristically change according to these differences. Therefore, it is possible to easily and reliably determine the soundness of the tile without using a device for making the excitation force such as the striking force constant.

1 is a block diagram of a tile soundness determination device according to an embodiment of the present invention; FIG. A graph showing the frequency response of a sound signal containing sound tile hits. Graph showing the combined maximum sound pressure level of the frequency response of a sound signal containing sound tile hits. Graph showing the frequency response of a sound signal containing unsound tile hits. Graph showing combined maximum sound pressure level of frequency response of sound signal including unsound tile hits. 4 is a flow chart of a tile soundness determination method according to an embodiment of the present invention;

A tile soundness determination device 10 according to an embodiment of the present invention will be described with reference to FIG.
The tile soundness determination device 10 detects defects such as floating, cracking, and chipping due to the sound generated by an inspector hitting or rubbing the tiles attached to the outer wall surface of a building such as an apartment building with a sounding stick or the like. It can be suitably used when performing a hammering test to determine.

The tile soundness determination device 10 is connected to the microphone 20 . The microphone 20 picks up the sound (sound) generated by the inspector hitting or rubbing the tile, which is the object to be judged, with the sounding rod, including the ambient sound, and detects the sound signal for the soundness of the tile. Send to device 10 .

The microphone 20 may be carried by the inspector or may be installed near the tile using a tripod or the like. The microphone 20 and percussive bar may be commercially available products.

The tile soundness determination device 10 is, for example, a personal computer or a PDA, and is capable of receiving sound signals from the microphone 20 by wire or wirelessly. Although details are not shown, the tile soundness determination device 10 includes an arithmetic processing unit including a CPU and a multiprocessor, a storage device including memories such as a ROM and a RAM, a transmitting/receiving device for transmitting/receiving data to/from a microphone, and an I/O circuit. etc.

The tile soundness determination device 10 includes an analog/digital (A/D) conversion unit 1 , a frequency characteristic acquisition unit 2 , a sound pressure relative level comparison unit 3 , a soundness determination unit 4 and a storage unit 5 .

The A/D converter 1 is a functional block that A/D converts an analog sound signal output from the microphone 20 into a digital sound signal. The A/D converter 1 outputs the A/D converted sound signal to the frequency characteristic acquisition unit 2 .

The frequency characteristic acquisition unit 2 acquires a frequency characteristic (spectrum) consisting of sound pressure levels in each frequency band divided into predetermined frequency intervals from the sound signal input from the microphone 20 via the A/D conversion unit 1. It is a functional block that The acquired frequency characteristics are, for example, frequency characteristics indicated by black dots in FIGS. 2A and 3A.

Specifically, the frequency characteristic acquisition unit 2 converts the sound signal input from the microphone 20 to a predetermined frequency such as a 1/3 octave band level using a known method such as fast Fourier transform (FFT). Divide into intervals and calculate the sound pressure level of each frequency band. Note that the frequency interval for division is not limited to the 1/3 octave band level, and may be a 1/1 octave band level, a 1/4 octave band level, or even a frequency such as 250 kHz. good.

However, it is preferable to remove a predetermined low frequency band or high frequency band from the frequency band for which the sound pressure level is to be calculated. This is because these frequency bands are not associated with tile strikes, particularly those characteristic of unhealthy tiles, and can be greatly influenced by ambient sounds other than tile strikes. . The frequency bands excluded from the calculation target may be, for example, a low frequency band of about 0 to 500 Hz and a high frequency band of over 10 kHz. Note that the sound data in these frequency bands may be removed by a low-pass filter, a high-pass filter, or the like before being input to the A/D converter 1 .

The sound pressure relative level comparison unit 3 is a functional block that relativeizes and compares the sound pressure levels of the frequency characteristics acquired by the frequency characteristics acquisition unit 2 and the reference frequency characteristics.

2A and 3A, the reference frequency characteristics of each frequency band divided into the predetermined frequency interval are based on the sound hitting sound of the tile including the ambient sound detected by the microphone 20. It is a frequency characteristic made up of sound pressure levels, and is stored in the storage unit 5 in advance. The storage section 5 corresponds to the reference frequency characteristic storage section of the present invention.

The frequency characteristics that occur when a tile is hit by a hammering test differ depending on the type of tile, the type of adhesive used when attaching the tile, the material of the substrate on which the tile is attached, etc., even if the tile is sound. . For this reason, it is preferable to use, as a reference frequency characteristic, frequency characteristics obtained for a plurality of sound tiles that are the same or similar to each other for the tiles subjected to the impact test.

Furthermore, it is more preferable to use the frequency characteristic obtained by the frequency characteristic obtaining unit 2 for the same tile attached to the outer wall of the same building as the tile to be subjected to the hammering test as the reference frequency characteristic. That is, for example, when a skilled inspector performs a hammering test on a plurality of tiles, for example, 30 tiles among the tiles to be subjected to the hammering test, and the tiles confirmed to be sound are subjected to the hammering test. It is preferable to use the average value of the frequency characteristics obtained in the above as the reference frequency characteristics.

The sound pressure relative level comparison section 3 has a specific sound pressure level difference calculation section 3a, an average sound pressure level calculation section 3b, a first comparison section 3c and a second comparison section 3d.

The specific sound pressure relative level difference calculator 3a, with reference to FIGS. A specific sound pressure relative level difference, which is a difference from the sound pressure relative level, which is the relative sound pressure level of the reference frequency characteristic in the frequency band, is calculated.

The sound pressure relative level in the predetermined frequency band is obtained by normalizing the sound pressure level in the predetermined frequency band by the sound pressure level of the entire frequency band. As the sound pressure level of the entire frequency band, for example, in addition to the all-pass (AP) value representing the synthesis level obtained by taking the sum of the sound pressure levels of all frequency components not passed through the band filter, the sound pressure level of the entire frequency component after passing through the band filter A value representing intensity, or the maximum sound pressure level in each frequency band may be used.

The average sound pressure relative level difference calculator 3b calculates the relative sound pressure level, which is the relative sound pressure level in each frequency band of the frequency characteristic, and the relative sound pressure level, which is the relative sound pressure level of the reference frequency characteristic in the frequency band. Calculate the average sound pressure relative level difference, which is the average of the difference from the level.

The first comparison unit 3c compares the total value or the maximum value of the difference between the specific sound pressure relative level difference and the average sound pressure relative level difference in each frequency band with a predetermined threshold value.

The second comparison unit 3d compares the total value or the maximum value of the difference between the sound pressure relative level in each frequency band of the frequency characteristic and the sound pressure relative level of the reference frequency characteristic in the frequency band with a predetermined threshold. The predetermined threshold in the first comparing section 3c is smaller than or equal to the predetermined threshold in the second comparing section 3c. As these thresholds, the unbiased standard deviation multiplied by a coefficient can be used.

The soundness determination unit 4 is a functional block that determines, based on the comparison result of the sound pressure level comparison unit 3, whether or not the tiles subjected to hammering inspection when sound is collected by the microphone 20 are sound. The soundness determination unit 4 determines whether the total value or the maximum value of the difference between the specific sound pressure relative level difference and the average sound pressure relative level difference exceeds a predetermined threshold in the comparison result of the first comparison unit 3c, or 2 If the comparison result in the comparison unit 3d shows that the maximum value of the difference between the sound pressure relative level in each frequency band of the frequency characteristics and the sound pressure relative level of the reference frequency characteristics in the frequency band exceeds a predetermined threshold, hammering test The tiles that are damaged are judged to be unhealthy.

Note that the soundness determination unit 4 may determine that the tile subjected to the hammering test is unsound when the comparison results of the first comparison unit 3c and the second comparison unit 3d both exceed the threshold values. Further, the sound pressure level comparison unit 3 includes only one of the first comparison unit 3c and the second comparison unit 3d, and the soundness determination unit 4 is based only on the comparison result of the first comparison unit 3c or the second comparison unit 3d. may be used to determine the soundness of the hammer tested tiles.

Further, the predetermined threshold value in the first comparison unit 3c and the second comparison unit 3d is determined to be unsound by the soundness determination unit 4 based on the comparison results in the first comparison unit 3c and the second comparison unit 3d. The value may be such that some tiles are actually healthy. However, conversely, the predetermined threshold value in the first comparison unit 3c and the second comparison unit 3d determines that the health determination unit 4 is healthy based on the comparison results in the first comparison unit 3c and the second comparison unit 3d. It should be a value with a margin so that tiles that are actually unhealthy do not fall into the tiles that are being processed.

The storage unit 5 stores the predetermined frequency interval divided by the frequency characteristic acquisition unit 2, the reference frequency characteristic, and the predetermined threshold values in the first comparison unit 3c and the second comparison unit 3c. .

The tile soundness determination device 10 preferably further includes an output control section 6 , a display section 7 and an alarm section 8 . However, these may be separate devices that are communicably connected to the tile health determination device 10 by wire or wirelessly.

The output control unit 6 is a functional block that controls processing for outputting the determination result based on the determination result output from the soundness determination unit 4 . The output control section 6 outputs a control signal related to the determination result to the display section 7 or the alarm section 8 .

The display unit 7 includes a monitor such as an LED display. When the soundness determination unit 4 determines that the tile is unsound, the display unit 7 displays information indicating that the hammering-inspected tile is unsound according to the control signal output from the output control unit 6. is displayed on a monitor or the like and notified to the inspector.

The alarm unit 8 includes a speaker for outputting voice messages and alarm sounds. When the soundness determination unit 4 determines that the tile is unsound, the alarm unit 8 outputs information indicating that the hammering-inspected tile is unsound by a control signal output from the output control unit 6. The inspector is warned by outputting a voice message or an alarm sound from a speaker or the like.

Based on the information output from the display unit 7 and the alarm unit 8, the inspector records the tiles determined to be unhealthy along with their positions on an input device such as a PDA or a drawing. Also, if the tiles that have undergone the hammering test are sound, it is preferable that the display section 7 or the alarm section 8 output a message to that effect, and the inspector records the information along with the positions on an input device or a drawing.

Furthermore, the determination result data of the soundness determination unit 4 and the tile position data may be associated and stored in the storage unit 5, and based on these, an unhealthy tile may be automatically identified.

Next, a tile soundness determination method according to an embodiment of the present invention using the tile soundness determination device 10 will be described with reference to FIG.

First, in the microphone installation step (STEP 1), the inspector installs the microphone 20 in the vicinity of the tile for hammering inspection.

Next, in the hammering test step (STEP 2), the inspector strikes or rubs the tiles to be subjected to the hammering test using a tapping stick. As a result, a sound collection step (STEP 3) is performed in which the microphone 20 collects the tapping sound of the tiles including the ambient sound.

Then, in the A/D conversion step (STEP 4), the A/D conversion unit 1 A/D converts the analog sound signal output from the microphone 20 into a digital sound signal, which is sent to the frequency characteristic acquisition unit 2. Output.

Next, in the frequency characteristic acquisition step (STEP 5), the frequency characteristic acquisition unit 2 obtains the sound signal input from the microphone 20 via the A/D conversion unit 1, and divides each frequency band into predetermined frequency intervals. Acquire the frequency response consisting of the sound pressure level.

Further, in the reference frequency characteristic extraction step (STEP 6 ), the sound pressure relative level comparison section 3 extracts the reference frequency characteristic from the storage section 5 .

Next, in the specific sound pressure relative level difference calculation step (STEP 7), the specific sound pressure relative level difference calculation unit 3a calculates the sound pressure relative level in a predetermined frequency band of the frequency characteristics acquired by the frequency characteristic acquisition unit 2 and the frequency A specific sound pressure relative level difference, which is a difference from the sound pressure relative level of the reference frequency characteristic in the band, is calculated.

Furthermore, in the average sound pressure relative level difference calculation step (STEP8), the average sound pressure relative level difference calculator 3b calculates the sound pressure relative level in each frequency band of the frequency characteristics and the sound pressure level of the reference frequency characteristic in the frequency band. Calculate the average sound pressure relative level difference, which is the average of the differences between

Next, in the first comparison step (STEP9), the first comparison unit 3c compares the total value or the maximum value of the difference between the specific sound pressure relative level difference and the average sound pressure relative level difference with a predetermined threshold value.

Further, in the second comparison step (STEP 10), the second comparison unit 3d sums the absolute values of the differences between the sound pressure relative level in each frequency band of the frequency characteristic and the sound pressure relative level of the reference frequency characteristic in the frequency band. A value or maximum value is compared with a predetermined threshold.

Next, in the soundness determination step (STEP 11), the soundness determination unit 4 determines whether the tiles tested by hammering when sound is collected by the microphone 20 are sound, based on the comparison result by the sound pressure relative level comparison unit 3. Determine whether or not

Furthermore, when the soundness determination unit 4 determines that the tiles subjected to the hammering test are unsound (STEP 11: YES), the output control unit 6 outputs a control signal so that in the output step (STEP 12), the display unit 7, and the alarm unit 8 issues an alarm to that effect in the alarm step (STEP 13).

When the soundness determination unit 4 determines that the tiles subjected to the hammering test are sound (STEP 11: NO), the output control unit 6 outputs a control signal so that in the output step (STEP 12), the display unit 7 to that effect. Furthermore, the alarm unit 8 may issue an alarm to that effect.

As described above, according to the tile soundness determination device 10 and the tile soundness determination method using the same according to the embodiment of the present invention, the sound pressure level is corrected using the specific sound pressure level difference, and then the frequency The characteristic is compared with the reference frequency characteristic. As a result, it is possible to eliminate the influence of the sound pressure level caused by the difference in the impact force of the inspector's tapping stick and the installation position of the microphone 20, and the difference in the hammering sound between the sound and unsound tiles can be eliminated by these measures. A comparison can be made based on the frequency characteristics that characteristically change according to the difference. Therefore, it is possible to easily and reliably determine the soundness of the tiles without using inspection equipment for making the striking force constant.

The reason why the soundness of the tiles can be determined by comparing the frequency characteristics by correcting using the specific sound pressure level difference is as follows.

The following equations (1) and (2) hold for the vibration acceleration level LV _A [dB], the impact force F, the acceleration Acc at the impact position, the sound pressure level L _P [dB], and the acoustic radiation coefficient k.
LV _A =20log ₁₀ F+20log ₁₀ (Acc) (1)
L _P =LV _A +10 log ₁₀ k (2)

Therefore, the striking force F and the sound pressure level Lp [dB] generated by the striking force F have the relationship expressed by the following equation (3).
L _P =20log ₁₀ F+20log ₁₀ (Acc) 10log ₁₀ k (3)

Here, assuming that the same tile is hit, the accelerance _Acc of the hitting position and the acoustic radiation coefficient k are the same. will depend on Therefore, a change in impact force _F results in a relative change in sound pressure level LP. This relationship holds for each frequency band.

It should be noted that the present invention is not limited to the tile soundness determination device 10 and the tile soundness determination method using the device specifically described in the above-described embodiment. If necessary, it can be changed as appropriate.

For example, in the above-described embodiments, the inspector hits or rubs the tiles with a percussive stick or the like, and the soundness of the tiles is determined based on the sound signal generated in the tiles. However, the present invention is not limited to this, and the soundness of the tiles may be determined based on information regarding vibrations generated by vibrating the tiles.

In this case, the inspector may vibrate the tiles by hitting or rubbing them with a percussion stick. Then, information on vibration may be acquired by a vibration information acquisition device, and the soundness of the tile may be determined based on the acquired information on vibration. The vibration information acquisition device is, for example, an acceleration sensor, velocity sensor, displacement sensor, or the like. Also, the vibration information acquisition device may be a non-contact type vibration detector such as a laser Doppler vibrometer.

Further, the tile soundness determination method of the present invention is not limited to being implemented in the tile soundness determination device 10 as described above. It can also be realized. Such programs can also be distributed via non-temporary recording media such as CD-ROMs (Compact Disc-Read Only Memory) and communication networks such as the Internet.

Reference Signs List 1 A/D conversion section 2 Frequency characteristic acquisition section 3 Sound pressure relative level comparison section 3a Specific sound pressure relative level difference calculation section 3b Average sound pressure relative level difference calculation section 3c First first Comparison unit 3d Second comparison unit 4 Soundness determination unit 5 Storage unit 6 Output control unit 7 Display unit 8 Alarm unit 10 Tile soundness determination device 20 Microphone.

Claims (4)

a frequency characteristic acquiring unit that acquires frequency characteristics consisting of sound pressure levels in each frequency band divided into predetermined frequency intervals based on the tile hitting sound including the ambient sound detected by the microphone;
A reference frequency characteristic storage in which a reference frequency characteristic consisting of sound pressure levels in each frequency band divided into the predetermined frequency intervals based on sound hitting sounds of tiles including ambient sounds detected by the microphone is stored in advance. Department and
A specific sound that is a difference between a sound pressure relative level that is a relative sound pressure level in a predetermined frequency band of the frequency characteristics and a sound pressure relative level that is a relative sound pressure level in the frequency band of the reference frequency characteristics a specific sound pressure relative level difference calculator that calculates the pressure relative level difference;
The average of the difference between the sound pressure relative level, which is the relative sound pressure level in each frequency band of the frequency characteristic, and the sound pressure relative level, which is the relative sound pressure level in the frequency band of the reference frequency characteristic an average sound pressure relative level difference calculator that calculates the sound pressure relative level difference;
When the total or maximum value of the absolute values of the difference between the specific sound pressure relative level difference and the average sound pressure relative level difference exceeds a predetermined threshold, and the sound pressure relative level in each frequency band of the frequency characteristics A soundness judging unit that judges that the tile, which is the object to be judged , is unsound when the maximum absolute value of the difference between the reference frequency characteristic and the sound pressure relative level in the frequency band exceeds a predetermined threshold. and
The healthy tiles are the same as those of the tiles to be determined, the type of tile, the type of adhesive used when attaching the tile, and the material of the substrate on which the tile is attached. Sex determination device. A frequency characteristic consisting of a sound pressure relative level, which is a relative sound pressure level of each frequency band divided into the predetermined frequency interval, based on sound hitting sound of the tile including ambient sound detected by the microphone. A reference frequency characteristic acquisition unit for acquiring
2. The tile soundness determination apparatus according to claim 1, wherein the reference frequency characteristic storage unit stores the frequency characteristic acquired by the reference frequency acquisition unit as the reference frequency characteristic. 3. The tile soundness determination device according to claim 1, wherein the predetermined frequency band is a frequency band in which the sound pressure level of the frequency characteristic is the highest. a frequency characteristic obtaining step of obtaining a frequency characteristic consisting of sound pressure levels in each frequency band divided into predetermined frequency intervals based on a tile hammering sound including ambient sound detected by a microphone;
A reference frequency characteristic consisting of a sound pressure level of each frequency band divided into the predetermined frequency interval is retrieved from a pre-stored storage unit based on sound hitting sound of the tile including ambient sound detected by the microphone. a reference frequency characteristic extraction step;
A specific sound that is a difference between a sound pressure relative level that is a relative sound pressure level in a predetermined frequency band of the frequency characteristics and a sound pressure relative level that is a relative sound pressure level in the frequency band of the reference frequency characteristics a specific sound pressure relative level difference calculating step of calculating the pressure relative level difference;
The average of the difference between the sound pressure relative level, which is the relative sound pressure level in each frequency band of the frequency characteristic, and the sound pressure relative level, which is the relative sound pressure level in the frequency band of the reference frequency characteristic an average sound pressure relative level difference calculating step of calculating the sound pressure relative level difference;
When the total or maximum value of the absolute values of the difference between the specific sound pressure relative level difference and the average sound pressure relative level difference exceeds a predetermined threshold, and the sound pressure relative level in each frequency band of the frequency characteristics A soundness judging step of judging that the tile, which is the object to be judged , is unsound when the maximum absolute value of the difference between the reference frequency characteristic and the sound pressure relative level in the frequency band exceeds a predetermined threshold. and
The healthy tiles are the same as those of the tiles to be determined, the type of tile, the type of adhesive used when attaching the tile, and the material of the substrate on which the tile is attached. Gender determination method.

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