JP6799982B2 - Abnormality detection method and abnormality detection device for linear body, and jig used for abnormality detection device for linear body - Google Patents

Description

The present invention relates to an abnormality detection method for a linear body, an abnormality detection device, and a jig used for the abnormality detection device for the linear body.

Conventionally, ultrasonic flaw detection is performed in order to detect breakage of each wire among cables composed of a plurality of wires.

For example, in the detection method described in Patent Document 1, an ultrasonic pulse is sent from the end of the wire of the cable to be the subject to the inside of the wire, and the reflection generated when the ultrasonic pulse is reflected at the broken portion. By receiving the signal at the end, the presence or absence of breakage of the wire and the breakage position are detected.

Japanese Unexamined Patent Publication No. 61-1146

In the detection method of Patent Document 1 described above, ultrasonic waves are transmitted from the end of the cable, the received reflected signal is detected, and the disconnection of the cable is detected. However, it is difficult for this detection method to detect small abnormalities that occur in the cable before the disconnection occurs, for example, abnormalities such as wall thinning and cracks. This is because even if you look at the amplitude of the received data acquired for a sound cable, it changes finely over time. The cause of this amplitude change is considered to be due to the interference of various waves as shown in (i) to (iv) below.

Here, in the cable to be detected, for example, a parallel wire cable having a button head provided at the end of the linear body, or a fixing tool such as a wedge is fixed to the end of the linear body with a tooth profile. PC steel stranded wire etc. are included. Therefore, the following four types of reflected waves (i) to (iv) obtained from the waves propagating in the cable after passing through the button head provided at the end of the cable and the tooth-shaped portion formed by the wedge. Can be considered.
(I) Reflection from the grain boundaries of the materials constituting the cable when transmitting from the end of the cable, passing through the button head provided at the end of the cable, the tooth profile due to the wedge, etc., and propagating in the cable. wave.
(Ii) A reflected wave caused by the roughness of the cable surface when propagating in the cable after passing through a button head, a tooth profile formed by a wedge, or the like.
(Iii) Of the waves propagating in the cable after passing through the tooth profile portion due to the button head or the wedge, the wave having the slower propagating speed is the grain boundary of the material constituting the cable or the roughness of the cable surface. Reflected wave caused by the wedge.
(Iv) Of the waves propagating in the cable after being reflected in the tooth profile portion by the button head or the wedge, the reflected wave caused by the grain boundaries of the materials constituting the cable or the roughness of the cable surface.

When detecting abnormalities in a linear body, a minute signal appearing in a received signal is used to detect the presence or absence of minute corrosion at a short distance, the presence or absence of cracks at a medium distance, or the presence or absence of a disconnection at a long distance. Need to be processed and judged. However, since the amplitude of the received signal changes with time due to the reflected waves such as (i) to (iv) above, by setting a certain threshold value, the presence or absence of minute corrosion at a short distance can be determined. , It is difficult to determine the presence or absence of cracks at medium distances and the presence or absence of disconnections at long distances.

Here, in order to detect an abnormality that is difficult to distinguish, such as the above-mentioned minute corrosion or long-distance disconnection, the sampling waveform created from the reflection signal of the wire of the subject is used as a reference for the reflection of the sound wire. It is conceivable to detect the presence or absence of an abnormality based on the magnitude of the amplitude difference of these sampling waveforms as compared with the sampling waveforms created from the signals.

However, since the wire of the inspection target has different end shapes and other conditions, the threshold value for determining the presence or absence of abnormality is set when detecting the presence or absence of abnormality by the amplitude difference between the two sampling waveforms. Difficult to set uniquely. Therefore, it is difficult to detect the presence or absence of an abnormality that is difficult to discriminate, such as minute corrosion of the wire, and to specify the position where the abnormality occurs.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an abnormality detection method capable of detecting an abnormality that is difficult to discriminate, such as minute corrosion of a linear body.

To solve the above problems, the method for detecting an abnormality in a linear body of the present invention is an abnormality detecting method for detecting an abnormality in the linear body of a subject, from the end of the linear body for reference. A step of transmitting ultrasonic waves toward the inside of the linear body to acquire received data for reference, preparing a sampling waveform for reference created using the received data for reference, and the subject. A step of transmitting ultrasonic waves from the end of the linear body toward the inside of the linear body to acquire the received data for the subject, and the process of using the received data for the subject for the subject. A step of creating a sampling waveform, a step of integrating the absolute value of the amplitude of the reference sampling waveform for each predetermined integration range to calculate a plurality of reference amplitude integrated values, and a sampling waveform for the subject. The step of integrating the absolute values of the amplitudes of the above for each predetermined integration range to calculate a plurality of amplitude integrated values for the subject, and the ratio of the amplitude integrated value for the subject and the amplitude integrated value for reference. Amplitude integration ratio is calculated for each predetermined integration range to obtain a plurality of the amplitude integration ratios, and when the determination value obtained from the plurality of amplitude integration ratios is equal to or higher than a predetermined threshold value. It is characterized by including a step of determining whether or not there is an abnormality.

Even if there are indistinguishable abnormalities such as minute corrosion inside the linear body, such as minute corrosion at a short distance, cracks at a medium distance, or disconnection at a long distance, transmission is performed from the end of the linear body. When the ultrasonic waves are reflected from the place where the abnormality occurs, the reflected signals are dispersed and continue for a while. This behaves differently from the noise contained in the reflected signal. Therefore, the present invention focuses on the behavior of such a reflected signal, and proposes a method of detecting an abnormality of the striatum using a determination value obtained from the amplitude integration ratio of the sampling waveform.

In this method, the amplitude integration ratio is obtained based on the sampling waveform of the subject and the sampling waveform for reference.

That is, a sampling waveform is created using the received data acquired when ultrasonic waves are transmitted to the linear body of the subject, and the absolute value of the amplitude of the sampling waveform is integrated for each predetermined integration range to be subject. Calculate multiple amplitude integrals for the sample. The plurality of amplitude integration values for the subject are compared with the plurality of reference amplitude integration values similarly calculated for the reference striatum for each predetermined integration range, and the plurality of amplitude integration ratios are calculated. ..

Then, when the determination value obtained from the plurality of amplitude integration ratios is equal to or higher than a predetermined threshold value, it is detected that the linear body of the subject has an abnormality. This is because the reflected signal is dispersed and lasts for a while in the place where there is an abnormality inside the linear body of the subject, so the abnormality is judged by focusing on the phenomenon that the increase in the amplitude integration ratio of the sampling waveform continues. Is. As a result, it is possible to accurately detect the occurrence of an abnormality in the striatum even when the reflected signal from an abnormal portion that is difficult to discriminate, such as minute corrosion or disconnection at a long distance, is small. Experiments by the inventors have revealed that the increase in the amplitude integration ratio in such anomalous parts is almost the same even if the shape of the end of the striatum of the subject and other conditions are different. ing. However, it has been confirmed by experiments that these amplitude integration ratios increase in places where abnormalities occur. Therefore, it is possible to uniquely set a threshold value for determining the presence or absence of an abnormality. Further, it is possible to specify the position corresponding to the vicinity of the integration range where such an increase in the amplitude integration ratio occurs as the location where the abnormality occurs in the striatum.

The determination value is preferably the amplitude integration ratio among the plurality of amplitude integration ratios.

According to this feature, since the amplitude integration ratio itself of the plurality of amplitude integration ratios is used as the determination value, it is possible to quickly identify the location of the abnormality of the striatum without complicated data processing. Is possible.

A step of integrating the absolute values of angle-related values related to the tilt angle with respect to the time axis at predetermined time intervals in the reference sampling waveform for each predetermined integration range to calculate a plurality of reference angle integrated values. A step of calculating a plurality of angle integrated values for a subject by integrating the absolute values of angle-related values related to the tilt angle with respect to the time axis at predetermined time intervals in the sampling waveform for the subject for each predetermined integration range. And a plurality of steps of calculating the angle integration ratio, which is the ratio of the angle integration value for the subject and the angle integration value for reference, for each of the predetermined integration ranges to obtain a plurality of the angle integration ratios. Further includes a step of calculating a plurality of ratio differences, which are differences between the amplitude integration ratio and the plurality of angle integration ratios, for each of the integration ranges, and the determination value is the said among the plurality of ratio differences. It is preferably a ratio difference.

According to this feature, the abnormality of the linear body can be detected accurately by using the ratio difference, which is the difference between the amplitude integration ratio and the angle integration ratio, as the judgment value obtained from the amplitude integration ratio of the sampled waveform. Is possible.

In this method, in addition to the above amplitude integration ratio, the angle integration ratio is obtained based on the sampling waveform of the subject and the sampling waveform for reference. That is, the absolute values of the angle-related values related to the tilt angle with respect to the time axis at predetermined time intervals in the sampling waveform for the subject are integrated for each predetermined integration range to calculate a plurality of angle integral values for the subject. A plurality of angle integration ratios are calculated by comparing the plurality of angle integration values for the subject with the plurality of reference angle integration values similarly calculated for the reference striatum for each predetermined integration range. ..

After that, a plurality of ratio differences, which are differences between the plurality of the amplitude integration ratios and the plurality of the angle integration ratios, are calculated for each of the integration ranges. Then, the ratio difference among the plurality of ratio differences is used as a determination value, and when the ratio difference is equal to or higher than a predetermined threshold value, it is detected that the linear body of the subject has an abnormality. This is because the reflected signal is dispersed and lasts for a while in the place where there is an abnormality inside the linear body of the subject, so that the change in the amplitude of the sampling waveform becomes larger than the change in the angle, and the above-mentioned amplitude integration ratio The abnormality is determined by paying attention to the phenomenon that the deviation between the angle integration ratio and the angle integration ratio continues. In this case, the amplitude integration ratio is affected by various factors, such as the shape of the end (for example, button head) of the linear body to which ultrasonic waves are transmitted and received, and the contact state of the ultrasonic probe. Even if it is received, the phenomenon that the above divergence continues does not change. As a result, it is possible to more accurately detect the occurrence of an abnormality in the striatum even when the reflected signal from an abnormal portion that is difficult to discriminate, such as minute corrosion or disconnection at a long distance, is small. The difference between the amplitude integration ratio and the angle integration ratio is less likely to change than the above-mentioned increase in the amplitude integration ratio even if the shape of the end of the linear body of the subject and other conditions are different. It has been clarified by experiments by the inventors. However, it has been confirmed by experiments that the amplitude integration ratio and the angle integration ratio deviate from each other in the place where the abnormality occurs. Therefore, it is possible to uniquely set a threshold value for determining the presence or absence of an abnormality. Further, it is possible to specify the position corresponding to the vicinity of the integration range where the deviation between the amplitude integration ratio and the angle integration ratio occurs as the abnormal occurrence location of the linear body.

The angle-related value is preferably an angle conversion value which is a ratio of the inclination angle to 90 degrees.

According to such a feature, it is possible to easily and accurately calculate the angle integral value by using the angle conversion value which is the ratio of the inclination angle to 90 degrees as the angle-related value.

The angle-related value may be the tilt angle itself. By using the tilt angle itself as an angle-related value, it is possible to easily and accurately calculate the angle integral value.

The angle-related value may be sin θ when the inclination angle is θ. By using sin θ when the inclination angle is θ as the angle-related value, it is possible to easily and accurately calculate the angle integral value.

The sampling frequency when creating the sampling waveform is preferably 2 to 10 times the frequency of the ultrasonic wave.

Within this range, a sampling waveform with a small deviation from the received data can be obtained, and an increase in the number of data required to form the sampling waveform can be suppressed.

The integration range is preferably in the range of 10 to 100 times the wavelength of the ultrasonic wave.

Within this range, the abnormality is not excessively detected due to the influence of the amplitude change of the sampling waveform, and the abnormality is not easily affected by the amplitude change and the abnormality is not overlooked.

The linear body preferably has a button head having a shape enlarged in the radial direction of the linear body at its end.

In the case of a linear body having such a button head, even if only one pulse of ultrasonic waves is emitted from the button head to the inside of the linear body, multiple reflections occur inside the button head, and the ultrasonic waves are reflected inside the linear body. Since the dispersion of sound waves becomes remarkable, it is difficult to detect anomalies inside the striatum. However, in the above-mentioned abnormality detection method, by using the determination value obtained from the above-mentioned amplitude integration ratio, the influence of the disturbance of the reflected signal due to the surface shape of the button head is reduced, so that the linear body can be used. It is possible to accurately detect abnormalities that are difficult to distinguish, such as minute internal corrosion and disconnection at long distances. Further, as in the case of the button head, when the fixing tool such as a wedge has a surface shape such as a PC steel stranded wire fixed by attaching a tooth profile to the end of the linear body, the reflected signal is disturbed due to the tooth profile portion. Since the influence of the above is reduced, it is possible to accurately detect abnormalities that are difficult to discriminate, such as minute corrosion inside the linear body and disconnection at a long distance.

The linear body of the subject is the wire in a wire cable composed of a plurality of strands, and the linear body for reference is the closest to the center of the wire cable among the plurality of strands. It is preferable that a wire is selected.

When detecting an abnormality in each wire of a wire cable composed of multiple wires, refer to it by selecting the wire closest to the center of the wire cable with the lowest occurrence of abnormality as the reference wire. Since it becomes possible to procure (prepare) the linear body for reference at the inspection work site, it is not necessary to carry the linear body for reference to the site or the like. This is particularly advantageous for high-altitude inspection work such as inspection of wire cables for bridges.

The linear body abnormality detection device of the present invention is an abnormality detection device that detects an abnormality in the linear body of a subject, and has a portion that can come into contact with the end portion of the linear body, and is formed from the end portion. An ultrasonic probe that transmits ultrasonic waves toward the inside of the linear body and acquires received data from the linear body, and a sampling waveform forming unit that forms a sampling waveform based on the received data. And the sample data storage unit that stores the sampling waveform related to the linear body of the subject formed by the sampling waveform forming unit, and the sampling waveform related to the reference linear body formed by the sampling waveform forming unit. The absolute values of the amplitudes of the reference data storage unit to be stored, the subject data storage unit, and the amplitude of the sampling waveform stored in the reference data storage unit are integrated for each predetermined integration range to be used for the subject and to be referred to. The amplitude integration unit that calculates a plurality of amplitude integration values for the purpose, and the amplitude integration ratio, which is the ratio between the amplitude integration value for the subject and the amplitude integration value for reference, are calculated for each of the predetermined integration ranges. , An amplitude integration comparison unit for obtaining a plurality of the amplitude integration ratios, and an abnormality determination unit for determining an abnormality when the determination value obtained from the plurality of amplitude integration ratios is equal to or higher than a predetermined threshold value. It is a feature.

According to this configuration, the sampling waveform forming unit creates a sampling waveform for the subject using the received data acquired when the ultrasonic probe transmits ultrasonic waves to the linear body of the subject. .. The amplitude integration unit integrates the absolute value of the amplitude of the sampling waveform for each predetermined integration range to calculate a plurality of amplitude integration values for the subject. The amplitude integral comparison unit compares the plurality of amplitude integral values for the subject with the plurality of reference amplitude integral values similarly calculated for the reference linear body for each predetermined integration range, and a plurality of amplitude integral values. Calculate the amplitude integration ratio. Then, the abnormality determination unit detects that the linear body of the subject has an abnormality when the determination value obtained from the plurality of amplitude integration ratios is equal to or higher than a predetermined threshold value. This is because the reflected signal is dispersed and lasts for a while in the place where there is an abnormality inside the linear body of the subject, so the abnormality is judged by focusing on the phenomenon that the increase in the amplitude integration ratio of the sampling waveform continues. Is. As a result, it is possible to accurately detect the occurrence of an abnormality in the striatum even when the reflected signal from an abnormal portion that is difficult to discriminate, such as minute corrosion or disconnection at a long distance, is small.

Wherein in the abnormality detecting apparatus of the linear body, and a frame portion attachable to the end portion of the linear body assembly with a linear body of multiple, in association with the frame portion, the ultrasonic probe It is preferable to further provide a jig having a holding portion that holds the linear body at a position corresponding to each end face and so as to face a direction corresponding to the normal direction of the end face of the linear body. ..

According to this configuration, when detecting an abnormality in an individual striatum among a plurality of striatums in a striatum assembly, the above-mentioned jig is used to move the ultrasonic probe to the striatum. It is fixed to the end face. That is, the frame portion of the jig is attached to the end portion of the linear body assembly, and in connection with the frame portion, the holding portion positions the ultrasonic probe at a position corresponding to each end surface of the linear body. In addition, the linear body is held so as to face the direction corresponding to the normal direction of the end face of the linear body. This makes it possible to bring the ultrasonic probe into contact with the end face of the striatum from a direction that coincides with the normal direction of the end face of the striatum, and the ultrasonic probe and the striatum can be brought into contact with each other. It is possible to suppress the variation in the contact state with the end face of the, thereby reducing the variation in the received signal.

The jig according to the present invention is a jig used in the above-mentioned abnormality detection device for a linear body, and has a frame portion that can be attached to an end portion of a linear body assembly having a plurality of linear bodies, and a frame portion. Holding the ultrasonic probe in association with the frame portion at a position corresponding to each end face of the striatum and facing the direction corresponding to the normal direction of the end face of the striatum. In a configuration having a portion and the linear body assembly further including a fixing portion that covers the outer periphery of the plurality of linear bodies in a state where the ends of the plurality of linear bodies are bundled, the frame portion is It is characterized by having a structure that can be attached to the end face of the fixing portion.

According to this configuration, when detecting an abnormality in an individual striatum among a plurality of striatums in a striatum assembly, the above-mentioned jig is used to move the ultrasonic probe to the striatum. It is fixed to the end face. That is, the frame portion of the jig is attached to the end portion of the linear body assembly, and in connection with the frame portion, the holding portion positions the ultrasonic probe at a position corresponding to each end surface of the linear body. In addition, the linear body is held so as to face the direction corresponding to the normal direction of the end face of the linear body. This makes it possible to bring the ultrasonic probe into contact with the end face of the striatum from a direction that coincides with the normal direction of the end face of the striatum, and the ultrasonic probe and the striatum can be brought into contact with each other. It is possible to suppress the variation in the contact state with the end face of the, thereby reducing the variation in the received signal.
Further, according to the above configuration, by fixing the frame portion to the end face of the fixing portion of the linear assembly, the ultrasonic probe is stably fixed to the end portion of the linear assembly via a jig. Is possible.

The jig according to the present invention is a jig used in the above-mentioned abnormality detection device for a linear body, and has a frame portion that can be attached to an end portion of a linear body assembly having a plurality of linear bodies, and the said frame portion. Holding the ultrasonic probe in association with the frame portion at a position corresponding to each end face of the striatum and facing the direction corresponding to the normal direction of the end face of the striatum. The holding portion has a through hole into which the ultrasonic probe can be fitted, and the through hole has the ultrasonic probe in a state where the ultrasonic probe is fitted. It is characterized by having an inner diameter of a size capable of holding the tentacle in a direction consistent with the normal direction of the end face of the linear body with respect to the end face of the linear body .

According to this configuration, when detecting an abnormality in an individual striatum among a plurality of striatums in a striatum assembly, the above-mentioned jig is used to move the ultrasonic probe to the striatum. It is fixed to the end face. That is, the frame portion of the jig is attached to the end portion of the linear body assembly, and in connection with the frame portion, the holding portion positions the ultrasonic probe at a position corresponding to each end surface of the linear body. In addition, the linear body is held so as to face the direction corresponding to the normal direction of the end face of the linear body. This makes it possible to bring the ultrasonic probe into contact with the end face of the striatum from a direction that coincides with the normal direction of the end face of the striatum, and the ultrasonic probe and the striatum can be brought into contact with each other. It is possible to suppress the variation in the contact state with the end face of the, thereby reducing the variation in the received signal.
Further, according to the above configuration, simply fitting the ultrasonic probe into the through hole of the holding portion causes the ultrasonic probe to be normal to the end face of the linear body with respect to the end face of the linear body. It is possible to make contact from the direction that matches the direction. As a result, the workability of the inspection work is improved.

The frame portion has an opening having an opening area capable of exposing the end faces of the plurality of linear bodies, and the holding portion includes a measuring part having the through hole and the measuring portion. It has a fixing part for fixing the part inside the opening, and the measuring part and the fixing part are fitted into the inside of the opening, so that the through hole of the measuring part is formed. It may be arranged at a position corresponding to the end face of the linear body.

According to such a configuration, it is possible to accurately set the through hole of the measurement part at the position of the end face of the linear body to be inspected among the plurality of linear bodies. As a result, by fitting the ultrasonic probe into the through hole, the ultrasonic probe is brought into contact with the end face of the striatum from a direction corresponding to the normal direction of the end face of the striatum. It becomes possible to make it.

The holding portion preferably has a structure capable of holding a plurality of the ultrasonic probes.

According to such a configuration, it is possible to bring the plurality of ultrasonic probes into contact with a plurality of linear bodies as a subject at the same time, and the workability of the inspection work is improved.

The holding portion may have a configuration capable of holding the ultrasonic probe so as to be arranged in a triangular shape.

According to such a configuration, the holding portion makes it possible to arrange the ultrasonic probes in a triangular shape, and as a result, the three ultrasonic probes are respectively placed on the end face of the linear body. It is possible to make an accurate contact from a direction that matches the normal direction of the end face of.

It is preferable to further include a selective connection portion for selectively connecting to an external device by selecting any one of the plurality of ultrasonic probes.

According to such a configuration, even when the holding portion holds a plurality of ultrasonic probes, it is possible to individually connect the ultrasonic probes to an external device by the selective connection portion.

As described above, according to the abnormality detection method and abnormality detection device for linear bodies of the present invention, it is possible to detect abnormalities that are difficult to discriminate, such as minute corrosion of linear bodies, for example, minute corrosion at short distances and medium distances. It is possible to detect a crack or a disconnection at a long distance.

According to the jig of the present invention, it is possible to suppress variations in the contact state between the ultrasonic probe and the end face of the linear body, thereby reducing variations in the received signal.

It is a block diagram which shows the basic structure of the abnormality detection apparatus of the linear body which concerns on 1st Embodiment of this invention. FIG. 5 is an enlarged cross-sectional view showing the end of the wire of the probe and the wire cable of FIG. It is a flowchart which shows the procedure of the abnormality detection method of the linear body which concerns on 1st Embodiment of this invention. It is explanatory drawing which shows roughly how the ultrasonic wave transmitted from the probe of FIG. 1 propagates inside the wire of a wire cable. It is a graph which shows the received waveform by the received data acquired from the sound wire for reference received by the probe of FIG. It is a figure which showed the formation of the sampling waveform schematically. It is a graph for demonstrating that the absolute value of the amplitude of the sampling waveform of FIG. 6 is integrated. It is a graph explaining that the sampling waveform formed from the received waveform of FIG. 5 is integrated with the absolute value of the amplitude for each predetermined integration interval T1. It is a graph which shows the amplitude integrated value for reference for each integration section calculated by integrating the absolute value of the amplitude for every predetermined integration section T1 of the sampling waveform of FIG. It is a graph explaining that the absolute value of the amplitude is integrated for every predetermined integration interval T1 in the sampling waveform formed from the received waveform of the wire of a subject. It is a graph which shows the amplitude integrated value for the subject for each integration section calculated by integrating the absolute value of the amplitude for every predetermined integration section T1 of the sampling waveform of FIG. (A) is a graph showing an example of a sampling waveform for reference, and (b) is a graph showing a plurality of amplitude integrated values obtained from the sampling waveform for reference in (a). (A) is a graph showing an example of a sampling waveform for a subject (an example of 50-day corrosion), and (b) shows a plurality of amplitude integral values obtained from the sampling waveform for the subject of (a). It is a graph. It is a graph which shows the amplitude integral ratio which is the ratio of the plurality of amplitude integral values for the subject of FIG. 13 (b) with respect to the plurality of amplitude integral values for reference of FIG. 12 (b). (A) is a graph showing another example (example of 100-day corrosion) of the sampling waveform for the subject, and (b) is a plurality of amplitude integrated values obtained from the sampling waveform for the subject of (a). It is a graph which shows. It is a graph which shows the amplitude integral ratio which is the ratio of the plurality of amplitude integral values for the subject of FIG. 15 (b) to the plurality of amplitude integral values for reference of FIG. 12 (b). It is a block diagram which shows the basic structure of the abnormality detection apparatus of the linear body which concerns on 2nd Embodiment of this invention. It is a flowchart which shows the procedure of the abnormality detection method of the linear body which concerns on 2nd Embodiment of this invention. It is a graph which shows the inclination angle θ with respect to the time axis for every predetermined time Δt of a sampling waveform. It is a graph of the angle conversion value for reference calculated from the sampling waveform of FIG. It is a graph which shows the angle integration value for reference for each integration section calculated by integrating the absolute value of the angle conversion value for reference of FIG. 20 for each predetermined integration section T1. It is a graph of the angle conversion value for a subject calculated from the sampling waveform of the subject formed by sampling the received data from the wire of the subject. It is a graph which shows the angle integral value for a subject for each integration section calculated by integrating the absolute value of the angle conversion value for a subject of FIG. 22 for each predetermined integration section T1. The amplitude integration ratio and the angle integration ratio for each integration section are shown, and the integration section No. It is a graph which shows the state that the amplitude integration ratio and the angle integration ratio are greatly deviated from 9 onward. (A) is a graph showing the change in amplitude and the change in angle in the sampling waveform, respectively, and (b) is a graph showing the degree of change in the amplitude integral value and the angle integral value. It is a graph which shows the guideline of the abnormality determination of a wire from the relationship between the distance from the end of a wire and the difference of ratio comparison. It is a figure which shows the state that the probe does not hit perpendicular to the end face of the wire when a probe is brought into contact with the end of each wire of a cable. It is explanatory drawing which shows the state which abutting the probe perpendicularly to a wire by using the jig used for the abnormality detection device of the linear body which concerns on 3rd Embodiment of this invention. FIG. 5 is an explanatory diagram showing a state in which a plurality of probes are collectively brought into contact with each wire of a cable using the jig of FIG. 28. It is a figure which shows the outer frame which comprises the split type jig which concerns on 3rd Embodiment of this invention. It is a figure which shows the measuring part corresponding to the outer frame of FIG. 30, which constitutes the split type jig which concerns on 3rd Embodiment of this invention. It is a figure which shows the fixing part corresponding to the outer frame of FIG. 30, which constitutes the split type jig which concerns on 3rd Embodiment of this invention. It is a figure which shows the end surface of the cable of FIG. It is a figure which shows the state which fixed the outer frame of FIG. 30 to the end face of a cable. Using a split-type split jig that combines the outer frame of FIG. 30, the measurement part of FIG. 31, and the fixing part of FIG. 32, the probes are arranged in a triangle, and a plurality of elements of the cable are arranged. It is a figure which shows the state of making contact with the end face of a wire at the same time. Using a split jig that combines the outer frame of FIG. 30, the measuring part of FIG. 31, and the fixing part of FIG. 32, the probes are arranged in a straight line to form a plurality of wires of the cable. It is a figure which shows the state of making contact with an end face at the same time. It is a figure which shows the probe which can be brought into contact with the end face of a plurality of strands of a cable at the same time.

Hereinafter, the abnormality detection method and the embodiment of the abnormality detection device of the present invention will be described in more detail with reference to the drawings.

(First Embodiment)
The abnormality detection device 1 of the first embodiment shown in FIG. 1 is a device that detects an abnormality in the linear body of a subject. The abnormality detection device 1 is a bridge cable 200 for suspending and supporting a cable composed of, for example, a plurality of strands 100 (for example, a bridge girder as shown in FIG. 27) as a linear body of a subject. Etc.), the abnormality of each wire 100 (for example, a small corroded portion 102) is detected by ultrasonic waves.

The wire 100 constituting the cable for a bridge is made of, for example, a galvanized steel wire having a diameter of about 7 mm, and the button head 101 having a shape enlarged in the radial direction of the wire 100 at the end of the wire 100. Has. The button head 101 has, for example, a substantially hemispherical shape, and its surface is curved. The linear body to be the subject and the shape of the end thereof are not particularly limited in the present invention. The linear body in the present invention may include not only a single wire but also a plurality of strands. For example, a parallel wire cable in which a plurality of strands are bundled in parallel, a wire rope in which a plurality of strands are twisted, a PC steel stranded wire, and the like are also included in the linear body of the present invention.

The abnormality detection device 1 includes a probe 2 (hereinafter referred to as a probe 2) and a measuring instrument 12 electrically connected to the probe 2 via a signal line. The measuring instrument 12 includes a reception data storage unit 3, a sampling waveform formation unit 4, a subject data storage unit 5, a reference data storage unit 6, an amplitude integration unit 7, an amplitude integration comparison unit 8, and an abnormality determination. A unit 9 is provided.

The probe 2 has a portion that can come into contact with the button head 101 at the end of the wire 100, transmits ultrasonic waves from the end to the inside of the wire 100, and has the wire 100. It has a configuration for acquiring received data from.

For example, the probe 2 shown in FIG. 2 is attached to a tubular main body case 2a, a piezoelectric element 2b and a wedge delay material 2c housed inside the main body case 2a, and an opening on the front side of the main body case 2a. It also has a soft retarder 2d. The piezoelectric element 2b is capable of transmitting ultrasonic waves and receiving reflected waves returned from the wire 100 as a subject to acquire received data. As the ultrasonic wave transmitted from the piezoelectric element 2b, for example, an ultrasonic wave having a frequency of about 2 to 5 MHz for flaw detection of a steel material is used, but an ultrasonic wave in a frequency range other than that may be used.

The wedge delay material 2c is made of a resin such as acrylic, and is fixed to the front surface of the piezoelectric element 2b by adhesion or the like. The soft delay material 2d is made of a material softer than the wedge delay material 2c, such as rubber, and is fixed to the front surface of the wedge delay material 2c by adhesion or the like. The soft retarder 2c has a recessed contact surface 2e that corresponds to the curved surface of the button head 101. Therefore, the contact surface 2e of the soft delay material 2c made of a soft material comes into close contact with the curved surface of the button head 101, so that the piezoelectric element 2b receives the reflected wave returned from the wire 100 via the wedge delay material 2c. It is possible to acquire received data with high stability and reproducibility.

The reception data storage unit 3 stores the reception data acquired by the probe 2.

The sampling waveform forming unit 4 forms a sampling waveform (for example, the sampling waveform W2 in FIG. 6) based on the received data stored in the received data storage unit 3.

The subject data storage unit 5 stores the sampling waveform related to the wire 100 of the subject formed by the sampling waveform forming unit 4.

The reference data storage unit 6 stores the sampling waveform related to the reference wire 100 formed by the sampling waveform forming unit 4. As the reference wire 100, for example, a sound wire having the same shape as the wire 100 of the subject and having no abnormality is adopted.

The reference wire 100 is a wire that is likely to have no abnormality among the plurality of wires constituting the bridge cable, specifically, at the center of the wire cable among the plurality of wires. The closest strand may be selected. When detecting an abnormality in each wire of a wire cable composed of a plurality of wires, the wire closest to the center of the wire cable with the lowest occurrence of abnormality is selected as the reference wire 100 as described above. This makes it possible to procure (prepare) the reference wire 100 separately from the wire of the wire cable of the subject at the inspection work site. Therefore, it is not necessary to bring the reference wire to the site or the like. This is particularly advantageous for high-altitude inspection work such as inspection of wire cables for bridges.

The amplitude integrating unit 7 integrates the absolute values of the amplitudes of the sampling waveforms stored in the subject data storage unit 5 and the reference data storage unit 6 for each predetermined integration range, and a plurality of objects for the subject and for reference. Calculate the amplitude integral value.

The amplitude integration comparison unit 8 calculates the amplitude integration ratio, which is the ratio of the amplitude integration value for the subject and the reference amplitude integration value, for each predetermined integration range, and obtains a plurality of the amplitude integration ratios.

The abnormality determination unit 9 uses the amplitude integration ratio of the plurality of amplitude integration ratios as a determination value obtained from the plurality of amplitude integration ratios, and when the amplitude integration ratio is equal to or higher than a predetermined threshold value, the abnormality is abnormal. Judge as yes.

The abnormality detection method for the linear body of the subject (specifically, the wire 100 of the bridge cable) using the abnormality detection device 1 configured as described above is executed by the procedure shown in the flowchart of FIG. Will be done.

First, ultrasonic waves are transmitted from the end of the wire 100 for reference toward the inside of the wire 100 to acquire the received data for reference, and the received data for reference is created by using the received data for reference. (Step S1 in FIG. 3). Here, the reference wire 100 is a galvanized steel wire having a button head 101 and having a diameter of about 7 mm and a length of 1 m, and a sound wire having no abnormality is used.

In order to acquire the received data for reference, specifically, as shown in FIG. 4, the probe 2 is brought into contact with the button head 101 of the reference wire 100 to wire the ultrasonic wave S. Send to the inside of 100. The ultrasonic wave S sends, for example, only one pulse at a frequency of 5 MHz (the speed transmitted inside the wire of the ultrasonic wave S is about 5700 m / s, and the wavelength is about 1.1 mm). The probe 2 receives the received data shown by the received waveform shown in FIG. 5 from the strand 100.

The ultrasonic wave S sent to the inside of the wire 100 is multiplely reflected inside the button head 101 as shown in FIG. Therefore, in the received waveform shown in FIG. 5, in the range D1 close to the probe 2, the amplitude A becomes large due to the multiple reflections inside the button head 101. Further, even in the intermediate range D2 inside the wire 100, the amplitude A is slightly affected by the multiple reflections at the button head 101 and the overlap of the reflections inside the wire 100. In the range D3, the amplitude change corresponding to the reflected wave at the end face on the side far from the probe 2 in the wire 100 is observed. In this range D3, it can be seen that the reflected wave is dispersed and lasts for a while. The duration of the reflected wave tends to be longer due to the influence of multiple reflections on the button head 101.

Next, the sampling waveform forming unit 4 forms a sampling waveform from the received data in the inspection range D in the received waveform shown in FIG. Specifically, as shown in FIG. 6, the received waveform W1 is sampled every time Δt, the amplitude value for each time Δt is extracted, and the sampled waveform W2 is formed by the group of the extracted amplitude values. ..

The time Δt is determined by the sampling frequency when the sampling waveform is created. That is, the time Δt is obtained as the reciprocal of the sampling frequency. The sampling frequency is preferably 2 to 10 times the frequency of the ultrasonic wave transmitted from the probe 2 (for example, the sampling frequency is preferably about 10 MHz with respect to the ultrasonic wave of 5 MHz). Within this range, a sampling waveform with a small deviation from the received data can be obtained, and an increase in the number of data required to form the sampling waveform can be suppressed.

If the reference sampling waveform is prepared before the examination of the striatum of the subject, it is not necessary to create the sampling waveform each time the examination of the striatum of the subject is performed.

Next, similarly to the reference wire 100, ultrasonic waves are transmitted from the end of the wire 100 of the subject toward the inside of the wire 100 to acquire the received data for the subject (FIG. Step S2 of 3). Then, a sampling waveform for the subject is created using the received data for the subject (step S3).

As shown in FIG. 1, the wire 100 for the subject has a corroded portion 102 (for example, a portion whose diameter is reduced by about 0.4 to 0.6 mm) as a small abnormality. Lines are used. Other points are the same specifications as the reference wire 100 (that is, a galvanized steel wire having a button head 101 and having a diameter of about 7 mm and a length of about 1 m).

Next, the amplitude integration unit 7 integrates the absolute value of the amplitude of the reference sampling waveform for each predetermined integration range T1 to calculate a plurality of reference amplitude integration values (step S4). Roughly speaking, the absolute value of the amplitude of the sampling waveform W2 shown in FIG. 6 (full-wave rectification that corrects the negative component of the amplitude) is obtained for each predetermined integration range T1 as shown in FIG. It is obtained by integrating into.

More specifically, as shown in FIG. 8, the sampling waveform formed from the received waveform obtained from the reference wire of FIG. 5 is divided into, for example, 15 pieces for each predetermined integration interval T1 (each integration interval). Is numbered with integration interval numbers 1 to 15). Then, as shown in FIG. 9, the sampling waveform of FIG. 8 is integrated with the absolute value of the amplitude for each predetermined integration interval T1, and as shown in FIG. 9, the reference amplitude for each integration interval T1. Calculate the integrated value.

Here, the integration range T1 is preferably in the range of 10 to 100 times the wavelength of the ultrasonic wave transmitted from the probe 2 (for example, when the wavelength of the ultrasonic wave is about 1.1 mm). The integration range T1 is preferably about 60 mm, which is about 50 times the wavelength thereof). Within this range, the abnormality is not excessively detected due to the influence of the amplitude change of the sampling waveform, and the abnormality is not easily affected by the amplitude change and the abnormality is not overlooked. Therefore, it becomes easy to distinguish between an abnormal signal and noise (that is, the S / N ratio increases).

Similar to the above, the amplitude integrating unit 7 integrates the absolute value of the amplitude of the sampled waveform for the subject for each predetermined integration range T1 as shown in FIG. 10, and is shown in FIG. A plurality of amplitude integrated values for the subject are calculated for each integration range T1 (step 4).

Next, the amplitude integration comparison unit 8 calculates the amplitude integration ratio, which is the ratio of the amplitude integration value for the subject and the reference amplitude integration value, for each predetermined integration range, and the plurality of the amplitude integration ratios B1. (Step 5 of the same).

Then, the abnormality determination unit 9 uses the amplitude integration ratio of the plurality of amplitude integration ratios as the determination value obtained from the plurality of amplitude integration ratios, and when the amplitude integration ratio is equal to or higher than a predetermined threshold value. Judge that there is an abnormality.

For example, the reference amplitude integral value corresponds to the reference sampling waveform (position 100 to 1000 mm from the end of the reference sound wire cable) shown in FIG. 12 (a) by the amplitude integrator 7. ) To the integration range divided into 15 pieces shown in FIG. 12 (b).

Similarly, the amplitude integration value for the subject is determined by the amplitude integration unit 7 for 50 days after applying salt water to the sampling waveform for the subject shown in FIG. 13 (a) (for example, about 500 mm from the end of the wire cable). From the corroded one), each of the 15 integration ranges shown in FIG. 13 (b) is obtained.

Then, by the amplitude integration comparison unit 8, the amplitude integration ratio B1, which is the ratio of the amplitude integration value for the subject in FIG. 13 (b) to the reference amplitude integration value in FIG. 12 (b), is shown in FIG. It is obtained for each of the 15 integration ranges shown in 14.

After that, the abnormality determination unit 9 determines that there is an abnormality when the amplitude integration ratio B1 shown in FIG. 14 is, for example, 2 or more as a predetermined threshold value.

Further, if the integration range in which the amplitude integration ratio B1 is equal to or higher than a predetermined threshold value is known, the position corresponding to the vicinity of the integration range can be specified as the abnormal occurrence location of the wire 100.

Further, when the amplitude integral value of FIG. 15 (b) is obtained from the sampling waveform of FIG. 15 (a) for the wire cable corroded for 100 days as another subject, the amplitude integration ratio B1 obtained from the amplitude integral value is also obtained. Will be as shown in FIG. In this case as well, the abnormality determination unit 9 can determine that there is an abnormality when the amplitude integration ratio B1 shown in FIG. 16 is within a predetermined threshold value (2 or more).

As shown in the flowchart of FIG. 3 above, in the abnormality detection method using the abnormality detection device 1 of the first embodiment, the amplitude integration ratio B1 is integrated within the integration range based on the sampling waveform of the subject and the sampling waveform for reference. Obtained for each T1. After that, when the amplitude integration ratio B1 among the plurality of amplitude integration ratios is equal to or higher than a predetermined threshold value, it is detected that the wire 100 of the subject has an abnormality. In this method, since the reflected signal is dispersed and lasts for a while in the place where there is an abnormality inside the wire 100 of the subject, the abnormality is determined by paying attention to the phenomenon that the increase in the amplitude integration ratio continues. As a result, it is possible to accurately detect the occurrence of an abnormality in the wire 100 even when the reflected signal from an abnormal portion that is difficult to discriminate, such as minute corrosion or disconnection at a long distance, is small.

Further, in the abnormality detection method of the first embodiment, the amplitude integration ratio itself among the plurality of amplitude integration ratios is used as a determination value obtained from the plurality of amplitude integration ratios. As a result, it is possible to quickly identify the location of the abnormality of the striatum without complicated data processing.

(Second Embodiment)
In the abnormality detection method of the first embodiment described above, the amplitude integration ratio itself among the plurality of amplitude integration ratios is used as the determination value obtained from the plurality of amplitude integration ratios, but the present invention is limited thereto. It's not a thing. Other determination values may be used as long as they are determination values obtained from a plurality of amplitude integration ratios.

In the abnormality detection method of the second embodiment, the abnormality of the linear body is accurately detected by using the ratio difference, which is the difference between the amplitude integration ratio and the angle integration ratio, as the judgment value obtained from the amplitude integration ratio of the sampled waveform. It can be detected well.

The abnormality detection device 1 used in the abnormality detection method of the second embodiment is configured as shown in FIG. The abnormality detection device 1 shown in FIG. 17 is composed of a probe 2 and a measuring device 12, similarly to the abnormality detecting device 1 of the first embodiment shown in FIG. 1, and the measuring device 12 receives the data. It includes a data storage unit 3, a sampling waveform forming unit 4, a subject data storage unit 5, a reference data storage unit 6, an amplitude integration unit 7, an amplitude integration comparison unit 8, and an abnormality determination unit 9. Since these configurations have already been described in the first embodiment, they will be omitted.

However, the anomaly detection device 1 shown in FIG. 17 is different from the anomaly detection device 1 of the first embodiment shown in FIG. 1 in that it further includes an angle integration unit 10 and an angle integration comparison unit 11.

The angle integration unit 10 sets the absolute value of the angle-related value related to the tilt angle with respect to the time axis for each predetermined time in the sampling waveform stored in the subject data storage unit 5 and the reference data storage unit 6 in a predetermined integration range. Integrate for each to calculate multiple angular integral values for the subject and for reference. As the angle-related value, for example, an angle conversion value which is a ratio of the inclination angle to 90 degrees is used. The angle-related value may be the tilt angle itself or sin θ with respect to the tilt angle θ.

The angle integration comparison unit 11 calculates the angle integration ratio, which is the ratio of the angle integration value for the subject and the angle integration value for reference, for each predetermined integration range, and obtains a plurality of the angle integration ratios.

In the abnormality detection method of the second embodiment, the angle integration ratio is obtained in addition to the above amplitude integration ratio based on the sampling waveform of the subject and the sampling waveform for reference. That is, the absolute values of the angle-related values related to the tilt angle with respect to the time axis at predetermined time intervals in the sampling waveform for the subject are integrated for each predetermined integration range to calculate a plurality of angle integral values for the subject. A plurality of angle integration ratios are calculated by comparing the plurality of angle integration values for the subject with the plurality of reference angle integration values similarly calculated for the reference striatum for each predetermined integration range. ..

Specifically, the abnormality detection method of the second embodiment is executed by the procedure shown in the flowchart of FIG.

In the abnormality detection method of the second embodiment, first, as in the flowchart of FIG. 3 of the abnormality detection method of the first embodiment, preparation of the sampling waveform of the reference cable (step S1) and reception data of the subject cable Acquisition (step S2), creation of a sampling waveform of the subject cable (step S3), amplitude integration of each sampling waveform of the reference cable and the subject cable (step S4), and calculation of the amplitude integration ratio (step S5) are performed. .. The specific description of steps S1 to S5 will be omitted because they have already been described in the first embodiment.

Next, the angle integration unit 10 integrates the absolute values of the angle-related values related to the tilt angle with respect to the time axis at predetermined time intervals in the reference sampling waveform for each predetermined integration range, and integrates a plurality of angles for reference. The value is calculated (step S11). Specifically, first, as shown in FIG. 19, the inclination angles θ _{1 to} θ ₁₀ ... Are obtained for each sampling time Δt of the sampling waveform W2. Then, when the angle conversion value R, which is the ratio of the tilt angle to 90 degrees, is adopted as the angle-related value, first, a graph of the time-series change of the angle conversion value R shown in FIG. 20 is obtained. Then, the absolute value of the angle conversion value R is integrated for each predetermined integration range T1 to calculate a plurality of reference angle integration values as shown in FIG.

Further, in the same manner as described above, the angle integrating unit 10 also obtains an angle-related value related to the inclination angle θ with respect to the time axis for each predetermined time Δt, as shown in FIGS. 22 to 23, for the sampling waveform for the subject. Specifically, the absolute value of the angle conversion value R) is integrated for each predetermined integration range T1 to calculate a plurality of angle integration values for the subject (step S11).

Then, the angle integration comparison unit 11 calculates the angle integration ratio B2, which is the ratio of the angle integration value for the subject and the angle integration value for reference, for each predetermined integration range, and obtains a plurality of angle integration ratios B2. Find (step S12).

Next, as shown in FIG. 24, the abnormality determination unit 9 is a plurality of ratios that are the difference between the plurality of amplitude integration ratios B1 obtained in step S5 and the plurality of angle integration ratios B2 obtained in step S12. The difference G is calculated for each integration range T1.

Then, the abnormality determination unit 9 uses the ratio difference G among the plurality of ratio differences G as a determination value, and determines that there is an abnormality when the ratio difference G is equal to or higher than a predetermined threshold value δ.

As shown in the flowchart of FIG. 18 above, in the abnormality detection method using the abnormality detection device 1 of the present embodiment, the amplitude integration ratio B1 and the angle integration ratio are based on the sampling waveform of the subject and the sampling waveform for reference. B2 is obtained for each integration range T1. After that, a plurality of ratio differences G, which is the difference between the plurality of amplitude integration ratios and the plurality of angle integration ratios, are calculated for each integration range. Then, the ratio difference among the plurality of ratio differences is used as a determination value, and when the ratio difference is equal to or higher than a predetermined threshold value δ, it is detected that the wire 100 of the subject has an abnormality. This is because the reflected signal is dispersed and continues for a while in the place where there is an abnormality inside the wire 100 of the subject, so that the change in the amplitude of the sampling waveform becomes larger than the change in the angle, and the above-mentioned amplitude integration ratio The abnormality is determined by paying attention to the phenomenon that the deviation between the angle integration ratio and the angle integration ratio continues. In this case, the amplitude integration ratio is affected by various factors such as the shape of the end portion (for example, the button head 101) of the wire 100 to which ultrasonic waves are transmitted and received and the contact state of the probe 2. Even if it is received, the phenomenon that the above divergence continues does not change. As a result, it is possible to more accurately detect the occurrence of an abnormality in the wire 100 even when the reflected signal from an abnormal portion that is difficult to discriminate, such as minute corrosion or disconnection at a long distance, is small.

For example, as shown in the sampling waveforms I and II shown in FIG. 25A, if the amplitude of the waveform I is doubled as in the waveform II, the integrated value of the amplitude A is also doubled in proportion to the amplitude A. become. However, even if the amplitude of the waveform I is doubled as in the waveform II, the upper limit of the tilt angle θ2 of the waveform II of the waveform I is 90 degrees, so that the tilt angle θ1 of the waveform I is doubled. It won't be simple. Therefore, the integrated value of the angle θ2 is not twice as large as the integrated value θ1 of the angle θ1. Therefore, as shown in FIG. 25B, it is considered that the amplitude integral C1 of the waveform and the angle integral C2 of the waveform deviate from each other as the amplitude increases.

Looking at the change in the ratio difference G, which is the difference between the amplitude integration ratio B1 and the angle integration ratio B2 shown in FIG. 24, a place where there is no abnormality, for example, the integration section No. in the graph of FIG. 24. 1-No. In the range of 7, even if the shape of the end of the wire 100 of the subject and other conditions are different, the increase in the amplitude integration ratio used as the determination value in the abnormality detection method of the first embodiment is obtained. Is even harder to change. However, the integration section No. which is the place where the abnormality occurs. Looking around 8-9, the No. In the range after 9, it is confirmed that the amplitude integration ratio B1 and the angle integration ratio B2 deviate from each other. Therefore, it is possible to uniquely set the threshold value δ for determining the presence or absence of an abnormality as a reference for the degree of deviation between the amplitude integration ratio B1 and the angle integration ratio B2.

Further, the position corresponding to the vicinity of the integration range (for example, integration interval No. 8 to 9) immediately before the integration range T1 where such a discrepancy between the amplitude integration ratio B1 and the angle integration ratio B2 occurs is set on the strand 100. It is possible to identify the location of the abnormality.

The ratio difference G, which is the difference between the amplitude integration ratio B1 and the angle integration ratio B2, tends to decrease as the distance from the end of the wire 100 (specifically, the button head 101) increases. Therefore, it is preferable to create an abnormality diagnosis map in which the distance L from the end shown in FIG. 26 and the ratio difference G are associated with each other. In this map, the regions defined by the two parameters of the distance L and the ratio difference G are divided into three regions corresponding to "break", "abnormality", or "healthy". For these three regions, the above two parameters (distance L and ratio difference G) and the state of the strands are determined by using the strands for the sample having artificial defects (disconnection, cracks, wall thinning due to corrosion, etc.). It is set by examining the relationship between. Using the diagnostic map shown in FIG. 26, if the distance L from the end and the ratio difference G are known, the state of the wire is either "broken", "abnormal", or "healthy". It is possible to easily and accurately determine whether or not this is the case. Further, if such a map is stored in the abnormality determination unit 9 or the like of the abnormality detection device 1 of FIG. 1, the abnormality detection device 1 can automatically diagnose the state of the strands at the inspection work site. It will be possible.

In the abnormality detection method of the above embodiment, since the angle conversion value which is the ratio of the tilt angle to 90 degrees is used as the angle-related value, the angle integral value can be calculated easily and accurately. .. Even if the tilt angle itself is used as the angle-related value, the angle integral value can be calculated easily and accurately. Further, even if sin θ when the inclination angle is θ is used as the angle-related value, the angle integral value can be calculated easily and accurately.

The wire 100, which is the subject of the abnormality detection method of the first embodiment and the second embodiment, has a button head 101 having a shape enlarged in the radial direction of the wire 100 at its end. In the case of the wire 100 having such a button head, even if only one pulse of ultrasonic waves is emitted from the button head to the inside of the wire 100, multiple reflections occur inside the button head, and the ultrasonic waves are reflected inside the wire 100. Since the dispersion of sound waves becomes remarkable, it is difficult to detect an abnormality inside the wire 100. However, in the above-mentioned abnormality detection method, the determination value obtained from the above-mentioned amplitude integration ratio (for example, the amplitude integration ratio itself in the first embodiment, or the amplitude integration ratio and the angle integration ratio in the second embodiment) By using (difference), the effect of disturbance of the reflected signal due to the surface shape of the button head is reduced, so it is possible to accurately detect abnormalities that are difficult to distinguish, such as minute corrosion inside the wire 100 and disconnection at a long distance. It is possible to do. Further, as in the case of the button head, when the fixing tool such as a wedge has a surface shape such as a PC steel stranded wire fixed by attaching a tooth profile to the end of the linear body, the reflected signal is disturbed due to the tooth profile portion. Since the influence of the above is reduced, it is possible to accurately detect abnormalities that are difficult to discriminate, such as minute corrosion inside the linear body and disconnection at a long distance.

As described above, the above-mentioned abnormality detection method is also useful for a method of forming a tooth profile on the surface of the striatum by a method of fixing (grasping) the striatum using a wedge or the like.

(Third Embodiment)
By using the abnormality detection methods of the first embodiment and the second embodiment described above, it is possible to individually detect an abnormality in a plurality of strands 201 (linear bodies) constituting the bridge cable 200 shown in FIG. 27. It is possible.

However, if the probe 2 is brought into contact with the end surface 201a of the wire 201 from the vertical direction and is not in normal surface contact, the state of transmitting ultrasonic waves from the probe 2 to the wire 201 and the probe The reception state of the reflected wave due to 2 becomes unstable, and the received signal may vary.

Therefore, in the present embodiment, the jig 21 shown in FIG. 28 is used in order to bring the probe 2 into normal surface contact with the end surface 201a of each wire 201 of the bridge cable 200.

Here, the bridge cable 200 shown in FIGS. 27 to 28 is a linear assembly including a plurality of strands 201 (linear bodies), and is, for example, a plurality of strands 201 and the plurality of strands 201. A fixing portion 202 that covers the outer periphery of the plurality of strands 100 in a state where the ends of the strands 100 are bundled is provided.

As shown in FIG. 28, the jig 21 includes a frame portion 22 and a holding portion 23 for holding the wire 201.

The frame portion 22 has a structure that can be attached to the fixing portion 202 that constitutes the end portion of the bridge cable 200. Specifically, the frame portion 22 has a contact surface 22a that can come into contact with the end surface 202a of the fixing portion 202, and is fixed to the end surface 202a by a fixing means such as a screw.

The holding portion 23 is associated with the frame portion 22 and has a direction in which the probe 2 is positioned at a position corresponding to each end face 201a of the wire 201 and coincides with the normal direction of the end face 201a of the wire 201. It has a structure that holds it so as to face. Specifically, the holding portion 23 is integrally formed with the frame portion 22. The holding portion 23 has a plurality of through holes 23a into which the probe 2 can be fitted. The plurality of through holes 23a are arranged at positions corresponding to the end faces 201a of the plurality of strands 201. Each through hole 23a holds the probe 2 in a direction corresponding to the normal direction of the end face 201a of the wire 201 with respect to the end face 201a of the wire 201 in a state where the probe 2 is fitted. It has an inner diameter of a size that allows it. The holding portion 23 may have a structure in which the probe 2 can be fitted in place of the through hole 23a.

When detecting an abnormality in each of the wires 201 of the bridge cable 201, the probe 2 is fixed to the end surface 201a of the wires 201 using the jig 21 described above. That is, if the frame portion 23 of the jig 21 is attached to the end surface 202a of the fixing portion 202 of the bridge cable 200, the through hole 23a of the holding portion 23 integrally formed with the frame portion 22 is the position of the end surface 201a of the wire 201. Placed in. In that state, if the probe 2 is inserted into the through hole 23a that exposes the wire 201 of the subject, the probe 2 is inserted at the position corresponding to each end face 201a of the wire 201 and the wire 201. It is possible to hold the end face 201a so as to face the direction corresponding to the normal direction. As a result, the probe 2 is brought into contact with the end face 201a of the wire 201 from a direction corresponding to the normal direction of the end face 201a of the wire 201 (that is, is brought into contact with the end face 201a from a direction perpendicular to the direction). ), And it is possible to suppress the variation in the contact state between the probe 2 and the end face 201a of the wire 201, thereby reducing the variation in the received signal.

Further, the jig 21 has a structure in which the frame portion 22 can be attached to the end surface 202a of the fixing portion 202. Therefore, by fixing the frame portion 22 to the end surface 202a of the fixing portion 202, the probe 2 can be stably fixed to the end portion of the bridge cable 200 via the jig 21.

Further, in the above jig 21, the holding portion 23 has a plurality of through holes 23a into which the probe 2 can be fitted. Each through hole 23a holds the probe 2 in a direction corresponding to the normal direction of the end face 201a of the wire 201 with respect to the end face 201a of the wire 201 in a state where the probe 2 is fitted. It has an inner diameter of a size that allows it. Therefore, simply by fitting the probe 2 into the through hole 23a of the holding portion, the probe 2 is placed in a direction that coincides with the normal direction of the end face 201a of the wire 201 with respect to the end face 201a of the wire 201. It becomes possible to make a contact. As a result, the workability of the inspection work is improved.

As shown in FIG. 29, if a plurality of probes 2 are inserted into the through holes 23a of the jig 21 in advance, the jig 21 can be fixed to the end surface 202a of the fixing portion 202, and a plurality of probes 2 can be inserted. It is possible to collectively contact the probe 2 of the above with respect to the end faces 201a of the plurality of strands 201 from the normal direction. Therefore, the workability of the inspection work is further improved.

Further, as shown in FIG. 29, the jig 21 is a changeover switch 24 as a selective connection unit for selecting any one of the plurality of probes 2 and selectively connecting the jig 21 to the measuring instrument 12 which is an external device. May be provided. In that case, even when the holding unit 23 holds a plurality of probes 2, the probes 2 can be individually connected to the measuring instrument 12 by the changeover switch 24.

Further, as shown in FIG. 29, it is preferable that the jig 21 has a recess 22b on the surface of the fixing portion 202 facing the end surface 202a, and the contact medium 25 is previously filled in the recess 22b. In this case, the contact medium 25 can be interposed between each probe 2 and the end face 201a of the wire 201 facing the probe 2, and it is possible to reduce variations in the ultrasonic wave reception state. .. Further, the work of applying the contact medium to each probe 2 becomes unnecessary.

In the jig 21 shown in FIGS. 28 to 29 above, the frame portion 22 and the holding portion 23 are integrally formed, but the present invention is not limited to this, and the frame portion 22 and the holding portion 22 are held. The unit 23 may be configured separately.

For example, by combining the frame portion 22 having the opening 22c shown in FIG. 30 and the holding portion 23 including the plurality of measuring parts 28 and the plurality of fixing parts 29 shown in FIGS. 31 to 32, FIG. The jig 21 shown in 35 to 36 may be configured.

The frame portion 22 shown in FIG. 30 has an opening 22c having an opening area capable of exposing the end faces 201a (see FIG. 33) of the plurality of strands 201. The size and shape of the opening 22c may be appropriately set according to the number and arrangement of the strands 201.

The measuring part 28 shown in FIG. 31 is composed of one or a plurality of hexagonal blocks, and each block has the above-mentioned through hole 23a into which the probe 2 is fitted. A plurality of hexagonal blocks are connected in a straight line or in a triangular shape.

The fixing part 29 shown in FIG. 32 is composed of one or a plurality of hexagonal blocks like the measurement part 28 described above, but does not have a through hole 23a.

Further, the peripheral wall 27 of the opening 22c of the frame portion 22 of FIG. 30 has a shape that can be fitted to the measuring part 28 and the fixing part 29 shown in FIGS. 31 to 32 above.

The measuring part 28 and the fixing part 29 may be a triangular or square block in addition to the hexagonal block.

When assembling the jig 21 shown in FIGS. 35 to 36 above, first, with respect to the end face 202a of the fixing portion 202 in which the end faces 201a of the plurality of strands 201 in the bridge cable 200 shown in FIG. 33 are exposed. , The frame portion 22 is fixed. The frame portion 22 is fixed to the end surface 202a of the fixing portion 202 by a plurality of bolts 26, for example, as shown in FIGS. 30 and 34. In this state, the end faces 201a of all the strands 201 are exposed through the opening 22c of the frame portion 22.

Then, as shown in FIGS. 35 to 36, with the probe 2 fitted in the through hole 23a of the measurement part 28, the through hole 23a of the measurement part is formed on the end surface 201a of the wire 201 of the subject. The measuring part 28 and the fixing part 29 are fitted into the opening 22c of the frame portion 22 so as to be arranged at the same positions. Therefore, it is possible to accurately set the through hole 23a of the measurement part at the position of the end surface 201a of the wire 201 of the subject among the plurality of wire 201. As a result, the probe 2 fitted in the through hole 23a can be brought into contact with the end surface 201a of the wire 201 from a direction corresponding to the normal direction of the end surface 201a of the wire 201. ..

In the jig 21 of FIG. 35, the three probes 2 are arranged in a triangular shape, and in the jig 21 of FIG. 36, the three probes 2 are arranged in a straight line. In this way, it is possible to bring the three (plural) probes 2 into contact with the end face 201a of the wire 201 of the subject at the same time. As a result, the workability of the inspection work is improved. In particular, as in the jig 21 of FIG. 35, the measuring parts 28 constituting the holding portion 23 hold the three probes 2 so as to arrange them in a triangular shape, so that the three probes 2 are respectively arranged. It is possible to accurately contact the end surface 201a of the wire 201 from a direction that coincides with the normal direction of the end surface 201a of the wire 201.

It should be noted that, instead of the configuration in which the plurality of probes 2 are held by the measuring parts 28 as in the jig 21 shown in FIGS. 35 to 36, the end faces of the plurality of strands 201 are shown in FIG. 37. Large-sized probes 30 and 31 capable of collectively contacting the 201a may be used, in which case the inspection time can be shortened.

1 Abnormality detection device 2 Ultrasonic probe 4 Sampling waveform forming unit 5 Subject data storage unit 6 Reference data storage unit 7 Amplitude integration unit 8 Amplitude integration comparison unit 9 Abnormality judgment unit 10 Angle integration unit 11 Angle integration comparison unit 21 Jig 22 Frame part 22c Opening part 23 Holding part 23a Through hole 24 Changeover switch (selective connection part)
28 Measurement parts 29 Fixing parts 100 Striatum (striatum)
101 Button head 102 Corroded part 200 Bridge cable 201 Wire 202 Fixing part

Claims (18)

An anomaly detection method that detects anomalies in the striatum of the subject.
Ultrasonic waves are transmitted from the end of the striatum for reference to the inside of the striatum to acquire received data for reference, and sampling for reference created using the received data for reference. The process of preparing the waveform and
A step of transmitting ultrasonic waves from the end of the linear body of the subject toward the inside of the linear body to acquire received data for the subject, and
A step of creating a sampling waveform for a subject using the received data for the subject, and
A step of integrating the absolute value of the amplitude of the sampling waveform for reference for each predetermined integration range to calculate a plurality of amplitude integrated values for reference.
A step of integrating the absolute value of the amplitude of the sampling waveform for the subject for each predetermined integration range to calculate a plurality of amplitude integrated values for the subject.
A step of calculating an amplitude integral ratio, which is a ratio of an amplitude integral value for a subject and an amplitude integral value for reference, for each of the predetermined integration ranges to obtain a plurality of the amplitude integral ratios.
A method for detecting an abnormality in a linear body, which comprises a step of determining whether or not there is an abnormality when a determination value obtained from the plurality of amplitude integration ratios is equal to or higher than a predetermined threshold value. The determination value is the amplitude integration ratio among the plurality of amplitude integration ratios.
The method for detecting an abnormality in a linear body according to claim 1. A step of integrating the absolute values of angle-related values related to the tilt angle with respect to the time axis at predetermined time intervals in the reference sampling waveform for each predetermined integration range to calculate a plurality of reference angle integral values.
A step of calculating a plurality of angle integral values for a subject by integrating the absolute values of angle-related values related to the tilt angle with respect to the time axis at predetermined time intervals in the sampling waveform for the subject for each predetermined integration range. When,
A step of calculating the angle integration ratio, which is the ratio of the angle integration value for the subject and the angle integration value for reference, for each of the predetermined integration ranges to obtain a plurality of the angle integration ratios.
A step of calculating a plurality of ratio differences, which is a difference between the plurality of the amplitude integration ratios and the plurality of the angle integration ratios, for each of the integration ranges.
Including
The method for detecting an abnormality in a linear body according to claim 1, wherein the determination value is the ratio difference among the plurality of ratio differences. The angle-related value is an angle conversion value which is a ratio of the inclination angle to 90 degrees.
The method for detecting an abnormality in a linear body according to claim 3. The angle-related value is the tilt angle itself.
The method for detecting an abnormality in a linear body according to claim 3. The method for detecting an abnormality in a linear body according to claim 3, wherein the angle-related value is sin θ when the inclination angle is θ. The sampling frequency when creating the sampling waveform is 2 to 10 times the frequency of the ultrasonic wave.
The method for detecting an abnormality in a linear body according to any one of claims 1 to 6. The integration range is 10 to 100 times the wavelength of the ultrasonic wave.
The method for detecting an abnormality in a linear body according to any one of claims 1 to 7. The linear body has a button head having a shape enlarged in the radial direction of the linear body at its end.
The method for detecting an abnormality in a linear body according to any one of claims 1 to 8. The linear body of the subject is the wire in a wire cable composed of a plurality of wires.
As the reference wire, the wire closest to the center of the wire cable is selected from the plurality of wires.
The method for detecting an abnormality in a linear body according to any one of claims 1 to 9. An abnormality detection device that detects abnormalities in the striatum of the subject.
An ultrasonic wave having a portion that can be contacted with an end portion of the linear body, transmitting ultrasonic waves from the end portion toward the inside of the linear body, and acquiring received data from the linear body. With a probe,
A sampling waveform forming unit that forms a sampling waveform based on the received data,
A subject data storage unit that stores a sampling waveform related to the striatum of the subject formed by the sampling waveform forming unit,
A reference data storage unit that stores a sampling waveform related to the reference linear body formed by the sampling waveform forming unit, and a reference data storage unit.
A plurality of amplitude integrated values for the subject and the reference are calculated by integrating the absolute values of the amplitudes of the sampling waveforms stored in the subject data storage unit and the reference data storage unit for each predetermined integration range. Amplitude integrator and
An amplitude integration comparison unit that calculates the amplitude integration ratio, which is the ratio of the amplitude integration value for the subject and the amplitude integration value for reference, for each of the predetermined integration ranges to obtain a plurality of the amplitude integration ratios.
An abnormality detection device for a linear body including an abnormality determination unit for determining an abnormality when a determination value obtained from the plurality of amplitude integration ratios is equal to or higher than a predetermined threshold value. A frame portion which can be attached to the end of the linear body assembly with a linear body of multiple,
In association with the frame portion, the ultrasonic probe is held at a position corresponding to each end face of the striatum and so as to face in a direction corresponding to the normal direction of the end face of the striatum. Has a holding part,
The abnormality detection device for a linear body according to claim 11, further comprising a jig. A jig used in the linear abnormality detection device according to claim 11.
A frame that can be attached to the end of a striatal assembly with multiple striatum
In association with the frame portion, the ultrasonic probe is held at a position corresponding to each end face of the striatum and so as to face in a direction corresponding to the normal direction of the end face of the striatum. Has a holding part and
In a configuration in which the linear body assembly further includes a fixing portion that covers the outer periphery of the plurality of linear bodies in a state where the ends of the plurality of linear bodies are bundled.
The frame portion has a structure that can be attached to the end face of the fixing portion .
Jig. A jig used in the linear abnormality detection device according to claim 11.
A frame that can be attached to the end of a striatal assembly with multiple striatum
In association with the frame portion, the ultrasonic probe is held at a position corresponding to each end face of the striatum and so as to face in a direction corresponding to the normal direction of the end face of the striatum. Has a holding part and
The holding portion has a through hole into which the ultrasonic probe can be fitted.
The through hole holds the ultrasonic probe in a direction that coincides with the normal direction of the end face of the linear body with respect to the end face of the linear body in a state where the ultrasonic probe is fitted. has a size inside diameter of which can be,
Jig. The frame portion has an opening having an opening area capable of exposing the end faces of the plurality of linear bodies.
The holding part is
The measuring part having the through hole and
It has a fixing part for fixing the measuring part inside the opening.
By fitting the measuring part and the fixing part into the inside of the opening, the through hole of the measuring part is arranged at a position corresponding to the end face of the linear body.
The jig according to claim 14. The holding portion has a configuration capable of holding a plurality of the ultrasonic probes.
The jig according to any one of claims 13 to 15. The holding portion has a configuration capable of holding the ultrasonic probe so as to be arranged in a triangle.
The jig according to claim 15. Further comprising a selective connection portion for selecting any one of the plurality of ultrasonic probes and selectively connecting to an external device.
The jig according to claim 16 or 17.