JP2020183955A - Monitoring device and soundness monitoring system - Google Patents

Abstract

To provide a monitoring device and a soundness monitoring system which can precisely evaluate soundness of at least one of a bridge pier, a foundation of the bridge pier, and ground of the foundation.SOLUTION: A monitoring device 100 includes: an acceleration sensor 111 for measuring microtremor of a bridge pier at a predetermined frequency; a spectrum analyzer 1121 for analyzing a spectrum of vibration frequencies of the bridge pier on the basis of measurement data by the acceleration sensor 111; a frequency distribution aggregator 1122 for obtaining a frequency distribution by aggregating the vibration frequencies with the largest amplitude among a predetermined frequency band in a predetermined period on the basis of analysis result by the spectrum analyzer 1121; and a dominant frequency calculator 1123 for calculating a dominant frequency of the bridge pier on the basis of aggregation result by the frequency distribution aggregator 1122.SELECTED DRAWING: Figure 2

Description

The present invention relates to a monitoring device and a soundness monitoring system.

In general, it is known that in bridges hung on rivers and the like, the soundness of the stability of piers deteriorates due to local scouring and lowering of the riverbed. Therefore, in recent years, a new method for evaluating the soundness of a pier by measuring the constant tremor of the pier due to wind or water flow has been studied (for example, Patent Document 1).

In Patent Document 1, the constant tremor of the pier is measured by an acceleration sensor, and the power spectrum area ratio that correlates with the natural frequency of the pier is calculated from the measured value of the constant tremor. Then, the amount of overburden is estimated based on the power spectrum area ratio to evaluate the soundness of the pier.

JP-A-2017-3417

However, in Patent Document 1, the measurement data of the acceleration sensor includes the influence of environmental noise. Specifically, since the structural characteristics of the pier, such as strength, load, and binding force, change with temperature changes, the constant tremor of the pier is affected by the ambient air temperature. The constant tremor of the pier is also affected by the water level of the river where the pier is installed. Furthermore, environmental factors such as temperature and water level fluctuate depending on the season and sudden meteorological phenomena. Therefore, there is a problem that the power spectrum area ratio that correlates with the natural frequency of the pier cannot be calculated accurately, and the soundness of the pier may not be evaluated properly.

An object of the present invention is to provide a monitoring device and a soundness monitoring system capable of appropriately evaluating the soundness of at least one of a pier, a foundation of a pier, and the ground of the foundation.

The monitoring device of the present invention is a monitoring device installed on a pier and measuring the soundness of at least one of the pier, the foundation of the pier, and the ground of the foundation, and measures the constant tremor of the pier at a predetermined frequency. Based on the acceleration sensor, the spectrum analysis unit that analyzes the spectrum of the vibration frequency of the pier based on the measurement data of the acceleration sensor, and the analysis result by the spectrum analysis unit, in a predetermined frequency band in a predetermined period. It is provided with a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude, and a dominant frequency calculation unit that calculates the dominant frequency of the pier based on the aggregation result by the frequency distribution aggregation unit. It is a feature.

In the present invention, the spectrum analysis unit analyzes the spectrum of the vibration frequency of the pier. Then, based on the analysis result, the frequency distribution aggregation unit aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in the predetermined period. Then, the predominant frequency calculation unit calculates the predominant frequency of the pier based on the frequency distribution of the vibration frequency. That is, the dominant frequency calculation unit does not directly calculate the dominant frequency from the vibration frequency spectrum of the bridge pedestal, but calculates the dominant frequency based on the frequency distribution in which the vibration frequency spectrum is statistically aggregated. ..
Here, since the change in the spectrum due to environmental noise or the like is irregular and not constant, the frequency is low. On the other hand, the change in the spectrum due to the natural vibration is regular and constant, so the frequency is high. Therefore, by calculating the predominant frequency based on the frequency distribution of the spectrum of the vibration frequency, the influence of environmental noise and the like can be reduced. Therefore, the predominant frequency can be calculated accurately, and the soundness of at least one of the pier, the foundation of the pier, and the ground of the foundation can be properly evaluated.

In the monitoring device of the present invention, it is preferable that the dominant frequency calculation unit calculates the vibration frequency of the average value of the frequency distribution as the dominant frequency.
In this configuration, the dominant frequency calculation unit calculates the vibration frequency of the average value of the frequency distribution as the dominant frequency, so that the dominant frequency can be calculated accurately.

In the monitoring device of the present invention, it is preferable that the dominant frequency calculation unit calculates the median vibration frequency of the frequency distribution as the dominant frequency.
In this configuration, the dominant frequency calculation unit calculates the vibration frequency of the median value of the frequency distribution as the dominant frequency, so that the dominant frequency can be calculated accurately.

In the monitoring device of the present invention, it is preferable that the dominant frequency calculation unit calculates the most frequent vibration frequency of the frequency distribution as the dominant frequency.
In this configuration, the dominant frequency calculation unit calculates the most frequent vibration frequency of the frequency distribution as the dominant frequency, so that the dominant frequency can be calculated accurately.

The monitoring device of the present invention may include a storage unit that stores the dominant frequency calculated by the dominant frequency calculation unit and an output unit that outputs the dominant frequency stored in the storage unit. preferable.
In this configuration, the output unit appropriately outputs the dominant frequency stored in the storage unit to the outside. That is, since the monitoring device outputs the dominant frequency, which is the calculation result, instead of the raw data obtained by constantly measuring the fine movement, the amount of data transmitted is small. Therefore, the time required for data transmission can be shortened.

The monitoring device of the present invention includes a power supply unit that supplies electric power, and the electric power supply unit includes a solar panel that generates electric power, a storage battery that stores electric power generated by the solar panel, and the storage battery. It is preferable to include a switching unit for switching between the power supply and the power supply from the solar panel.
In this configuration, the acceleration sensor and the like can be operated by using the electric power generated by the solar panel. Further, the surplus electric power generated by the solar panel is sent to the storage battery, and when the solar panel cannot generate electricity such as at night, the switching unit can output the electric power from the storage battery to the acceleration sensor or the like. Therefore, a battery such as a dry battery can be eliminated, and the frequency of use can be reduced, so that the labor and cost of battery replacement can be reduced.

The soundness monitoring system of the present invention is a soundness monitoring system that monitors at least one soundness of a pier, a foundation of the pier, and the ground of the foundation, and is a monitoring device installed on the pier and the monitoring device. The monitoring device includes an acceleration sensor that measures the constant tremor of the pier at a predetermined frequency, and the vibration frequency of the pier based on the measurement data of the acceleration sensor. A spectrum analysis unit that analyzes the spectrum of the above, a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period based on the analysis result by the spectrum analysis unit, and the above-mentioned A predominant frequency calculation unit that calculates the predominant frequency of the pier based on the aggregation result by the frequency distribution totaling unit, a storage unit that stores the predominant frequency calculated by the predominant frequency calculation unit, and the storage. The soundness evaluation device includes an output unit that outputs the dominant frequency stored in the unit, and the soundness evaluation device acquires the dominant frequency output from the monitoring device and the acquisition unit. It is characterized by including an evaluation unit for evaluating at least one soundness of the pier, the foundation of the pier, and the ground of the foundation based on the predominant frequency.
In the present invention, the same effect as described above can be obtained.

The soundness monitoring system of the present invention is a soundness monitoring system that monitors at least one soundness of a pier, a foundation of the pier, and the ground of the foundation, and is a monitoring device installed on the pier and the monitoring device. The monitoring device includes an acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency, and the vibration frequency of the pier based on the measurement data of the acceleration sensor. The soundness evaluation device includes a spectrum analysis unit that analyzes the spectrum of the above, a storage unit that stores the analysis result by the spectrum analysis unit, and an output unit that outputs the analysis result stored in the storage unit. Based on the acquisition unit that acquires the analysis result output from the monitoring device and the analysis result acquired by the acquisition unit, the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period is determined. To the dominant frequency calculation unit that calculates the dominant frequency of the pier based on the aggregation result by the frequency distribution totaling unit and the dominant frequency calculation unit, and the dominant frequency calculated by the dominant frequency calculation unit. Based on this, it is characterized by including an evaluation unit for evaluating at least one soundness of the pier, the foundation of the pier, and the ground of the foundation.
In the present invention, the same effect as described above can be obtained.
Further, since the soundness evaluation device includes a frequency distribution totaling unit and an outstanding frequency calculation unit, the configuration of the monitoring device can be simplified as compared with the case where the monitoring device includes these.

The soundness monitoring system of the present invention is a soundness monitoring system that monitors at least one soundness of a pier, a foundation of the pier, and the ground of the foundation, and is a monitoring device installed on the pier and the monitoring device. The monitoring device includes an acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency, and the vibration frequency of the pier based on the measurement data of the acceleration sensor. A spectrum analysis unit that analyzes the spectrum of the above, a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period based on the analysis result by the spectrum analysis unit, and the above-mentioned A predominant frequency calculation unit that calculates the predominant frequency of the pier based on the aggregation result by the frequency distribution totaling unit, a storage unit that stores the predominant frequency calculated by the predominant frequency calculation unit, and the storage. The soundness evaluation device includes an output unit that outputs the superior frequency stored in the unit, and the soundness evaluation device includes the superior frequency of the pier and at least one of the pier, the foundation of the pier, and the ground of the foundation. A learning unit that learns the soundness as teacher data, an acquisition unit that acquires the dominant frequency output from the monitoring device, the dominant frequency acquired by the acquisition unit, and a learning result by the learning unit. Based on the above, the pier, the foundation of the pier, and an evaluation unit for evaluating at least one soundness of the ground of the foundation are provided.
In the present invention, the same effect as described above can be obtained.
Further, in the present invention, the soundness evaluation device includes a learning unit that learns the predominant frequency of the pier and at least one soundness of the pier, the foundation of the pier and the ground of the foundation as teacher data, and the predominant frequency. It is provided with an evaluation unit that evaluates the soundness of at least one of the pier, the foundation of the pier, and the ground of the foundation based on the learning result by the learning unit. As a result, the accuracy of estimating the soundness based on the predominant frequency can be improved, so that the soundness of at least one of the pier, the foundation of the pier, and the ground of the foundation can be evaluated more accurately.

The soundness monitoring system of the present invention is a soundness monitoring system that monitors at least one soundness of a pier, a foundation of the pier, and the ground of the foundation, and is a monitoring device installed on the pier and the monitoring device. The monitoring device includes an acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency, and the vibration frequency of the pier based on the measurement data of the acceleration sensor. The soundness evaluation device includes a spectrum analysis unit that analyzes the spectrum of the above, a storage unit that stores the analysis result by the spectrum analysis unit, and an output unit that outputs the analysis result stored in the storage unit. Based on the acquisition unit that acquires the analysis result output from the monitoring device and the analysis result acquired by the acquisition unit, the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period is determined. The frequency distribution aggregation unit to be aggregated, the dominant frequency calculation unit that calculates the dominant frequency of the pier based on the aggregation result by the frequency distribution aggregation unit, the dominant frequency of the pier, the pier, and the pier. Based on the learning unit that learns the foundation and at least one soundness of the ground of the foundation as teacher data, the dominant frequency calculated by the dominant frequency calculation unit, and the learning result by the learning unit. It is characterized by including an evaluation unit for evaluating at least one soundness of the pier, the foundation of the pier, and the ground of the foundation.
In the present invention, the same effect as described above can be obtained.
Further, in the present invention, the soundness evaluation device includes a learning unit that learns the predominant frequency of the pier and at least one soundness of the pier, the foundation of the pier and the ground of the foundation as teacher data, and the predominant frequency. It is provided with an evaluation unit that evaluates the soundness of at least one of the pier, the foundation of the pier, and the ground of the foundation based on the learning result by the learning unit. As a result, the accuracy of estimating the soundness based on the predominant frequency can be improved, so that the soundness of at least one of the pier, the foundation of the pier, and the ground of the foundation can be evaluated more accurately.

The schematic diagram which shows the schematic structure of the soundness monitoring system which concerns on 1st Embodiment of this invention. The block diagram which shows the schematic structure of the monitoring apparatus of 1st Embodiment. The block diagram which shows the schematic structure of the soundness evaluation apparatus of 1st Embodiment. A flowchart illustrating a soundness monitoring method. The figure which shows an example of the spectrum analysis result. The figure which shows an example of the aggregation result of a frequency distribution. The figure which shows an example of the relationship between the predominant frequency and the measured value of soil cover amount. The figure which shows an example of the relationship between the soil cover amount estimated value based on the predominant frequency, and the soil cover amount actual measurement value. The figure which shows the schematic structure of the monitoring apparatus of 2nd Embodiment. The figure which shows the schematic structure of the soundness evaluation apparatus of 2nd Embodiment. The figure which shows the schematic structure of the soundness evaluation apparatus of 3rd Embodiment. The figure which shows the schematic structure of the soundness evaluation apparatus of 4th Embodiment.

[First Embodiment]
The first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of the soundness monitoring system 1 of the first embodiment.
As shown in FIG. 1, the soundness monitoring system 1 according to the present embodiment monitors the soundness of the pier BP of the bridge B hung on the river R.
The pier BP supports the bridge girder BG, and the bridge girder BG is provided with roads and railroad tracks for people and vehicles to pass through.

The soundness monitoring system 1 includes a monitoring device 100 installed on the pier BP and a soundness evaluation device 200.
The monitoring device 100 includes a measuring unit 110 and a solar panel 120. The measuring unit 110 is installed at an arbitrary position on the upper portion of the pier BP in order to measure the constant fine movement of the pier BP. The solar panel 120 may be installed at a position where it can receive sunlight, and is installed, for example, on a street lamp pole LP on the bridge girder BG.
The soundness evaluation device 200 is configured as, for example, a portable device (for example, a smartphone, a tablet terminal, etc.) that can be carried by a bridge inspector.

[Monitoring device 100]
FIG. 2 is a block diagram showing a schematic configuration of the monitoring device 100.
As shown in FIG. 2, the measurement unit 110 includes an acceleration sensor 111, a control unit 112, a storage unit 113, a communication unit 114, a storage battery 115, a backup battery 116, and a switching unit 117. In the present embodiment, these are unitized by being housed in one case. That is, the measurement unit 110 is a smart sensor in which each function is integrated.

The solar panel 120 receives sunlight and converts the energy of the received sunlight into electric power.
The storage battery 115 is a secondary battery capable of storing surplus electric power among the electric power generated by the solar panel 120.
The backup battery 116 is, for example, a primary battery such as a button battery or a dry battery.
The switching unit 117 is selectively connected to the power source of any one of the solar panel 120, the storage battery 115, and the backup battery 116, and is also connected to the acceleration sensor 111, the control unit 112, the storage unit 113, and the communication unit 114. There is.
Note that FIG. 2 schematically shows a power line connecting each block. Further, a DC-DC converter (not shown) for stabilizing the DC voltage is connected between the power sources of the solar panel 120, the storage battery 115, and the backup battery 116 and the switching unit 117.

In this embodiment, the solar panel 120, the storage battery 115, the backup battery 116, and the switching unit 117 constitute a power supply unit 130 for supplying electric power to the acceleration sensor 111, the control unit 112, and the like.
For example, the switching unit 117 selects the solar panel 120 as the connection destination when the solar panel 120 is sufficiently generating power. Further, when the solar panel 120 cannot generate electricity such as at night, the switching unit 117 switches the connection destination to the storage battery 115. Further, when the power supply from the solar panel 120 and the storage battery 115 is insufficient with respect to the power consumption of the acceleration sensor 111 and the control unit 112, the switching unit 117 switches the connection destination to the backup battery 116.
As such a switching unit 117, an electronic switch (diode switch) that preferentially switches to the one having the supply capacity can be used.

The acceleration sensor 111 measures the acceleration (vibration information) of constant tremor in the direction orthogonal to the axial direction of the bridge girder BG (direction orthogonal to the bridge axis) at a predetermined frequency. The constant tremor is a minute vibration that constantly occurs in the pier BP due to the influence of wind or water flow, for example. The reason for measuring the constant tremor in the direction orthogonal to the bridge axis is that it is more affected by scouring.
As the acceleration sensor 111, a highly accurate 3-axis accelerometer capable of detecting minute vibrations, such as a MEMS accelerometer, is used. By using a MEMS accelerometer, it can be driven at low cost and with low power consumption.
The acceleration sensor 111 is not limited to the use of a 3-axis accelerometer, and for example, a 1-axis accelerometer may be used.

The control unit 112 is composed of a CPU (Central processing unit), a memory, and the like, and executes processing by the CPU executing a program stored in the memory.
The control unit 112 includes a spectrum analysis unit 1121, a frequency distribution aggregation unit 1122, and a dominant frequency calculation unit 1123.
The spectrum analysis unit 1121 analyzes the spectrum of the vibration frequency of the pier BP based on the measurement data of the acceleration sensor 111.
The frequency distribution aggregation unit 1122 aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period based on the analysis result of the spectrum analysis unit 1121.
The predominant frequency calculation unit 1123 calculates the predominant frequency N of the pier BP based on the aggregation result by the frequency distribution aggregation unit 1122.
The details of the spectrum analysis unit 1121, the frequency distribution aggregation unit 1122, and the predominant frequency calculation unit 1123 will be described later.

The storage unit 113 is composed of a RAM (Random Access Memory), a non-volatile memory such as an SD card, and the like, and cumulatively stores the dominant frequency N in association with a predetermined period.
The communication unit 114 is a communication interface that mediates wireless communication (for example, Blue tooth (registered trademark), Wi-Fi (registered trademark), etc.) as an output unit including wireless communication means, and is, for example, from the soundness evaluation device 200. In response to the request of, the data including the dominant frequency N stored in the storage unit 113 up to that point is output. The communication unit 114 is an example of the output unit of the present invention.

[Soundness Evaluation Device 200]
FIG. 3 is a block diagram showing a schematic configuration of the soundness evaluation device 200.
As shown in FIG. 3, the soundness evaluation device 200 includes a communication unit 210, a control unit 220, and a database 230.
The communication unit 210 is a communication interface that mediates wireless communication, and acquires analysis data including the dominant frequency N from the monitoring device 100. The communication unit 210 is an example of the acquisition unit of the present invention.

The control unit 220 is composed of a CPU, a memory, and the like, and the CPU executes each process by executing a program stored in the memory. The control unit 220 has an evaluation unit 2201.
The evaluation unit 2201 evaluates the soundness of the pier BP by comparing the dominant frequency N with the preset reference value D as an index of soundness.
The database 230 stores the predominant frequency N analyzed in the past, the reference value D for soundness evaluation supported by the past results, and the like for the pier BP of the bridge B.

[Health monitoring method]
Next, the soundness monitoring method of the present embodiment will be described with reference to the flowchart of FIG.
As shown in FIG. 4, first, as step S1, the acceleration sensor 111 measures the constant fine movement of the pier BP once a day as a predetermined frequency at a measurement time set by a timer or the like, and measures the measurement. Get the data. One measurement is performed multiple times (for example, 5 times) at predetermined intervals (for example, 30 minutes) in the middle of the night when there is little traffic of the vehicle, and one measurement time is, for example, a dozen seconds. Is. That is, one constant fine movement measurement by the acceleration sensor 111 is configured by a plurality of measurements at predetermined intervals.
The measurement frequency of the acceleration sensor 111 is not limited to once a day, and may be, for example, once every 12 hours, and can be set arbitrarily.

Next, as step S2, the spectrum analysis unit 1121 analyzes the spectrum of the vibration frequency of the pier BP.
FIG. 5 is a diagram showing an example of the spectrum analysis result by the spectrum analysis unit 1121.
As shown in FIG. 5, the spectrum analysis unit 1121 analyzes the waveform of the time change of the acceleration in the measurement time by a known method, and shows the magnitude of the vibration for each vibration frequency as the amplitude, so that the vibration of the bridge leg BP Analyze the frequency spectrum.

Next, as step S3, the frequency distribution aggregation unit 1122 aggregates the frequency distribution.
FIG. 6 is a diagram showing an example of the aggregation result of the frequency distribution by the frequency distribution aggregation unit 1122.
As shown in FIG. 6, the frequency distribution totaling unit 1122 totals the frequency of the vibration frequency for each class value. In this embodiment, the width of each class is 0.05 Hz. For example, in the example shown in FIG. 5, the vibration frequency having the largest amplitude is 3.41 Hz, which is 3.375 or more and less than 3.425. Therefore, the frequency is counted as a class value of 3.40 Hz.
Here, in the present embodiment, the frequency distribution totaling unit 1122 obtains the frequency distribution of the vibration frequency having the largest amplitude among the frequencies of 2.50 Hz to 5.00 Hz as the predetermined frequency band in one month as the predetermined period. Tally.
The predetermined period is not limited to one month, and may be, for example, two weeks, and can be arbitrarily set. Further, the predetermined frequency band is not limited to 2.50 Hz to 5.00 Hz, and may be, for example, 0.00 Hz to 10.00 Hz, and can be arbitrarily set according to the characteristics of the pier BP.

Next, in step S4, the dominant frequency calculation unit 1123 calculates the dominant frequency N of the pier BP. In the present embodiment, the dominant frequency calculation unit 1123 calculates the vibration frequency of the average value of the frequency distribution as the dominant frequency N. Specifically, the predominant frequency calculation unit 1123 calculates the average value of the frequency distribution by integrating the value obtained by multiplying each class value by each frequency and dividing the value by the integrated value of each class value. calculate. Then, the dominant frequency calculation unit 1123 stores the calculated dominant frequency N in the storage unit 113 in association with the date and time of the predetermined period. For example, when the dominant frequency calculation unit 1123 calculates the dominant frequency N based on the frequency distribution aggregated during the period from April 1st to April 30th, April 1st, which is the first date of the period. The dominant frequency N is stored in the storage unit 113A in association with the above. Note that the dominant frequency calculation unit 1123 is not limited to storing the dominant frequency N calculated in association with the first date of the period. For example, the predominant frequency calculation unit 1123 may store the calculated predominant frequency N in association with the intermediate day of the period, or may store it in association with the period from April 1st to April 30th. Good.

Next, as step S5, the communication unit 114 outputs the dominant frequency N stored in the storage unit 113 to the soundness evaluation device 200. In the present embodiment, for example, when a bridge inspector carries the soundness evaluation device 200 and enters the wireless communication range with the monitoring device 100 and performs a data request operation, the communication unit 210 of the soundness evaluation device 200 is set. Output the data request signal. Then, the communication unit 114 of the monitoring device 100 receives the data request signal, and outputs the data including the dominant frequency N to the soundness evaluation device 200 based on the data request signal. As a result, the communication unit 210 of the soundness evaluation device 200 acquires the dominant frequency N.
The communication unit 114 of the monitoring device 100 and the communication unit 210 of the soundness evaluation device 200 are not limited to those configured as described above. For example, the communication unit 114 of the monitoring device 100 and the communication unit 210 of the soundness evaluation device 200 may be configured to be communicable via an internet line or the like. With this configuration, even if the bridge inspector carries the soundness evaluation device 200 and does not enter the wireless communication range with the monitoring device 100, the data including the dominant frequency N is acquired from the monitoring device 100. be able to.

Finally, as step S6, the evaluation unit 2201 of the soundness evaluation device 200 evaluates the soundness of the pier BP.
FIG. 7 is a diagram showing an example of the relationship between the predominant frequency N of the pier BP and the measured overburden amount HM.
The database 230 stores in advance the relationship between the predominant frequency N shown in FIG. 7 and the measured overburden value HM, which was obtained by the preliminary survey. Then, the evaluation unit 2201 calculates the overburden amount estimated value HE from the relationship between the predominant frequency N shown in FIG. 7 and the overburden amount actual measurement value HM, and stores the overburden amount estimated value HE in the database 230.

FIG. 8 shows the estimated overburden amount HE and the overburden amount based on the predominant frequency N when the pier BP of the bridge B is monitored using the soundness monitoring system 1 of the present embodiment for about two years. It is a figure which shows an example of the relationship with the measured value HM. The amount of overburden was actually measured by a known echo sounding method.
As shown in FIG. 8, in the present embodiment, the soil cover amount was actually measured four times during the monitoring period of about two years, and the soil cover amount actual measurement value HM was estimated from the predominant frequency N. The value was equivalent to the overburden amount estimated value HE. That is, it was clarified that the amount of overburden of the pier BP can be estimated with high accuracy from the calculated dominant frequency N.
Then, the evaluation unit 2201 compares the reference value D stored in the database 230 with the overburden amount estimated value HE to evaluate the soundness of the pier BP. That is, if the overburden amount estimated value HE is larger than the reference value D, the evaluation unit 2201 evaluates it as sound. On the other hand, when the overburden amount estimated value HE is less than the reference value D, the evaluation unit 2201 evaluates it as abnormal. Then, when the evaluation unit 2201 evaluates as abnormal, it issues an alarm such as an alarm sound or a warning display by an alarm device (not shown) or the like. According to this, detailed inspection and repair can be performed by a shock vibration test or the like.

In the first embodiment as described above, the following effects can be obtained.
(1) In the present embodiment, the spectrum analysis unit 1121 analyzes the spectrum of the vibration frequency of the pier BP. Then, based on the analysis result, the frequency distribution aggregation unit 1122 aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band of 2.50 Hz to 5.00 Hz in one month, which is a predetermined period. Then, the dominant frequency calculation unit 1123 calculates the dominant frequency N of the pier BP based on the frequency distribution of the vibration frequency. That is, the dominant frequency calculation unit 1123 does not directly calculate the dominant frequency N from the vibration frequency spectrum of the bridge pier BP, but the dominant frequency is based on the frequency distribution in which the vibration frequency spectrum is statistically aggregated. Calculate N.
Here, since the change in the spectrum due to environmental noise or the like is irregular and not constant, the frequency is low. On the other hand, the change in the spectrum due to the natural vibration is regular and constant, so the frequency is high. Therefore, the influence of environmental noise and the like can be reduced by calculating the dominant frequency N based on the frequency distribution of the vibration frequency spectrum. Therefore, the predominant frequency N can be calculated accurately, and the soundness of the pier BP can be properly evaluated.

(2) In the present embodiment, the dominant frequency calculation unit 1123 calculates the vibration frequency of the average value of the frequency distribution as the dominant frequency N. Therefore, the dominant frequency calculation unit 1123 can accurately calculate the dominant frequency N.

(3) In the present embodiment, the communication unit 114 appropriately outputs the dominant frequency N stored in the storage unit 113 in response to the data request signal from the communication unit 210 of the soundness evaluation device 200. That is, since the monitoring device 100 outputs the predominant frequency N, which is the calculation result, instead of the raw data obtained by constantly measuring the fine movement, the amount of data transmitted is reduced. Therefore, the time required for data transmission can be shortened.

(4) In the present embodiment, the acceleration sensor 111 and the like can be operated by using the electric power generated by the solar panel 120. Further, of the electric power generated by the solar panel 120, the surplus electric power is sent to the storage battery 115, and when the solar panel 120 cannot generate electric power such as at night, the switching unit 117 transfers the electric power from the storage battery 115 to the acceleration sensor 111 or the like. Can be output. Therefore, since the frequency of use of the backup battery 116 can be reduced, the labor and cost of replacing the backup battery 116 can be reduced.

[Second Embodiment]
Next, the second embodiment of the present invention will be described with reference to the drawings.
The second embodiment is different from the first embodiment in that the soundness evaluation device 200A is provided with the frequency distribution totaling unit 2202A and the predominant frequency calculation unit 2203A. In the second embodiment, the same or similar configurations as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

[Monitoring device 100A]
FIG. 9 is a block diagram showing a schematic configuration of the monitoring device 100A.
As shown in FIG. 9, the monitoring device 100A includes a control unit 112A, a storage unit 113A, and a communication unit 114A.
The control unit 112A includes a spectrum analysis unit 1121A.

The storage unit 113A stores the analysis result by the spectrum analysis unit 1121A.
Then, the communication unit 114A outputs the analysis result stored in the storage unit 113A to the soundness evaluation device 200A.

[Soundness evaluation device 200A]
FIG. 10 is a block diagram showing a schematic configuration of the soundness evaluation device 200A.
As shown in FIG. 10, the soundness evaluation device 200A includes a communication unit 210A, a control unit 220A, and a database 230A. The control unit 220A includes an evaluation unit 2201A, a frequency distribution aggregation unit 2202A, and a predominant frequency calculation unit 2203A.
The communication unit 210A is configured as a communication interface that mediates wireless communication, and acquires the analysis result by the spectrum analysis unit 1121A from the monitoring device 100A.

The frequency distribution aggregation unit 2202A aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period based on the analysis result acquired by the communication unit 210A.
The predominant frequency calculation unit 2203A calculates the predominant frequency N of the pier BP based on the aggregation result by the frequency distribution aggregation unit 2202A.
The configurations of the frequency distribution aggregation unit 2202A and the predominant frequency calculation unit 2203A are the same as the configurations of the frequency distribution aggregation unit 1122 and the predominant frequency calculation unit 1123 of the first embodiment described above.

In the second embodiment as described above, the following effects can be obtained.
(5) In the present embodiment, the soundness evaluation device 200A includes a frequency distribution aggregation unit 2202A and a predominant frequency calculation unit 2203A. As a result, the configuration of the monitoring device 100A can be simplified as compared with the case where the monitoring device 100 includes the frequency distribution totaling unit 1122 and the dominant frequency calculation unit 1123 as in the first embodiment described above.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to the drawings.
The third embodiment is different from the first and second embodiments in that the learning unit 2204B is provided in the soundness evaluation device 200B. In the third embodiment, the same or similar configurations as those in the first and second embodiments are designated by the same reference numerals, and the description thereof will be omitted.

[Soundness evaluation device 200B]
FIG. 11 is a block diagram showing a schematic configuration of the soundness evaluation device 200B.
As shown in FIG. 11, the soundness evaluation device 200B includes a communication unit 210B, a control unit 220B, and a database 230B. The control unit 220B includes an evaluation unit 2201B and a learning unit 2204B. The communication unit 210B has the same configuration as the communication unit 210 of the first embodiment described above.

[Learning unit 2204B]
The learning unit 2204B performs supervised machine learning based on a so-called neural network. In the present embodiment, the learning unit 2204B uses, for example, the measured value HM (healthness) of the overburden amount of the pier BP measured by the echo sounding method and the dominant frequency N acquired via the communication unit 210B as teacher data. Perform machine learning.
Specifically, the neural network constituting the learning unit 2204B has an input layer, an intermediate layer, and an output layer, each of which is composed of a plurality of neurons. Then, machine learning is performed so that the overburden amount estimated value HE output from the output layer approaches the overburden amount actual measurement value HM based on the dominant frequency N input to the input layer. As shown in FIG. 7, a correlation is observed between the predominant frequency N and the measured overburden value HM.
Further, the trained model learned by the learning unit 2204B is stored in the database 230B. The trained model by the learning unit 2204B is stored in the database 230B prior to the evaluation of the soundness by the evaluation unit 2201B, but even if the trained model is updated at any time while being evaluated by the evaluation unit 2201B. Good.

[Evaluation unit 2201B]
The evaluation unit 2201B evaluates the soundness of the pier BP based on the dominant frequency N acquired via the communication unit 210B and the learning result (learned model) by the learning unit 2204B.
Specifically, the evaluation unit 2201B acquires the dominant frequency N via the communication unit 210B. Then, the evaluation unit 2201B acquires the overburden amount estimated value HE by inputting the acquired dominant frequency N into the trained model stored in the database 230B. After that, the evaluation unit 2201B compares the reference value D stored in the database 230B with the overburden amount estimated value HE to evaluate the soundness of the pier BP.

In the third embodiment as described above, the following effects can be obtained.
(6) In the present embodiment, the soundness evaluation device 200B is a pier based on the learning results of the learning unit 2204B and the learning unit 2204B, which learn the dominant frequency N of the pier BP and the measured value HM of the overburden amount as teacher data. It is provided with an evaluation unit 2201B for evaluating the soundness of the BP. As a result, the estimation accuracy of the overburden amount estimated value HE based on the predominant frequency N can be improved, so that the soundness of the pier BP can be evaluated more accurately.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to the drawings.
The fourth embodiment is different from the first and second embodiments in that the learning unit 2204C is provided in the soundness evaluation device 200C as in the third embodiment described above. In the fourth embodiment, the same or similar configurations as those in the first to third embodiments are designated by the same reference numerals, and the description thereof will be omitted.

[Soundness evaluation device 200C]
FIG. 12 is a block diagram showing a schematic configuration of the soundness evaluation device 200C.
As shown in FIG. 12, the soundness evaluation device 200C includes a communication unit 210C, a control unit 220C, and a database 230C. The control unit 220C includes an evaluation unit 2201C, a frequency distribution aggregation unit 2202C, a dominant frequency calculation unit 2203C, and a learning unit 2204C. The communication unit 210C, the frequency distribution totaling unit 2202C, and the dominant frequency calculation unit 2203C are configured as the communication unit 210A, the frequency distribution totalization unit 2202A, and the dominant frequency calculation unit 2203A of the second embodiment described above, respectively. Is similar to.

[Learning unit 2204C]
The learning unit 2204C performs supervised machine learning based on a so-called neural network, similarly to the learning unit 2204B of the third embodiment described above. In the present embodiment, the learning unit 2204C uses the measured value HM (healthness) of the overburden amount of the pier BP measured by the echo sounding method and the dominant frequency N calculated by the dominant frequency calculation unit 2203C as teacher data. Do learning. Then, the trained model learned by the learning unit 2204C is stored in the database 230C.

[Evaluation unit 2201C]
The evaluation unit 2201C evaluates the soundness of the pier BP based on the dominant frequency N calculated by the dominant frequency calculation unit 2203C and the learning result (learned model) by the learning unit 2204C.
Specifically, the evaluation unit 2201C acquires the dominant frequency N calculated by the dominant frequency calculation unit 2203C. Then, the evaluation unit 2201C acquires the overburden amount estimated value HE by inputting the acquired dominant frequency N into the trained model stored in the database 230C. After that, the evaluation unit 2201C compares the reference value D stored in the database 230C with the overburden amount estimated value HE to evaluate the soundness of the pier BP.

In the fourth embodiment as described above, the following effects can be achieved.
(7) In the present embodiment, similarly to the third embodiment described above, the soundness evaluation device 200C includes a learning unit 2204C that learns the superior frequency N of the pier BP and the measured overburden amount HM as teacher data. It is provided with an evaluation unit 2201C that evaluates the soundness of the pier BP based on the learning result by the learning unit 2204C. Therefore, as in the third embodiment described above, the soundness of the pier BP can be evaluated more accurately.

[Modification example]
The present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the range in which the object of the present invention can be achieved are included in the present invention.
In each of the above-described embodiments, the monitoring devices 100 and 100A are configured to be capable of measuring the soundness of the pier BP of the bridge B hung on the river R, but the present invention is not limited to this. For example, the monitoring devices 100 and 100A may be configured to be able to measure the soundness of the foundation F of the pier BP and the ground G of the foundation F, and measure the soundness of at least one of the pier BP, the foundation F and the ground G. It suffices if it is configured to be possible. That is, the soundness monitoring system 1 may be configured to be able to monitor at least one soundness of the pier BP, the foundation F, and the ground G.

In each of the above embodiments, the monitoring devices 100 and 100A are provided on one pier BP, but the present invention is not limited to this. For example, the monitoring devices 100 and 100A may be provided on a plurality of pier BPs. Further, monitoring devices 100 and 100A as controls for temperature compensation may be provided on the pier BP provided on land. In this case, the calculation result of the dominant frequency N by the monitoring devices 100, 100A installed on the pier BP in the river R is calculated based on the calculation result of the dominant frequency N by the monitoring devices 100, 100A installed on the pier BP on the land. The temperature can be corrected.

In each of the above-described embodiments, the dominant frequency calculation units 1123, 2203A, 2203C are configured to calculate the vibration frequency of the average value of the frequency distribution as the dominant frequency N, but the present invention is not limited to this. For example, the dominant frequency calculation units 1123, 2203A, 2203C calculate the frequency of the median value of the frequency distribution as the dominant frequency N, or calculate the frequency of the most frequent value of the frequency distribution as the dominant frequency N. It may be configured as follows. Even with such a configuration, the dominant frequency N can be calculated with high accuracy.

In each of the above-described embodiments, the monitoring devices 100 and 100A include communication units 114 and 114A as output units, but the present invention is not limited thereto. For example, the monitoring devices 100 and 100A may have a data writing unit for writing data including the dominant frequency N to a recording medium instead of the communication units 114 and 114A. In this case, the soundness evaluation devices 200, 200A, 200B, 200C have a reading unit that reads data including the dominant frequency N from the recording medium instead of the communication units 210, 210A, 210B, 210C as the acquisition unit. You may be.

In each of the above embodiments, the soundness evaluation devices 200, 200A, 200B, and 200C are configured as portable devices such as smartphones and tablet terminals, but the present invention is not limited to this, and for example, as a stationary device. It may be configured.
Further, the soundness evaluation devices 200, 200A, 200B, 200C may be incorporated in the monitoring devices 100, 100A. That is, it may be configured to send and receive data between the monitoring devices 100 and 100A.

In each of the above embodiments, the measurement units 110 and 110A of the monitoring devices 100 and 100A are unitized, but the present invention is not limited thereto. For example, the communication units 114 and 114A may be installed together with the solar panels 120 and 120A on a streetlight pole LP or the like on the bridge girder BG. Further, the acceleration sensors 111 and 111A are not limited to being housed in the case, and may be directly installed on, for example, the upper surface of the pier BP.

In each of the above embodiments, the power supply units 130 and 130A are configured to include solar panels 120 and 120A, storage batteries 115 and 115A, backup batteries 116 and 116A, and switching units 117 and 117A, but are limited thereto. It's not something. For example, the power supply units 130 and 130A may not include backup batteries 116 and 116A.
Further, the power supply units 130 and 130A may be composed of any one of the solar panels 120 and 120A and the storage batteries 115 and 115A.
Further, the power supply units 130 and 130A may be configured to be able to receive power from the outside of the monitoring devices 100 and 100A. In this case, the power supply units 130 and 130A may not include the solar panels 120 and 120A, the storage batteries 115 and 115A, the backup batteries 116 and 116A, and the switching units 117 and 117A.

In each of the above embodiments, the communication units 114 and 114A of the monitoring devices 100 and 100A are configured as a communication interface that mediates wireless communication, but the present invention is not limited to this, and for example, an interface that mediates wired communication. It may be configured as.
Similarly, the communication units 210, 210A, 210B, 210C of the soundness evaluation devices 200, 200A, 200B, 200C may be configured as an interface that mediates wired communication.

In the above embodiment, the example of the pier BP of the river bridge has been described as the pier BP to be monitored, but the present invention is not limited to this, and for example, the pier of the viaduct may be used. However, in river bridges, the scouring range of the ground G near the pier BP gradually expands, and the stability often deteriorates in the long term, which is particularly suitable for long-term monitoring by applying the present invention.

In the above embodiment, the acceleration sensors 111 and 111A are configured to measure the acceleration of constant tremor in the direction orthogonal to the axial direction of the bridge girder BG (the direction orthogonal to the bridge axis), but the present invention is not limited thereto. .. For example, the acceleration sensors 111 and 111A may be configured to measure the acceleration of the constant tremor in the axial direction of the bridge girder BG, if necessary. Further, the acceleration sensors 111 and 111A may be configured to measure the tilt angle. As a result, the inclination of the pier BP can be measured, so that the monitoring devices 100 and 100A can be configured to output an alarm according to the inclination of the pier BP.

1 ... Soundness monitoring system, 100, 100A ... Monitoring device, 110, 110A ... Measurement unit, 111, 111A ... Acceleration sensor, 112, 112A ... Control unit, 113, 113A ... Storage unit, 114, 114A ... Communication unit (output) Unit), 115, 115A ... Storage battery, 116, 116A ... Backup battery, 117, 117A ... Switching unit, 120, 120A ... Solar panel, 130, 130A ... Power supply unit, 1121, 1121A ... Spectrum analysis unit, 1122, 2202A , 2202C ... Frequency distribution totaling unit, 1123, 2203A, 2203C ... Outstanding frequency calculation unit, 200, 200A, 200B, 200C ... Soundness evaluation device, 210, 210A, 210B, 210C ... Communication unit (acquisition unit), 220, 220A, 220B, 220C ... Control unit, 230, 230A, 230B, 230C ... Database, 2201,201A, 2201B, 2201C ... Evaluation unit, 2204B, 2204C ... Learning unit.

Claims (10)

A monitoring device installed on a pier that measures the health of at least one of the pier, the foundation of the pier, and the ground of the foundation.
An acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency,
A spectrum analysis unit that analyzes the vibration frequency spectrum of the pier based on the measurement data of the acceleration sensor,
Based on the analysis result by the spectrum analysis unit, a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period,
A monitoring device including a predominant frequency calculation unit that calculates the predominant frequency of the pier based on the aggregation result by the frequency distribution totalization unit. In the monitoring device according to claim 1,
The predominant frequency calculation unit is a monitoring device characterized in that the vibration frequency of the average value of the frequency distribution is calculated as the predominant frequency. In the monitoring device according to claim 1,
The dominant frequency calculation unit is a monitoring device characterized in that the vibration frequency of the median value of the frequency distribution is calculated as the dominant frequency. In the monitoring device according to claim 1,
The predominant frequency calculation unit is a monitoring device characterized in that the most frequent vibration frequency of the frequency distribution is calculated as the predominant frequency. In the monitoring device according to any one of claims 1 to 4.
A storage unit that stores the dominant frequency calculated by the dominant frequency calculation unit, and a storage unit that stores the dominant frequency.
A monitoring device including an output unit that outputs the dominant frequency stored in the storage unit. The monitoring device according to any one of claims 1 to 5 includes a power supply unit that supplies power.
The power supply unit
Solar panels that generate electricity and
A storage battery that stores the power generated by the solar panel, and
A monitoring device including a switching unit for switching between power supply from the storage battery and power supply from the solar panel. A health monitoring system that monitors the health of at least one of the pier, the foundation of the pier, and the ground of the foundation.
The monitoring device installed on the pier and
It is equipped with a soundness evaluation device configured to be able to communicate with the monitoring device.
The monitoring device is
An acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency,
A spectrum analysis unit that analyzes the vibration frequency spectrum of the pier based on the measurement data of the acceleration sensor,
Based on the analysis result by the spectrum analysis unit, a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period,
The dominant frequency calculation unit that calculates the dominant frequency of the pier based on the aggregation result by the frequency distribution totalization unit,
A storage unit that stores the dominant frequency calculated by the dominant frequency calculation unit, and a storage unit that stores the dominant frequency.
An output unit for outputting the dominant frequency stored in the storage unit is provided.
The soundness evaluation device is
An acquisition unit that acquires the dominant frequency output from the monitoring device, and
A soundness monitoring system including an evaluation unit for evaluating at least one soundness of the pier, the foundation of the pier, and the ground of the foundation based on the predominant frequency acquired by the acquisition unit. .. A health monitoring system that monitors the health of at least one of the pier, the foundation of the pier, and the ground of the foundation.
The monitoring device installed on the pier and
It is equipped with a soundness evaluation device configured to be able to communicate with the monitoring device.
The monitoring device is
An acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency,
A spectrum analysis unit that analyzes the vibration frequency spectrum of the pier based on the measurement data of the acceleration sensor,
A storage unit that stores the analysis results by the spectrum analysis unit,
It is provided with an output unit that outputs the analysis result stored in the storage unit.
The soundness evaluation device is
An acquisition unit that acquires the analysis result output from the monitoring device, and
Based on the analysis result acquired by the acquisition unit, a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period,
The dominant frequency calculation unit that calculates the dominant frequency of the pier based on the aggregation result by the frequency distribution totalization unit,
A soundness including an evaluation unit for evaluating at least one soundness of the pier, the foundation of the pier, and the ground of the foundation based on the superior frequency calculated by the dominant frequency calculation unit. Degree monitoring system. A health monitoring system that monitors the health of at least one of the pier, the foundation of the pier, and the ground of the foundation.
The monitoring device installed on the pier and
It is equipped with a soundness evaluation device configured to be able to communicate with the monitoring device.
The monitoring device is
An acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency,
A spectrum analysis unit that analyzes the vibration frequency spectrum of the pier based on the measurement data of the acceleration sensor,
Based on the analysis result by the spectrum analysis unit, a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period,
The dominant frequency calculation unit that calculates the dominant frequency of the pier based on the aggregation result by the frequency distribution totalization unit,
A storage unit that stores the dominant frequency calculated by the dominant frequency calculation unit, and a storage unit that stores the dominant frequency.
An output unit for outputting the dominant frequency stored in the storage unit is provided.
The soundness evaluation device is
A learning unit that learns the predominant frequency of the pier and at least one soundness of the pier, the foundation of the pier, and the ground of the foundation as teacher data.
An acquisition unit that acquires the dominant frequency output from the monitoring device, and
An evaluation unit for evaluating at least one soundness of the pier, the foundation of the pier, and the ground of the foundation is provided based on the predominant frequency acquired by the acquisition unit and the learning result by the learning unit. A health monitoring system characterized by this. A health monitoring system that monitors the health of at least one of the pier, the foundation of the pier, and the ground of the foundation.
The monitoring device installed on the pier and
It is equipped with a soundness evaluation device configured to be able to communicate with the monitoring device.
The monitoring device is
An acceleration sensor that measures the constant fine movement of the pier at a predetermined frequency,
A spectrum analysis unit that analyzes the vibration frequency spectrum of the pier based on the measurement data of the acceleration sensor,
A storage unit that stores the analysis results by the spectrum analysis unit,
It is provided with an output unit that outputs the analysis result stored in the storage unit.
The soundness evaluation device is
An acquisition unit that acquires the analysis result output from the monitoring device, and
Based on the analysis result acquired by the acquisition unit, a frequency distribution aggregation unit that aggregates the frequency distribution of the vibration frequency having the largest amplitude in the predetermined frequency band in a predetermined period,
The dominant frequency calculation unit that calculates the dominant frequency of the pier based on the aggregation result by the frequency distribution totalization unit,
A learning unit that learns the predominant frequency of the pier and at least one soundness of the pier, the foundation of the pier, and the ground of the foundation as teacher data.
An evaluation unit that evaluates at least one soundness of the pier, the foundation of the pier, and the ground of the foundation based on the dominant frequency calculated by the dominant frequency calculation unit and the learning result by the learning unit. A health monitoring system characterized by being equipped with.

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