JP4071859B2 - Sensor calibration method in seismic observation equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seismometer calibration (sensitivity test) method in an earthquake observation apparatus equipped with a multi-channel earthquake measurement system.
[0002]
[Prior art]
Seismometers called strong seismometers are used mainly for the purpose of obtaining seismic response records of structures (buildings, dams, etc.) during strong earthquakes.
This strong seismometer is activated when an earthquake larger than a preset magnitude is detected, and a servo accelerometer is used as the sensor.
[0003]
The servo accelerometer that constitutes the sensor is equipped with a test coil for the accelerometer, and an external calibration signal (test signal) (usually a sine waveform current of several Hz to several tens Hz). ) To move the sensor, and the accelerometer is verified from the sensor movement at that time.
[0004]
By the way, in the case of large structures (large buildings, dams, etc.), as shown in FIG. 2, a large number of sensors 1, 2,..., N are installed in a wide range of structures, that is, in one structure. A multi-channel seismic measurement system A, B, C,..., N is provided to record seismic wave data.
Conventionally, a calibration method for simultaneously calibrating a large number of sensors 1, 2,.
[0005]
That is, in FIG. 2, reference numerals 1, 2, 3,..., N indicate n sensors, respectively, and test coils 1a, 2a,. ing.
[0006]
Reference numeral 5 denotes an oscillator for generating a test signal, and a test signal (waveform is indicated by reference numeral 4) generated by the oscillator 5 is supplied to each of the test coils 1a to na as current amplifiers 11, 12,. And it is transmitted via change-over switches 21, 22, ..., 2n. The changeover switches 21, 22,..., 2n are normally set to OFF.
Reference numeral 40 denotes a CPU that controls the oscillator 5 and the change-over switches 21, 22,..., 2n.
[0007]
The CPU 40 simultaneously transmits an “oscillator ON” signal and a signal “energizes each changeover switch 21, 22,..., 2n to ON”. A test signal is sent to each of the test coils 1a to na.
Reference numeral 50 denotes a starter that instructs the CPU 40 to generate the signal.
[0008]
If a program for instructing the signal generation is incorporated in the CPU 40 every predetermined time (for example, every 24 hours or every month), the sensor (accelerometer) can be periodically tested. The installation of the starter 50 can be omitted when the starter 50 is configured by the software of the CPU 40 from the data of the A / D converter. The test signal ends in about 60 seconds, for example.
Reference numerals 61, 62,..., 6n denote amplifiers, and reference numeral 70 denotes an A / D converter.
[0009]
The current amplifier 11, the changeover switch 21, the test coil 1a, and the amplifier 61 are connected in series to constitute a calibration first channel earthquake measurement system A (hereinafter abbreviated as "first channel A"). The second channel B, the third channel C... The nth channel N are configured.
[0010]
When the oscillator 5 is actuated by a command of the CPU 40 and a test signal is sent to each of the test coils 1a to na, the signals of the test coils 1a to na according to the test signal are caught by the sensors 1 to n, and the signal is sent to each amplifier. 61 to 6n, the A / D data line 80 is returned to the CPU 40 via the A / D converter 70, whereby each sensor is calibrated.
Reference numeral 90 indicates a start pulse line.
[0011]
[Problems to be solved by the invention]
In the conventional calibration method described above, calibration is performed simultaneously for all sensors. Therefore, even if an earthquake occurs during calibration, there is a problem that the sensor is in a calibration stage and cannot record seismic wave data.
The present invention is intended to solve such a problem. The calibration is performed for the remaining channels except for a specific channel, and in the time zone after the calibration is completed, the channel which has not been calibrated last time is corrected. An object of the present invention is to provide a method for calibrating a sensor in a seismic observation apparatus that performs calibration.
[0012]
[Means for Solving the Problems]
In the seismic observation apparatus having a multi-channel seismic measurement system, the present invention calibrates the sensors of the remaining channels of the seismic measurement system except for the seismic measurement system of a specific channel. In the method of performing calibration of the sensor of the seismic measurement system of the specific channel that was not previously calibrated in the time zone after the end of the calibration, the other channel of the seismic measurement system of the channel being calibrated When the earthquake measurement system detects an earthquake, the earthquake measurement system of the channel being calibrated is immediately shifted to the seismic wave data recording mode to solve the problem.
[0013]
According to the calibration method of the present invention, an earthquake observation apparatus having a multi-channel earthquake measurement system can continuously detect the occurrence of earthquakes and record seismic wave data even when the sensor is calibrated.
[0014]
In addition, when an occurrence of an earthquake is detected, all channels can be switched to a seismic wave data recording mode, and an alarm can be generated as necessary. Therefore, it is possible to continuously observe an earthquake that does not know when it occurs.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a sensor calibration method in an earthquake observation apparatus as an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram thereof.
In FIG. 1, the same reference numerals as those in FIG. 2 indicate substantially the same members.
[0016]
The seismic observation apparatus of this embodiment also has a multi-channel seismic measurement system including n strong motion meters having sensors 1 to n, and test coils 1a to na are attached to the sensors 1 to n, respectively. ing.
[0017]
Further, a CPU 40, a starter 50, an oscillator 5, and current amplifiers 11 to 1n are provided, and the channels other than the Nth channel (the first, second, and third channels in the example shown in FIG. 1) are described above. The sensor is calibrated in the same procedure as the conventional method.
[0018]
In the case of this embodiment, the CPU 40 generates a command signal so as to calibrate the N-th channel sensor in a time zone after the calibration of each sensor of the first to third channels A, B, and C is completed. The program is stored.
[0019]
That is, in the time zone after the calibration of the sensors of the first to third channels A, B, and C is completed, the oscillator 40 is operated, and at the same time, a signal for setting the changeover switch 2n to ON is output from the CPU 40. Only the sensor of the Nth channel is calibrated.
[0020]
Therefore, even if an earthquake occurs during calibration of a channel outside the Nth channel, it is detected on the Nth channel. In addition, the earthquake during calibration of the Nth channel is detected by other channels (first to third channels). Further, when these earthquake occurrence detection signals are transmitted to the CPU 40 through the amplifiers 61 to 63 or 6n, the A / D converter 70 and the data line 80, the calibration of the channels being calibrated is stopped and all the channels are informed of the seismic wave data. A program for shifting to the recording mode is also stored in the CPU 40.
[0021]
As described above, the sensor is calibrated for the remaining channels except for a specific channel (the Nth channel in this example), and only the sensor of the Nth channel is calibrated in the time zone after the calibration is completed. As a result, the occurrence of an earthquake can be detected continuously, and once an earthquake is detected, calibration can be stopped and all channels can be switched to the seismic data recording mode, so it is not known when it will occur. Earthquakes can be recorded continuously.
[0022]
In addition, when a circuit that activates an alarm at the same time as detecting the occurrence of an earthquake is attached, the installation effect of the seismic observation device is further improved.
[0023]
【The invention's effect】
As described above in detail, according to the present invention, the following effects can be obtained.
(1) An earthquake observation device equipped with a multi-channel seismic measurement system can continuously detect the occurrence of earthquakes and record seismic wave data even during sensor calibration.
(2) When an occurrence of an earthquake is detected, all channels can be switched to the seismic data recording mode, and an alarm can be generated as necessary, so it is possible to continuously observe earthquakes that do not know when they occur. .
[Brief description of the drawings]
FIG. 1 is a block diagram showing a sensor calibration method in an earthquake observation apparatus as one embodiment of the present invention.
FIG. 2 is a block diagram showing a sensor calibration method in a conventional seismic observation apparatus.
[Explanation of symbols]
1, 2, 3, ..., n sensor 1a, 2a, 3a, ..., na Test coil 4 Test signal (waveform)
5 Oscillator
11, 12, 13,…, 1n current amplifier
21, 22, 23, 2n selector switch
40 CPU
50 starter
61, 62, 63,…, 6n amplifier
70 A / D converter
80 Data line A First seismic measurement system B Second seismic measurement system C Third seismic measurement system N Nth seismic measurement system

Claims (1)

In a seismic observation system equipped with a multi-channel seismic measurement system, the sensor calibration is performed on the seismic measurement system of the remaining channels except for the seismic measurement system of a specific channel of the multi-channel seismic measurement system. In the method of calibrating the sensor of the seismic measurement system of the specific channel that was not previously calibrated in the time zone after the completion of the earthquake , the seismic measurement system of the channel outside the seismic measurement system of the channel being calibrated A method for calibrating a sensor in an earthquake observation apparatus, wherein when an earthquake is detected, the seismic measurement system of the channel being calibrated is immediately shifted to a seismic data recording mode .

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