JP2011232119A - Landslide measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to measure the amount of moved clod of landslide at landslide surface without leading wire onto ground.SOLUTION: A landslide measurement device includes a measurement device 10 for measuring the amount of movement of clod 200 of landslide at a landslide surface 250, a transmitting antenna coil 21 for transmitting data with a low-frequency magnetic field, a control device 23 for receiving measurement data from the measurement device and transmitting the measurement data by using the transmitting antenna coil, a battery 25 for supplying electric power to the measurement device, the transmitting antenna coil and the control device, and a box 30 containing the measurement device, the transmitting antenna coil, the control device and the battery and embedded in the ground such that it intersects the boundary surface.

Description

  The present invention relates to a landslide measuring apparatus that measures shear deformation or the like in the ground using a borehole.

  The boundary surface between a landslide mass that moves due to a landslide and the non-moving foundation ground is usually called a slip surface. To measure the amount of landslide mass movement on the slip surface, a wire with one end fixed to a certain depth in the ground is led to the ground through a borehole, and the amount of extension (feeding amount) of the wire is measured with a measuring device installed on the ground. An underground extensometer is used (Non-patent Document 1).

"Landslide Observation Manual", pages 164 to 167, issued by the Japan Landslide Countermeasure Technology Association, October 1996

  However, the following problems have been pointed out in the underground extensometer.

  1. Measurement equipment installed on the ground may be displaced due to the settlement of the landslide mass, and the amount of landslide movement may not be evaluated properly.

  2. Before the movement of the landslide mass due to landslide begins, contact between the hole wall and the wire due to bending or crushing of the borehole, or wire breakage may occur, resulting in measurement error or measurement itself becoming impossible. .

  The present invention is intended to provide a landslide measuring apparatus that can solve the above-mentioned problems.

  In order to solve the above problems, the present invention provides a measuring instrument that measures the amount of movement of a landslide lump accompanying a landslide in the immediate vicinity of a slip surface, and a data collection and transmission unit that collects the measured data and wirelessly transmits it to the ground. It is characterized by being buried inside.

  Specifically, according to the aspect of the present invention, the interface between the landslide mass and the non-moving foundation ground, that is, a measuring instrument that measures the amount of movement of the landslide mass on the landslide surface, and transmits data using a low-frequency magnetic field. A transmission antenna coil, a control device that receives measurement data from the measuring instrument and transmits the measurement data through the transmission antenna coil, a battery that supplies power to the measuring instrument, the transmission antenna coil, and the control device, and the measurement A landslide measuring device comprising: a storage device, a transmitting antenna coil, a control device, and a battery, and a housing embedded in the ground in a state of passing through the boundary surface.

  The landslide measuring apparatus according to the above aspect includes an A / D converter that converts the measurement data from the measuring instrument into digital data, and the control apparatus stores the digital data in an attached memory and determines in advance. It is desirable to transmit by the transmission antenna coil at the transmission timing.

  As another aspect of the present invention, the above-mentioned landslide measuring apparatus, a receiving apparatus that includes a receiving antenna coil that receives a signal due to a low-frequency magnetic field from the transmitting antenna coil, and that extracts the measurement data from the received signal of the receiving antenna coil; A landslide measuring system characterized by comprising:

  According to the present invention, it is possible to measure the amount of movement of the landslide mass on the landslide surface without leading the wire to the ground.

  Further, according to the present invention, since the wire is accommodated in the housing, there is no problem that the wire is disconnected before the movement of the landslide mass by the landslide starts.

It is a schematic sectional drawing for demonstrating the installation form of the landslide measuring apparatus by this invention. It is the figure which expanded the landslide measuring apparatus shown in FIG. 1, and showed schematic structure. It is a block diagram for demonstrating the structural example of the data collection transmission part in the landslide measuring apparatus by this invention.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view for explaining an installation mode of a landslide measuring apparatus according to the present invention. In the present embodiment, in order to install the landslide measuring device 1 in the ground that requires measurement, the borehole 100 is formed by boring or the like, and the landslide measuring device 1 is inserted from the ground and fixed at a predetermined depth. . The depth of the boring hole 100 reaches the foundation ground 300 through the boundary surface between the landslide block 200 and the foundation ground 300 that does not move even if there is a landslide, that is, the landslide surface 250. The reason will be described later.

  In order to position and fix the landslide measuring apparatus 1 in the boring hole 100, the boring hole 100 is filled with a grout 400 such as cement bentonite and solidified.

  FIG. 2 is a diagram showing a schematic configuration of the landslide measuring apparatus 1 according to the embodiment of the present invention. The landslide measuring device 1 includes a measuring instrument 10 that measures the amount of movement of the landslide mass 200, a data collection transmission unit 20 that collects measurement data from the measuring instrument 10, and transmits the collected measurement data to the ground wirelessly. These are accommodated in a cylindrical housing 30 having an upper surface and a bottom surface. The housing 30 is made of a material such as a vinyl chloride pipe.

  The measuring instrument 10 uses the operation principle of Non-Patent Document 1, but the configuration itself is different. That is, the measuring instrument 10 according to the present embodiment includes a wire 11, a fixing portion 12, and a measuring portion 13, and one end side of the wire 11, here, the upper end side is fixed to the fixing portion 12, while the other end side (lower end side). In the measuring unit 13), the wire 11 can be fed out by a configuration like a thread winding reel, and the feeding amount of the wire 11 is measured from the rotation amount of the reel. The measuring unit 13 uses the same principle as that of a volume controller using a variable resistor, for example, to measure the amount of the wire 11 that is fed out, and an electric signal whose level changes in accordance with the amount of feeding of the wire 11 (the amount of rotation of the take-up reel). And output as measurement data.

  In order to detect the movement of the landslide mass 200 as a change in the feeding amount of the wire 11, the measuring instrument 10 is arranged so that the landslide surface 250 is between the fixed part 12 and the measuring part 13, in other words, the wire 11 is landslide. It needs to be installed over the surface 250. The depth of the boring hole 100 is determined in consideration of this, considering the depth of the landslide surface 250, the length size of the landslide measuring device 1, and the like.

  In any case, according to the measuring instrument 10 as described above, the displacement of the landslide surface, that is, the movement amount of the landslide lump 200 can be measured without leading the wire 11 to the ground.

  Moreover, since the boring hole 100 is filled with the grout 400 or the like and the wire 11 is accommodated in the housing 30, the hole 11 is not crushed and the wire 11 is not broken before a landslide occurs.

  FIG. 3 is a block diagram illustrating a schematic configuration of the data collection / transmission unit 20 in the landslide measuring apparatus 1.

  Here, the data collection and transmission unit 20 is converted into a transmission antenna coil 21 for transmitting data in a low-frequency magnetic field, and an A / D converter 22 that converts measurement data from the measurement unit 13 into digital data. The control device 23 for transmitting the received digital data by the transmission antenna coil 21, the memory 24 for temporarily storing the digital data, the measuring unit 13, the transmission antenna coil 21, the A / D converter 22, the control device 23, and the memory 24 And a battery 25 for supplying. Although not shown, these components are preferably housed in a case separate from the housing 30.

  The control device 23 can be realized by a means such as a microcomputer chip, for example. The transmission antenna coil 21 is excited with power from the battery 25 and the excitation is controlled to generate a low frequency magnetic field signal. The digital data from the A / D converter 22 or the digital data read from the memory 24 is superimposed on the low frequency magnetic field signal and transmitted. The low-frequency magnetic field signal can be transmitted not only in the ground but also in water.

  The transmission of digital data by the transmission antenna coil 21 may be continuous, but it is preferable to perform intermittent transmission at regular intervals in consideration of the saving effect of the battery 25. For this reason, the digital data from the A / D converter 22 is stored in the memory 24. However, the memory 24 is not necessary as long as raw data can be collected at a constant period.

  Returning to FIG. 1, the low-frequency magnetic field signal transmitted from the transmission antenna coil 21 is received by the reception antenna coil 40 installed on the ground. On the ground side, a receiving device (not shown) that includes a receiving antenna coil 40 and extracts digital data from a received signal of the receiving antenna coil 40 is installed. In addition to the receiving antenna coil 40, the receiving device includes control means for processing the extracted digital data and display output means for displaying or printing out the processed data. The receiving device may also have a function of generating an alarm when the processed data (movement amount of the landslide block 200) is compared with a preset threshold and the threshold is exceeded. The control means and the display output means are preferably installed in a separate place away from the receiving antenna coil 40 where no landslide occurs.

  In any case, the receiving device constitutes a landslide measuring system together with the landslide measuring device 1 buried in the ground.

  The landslide measuring apparatus 1 according to the present embodiment is used as follows. First, as described with reference to FIG. 1, a borehole 100 having a depth calculated in advance is formed at a site where landslide measurement is required, and the landslide measuring device 1 is inserted and fixed in the borehole 100. When the landslide measuring apparatus 1 is fixed, the wire 11 is placed on the landslide surface 250 and is fixed by filling and solidifying the grout 400 and the like as described above. In this state, the landslide measuring apparatus 1 is in an operable state, and after converting the measurement data from the measurement unit 13 into digital data, the landslide measurement apparatus 1 periodically transmits the low-frequency magnetic field signal through the transmission antenna coil 21. The receiving device receives the low-frequency magnetic field signal from the transmitting antenna coil 21 through the receiving antenna coil 40 and extracts measurement data.

  The preferred embodiment of the landslide measuring apparatus according to the present invention has been described above, but the present invention is not limited to the above embodiment. For example, the means for detecting the feeding amount of the wire 11 in the measuring unit 13 of the measuring instrument 10 is not limited to the one using the principle of the volume controller, and various other known means can be used. Further, the configuration of the data collection / transmission unit 20 shown in FIG. 3 is merely an example, and any configuration may be used as long as the measurement data from the measurement unit 13 is transmitted as a low-frequency magnetic field signal using the transmission antenna coil 21. It may be. Further, a transmission antenna coil for transmitting an operation command with a low-frequency magnetic field signal is provided on the receiving device side, while a reception antenna coil for receiving the operation command is provided on the data collection / transmission unit 20 side, so that a landslide measurement operation is performed. Can be performed by an operation command from the ground side. Needless to say, the frequency of the low-frequency magnetic field in this case is distinguished from the frequency for measurement data transmission. In addition, when the landslide measuring device is installed at a plurality of locations that are not so far away from each other, ID (identification information) may be added to the measurement data.

DESCRIPTION OF SYMBOLS 1 Landslide measuring device 10 Measuring instrument 11 Wire 12 Fixed part 13 Measuring part 20 Data collection transmission part 30 Case 40 Receiving antenna coil 400 Grout

Claims (4)

  A measuring instrument that measures the amount of movement of the landslide mass associated with the landslide in the immediate vicinity of the boundary surface between the landslide mass and the stationary ground, that is, the landslide surface, and a data collection and transmission unit that collects the measured data and transmits it to the ground wirelessly Landslide measuring device characterized by burying in the ground. A measuring instrument that measures the amount of movement of the landslide mass at the boundary surface between the landslide mass and the stationary ground, that is, the landslide surface;
A transmitting antenna coil for transmitting data in a low frequency magnetic field;
A control device for receiving measurement data from the measuring instrument and transmitting the measurement data by the transmission antenna coil;
A battery for supplying power to the measuring instrument, the transmitting antenna coil, and the control device;
Housing the measuring instrument, transmission antenna coil, control device, battery, and a case embedded in the ground in a state passing through the boundary surface;
A landslide measuring device characterized by comprising: An A / D converter for converting measurement data from the measuring instrument into digital data;
The landslide measuring apparatus according to claim 2, wherein the control device stores the digital data in an attached memory and transmits the digital data by the transmission antenna coil at a predetermined transmission timing. The landslide measuring device according to claim 2 or 3,
A receiving device for receiving a signal by a low-frequency magnetic field from the transmitting antenna coil, and a receiving device for extracting the measurement data from the received signal of the receiving antenna coil;
A landslide measurement system characterized by comprising:

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