JP7724093B2 - Ground movement detection device - Google Patents

Description

The present invention relates to a ground movement detection device , and more particularly to a ground movement detection device capable of detecting underground ground movement.

Ground deformation such as landslides and debris flows can cause a variety of disasters, so it is important to detect their signs early. When ground deformation occurs, various phenomena occur underground.

For example, the ground movement measurement device described in Patent Document 1 installs a subsidence element, which is a magnetic generator, in a measurement hole drilled in the ground, installs multiple magnetic sensors on the inner wall of the hole retention pipe, and extracts an electrical signal corresponding to the relative displacement between the subsidence element and the magnetic sensor to detect changes in the subsidence element, thereby detecting subsidence and uplift of the ground layer.

The ground movement detection system described in Patent Document 2 installs ground movement monitoring devices equipped with IC tags and vibration detection sensors on the ground surface, receives signals from each ground movement monitoring device using a reading device (IC tag reader), and determines the occurrence of cliff collapses, debris flows, landslides, etc. when specified vibrations are detected.

Japanese Patent Application Publication No. 3-152420 JP 2009-47534 A

When ground deformation such as landslides or debris flows occurs, it is believed that the ground moves horizontally underground before the ground surface slides. The invention described in Patent Document 1 above can detect vertical ground movement (subsidence and uplift), but cannot detect horizontal movement underground.

Furthermore, while the invention described in Patent Document 2 can detect vibrations caused by underground ground movement, it is difficult to determine whether the vibrations are causing ground movement such as landslides or debris flows. Furthermore, the installation of reading devices, power sources, etc. is expensive.

The present invention was devised in view of the above problems, and aims to provide a ground movement detection device that can detect the phenomenon of horizontal movement of the ground underground with a simple configuration.

According to the present invention, there is provided a ground movement detection device comprising: a cylindrical body buried vertically in the ground and capable of deforming horizontally due to ground movement; a rope inserted under tension within the cylindrical body; and tension detection means for detecting fluctuations in the tension of the rope ; wherein the tension detection means comprises a protective box installed on the ground surface; a movable body placed within the protective box and movable by the tension of the rope; and output means for outputting the amount of movement of the movable body to the outside; and the output means comprises a display board placed on the surface of the movable body; and an opening formed in the protective box through which part of the display board can be seen from the outside; the display board is colored so that the colors differ in the vertical direction, and fluctuations in the tension of the rope can be seen from the opening by changing the color of the display board.

The cylindrical body may be composed of an assembly of multiple stacked short tubes.

The cord may be connected to an anchor located at the lower end of the cylindrical body.

Only the cord may be inserted inside the cylindrical body.

According to the ground movement detection device of the present invention described above, it is possible to detect the phenomenon of horizontal movement of the ground with a simple configuration in which a cylindrical body that can deform horizontally due to ground movement is buried in the ground and a cable is inserted under tension through the cylindrical body.

1 is a partial cross-sectional view showing the overall configuration of a ground movement detection device according to an embodiment of the present invention. 2A to 2C are explanatory diagrams showing the operation of the output means shown in FIG. 1, where (A) shows a safety stage, (B) shows a caution stage, and (C) shows a danger stage. 1A and 1B are explanatory diagrams showing a ground movement detection method according to an embodiment of the present invention, in which (A) shows an initial state and (B) shows a detected state. 10A and 10B are explanatory diagrams showing a first modified example of the extension force detection means, in which FIG. 10A shows the initial state and FIG. 10B shows the detection state. 10A and 10B are explanatory diagrams showing other modified examples of the tension detection means, in which (A) shows a second modified example and (B) shows a third modified example.

Embodiments of the present invention will be described below using Figures 1 to 5(B). Here, Figure 1 is a partial cross-sectional view showing the overall configuration of a ground movement detection device according to one embodiment of the present invention. Figure 2 is an explanatory diagram showing the operation of the output means shown in Figure 1, with (A) indicating the safety stage, (B) indicating the caution stage, and (C) indicating the danger stage.

As shown in Figures 1 and 2, a ground movement detection device 1 according to one embodiment of the present invention comprises a cylindrical body 2 that is buried vertically in the ground G and is capable of deforming horizontally due to ground movement, a rope 3 that is inserted under tension within the cylindrical body 2, and a tension detection means 4 that detects changes in the tension of the rope 3. Note that Figure 1 omits portions of the intermediate portions of the cylindrical body 2 and the rope 3.

The cylindrical body 2 is composed, for example, of an assembly of multiple stacked short tubes 21. Each short tube 21 has a cylindrical shape made of resin and a height of, for example, 10 to 100 cm. The multiple short tubes 21 are aligned vertically to form a single cylindrical body 2 that is several meters to approximately 10 meters long. Because the short tubes 21 are stacked at their end faces, they are configured to be easily bendable and move horizontally at the stacked portion when a horizontal force is applied.

A plate-shaped anchor 22 with a diameter larger than that of the cylindrical body 2 is disposed at the lower end of the cylindrical body 2. The anchor 22 may include an anchor bolt 23 with a ring-shaped portion to which the rope body 3 can be connected.

Note that the cylindrical body 2 is not limited to the configuration shown in the figure and may be a single tube. Furthermore, the multiple short pipes 21 may have different heights depending on the depth of the ground G to which they are buried.

The rope 3 is, for example, a wire rope. The rope 3 may be made of metal or resin as long as it has a predetermined load capacity. The upper end of the rope 3 is connected to the tension detection means 4, the lower end of the rope 3 is connected to the anchor bolt 23, and the middle portion of the rope 3 is inserted into the inside of the cylindrical body 2 while being maintained in a tensioned state.

The tension detection means 4 includes, for example, a protective box 41 installed on the ground surface, a moving body 42 placed inside the protective box 41 and movable by the tension of the rope 3, and an output means 43 that outputs the amount of movement of the moving body 42 to the outside.

The protective box 41 comprises a box body 41a that houses the moving body 42 and legs 41b that are installed underground G. An elastic body 44 is arranged on the upper inner surface of the box body 41a, which generates resistance when the moving body 42 is pulled downward by the rope 3. The elastic body 44 is, for example, a spring member. The elastic force of the elastic body 44 can be used to adjust the amount of movement of the moving body 42.

In addition, a guide member for guiding the movement of the moving body 42 may be arranged on the inner side surface of the box body 41a. Furthermore, the legs 41b may be fixed to a foundation installed underground G.

The movable body 42 is a box or block that is movably housed in the protective box 41. The output means 43 includes a display board 45 placed on the surface of the movable body 42 and an opening 46 formed in the protective box 41 through which part of the display board 45 can be seen from the outside.

As shown in Figure 2(A), the display panel 45 is formed so that the colors vary from top to bottom. For example, the bottom row is blue, the middle row is yellow, and the top row is red. For ease of explanation, the protective box 41 (box) is shown with dotted lines in each of Figures 2(A) to 2(C).

Figure 2 (A) shows the initial state, a safety stage where no horizontal ground movement has occurred. At this time, the lower part of the display board 45 is set at the position of the opening 46 so that it can be seen from outside.

Figure 2 (B) shows the caution stage, in which horizontal ground movement begins and the moving body 42 is pulled downward by the tension of the cable 3. At this time, the middle section of the display board 45 becomes visible from the outside at the position of the opening 46.

Figure 2 (C) shows a danger level where horizontal ground movement has increased and there is a possibility that ground movement such as a landslide or debris flow may occur in the near future. At this time, the moving body 42 is pulled further downward by the tension of the cable 3, and the upper part of the display board 45 becomes visible from the outside at the position of the opening 46.

In this embodiment, the output means 43 is described as displaying fluctuations in the tension of the rope 3 through changes in color, but it is also possible to display fluctuations in the tension of the rope 3 using light or sound.

Next, a ground movement detection method according to one embodiment of the present invention will be described with reference to Figures 1 to 3(B). Here, Figure 3 is an explanatory diagram showing a ground movement detection method according to one embodiment of the present invention, with (A) showing the initial state and (B) showing the detected state.

The ground movement detection devices 1 shown in Figure 1 are installed at predetermined intervals along a slope, for example, as shown in Figure 3 (A). The ground movement detection devices 1 are arranged, for example, linearly from the top to the bottom of the slope. Note that multiple ground movement detection devices 1 may also be installed in a distributed manner over a portion of the slope.

The ground movement detection method according to this embodiment involves installing a cylindrical body 2 that is buried vertically underground G and is capable of deforming horizontally due to ground movement, inserting a cable 3 under tension through the cylindrical body 2, and detecting changes in the tension of the cable 3 to detect horizontal ground movement.

The cylindrical body 2 and the rope 3 are inserted into a vertical hole excavated in the ground G and buried in the ground G. As shown in Figures 1 and 3(A), in the initial state, the cylindrical body 2 and the rope 3 are installed in a state extending vertically.

After that, as the ground moves horizontally, as shown by the arrow in Figure 3(B), the cylindrical body 2 deforms and curves overall in response to the ground movement. The deformation of the cylindrical body 2 generates tension in the rope 3, and as shown in Figures 2(B) and 2(C), the moving body 42 moves downward. As the moving body 42 moves, the color of the display board 45 visible through the opening 46 changes, making it easy to check the level of danger from outside.

The ground movement detection device 1 and ground movement detection method according to the present embodiment described above can detect horizontal ground movement with a simple configuration in which a cylindrical body 2 that can deform horizontally due to ground movement is buried underground G, and a cable body 3 is inserted under tension through the cylindrical body 2.

Next, modified examples of the tension detection means 4 will be described with reference to Figures 4(A) to 5(B). Here, Figure 4 is an explanatory diagram showing a first modified example of the tension detection means, with (A) showing the initial state and (B) showing the detected state. Figure 5 is an explanatory diagram showing another modified example of the tension detection means, with (A) showing a second modified example and (B) showing a third modified example.

In the first modified example shown in Figures 4(A) and 4(B), the elastic body 44 is configured as a damper. The damper may be a hydraulic damper or an air damper. The output means 43 may also be an alarm device that lights up a warning light or sounds an alarm in response to pressure fluctuations within the damper.

For example, as shown in Figure 4(B), when the cable 3 is pulled downward due to horizontal movement of the ground, the moving body 42 moves downward, and when a predetermined pressure is generated within the damper, the output means 43 is activated.

In the modified example shown in Figures 5(A) and 5(B), the output means 43 is configured to be able to communicate with the main body of the tension detection means 4, and is installed in a location separate from the main body of the tension detection means 4. The output means 43 may be a warning light or alarm device, or a display or monitor that displays fluctuations in the tension of the rope 3 on a screen.

The second variant shown in Figure 5(A) places the output means 43 near the road R, for example. By separating the output means 43 from the main body, people can easily be notified of horizontal movement of the ground, even if a place where people may be present is far from the slope.

In the third variant shown in Figure 5 (B), the output means 43 is configured as a mobile terminal such as a computer or smartphone installed within the facility. In this case, since the output means 43 may be installed in a location separate from the main body of the tension detection means 4 or may be mobile, it is connected to the main body via a repeater 47 such as a radar or artificial satellite.

The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

REFERENCE SIGNS LIST 1 Ground movement detection device 2 Cylinder 3 Rope 4 Tension detection means 21 Short pipe 22 Anchor 23 Anchor bolt 41 Protective box 41a Box 41b Leg 42 Moving body 43 Output means 44 Elastic body 45 Display board 46 Opening 47 Repeater G Underground R Road

Claims (4)

a cylindrical body that is buried vertically in the ground and is capable of deforming horizontally due to ground movement;
A cord that is inserted in a tensioned state into the cylindrical body;
and a tension detection means for detecting a change in tension of the rope body,
the tension detection means comprises a protective box installed on the ground surface, a movable body disposed in the protective box and movable by the tension of the rope body, and an output means for outputting the amount of movement of the movable body to the outside,
the output means includes a display board disposed on a surface of the moving body, and an opening formed in the protective box through which a part of the display board can be seen from the outside,
The display plate is colored differently in the vertical direction, and the change in the color of the display plate makes it possible to visually recognize the change in tension of the rope body through the opening.
A ground movement detection device characterized by: The ground movement detection device described in claim 1, wherein the cylindrical body is composed of an assembly of multiple stacked short tubes. The ground movement detection device described in claim 1, wherein the cable is connected to an anchor located at the lower end of the cylindrical body. The ground movement detection device according to claim 1 , wherein only the cable is inserted inside the cylindrical body.