JP4006732B2 - Ground displacement detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a disaster prevention landslide prediction system for the purpose of protecting human life from landslides, such as detecting the displacement of the ground, which is a precursor of landslides, at an early stage and monitoring it in a safe place and issuing an alarm when necessary. The present invention relates to a ground displacement detection apparatus according to the present invention.
[0002]
[Prior art]
Conventional landslide warning devices are mainly composed of linear members and reference piles, and the structure is fixed to slopes by placing fixed nails in places of linear members and linear members extending downward from the reference piles. When the landslide occurs, the fixed nail falls down and is caught by the linear member, and the linear member is pulled by the movement of the landslide to detect the occurrence of the landslide (for example, see Patent Document 1). This type of device is a mechanism for issuing an alarm for the first time after a landslide has occurred, and has a drawback in that there is no time to evacuate after issuing the alarm. Moreover, a general extensometer is an observation at one point, and there is a problem that it cannot be installed on an infinite number of general dangerous slopes.
[Patent Document 1]
Japanese Patent Laid-Open No. 11-160173
[Problems to be solved by the invention]
There are a myriad of steeply dangerous places in Japan, and many damages are caused by heavy rain every year. It is common sense that landslide prediction must be monitored in real time on countless slopes in a wide area, and the location and time must be identified. It is one of the most important technical fields.
[0004]
When steep slopes such as cliffs become unstable due to heavy rain, local shear failure progresses inside the ground. In the process, fine cracks are initially generated on the ground surface, and over time, the shear fracture gradually progresses and the cracks expand. Eventually, the crack reaches several tens of centimeters, and when the local shear breaking progresses beyond a certain level, the stability of the ground is greatly impaired, and the entire slope is collapsed at once. Therefore, if such initial crack expansion can be monitored, the occurrence of landslides can be predicted.
[0005]
[Means for Solving the Problems]
In the present invention, the above-described problems are solved by a simple apparatus that employs an observation method that uses an iron ball for ground displacement detection and information transmission. That is, when the ground is displaced, a number of iron balls 7 corresponding to the amount of ground displacement are dropped from the iron ball storage case 6 to the main body pipe 2, and the iron balls 7 discharged through the movable pipe 4 are freely passed through the detection pipe 8 . This is a method of falling and reaching the observation-side iron ball storage case 9 . As a result, the ground displacement detection device 1 of the present invention does not use electricity, and the pipe is used for both the sensor and the iron ball transport tool, and the structure is simple, so that the maintenance management becomes easy.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
In the ground displacement detection device 1 of the present invention , a slit 3 is provided in the upper length direction of a main body pipe 2 having a diameter of 20 to 50 mm, and an iron ball storage case 6 is provided so as to cover the slit 3. Then, the movable pipe 4 is inserted so as to close the slit 3 from the inside . At the time of installation, an iron ball is loaded following the slit 3 and set in the iron ball storage case 6 .
[0007]
At this time, the iron ball 7 is in a state of being vertically arranged on the slit 3 closed from the inside by the movable pipe 4, and the upper end of the apparatus is fixed to the stationary ground together with the fixed pipe 5, and the other end is fixed . The movable pipe 4 is fixed by a pipe fixing pile 10 to the moving ground below through the detection pipe 8. In accordance with the movement of the moving ground, the movable pipe 4 leaves the socket-type ground displacement detection device fixed to the non-moving ground.
[0008]
The iron ball 7 on the slit provided in the socket-type ground detection device loses its support in order from the upper side and falls into the main body pipe 2 when the movable pipe 4 comes off. The dropped iron balls 7 pass through the inside of the movable pipe 4, are further carried downward by gravity through the inside of the detection pipe 8 , and are arranged in the observation side iron ball storage case 9 in the order of dropping.
[0009]
As shown in FIG. 4, the ground displacement detection device 1 detects ground displacement for predicting landslides by using one or more according to the length of the slope. The ground displacement detection device 1 is fixed by hitting a pipe fixing pile 10 on a landslide risk slope. Then, the ground displacement detection devices 1 are connected by a detection pipe 8 . When the ground displacement detection device 1 is used continuously, the detection pipe 8 is connected to the movable pipe 4 of the upper ground displacement detection device 1 and to the fixed pipe 5 of the lower ground displacement detection device 1. That is, when the specific ground displacement detection device 1 is used as a reference, the fixed pipe 5 is connected to the upper ground displacement detection device 1 through the detection pipe 8 and the socket, and is connected to the ground displacement detection device 1 by the socket. Absorb. The movable pipe 4 is connected to the fixed pipe 5 via the detection pipe 8 with respect to the next lower detection device, and the pipe is always continuously connected to the observation-side iron ball storage case 9. The detection pipe 8 is fixed to the ground at some places with guide piles 11 . For this reason, the pipe moves up and down along the slope, but does not shift laterally.
[0010]
All the iron balls dropped from any part of the ground displacement detection device are carried to the observation-side iron ball storage case 9 provided in a private house at the lower end of the slope. The ground displacement amount is determined by the total number of diameters of the iron balls 7 that have reached the observation-side iron ball storage case 9, and the degree of progress of the deformation is determined by the frequency of the iron balls 7 falling into the observation-side iron ball storage case 9. It is possible to know the position of occurrence of ground displacement by attaching numbers and colors to the iron balls 7 separately.
[0011]
【The invention's effect】
If the landslide prediction system using the ground displacement detection device of the present invention is used , direct information on the cliff deformation of each house can be obtained, so that residents can be freed from fear of landslides. In addition, if a deformation occurs, the degree and progress of the deformation can be easily grasped, so it is possible to evacuate at an appropriate time, and the safety of residents is enhanced in the house where this landslide prediction device is installed. .
[0012]
When the ground displacement detection device of the present invention is installed, even if it does not collapse, it becomes an important document for subsequent countermeasures when the deformation is confirmed. However, it is also possible to carry out countermeasure work, and it is possible to proceed with more effective countermeasures for steep slopes in today's financial difficulties. If it is used in landslides, road disaster locations, and road hazard locations, it will contribute to improving safety.
[Brief description of the drawings]
FIG. 1 is a front view of a ground displacement detection device.
FIG. 2 is a side view of the ground displacement detection device.
FIG. 3 is a cross-sectional view of a ground displacement detection device.
FIG. 4 is an explanatory diagram showing an arrangement of a ground displacement detection device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ground displacement detector 2 Main body pipe 3 Slit 4 Movable pipe 5 Fixed pipe
6 Iron ball storage case 7 Iron ball
8 Detection pipe
9 Observation-side iron ball storage case
10 Pile for fixing pipes
11 Guide pile
12 Sliding surface

Claims (1)

A main pipe with a diameter of 20 to 50 mm has a slit with a width that allows an iron ball with a diameter of 5 to 20 mm to pass through, and an iron ball storage case that can store the iron balls on top of the slit. A fixed pipe for connection is installed on the bottom, and a socket-type movable pipe that can be moved in accordance with the extension displacement of the ground is installed on the lower side. A socket-type ground displacement that drops into the main pipe, passes through the inside of the movable pipe and discharges it outside the device, and detects the ground displacement based on the number and interval of the discharged iron balls. Detection device.

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