Ground electrical property measuring device

Abstract

To provide an electric characteristics measuring apparatus of a ground which can efficiently measure electric properties of the ground, and facilitates compaction control of a banking.SOLUTION: An electric characteristics measuring apparatus 1 for measuring electric characteristics of a ground includes: a body 2; a penetration probe 3 rotatably pivoted to the body; a penetration device 4 connected to the penetration probe; and a measurement device 5 connected to the body, wherein the penetration probe includes a rod 31 and a penetration member 32, the penetration device is connected to an upper end of the rod, and a sensor part 33 is provided in an intermediate part of the rod.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an apparatus for measuring electrical characteristics of ground, and more particularly to an apparatus for measuring electrical characteristics of ground used for compaction management of embankments. [Background technology]

[0002] Land development is carried out by spreading embankments to a predetermined thickness using a bulldozer or similar tool, and then compacting them with a compaction machine such as a vibratory roller. In this type of land development, the embankment is compacted to a predetermined hardness by performing a number of compactions determined in advance through a compaction test using the compaction machine. However, in actual land development, the soil quality of the embankment is not constant, and the number of compactions required for compaction changes depending on the soil quality.

[0003] On the other hand, conventional methods for determining the hardness of the compaction of the above-mentioned embankment include a method of measuring the density and moisture content of the ground using the radioisotope (RI) method (Patent Document 1), a method of measuring the density of the ground using the sand displacement method (Patent Document 2), and a method of penetrating multiple electrodes into the ground at a predetermined interval on the ground surface, passing a current between any of the electrodes, and calculating the resistivity value from the measured potential difference (Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-206865 [Patent Document 2] Patent No. 5380626 [Patent Document 3] Japanese Patent Application Laid-Open No. 2002-181953 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in compaction management using the radioisotope (RI) method, it is necessary to drill a measurement hole to insert a steel bar that serves as the RI radiation source during measurement, and the RI device itself is heavy, so the measurement work is time-consuming.In addition, compaction management using the sand replacement method is complicated, and the values ​​obtained are prone to human error by the operator.

[0006] Furthermore, compaction management based on resistivity values ​​requires that multiple electrodes be inserted into the ground, and in order to penetrate the hard ground, measurement holes must be drilled in advance for the electrodes to be inserted. In other words, with the above-mentioned conventional method of managing compaction of embankments, it was extremely difficult to efficiently measure any desired location continuously.

[0007] The present invention was made in consideration of the above circumstances, and its objective is to provide a ground electrical property measuring device that can efficiently measure the electrical properties of the ground and easily manage the compaction of embankments. [Means for solving the problem]

[0008] The ground electrical characteristic measuring device of the present invention has been made to solve the above technical problems and has the following features.

[0009] First, the ground electrical characteristic measuring device of the present invention is a measuring device for measuring the electrical characteristics of the ground, The apparatus includes a main body, a penetration probe rotatably supported on the main body, a penetration device connected to the penetration probe, and a measuring device connected to the main body; The penetration probe includes a rod and a penetration member having a tapered tip provided at the lower end of the rod, and the penetration device is connected to the upper end of the rod; a sensor unit having two or more ring-shaped electrodes sandwiched between insulators, and wiring connected to the ring-shaped electrodes and disposed inside the rod, at an intermediate portion of the rod; the wiring is electrically connected to the electrical signal input / output unit of the main body via a slip ring provided on a pivotal support of the main body; The measuring device is connected to the electrical signal input / output unit. Secondly, in the ground electrical characteristic measuring device of the first invention, it is preferable that each of the two or more ring-shaped electrodes and the insulator of the sensor unit is provided detachably. Thirdly, in the ground electrical characteristic measuring device according to the first or second invention, it is preferable that the penetrating member is provided detachably. Fourth, in the ground electrical characteristic measuring device of the first to third inventions, it is preferable that the penetration device is an electric or manual rotating device and is detachably attached to the upper end of the penetration probe. Fifth, in the ground electrical characteristic measuring device according to the first to fourth aspects of the present invention, it is preferable that a bearing is provided on a shaft support portion of the main body for the penetration probe. Sixth, in the ground electrical characteristic measuring device of the first to fifth inventions above, it is preferable that the main body is provided with a support member for preventing the main body from rotating in conjunction with the rotation of the penetration probe and for pressing the penetration probe vertically against the ground. Seventh, in the ground electrical characteristic measuring device according to the first to sixth inventions, it is preferable that the measuring device is capable of measuring any one of the electrical resistance, dielectric constant, and resistivity of the ground. Eighth, in the ground electrical characteristic measuring device of the first to seventh inventions above, it is preferable that the measuring equipment connected to the electrical signal input / output unit of the main body has a function of transmitting and receiving acquired data and is connected to other equipment via wire or wirelessly so that data can be stored. Ninth, in the ground electrical characteristic measuring device according to any one of the first to eighth aspects of the present invention, it is preferable that the measuring device is capable of acquiring position information of the penetration probe. [Effects of the Invention]

[0010] The ground electrical characteristics measuring device of the present invention can easily grasp the compaction status of an embankment by measuring the electrical characteristics of each soil type at any location on the embankment. Furthermore, the measurement work is not time-consuming, and there is no need for complicated work or human error. Furthermore, since the complicated work of penetrating electrodes into the ground can be reduced, there is less chance of human error in the measurement, and measurements can be performed efficiently and accurately. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram of an embodiment of a ground electrical characteristic measuring device according to the present invention. [Figure 2] 1A to 1D are schematic diagrams showing variations of the penetration member, in which (A) to (D) are front views and (A') to (D') are top views. [Figure 3] 1 is a schematic cross-sectional view of an embodiment of a sensor portion. [Figure 4] 10 is a schematic cross-sectional view showing a shaft support portion of the penetration probe in the main body. FIG. [Figure 5] 1A and 1B are schematic diagrams showing variations of the support member, in which (A) and (B) are front views, and (A') and (B') are top views. [Figure 6] 1 is a schematic diagram showing a hammer penetration device. FIG. [Figure 7] FIG. 2 is a schematic diagram showing a connection configuration of a measuring device. [Figure 8] FIG. 2 is a schematic diagram showing a state in which the ground electrical characteristic measuring device is fixed to a stand. DETAILED DESCRIPTION OF THE INVENTION

[0012] The ground electrical characteristic measuring device of the present invention will be described in detail below with reference to the drawings, showing an embodiment of the invention. Figure 1 is a schematic diagram of one embodiment of the ground electrical characteristic measuring device of the present invention.

[0013] The ground electrical characteristic measuring device 1 (hereinafter also referred to as the measuring device) of this embodiment is a measuring device that measures the electrical characteristics of the ground, and is equipped with a main body 2, a penetrating probe 3 that penetrates the main body 2 and is rotatably supported, and a measuring instrument 5 connected to the main body 2.

[0014] <Penetration Probe> The penetration probe 3 includes a rod 31, a penetration member 32 provided at the lower end of the rod 31, and a sensor unit 33 provided at the middle part of the rod 31. In addition, a penetration device 4 is provided at the upper end of the rod 31.

[0015] The rod 31 in the penetration probe 3 of this embodiment is a long tubular member, and the material is not limited as long as it is not easily deformed or broken by the rotation of the penetration probe 3, and examples that can be used include stainless steel pipes, aluminum pipes, and polyvinyl chloride pipes. The length of the rod 31 is preferably about 20 to 100 cm, and the outer diameter is preferably about 5 to 30 mm.

[0016] The penetration member 32 attached to the lower end of the rod 31 is a member for easily penetrating the penetration probe 3 into the ground, and has a tapered (conical) tip, and can be of a shape suitable for the properties of the ground. Specific examples include a linear tapered reamer shape as shown in Figure 2(A) and a drill shape as shown in Figures 2(B) to 2(D).

[0017] The angle of the tip of the penetration member 32 is preferably 10 to 90 degrees from the viewpoint of ease of penetration into the ground. In addition, the inclination of the spiral ridges, depressions, and blades of the drill shown in Figures 2(B) to 2(D) is preferably 0 to 90 degrees, and the angle between the extension direction of the blades and the penetration direction of the penetration probe 3 is preferably 90 degrees or more.

[0018] Furthermore, it is preferable that the penetrating member 32 is connected in a detachable manner. As a connection method, for example, a male or female screw may be formed at the rear end of the penetrating member 32, and a female or male screw may be formed at the tip end of the rod 31, and these may be screwed together to easily connect them in a detachable manner. By connecting the penetrating member 32 in a detachable manner, it is possible to easily change the shape of the penetrating member 32 to one that is appropriate for the characteristics of the ground, and it is also easy to replace the penetrating member 32 if it is damaged due to wear during penetration, etc.

[0019] 1 and 3, the sensor unit 33 provided in the middle of the rod 31 has a configuration in which a ring-shaped electrode 331 is sandwiched between insulators 332 in the longitudinal direction. A wiring 333 is connected to the ring-shaped electrode 331, and the wiring 333 is disposed inside the rod 31 facing upward as shown in Fig. 3. The position of the sensor unit 33 can be determined appropriately taking into account the depth of penetration into the ground, but it is usually preferable to provide it as close to the tip of the rod 31 as possible.

[0020] The ring-shaped electrode 331 and the insulator 332 are each independently detachable. Two or more ring-shaped electrodes 331 are provided, and preferably four or more considering the type of data to be measured. The detachable ring-shaped electrode 331 and the insulator 332 can be fixed, for example, by providing a step at the lower end of the rod 31 to fit the ring-shaped electrode 331 and the insulator 332, as shown in FIG. 3 . Alternatively, by providing a hollow structure extending longitudinally from the lower end of the rod 31, the wiring 333 connected to the ring-shaped electrode 331 can be disposed within the rod 31. In this case, the contact surface between the surface of the rod 31 and the ring-shaped electrode 331 must be insulated. By making the ring-shaped electrode 331 and the insulator 332 detachable, they can be easily replaced even if they wear or are damaged due to penetration into the ground.

[0021] The material used for the ring-shaped electrode 331 is not particularly limited as long as it is conductive and does not easily wear or break. For example, metals such as aluminum, iron, copper, gold, silver, etc., alloys such as stainless steel, or other conductive substances can be used.

[0022] The material used for the insulator 332 may be, for example, vinyl chloride, phenolic resin, glass, rubber, plastic, or other non-conductive material.

[0023] The width of the insulator 332 (the width between the electrodes) and the electrode width can be determined appropriately depending on the ground to be measured, etc., and are not particularly limited, but from the viewpoint of reliability of the measurement data, the width of the insulator 332 is preferably 1 to 60 mm, more preferably 20 mm. The electrode width is preferably 1 to 10 mm, more preferably 5 mm. The outer diameter of the sensor part 33 is preferably 5 to 30 mm, which is approximately the same as the outer diameter of the rod 31.

[0024] A penetration device 4 is provided at the upper end of the rod 31. The penetration device 4 is a device for penetrating the ground while rotating the penetration probe 3, and can be an electric penetration device 41 as shown in Figure 1 or a rotation device for a manual penetration device. Penetration by hitting with a hammer 42 or the like as shown in Figure 6 is also possible.

[0025] Examples of the electric penetration device 41 include an electric drill and a hammer drill. In addition to being rechargeable, these can be connected to a portable generator, earthwork construction machinery, self-propelled sampler, etc. to supply power and operate. Examples of the manual penetration device include a manual hand drill. These manual penetration devices can be rotated by human power.

[0026] The rotation speed and rotation torque of the penetration device 4 are set to a low speed that does not cause excessive damage due to friction to the sensor unit 33, etc. The rotation speed is preferably 1 to 1000 rpm, more preferably 1 to 100 rpm, and even more preferably 1 to 50 rpm. The rotation torque is preferably 10 N m or more, more preferably 100 N m or more, and even more preferably 200 N m or more.

[0027] In addition, it is preferable that the penetration device 4 be configured to be detachably attached to the upper end of the rod 31. By making the penetration device 4 detachable, portability can be improved, and by removing the penetration device 4 after the penetration probe 3 has penetrated, safety during work can be ensured, the load on the penetration probe 3 due to the weight of the penetration means can be reduced, and the penetration probe 3 itself can be made to stand on its own. In addition, the penetration device 4 can be easily attached and detached using a drill chuck or the like.

[0028] The penetration probe 3 can be easily penetrated into the ground by the operation of the penetration device 4. After measurement, the penetration probe 3 can be easily withdrawn by applying a torque in the opposite direction to that applied when penetrating.

[0029] <Main body> The main body 2 of the measuring device 1 of this embodiment has the penetration probe 3 configured as described above rotatably supported while passing through the main body 2. The support portion is preferably located near the upper end of the penetration probe 3, and as shown in Figure 4, a bearing 23 is provided to ensure smooth axial rotation of the penetration probe 3.

[0030] The penetration probe 3 is supported on the main body 2 via bearings 23, which allows it to rotate smoothly in the direction of the rotation axis, but it does not move in the axial direction (up and down).Therefore, when the main body 2 is pressed vertically toward the ground, the force can be transmitted directly in the axial direction of the penetration probe 3, making it easy to penetrate the penetration probe 3 into the ground.

[0031] In addition, the main body 2 is provided with an electrical signal input / output unit 21 and a slip ring 22, and the wiring 333 of the penetration probe 3 is electrically connected to the electrical signal input / output unit 21 via the slip ring 22. With the above configuration, even when a rotational force is applied to the penetration probe 3 by the penetration device 4, the cable extended from the sensor unit 33 is not affected by the rotation due to the slip ring 22 provided on the main body 2. In other words, with the sensor unit 33 of the penetration probe 3 penetrated into the ground, information acquired by the sensor unit 33 can be output from the output terminal based on a predetermined electrical signal input from the input terminal of the electrical signal input / output unit 21.

[0032] Furthermore, the main body 2 can be provided with a cylindrical support member 24 that protrudes horizontally from the side of the main body 2. The support member 24 is a member that can be held by hand to support the measuring device 1, and it prevents the main body 2 from rotating in conjunction with the rotation of the penetration probe 3, and also makes it easier to press the penetration probe 3 vertically against the ground.

[0033] The shape of the support part is not particularly limited as long as it is easy for a person to grip and to apply pressure from above. For example, it may have a grip to prevent slipping at the gripping point as shown in Figures 5(A) and (A'), or it may have a curved auxiliary part formed at the end as shown in Figures 5(B) and (B').

[0034] <Measuring equipment> A measuring device 5 is connected to the electrical signal input / output unit 21 of the main body 2. The measuring device 5 is a device that inputs a predetermined electrical signal from the input terminal of the electrical signal input / output unit 21, and obtains and analyzes electrical information acquired by the sensor unit 33 from the output terminal. Examples of electrical information that can be measured by the measuring device 5 include electrical resistance, conductivity, and specific resistance. A specific example of the measuring device 5 that can be used is the GeoVES-1 earth resistivity meter / ground resistance meter (manufactured by Geofive Co., Ltd.), which can accurately measure the electrical properties of the ground.

[0035] The measuring device 5 is usually connected to the electrical signal input / output unit 21 of the main body 2 via a cable as shown in FIG. 7(A) and is installed separately for use. By making it detachable from the main body 2 in this way, the measuring device 5 can be removed when penetrating the penetration probe 3 to perform the penetration work, and the measuring device 5 can be attached after the penetration probe 3 has penetrated, making it easier to handle the device during work and improving workability and safety. In addition, the measuring device 5 can also be configured as an integrated unit of the main body 2 and the measuring device 5 as shown in FIG. 7(B).

[0036] 7(C), a configuration can also be adopted in which a transmitter / receiver 51 is connected to the electrical signal input / output unit 21 and the acquired data is transmitted to the measuring device 5. This makes it possible to transmit and receive data within the range of radio waves between the main body 2 and the measuring device 5. In this configuration, it is necessary to separately consider the supply of electricity to the penetration probe 3.

[0037] Furthermore, the main body 2 can be provided with a position measurement means. For example, a GPS can be used as the position measurement means. By providing the position measurement means, it becomes possible to record the exact position of the penetration probe 3, grasp the electrical properties of the ground on a planar basis, and thereby predict the distribution of soil quality.

[0038] The measuring device 5 can also be provided with a function for transmitting and receiving acquired data, allowing it to be connected to other devices via wired or wireless connections. Specifically, the data acquired by the measuring device 5 can be sent to a computer using the transmitting and receiving function, where it can be stored and analyzed. Furthermore, the measuring device 5 can be connected to the Internet using the transmitting and receiving function, allowing data to be stored on a specific server or cloud environment on the Internet.

[0039] In addition, in the present invention, the electrical characteristic measuring apparatus 1 can also be used by fixing it to a stand 6 that can be raised and lowered, as shown in Figure 8. In this usage mode, the main body 2 of the measuring apparatus 1 is fixed to the arm portion 61 of the stand 6, so that the support member 24 that is used to hold the measuring apparatus 1 by hand can be omitted. Using the stand 6 makes it easy to position and support the measuring apparatus 1, thereby improving workability and measurement accuracy. Furthermore, providing wheels or crawlers at the bottom of the stand 6 improves portability and makes it easier to measure over a large area.

[0040] The ground electrical characteristics measuring device of the present invention having the above-mentioned configuration allows the penetration probe to be easily pressed perpendicularly against the ground and penetrated. After penetration, the electrical characteristics of the ground obtained by the sensor unit can be measured and analyzed in that state. [Explanation of symbols]

[0041] 1. Electrical property measuring equipment 2 Main unit 21 Electrical signal input / output section 22 slip ring 23 Bearings 24 Support member 3 Penetration Probe 31 Rod 32 Penetrating member 33 Sensor section 331 Ring Electrode 332 Insulator 333 Wiring 4 Penetration device 41 Electric penetration device 42 Hammer 5 Measuring equipment 51 Transmitting and receiving equipment 6 Stand 61 Arm section

Claims

1. A measuring device for measuring electrical characteristics of the ground, The apparatus includes a main body, a penetration probe rotatably supported on the main body, a penetration device connected to the penetration probe, and a measuring device connected to the main body; The penetration probe includes a rod and a penetration member having a tapered tip provided at the lower end of the rod, and the penetration device is connected to the upper end of the rod; a sensor unit having two or more ring-shaped electrodes sandwiched between insulators, and wiring connected to the ring-shaped electrodes and disposed inside the rod, at an intermediate portion of the rod; the wiring is electrically connected to the electrical signal input / output unit of the main body via a slip ring provided on a pivotal support of the main body; the measuring device is connected to the electrical signal input / output unit, 1. A ground electrical characteristic measuring device, comprising: two or more ring-shaped electrodes and an insulator of the sensor unit, each of which is detachably provided.

2. A ground electrical characteristic measuring device as described in Claim 1, characterized in that the penetrating member is detachably provided.

3. The ground electrical characteristic measuring device according to claim 1 or 2, characterized in that the penetration device is an electric or manual rotating device and is detachably attached to the upper end of the penetration probe.

4. A ground electrical characteristic measuring device as described in any one of claims 1 to 3, characterized in that a bearing is provided in the axial support portion of the penetration probe of the main body.

5. An electrical characteristic measuring device for ground described in any one of claims 1 to 4, characterized in that the main body is provided with a support member that prevents the main body from rotating due to the rotation of the penetration probe and that presses the penetration probe vertically against the ground.

6. An electrical property measuring device for ground described in any one of claims 1 to 5, characterized in that the measuring instrument is capable of measuring any of the electrical resistance, dielectric constant, or resistivity of the ground.

7. A ground electrical characteristic measuring device described in any one of claims 1 to 6, characterized in that the measuring equipment connected to the electrical signal input / output unit of the main body has the function of transmitting and receiving acquired data and is connected to other equipment via wired or wireless connection so that data can be accumulated.

8. An electrical property measuring device for ground described in any one of claims 1 to 7, characterized in that the measuring equipment is capable of acquiring position information of the penetration probe.

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