Specific Resistance Measuring Apparatus and Specific Resistance Measuring Method

Abstract

To provide a specific resistance measuring device and a specific resistance measuring method with which it is possible to measure the specific resistance of earth on ground surface, while moving from one location to another, mitigating the influence of unevenness of ground surface.SOLUTION: Provided is a specific resistance measuring device 1A comprising a body unit 10A that moves on ground surface S and an electrode unit 20A that approaches the ground surface S from the body unit 10A and measures the specific resistance of earth E on the ground surface S, wherein the electrode unit 20A repeats approaching the ground surface S and separating from the ground surface S and measures the specific resistance of the earth E on ground surface S when having approached the ground surface S, so that variation in the measured values of the specific resistance of the earth E on the ground surface S due to the unevenness of the ground surface S hardly occurs, as compared with the case where the electrode is always in contact with the ground surface during the travel of a vehicle. Therefore, it is possible to measure the specific resistance of the earth E on the ground surface S while moving from one location to another mitigating the influence of the unevenness of the ground surface S.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a specific resistance measuring device and a specific resistance measuring method.

Background Art

[0002] Techniques for measuring the specific resistance of soil on the ground using electrodes in contact with the ground have been proposed. For example, Patent Document 1 discloses a vehicle equipped with electrodes for measuring the specific resistance of soil on the ground. The vehicle travels while the electrodes are held in contact with the ground at a constant pressure by a hydraulic jack. During the travel of the vehicle, the specific resistance of the soil on the ground is measured by a plurality of electrodes in contact with the ground at a constant pressure. Thereby, it is possible to measure the specific resistance of the soil on the ground at many measurement locations while moving the vehicle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the above-described technique, due to unevenness of the ground, the contact area between the electrode and the ground may vary during the travel of the vehicle. When the contact area between the electrode and the ground varies, there is a problem that variations also occur in the measured value of the specific resistance of the soil on the ground measured by the electrode.

[0005] Therefore, an object of the present invention is to provide a specific resistance measuring device and a specific resistance measuring method capable of measuring the specific resistance of soil on the ground while moving while reducing the influence of unevenness of the ground.

Means for Solving the Problems

[0006] The present invention includes a main body that moves on the ground and an electrode unit that is close to the ground from the main body and measures the specific resistance of the soil on the ground. The electrode unit repeatedly approaches and separates from the ground and measures the specific resistance of the soil on the ground when it is close to the ground, and is a specific resistance measuring device.

[0007] According to this configuration, in a specific resistance measuring device including a main body that moves on the ground and an electrode unit that is close to the ground from the main body and measures the specific resistance of the soil on the ground, the electrode unit repeatedly approaches and separates from the ground and measures the specific resistance of the soil on the ground when it is close to the ground. Therefore, compared with the case where the electrode and the ground are always in contact during the running of the vehicle, the measured value of the specific resistance of the soil on the ground is less likely to vary due to unevenness of the ground. Therefore, it is possible to measure the specific resistance of the soil on the ground while moving while reducing the influence of the unevenness of the ground.

[0008] In this case, it is preferable that the electrode unit has a plurality of legs that move the main body on the ground by repeatedly contacting and separating from the ground and walking, and measures the specific resistance of the soil on the ground when the legs contact the ground.

[0009] According to this configuration, the electrode unit has a plurality of legs that move the main body on the ground by repeatedly contacting and separating from the ground and walking, and measures the specific resistance of the soil on the ground when the legs contact the ground. Therefore, it is possible to move on the ground without always contacting the electrode unit and the ground.

[0010] In this case, the main body has a first separated part and a second separated part separated from the first separated part. The electrode part has four pairs of legs. One of the two pairs of legs among the four pairs of legs is arranged on the first separated part, and the first separated part is moved on the ground by repeatedly walking with contact with the ground and separation from the ground. The other two pairs of legs among the four pairs of legs are arranged on the second separated part, and the second separated part is moved on the ground by repeatedly walking with contact with the ground and separation from the ground. One of the two pairs of legs arranged on the first separated part and the other two pairs of legs arranged on the second separated part repeatedly walk in synchronization with each other with contact with the ground and separation from the ground. When two legs among the two pairs of legs arranged on the first separated part and two legs among the two pairs of legs arranged on the second separated part come into contact with the ground, it is preferable that the electrode part measures the specific resistance of the soil on the ground.

[0011] According to this configuration, the main body has a first separated part and a second separated part separated from the first separated part. The electrode part has four pairs of legs. One of the two pairs of legs among the four pairs of legs is arranged on the first separated part, and the first separated part is moved on the ground by repeatedly walking with contact with the ground and separation from the ground. The other two pairs of legs among the four pairs of legs are arranged on the second separated part, and the second separated part is moved on the ground by repeatedly walking with contact with the ground and separation from the ground. Since the first separated part and the second separated part can each move on the ground by four-legged walking, the structure of each of the first separated part and the second separated part can be simplified, and each of the first separated part and the second separated part can be made small.

[0012] Also, one of the two pairs of legs arranged on the first separated part and the other two pairs of legs arranged on the second separated part repeatedly walk in synchronization with each other with contact with the ground and separation from the ground. When two legs among the two pairs of legs arranged on the first separated part and two legs among the two pairs of legs arranged on the second separated part come into contact with the ground, the electrode part measures the specific resistance of the soil on the ground. Therefore, for example, by changing the distance between the first separated part and the second separated part, the depth from the ground of the soil for measuring the specific resistance can be changed.

[0013] Further, when the electrode unit has a plurality of leg portions, it further includes a measurement management unit that manages the value of the specific resistance of the soil on the ground measured by the electrode unit. When the difference in the contact time of each of the plurality of leg portions with the ground is greater than a threshold value, it is preferable that the measurement management unit deletes the value of the specific resistance of the soil on the ground measured by the electrode unit.

[0014] According to this configuration, when the difference in the contact time of each of the plurality of leg portions with the ground is greater than the threshold value and it is expected that the accuracy of the specific resistance value measured by the electrode unit is low, the measurement management unit that manages the value of the specific resistance of the soil on the ground measured by the electrode unit deletes the value of the specific resistance of the soil on the ground measured by the electrode unit, so that only the specific resistance values with high measurement accuracy can be left.

[0015] Further, the main body unit has a moving unit that moves the main body unit on the ground. When the main body unit is being moved on the ground by the moving unit, the electrode unit may repeatedly approach and separate from the ground, and measure the specific resistance of the soil on the ground when approaching the ground.

[0016] According to this configuration, the main body unit has a moving unit that moves the main body unit on the ground. When the main body unit is being moved on the ground by the moving unit, the electrode unit repeatedly approaches and separates from the ground, and measures the specific resistance of the soil on the ground when approaching the ground. Therefore, the electrode unit can move on the ground without always contacting the ground.

[0017] Further, the electrode unit has a capacitor electrode composed of a dielectric facing the ground and a conductor connected to the dielectric. The dielectric repeatedly approaches and separates from the ground, and it is preferable that the electrode unit measures the specific resistance of the soil on the ground when the dielectric approaches the ground.

[0018] According to this configuration, the electrode unit has a capacitor electrode composed of a dielectric facing the ground and a conductor connected to the dielectric. The dielectric repeats approaching and separating from the ground, and when the dielectric approaches the ground, the electrode unit measures the specific resistance of the soil on the ground. Since the capacitor electrode can measure the specific resistance of the soil on the ground only by bringing the dielectric close to the ground, the influence of unevenness on the ground can be further reduced.

[0019] Further, the electrode unit has a facing surface facing the ground, and the facing surface includes a contact surface that contacts the ground and a non-contact surface that does not contact the ground. The contact surface is constituted by either a plane parallel to the ground or a curved surface protruding with respect to the ground. The contact surface and the non-contact surface are connected by a curved surface. The contact surface repeats contacting and separating from the ground, and when the contact surface contacts the ground, it is preferable that the electrode unit measures the specific resistance of the soil on the ground.

[0020] According to this configuration, the electrode unit has a facing surface facing the ground, and the facing surface includes a contact surface that contacts the ground and a non-contact surface that does not contact the ground. The contact surface is constituted by either a plane parallel to the ground or a curved surface protruding with respect to the ground. The contact surface and the non-contact surface are connected by a curved surface. The contact surface repeats contacting and separating from the ground, and when the contact surface contacts the ground, the electrode unit measures the specific resistance of the soil on the ground. Therefore, for example, while reducing the disturbance of the ground after the embankment is compacted by a roller, the specific resistance of the soil on the ground can be measured while moving.

[0021] Moreover, it is preferable to further include a positioning unit that positions the position of the main body unit, and a storage unit that stores in association the value of the specific resistance of the soil on the ground measured by the electrode unit and the position of the main body unit measured by the positioning unit.

[0022] According to this configuration, since the storage unit stores in association the value of the specific resistance of the soil on the ground measured by the electrode unit and the position of the main body unit measured by the positioning unit, it is easy to grasp the relationship between the position and the specific resistance of the soil on the ground at that position.

[0023] On the one hand, the present invention includes a moving step in which the main body moves above the ground, and a specific resistance measuring step in which an electrode part close to the ground from the main body measures the specific resistance of the soil on the ground. In the specific resistance measuring step, the electrode part repeatedly approaches and separates from the ground, and measures the specific resistance of the soil on the ground when approaching the ground. This is a specific resistance measuring method.

[0024] In this case, the electrode part has a plurality of legs that move the main body above the ground by repeatedly contacting and separating from the ground and walking. In the specific resistance measuring step, it is preferable that the electrode part measures the specific resistance of the soil on the ground when the leg contacts the ground.

Advantages of the Invention

[0025] According to the specific resistance measuring device and method of the present invention, it is possible to measure the specific resistance of the soil on the ground while moving while reducing the influence of unevenness of the ground.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0027] Hereinafter, embodiments of a specific resistance measuring apparatus and a specific resistance measuring method according to the present invention will be described in detail with reference to the drawings. The specific resistance measuring apparatus and the specific resistance measuring method according to the first embodiment of the present invention measure, while moving, the specific resistance of the soil on the ground after being compacted by a compaction machine such as a road roller during the construction process of geotechnical work, and evaluate the quality of the soil on the ground by deriving the dry density or wet density of the soil that is correlated with the specific resistance, and are for confirming the compaction effect by the compaction machine.

[0028] As shown in FIGS. 1(A), 1(B), and 2, the specific resistance measuring apparatus 1A of the present embodiment includes a main body portion 10A and an electrode portion 20A. The main body portion 10A moves on the ground S. The electrode portion 20A approaches the ground S from the main body portion 10A and measures the specific resistance of the soil E on the ground S. In the specific resistance measuring apparatus 1A of the present embodiment, the electrode portion 20A does not always contact the ground S, but repeatedly approaches and separates from the ground S, and measures the specific resistance of the soil E on the ground S when approaching the ground S. That is, the specific resistance measuring apparatus 1A of the present embodiment measures the specific resistance of the soil E on the ground S discretely.

[0029] The electrode portion 20A has a plurality of legs 21, 22, 23, 24, 25, 26, 27, 28 that repeatedly contact and separate from the ground S to move the main body portion 10A on the ground S by walking. The electrode portion 20A measures the specific resistance of the soil E on the ground S when the legs 21, 22, 23, 24, 25, 26, 27, 28 contact the ground S. That is, in the present embodiment, the legs 21, 22, 23, 24, 25, 26, 27, 28 function as electrodes for measuring the specific resistance of the soil E on the ground S.

[0030] More specifically, the main body portion 10A has a first split portion 11 and a second split portion 12 separated from the first split portion 11. The first split portion 11 and the second split portion 12 have the same configuration as each other. The specific resistance measuring apparatus 1A of the present embodiment measures the specific resistance of the soil E on the ground S with the first split portion 11 and the second split portion 12 as a set. The electrode portion 20A has a total of four pairs of legs 21, 22, 23, 24, 25, 26, 27, 28.

[0031] One of the two pairs of legs among the four pairs of legs 21, 22, 23, 24, 25, 26, 27, 28, namely legs 21, 22, 23, 24, is arranged on the first split part 11, and the first split part 11 is moved on the ground S by repeatedly walking while contacting and separating from the ground S. The other two pairs of legs among the four pairs of legs 21, 22, 23, 24, 25, 26, 27, 28, namely legs 25, 26, 27, 28, are arranged on the second split part 12, and the second split part 12 is moved on the ground S by repeatedly walking while contacting and separating from the ground S. That is, the first split part 11 and the second split part 12 are configured as a robot capable of moving on the ground S by quadruped walking through autonomous control or remote operation.

[0032] One of the two pairs of legs 21, 22, 23, 24 arranged on the first split part 11 and the other two pairs of legs 25, 26, 27, 28 arranged on the second split part 12 repeatedly walk while contacting and separating from the ground S in synchronization with each other. When either one of the two legs 21, 24 and the legs 22, 23 among the two pairs of legs 21, 22, 23, 24 arranged on the first split part 11 and either one of the two legs 25, 28 and the legs 26, 27 among the other two pairs of legs 25, 26, 27, 28 arranged on the second split part 12 contact the ground S, the electrode part 20A measures the specific resistance of the soil E of the ground S.

[0033] A robot moving on the ground S by quadruped walking such as the first split part 11 and the second split part 12 changes the footfall according to the speed range, for example, to normal walk (walk), fast walk (trot), and canter. In the medium speed range suitable for measuring the soil E of the ground S, the first split part 11 moves by trot walking in which the leg 21 which is the front left diagonal leg and the leg 24 which is the rear right diagonal leg in plan view contact synchronously, and the leg 22 which is the front right diagonal leg and the leg 23 which is the rear left diagonal leg in plan view contact synchronously. Similarly, in the medium speed range, the second split part 12 moves by trot walking in which the leg 25 which is the front left diagonal leg and the leg 28 which is the rear right diagonal leg in plan view contact synchronously, and the leg 26 which is the front right diagonal leg and the leg 27 which is the rear left diagonal leg in plan view contact synchronously.

[0034] When walking at a fast pace, in a plan view, the diagonal legs 21, 24, etc. contact the ground S at a substantially constant distance. That is, the distance between the two electrodes in contact with the ground S of the legs 21, 24, etc. in each of the first divided body part 11 and the second divided body part 12 is always maintained constant. Also, by maintaining the distance between the first divided body part 11 and the second divided body part 12 constant, and having the legs 21, 24, etc. of the first divided body part 11 and the legs 25, 28, etc. of the second divided body part 12 repeatedly contact and separate from the ground S in synchronization with each other to walk, the distance between the four electrodes in contact with the ground S of either the legs 21, 24, 25, 28 or the legs 22, 23, 26, 27 in the first divided body part 11 and the second divided body part 12 is always maintained constant.

[0035] This constitutes an electrode arrangement called the dipole-dipole method (quadrupole method) in the electrical exploration shown in FIG. 2. Four of the legs 21, 22, 23, 24, 25, 26, 27, 28 of the electrode part 20A that contact the ground S, i.e., the legs 21, 24, 25, 28 or the legs 22, 23, 26, 27, serve as electrodes to measure the specific resistance of the soil E. Also, the measurement depth of the specific resistance is determined by the arrangement of the legs 21, etc. that are electrodes. When the distance between the inner two electrodes of the four electrodes, i.e., the legs 24, 25 or the legs 23, 26, is set as na, and the distance between the other two adjacent electrodes, i.e., the legs 21, 24, etc., is set as a, the measurement depth becomes a(n + 1) / 2.

[0036] As shown in FIGS. 3(A) and 3(B), the electrode portion 20A has a capacitor electrode 30A composed of a dielectric 31 facing the ground S and a conductor 32 connected to the dielectric 31. The dielectric 31 repeatedly approaches and separates from the ground S, and when the dielectric 31 approaches the ground S, the electrode portion 20A measures the specific resistance of the soil E of the ground S. The dielectric 31 is made of a general synthetic resin. Since the dielectric 31 directly contacts the ground S, it is preferably a material that can withstand the situation. The dielectric 31 is preferably made of, for example, high-density polyethylene, rigid polyurethane, and ABS (Acrylonitrile-butadiene styrene) resin. The conductor 32 is made of a conductive metal.

[0037] The capacitor electrode 30A such as the leg portion 21 of the electrode portion 20A has a facing surface 40A facing the ground S. In the examples of FIGS. 3(A) and 3(B), the facing surface 40A is a spherical surface. The facing surface 40A includes a contact surface 41A that contacts the ground S and a non-contact surface 42A that does not contact the ground S around the contact surface 41A. The contact surface 41A is constituted by either a plane parallel to the ground S or a curved surface protruding with respect to the ground S.

[0038] In the examples of FIGS. 3(A) and 3(B), the contact surface 41A is constituted by a spherical surface protruding with respect to the ground S. The non-contact surface 42A is constituted by a spherical surface continuous with the contact surface 41A. Therefore, the contact surface 41A and the non-contact surface 42A are connected by a curved surface that is a spherical surface. The contact surface 41A repeatedly contacts and separates from the ground S, and when the contact surface 41A contacts the ground S, the capacitor electrode 30A such as the leg portion 21 of the electrode portion 20A measures the specific resistance of the soil E of the ground S. In order to reduce the influence of unevenness of the ground S, the area of the contact surface 41A is preferably as small as possible. For example, the area of the contact surface 41A is 0.10 m 2 or less, and more preferably 0.05 m 2 or less.

[0039] In addition, in this embodiment, the specific resistance measuring device 1A may include an electrode portion 20B as shown in FIGS. 3(C) and 3(D). In the examples of FIGS. 3(C) and 3(D), the capacitor electrode 30B such as the leg portion 21 of the electrode portion 20B has a facing surface 40B which is the side surface of a cylinder. The facing surface 40B includes a contact surface 41B that contacts the ground S and non-contact surfaces 42B that do not contact the ground S before and after the contact surface 41B. The contact surface 41B is constituted by the side surface of a cylinder protruding with respect to the ground S. The non-contact surfaces 42B are constituted by the side surfaces of the cylinder continuous with the contact surface 41B. Therefore, the contact surface 41B and the non-contact surfaces 42B are connected by a curved surface which is the side surface of the cylinder. The contact surface 41B repeats contact with and separation from the ground S, and when the contact surface 41B contacts the ground S, the capacitor electrode 30B such as the leg portion 21 of the electrode portion 20B measures the specific resistance of the soil E of the ground S.

[0040] Also, in this embodiment, the specific resistance measuring device 1A may include an electrode portion 20C as shown in FIGS. 3(E) and 3(F). In the examples of FIGS. 3(E) and 3(F), the capacitor electrode 30C such as the leg portion 21 of the electrode portion 20C has a facing surface 40C which is the bottom surface of a sled. The facing surface 40C includes a contact surface 41C that contacts the ground S and non-contact surfaces 42C that do not contact the ground S before and after the contact surface 41C. In the examples of FIGS. 3(E) and 3(F), the contact surface 41C is a plane parallel to the ground S. The non-contact surfaces 42C are curved surfaces that protrude with respect to the ground S and are spaced upward from the ground S so as to be separated in the front-rear direction from the contact surface 41C. The contact surface 41C and the non-contact surfaces 42C are connected by a curved surface protruding with respect to the ground S. The contact surface 41C repeats contact with and separation from the ground S, and when the contact surface 41C contacts the ground S, the capacitor electrode 30C such as the leg portion 21 of the electrode portion 20C measures the specific resistance of the soil E of the ground S.

[0041] As shown in FIGS. 1(A), 1(B) and 2, the specific resistance measuring device 1A further includes a measurement management unit 50 that manages the value of the specific resistance of the soil E on the ground S measured by the electrode unit 20A. When the difference in the contact time of each of either one of the plurality of legs 21, 24, 25, 28 and the legs 22, 23, 26, 27 with the ground S is greater than a threshold value, the measurement management unit 50 deletes the value of the specific resistance of the soil E on the ground S measured by the electrode unit 20A. The threshold value can be set to a smaller value as the required accuracy of the specific resistance measurement is higher, for example.

[0042] Note that the measurement management unit 50 may be located outside the first split unit 11 and the second split unit 12 of the main body unit 10A, receive the specific resistance of the soil E on the ground S measured from the first split unit 11 and the second split unit 12 and the contact time of the plurality of legs 21, etc. with the ground by wireless communication, and process the value of the specific resistance.

[0043] The specific resistance measuring device 1A includes a positioning unit 61 that positions the positions of the first split unit 11 and the second split unit 12 of the main body unit 10A. The positioning unit 61 positions the positions of the first split unit 11 and the second split unit 12 of the main body unit 10A by, for example, GNSS (Global Navigation Satellite System) surveying, automatic tracking TS (Total Station) by an optical surveying function, etc. The specific resistance measuring device 1A includes a storage unit 62 that associates and stores the value of the specific resistance of the soil E on the ground S measured by the electrode unit 20A and the positions of the first split unit 11 and the second split unit 12 of the main body unit 10A positioned by the positioning unit 61. The storage unit 62 is a recording medium such as a hard disk, for example.

[0044] Note that the storage unit 62 may be located outside the first split unit 11 and the second split unit 12 of the main body unit 10A, receive the value of the specific resistance of the soil E on the ground S measured by the electrode unit 20A and the positions of the first split unit 11 and the second split unit 12 of the main body unit 10A positioned by the positioning unit 61 by wireless communication, and associate and store the value of the specific resistance and the position of the main body unit 10A.

[0045] When the resistivity measuring device 1A of the present embodiment measures the resistivity of the soil E on the ground S, for example, after the soil E on the ground S is compacted by a compaction machine such as a road roller during the construction process of geotechnical work, a moving step in which the main body 10A moves on the ground S and a resistivity measuring step in which the electrode unit 20A approaching the ground S from the main body 10A measures the resistivity of the soil E on the ground S are performed. In the moving step and the resistivity measuring step, for example, the resistivity measuring device 1A performs wireless communication with a compaction machine that compacts the soil E on the ground S by autonomous control, and the main body 10A moves by autonomous control with respect to the position where the soil E on the ground S is compacted by the compaction machine, and the electrode unit 20A may measure the resistivity of the soil E on the ground S at that position.

[0046] In the resistivity measuring step, the electrode unit 20A repeatedly approaches and separates from the ground S, and measures the resistivity of the soil E on the ground S when approaching the ground S. As described above, the electrode unit 20A has a plurality of legs 21 and the like that move the main body 10A on the ground S by repeatedly walking in contact with and separating from the ground S, and in the resistivity measuring step, the electrode unit 20A measures the resistivity of the soil E on the ground S when the leg 21 contacts the ground S.

[0047] In the moving step, for example, as shown in FIG. 2, the first split part 11 of the main body 10A moves, and the second split part 12 of the main body 10A moves so as to chase at a certain distance from the first split part 11. The legs 21 and the like of the first split part 11 and the legs 25 and the like of the second split part 12 repeatedly walk in contact with and separating from the ground S in synchronization with each other.

[0048] For example, when the legs 21, 24 of the first split part 11 and the legs 25, 28 of the second split part 12 are in contact with the ground S, a pair of capacitor electrodes 30A of either the legs 21, 24 of the first split part 11 or the legs 25, 28 of the second split part 12 are brought close to the soil E of the ground S as a pair of current electrodes, and an alternating voltage is applied between the pair of current electrodes, so that an alternating current flows through the soil E of the ground S. A pair of capacitor electrodes 30A of the other of the legs 21, 24 of the first split part 11 and the legs 25, 28 of the second split part 12 are brought close to the soil E of the ground S as a pair of potential electrodes, and the potential between the pair of potential electrodes is measured.

[0049] When a voltage is applied to the conductor 32 of a pair of current electrodes brought close to the ground S, charges accumulate between the dielectric 31 and the soil E of the ground S, and the current electrodes become capacitors. If the polarity of the voltage is switched before the capacitor - formed current electrodes are fully charged or discharged, an alternating current continuously flows through the soil E having a resistance value. On the other hand, the potential of a pair of potential electrodes that have become capacitors in the same way as the current electrodes is measured. From the value of the current of the current electrodes and the value of the potential of the potential electrodes, the specific resistance of the soil E of the ground S is measured. The same applies when the legs 22, 23 of the first split part 11 and the legs 26, 27 of the second split part 12 are in contact with the ground S.

[0050] By changing the distance between the first split part 11 and the second split part 12, the depth from the ground S of the soil E for which the specific resistance is measured can be changed. Also, by changing the interval (stride) between each of the legs 21, 24, legs 22, 23, legs 25, 28, and legs 26, 27 that are in contact with the ground S together in each of the first split part 11 and the second split part 12, the depth from the ground S of the soil E for which the specific resistance is measured can be changed. Note that the second split part 12 may run parallel to the first split part 11. From the specific resistance at each position measured by the electrode part 20A, the dry density or wet density of the soil having a correlation with the specific resistance is derived. Thereby, the quality of the soil on the ground at each position can be evaluated, and the effect of compaction by the compaction machine can be confirmed.

[0051] According to this embodiment, in the resistivity measuring device 1A including a main body 10A that moves on the ground S and an electrode part 20A that is close to the ground S from the main body 10A and measures the resistivity of the soil E of the ground S, the electrode part 20A repeatedly approaches and separates from the ground S, and measures the resistivity of the soil E of the ground S when it is close to the ground S. Therefore, compared with the case where the electrode and the ground are always in contact during the running of the vehicle, the measured value of the resistivity of the soil E of the ground S is less likely to vary due to the unevenness of the ground S. Thus, it is possible to measure the resistivity of the soil E of the ground S while moving while reducing the influence of the unevenness of the ground S.

[0052] Further, according to this embodiment, the electrode part 20A has a plurality of leg parts 21 and the like that repeatedly contact and separate from the ground S to move the main body 10A on the ground S by walking. Since the resistivity of the soil E of the ground S is measured when the leg parts 21 and the like contact the ground S, it is possible to move on the ground S without always contacting the electrode part 20A and the ground S.

[0053] Further, according to this embodiment, the main body 10A has a first split part 11 and a second split part 12 separated from the first split part 11. The electrode part 20A has four pairs of leg parts 21, 22, 23, 24, 25, 26, 27, 28. One two pairs of leg parts 21, 22, 23, 24 among the four pairs of leg parts 21, 22, 23, 24, 25, 26, 27, 28 are arranged on the first split part 11, and the first split part 11 is moved on the ground S by repeatedly contacting and separating from the ground S and walking. The other two pairs of leg parts 25, 26, 27, 28 among the four pairs of leg parts 21, 22, 23, 24, 25, 26, 27, 28 are arranged on the second split part 12, and the second split part 12 is moved on the ground by repeatedly contacting and separating from the ground S and walking. Since the first split part 11 and the second split part 12 can each move on the ground S by four-legged walking, the structure of each of the first split part 11 and the second split part 12 can be simplified, and each of the first split part 11 and the second split part 12 can be made small.

[0054] Further, one pair of two legs 21, 22, 23, 24 arranged on the first body part 11 and the other pair of two legs 25, 26, 27, 28 arranged on the second body part 12 repeatedly make contact with and separate from the ground S in synchronization with each other to walk. When two legs 21, 24 or legs 22, 23 among one pair of two legs 21, 22, 23, 24 arranged on the first body part 11 and two legs 25, 28 or legs 26, 27 among the other pair of two legs 25, 26, 27, 28 arranged on the second body part 12 come into contact with the ground S, the electrode part 20A measures the specific resistance of the soil E of the ground S. For example, by changing the distance between the first body part 11 and the second body part 12, the depth from the ground S of the soil E for which the specific resistance is measured can be changed. Further, since the first body part 11 and the second body part 12 are robots that move on the ground S by four-legged walking under autonomous control, the measurement of the resistivity of the soil E of the ground S is made unmanned and labor-saving.

[0055] Further, according to the present embodiment, a measurement management unit 50 that manages the value of the specific resistance of the soil E of the ground S measured by the electrode unit 20A deletes the value of the specific resistance of the soil E of the ground S measured by the electrode unit 20A when the time difference between the times when each of the plurality of legs 21, etc. comes into contact with the ground S is larger than a threshold value and it is expected that the accuracy of the value of the specific resistance measured by the electrode unit 20A is low, so that only the value of the specific resistance with high measurement accuracy can be left.

[0056] Further, according to the present embodiment, the electrode unit 20A has a capacitor electrode 30A including a dielectric 31 facing the ground S and a conductor 32 connected to the dielectric 31. The dielectric 31 repeatedly approaches and separates from the ground S, and when the dielectric 31 approaches the ground S, the electrode unit 20A measures the specific resistance of the soil E of the ground S. Since the capacitor electrode 30A can measure the specific resistance of the soil E of the ground S only by bringing the dielectric 31 closer to the ground S, the influence of unevenness of the ground S can be further reduced.

[0057] Further, according to the present embodiment, the electrode portions 20A, 20B, and 20C have opposing surfaces 40A, 40B, and 40C that face the ground S. The opposing surfaces 40A, 40B, and 40C include contact surfaces 41A, 41B, and 41C that contact the ground S and non-contact surfaces 42A, 42B, and 42C that do not contact the ground S. The contact surfaces 41A, 41B, and 41C are constituted by either a plane parallel to the ground S or a curved surface protruding with respect to the ground S. The contact surfaces 41A, 41B, and 41C and the non-contact surfaces 42A, 42B, and 42C are connected by a curved surface. The contact surfaces 41A, 41B, and 41C repeat contact with and separation from the ground S. When the contact surfaces 41A, 41B, and 41C contact the ground S, the electrode portions 20A, 20B, and 20C measure the specific resistance of the soil E of the ground S. Therefore, for example, while reducing the disturbance of the ground S after the embankment is compacted by a compactor, the specific resistance of the soil E of the ground S can be measured while moving.

[0058] Further, according to the present embodiment, since the storage unit 62 stores the value of the specific resistance of the soil E of the ground S measured by the electrode portion 20A and the position of the main body portion 10A measured by the positioning unit 61 in an associated manner, it is easy to grasp the relationship between the position and the specific resistance of the soil E of the ground S at that position.

[0059] Hereinafter, the specific resistance measurement device and the specific resistance measurement method according to the second embodiment of the present invention will be described. As shown in FIG. 4, in the specific resistance measurement device 1B of the present embodiment, the main body portion 10B has a moving portion 70 that moves the main body portion 10B on the ground S. The moving portion 70 moves the main body portion 10A on the ground S by, for example, wheels or an endless track. In the present embodiment, the main body portion 10B is integrated and does not have the first split portion 11 and the second split portion 12 as in the first embodiment.

[0060] In the specific resistance measuring device 1B of this embodiment, when the main body 10B is moved on the ground S by the moving unit 70, the two pairs of electrode units 20D repeatedly approach and separate from the ground S, and measure the specific resistance of the soil E on the ground S when approaching the ground S. In the example of FIG. 4, each of the two pairs of electrode units 20D repeatedly approaches and separates from the ground S from the main body 10B while being synchronized with each other by a mechanism capable of advancing and retracting the tip with respect to the ground S. When the two pairs of electrode units 20D contact the ground S, the electrode units 20D measure the specific resistance of the soil E on the ground S. Each of the electrode units 20D has a capacitor electrode 30D composed of a flat dielectric 31 facing the ground and a flat conductor 32 connected to the dielectric 31.

[0061] In this embodiment, for example, one pair of either of the capacitor electrodes 30D of the two pairs of electrode units 20D is brought close to the soil E on the ground S as a pair of current electrodes, and an alternating voltage is applied between the pair of current electrodes to cause an alternating current to flow through the soil E on the ground S. Also, the other pair of either of the capacitor electrodes 30D of the two pairs of electrode units 20D is brought close to the soil E on the ground S as a pair of potential electrodes, and the potential between the pair of potential electrodes is measured. For example, by changing the interval between each of the electrode units 20D, the depth from the ground S of the soil E for which the specific resistance is measured can be changed. When the interval between the two inner electrodes among the capacitor electrodes 30D of the electrode unit 20D, which are four electrodes, is na, and the interval between the other two adjacent capacitor electrodes 30D is a, the point at which the measurement depth becomes a(n + 1) / 2 is the same as in the first embodiment described above.

[0062] According to the present embodiment, the main body 10B has a moving part 70 for moving the main body 10B on the ground S. When the main body 10B is moved on the ground S by the moving part 70, the electrode part 20D repeatedly approaches and separates from the ground S, and measures the specific resistance of the soil E of the ground S when approaching the ground S. Therefore, the electrode part 20D can move on the ground S without always contacting the ground S. Further, in the present embodiment, since the electrode part 20D does not contribute to the movement of the main body 10B, it is not always necessary to bring the electrode part 20D into contact with the ground S, and the disturbance of the ground S after the embankment is compacted by the roller can be reduced. Further, since the moving part 70 can be formed of wheels or the like, the configuration of the moving part 70 can be simplified.

[0063] As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above embodiments and can be implemented in various forms. For example, in the specific resistance measuring device 1A of the first embodiment, the first split part 11 and the second split part 12 may be integrated with each other, and the integrated main body 10A may have four pairs of legs 21, 22, 23, 24, 25, 26, 27, 28. According to this configuration, the specific resistance measuring device 1A can be integrated and operated. In this case, by changing the intervals between the legs 21, 24, etc. that come into contact with the ground S together, the depth from the ground S of the soil E for measuring the specific resistance can be changed. Further, the main body 10A may include nine or more legs 21 or the like.

[0064] Further, in the specific resistance measuring device 1B of the second embodiment, like the specific resistance measuring device 1A of the first embodiment, the first split part 11 and the second split part 12 having a pair of electrode parts 20D may be provided. According to this configuration, the structure of each of the first split part 11 and the second split part 12 can be simplified, and each of the first split part 11 and the second split part 12 can be made small. In this case, similar to the first embodiment, by changing the distance between the second split part 12 and the first split part 11, the depth from the ground S of the soil E for measuring the specific resistance can be changed. Further, the main body 10B may include five or more electrode parts 20D.

[0065] In addition, the shapes and configurations of the electrode portions 20A, 20B, 20C, and 20D can be changed as appropriate. Also, the electrode portions 20A, 20B, 20C, and 20D do not necessarily have to have the capacitor electrodes 30A, 30B, 30C, and 30D. Further, the specific resistance measuring devices 1A and 1B may be integrated with a vibrating roller or the like. The soil E for which the specific resistance is measured by the specific resistance measuring devices 1A and 1B includes not only general soil E but also materials in which cement is added and mixed to gravel and the like obtained at a construction site in the CSG (Cemented Sand and Gravel) method and materials in which superplasticized concrete with a reduced amount of cement in the RCD (Roller Compacted Dam - Concrete) method is spread evenly and compacted with a vibrating roller or the like.

Explanation of Reference Numerals

[0066] 1A, 1B... specific resistance measuring devices, 10A, 10B... main body portions, 11... first divided portion, 12... second divided portion, 20A, 20B, 20C, 20D... electrode portions, 21, 22, 23, 24, 25, 26, 27, 28... legs, 30A, 30B, 30C, 30D... capacitor electrodes, 31... dielectric, 32... conductor, 40A, 40B, 40C... opposing surfaces, 41A, 41B, 41C... contact surfaces, 42A, 42B, 42C... non - contact surfaces, 50... measurement management portion, 61... positioning portion, 62... storage portion, 70... moving portion, S... ground, E... soil.

Claims

1. A main body that moves on the ground, and an electrode unit that is close to the ground from the main body and measures the specific resistance of the soil on the ground. The electrode unit repeatedly approaches and separates from the ground, and measures the specific resistance of the soil on the ground when it is close to the ground. The electrode unit has a plurality of legs that repeatedly contact and separate from the ground to move the main body on the ground by walking, and measures the specific resistance of the soil on the ground when the legs contact the ground. The main body has a first split part and a second split part separated from the first split part. The electrode unit has four pairs of the legs. One of the two pairs of the four pairs of legs is arranged on the first split part, and the first split part is moved on the ground by repeatedly contacting and separating from the ground to walk. The other two pairs of the four pairs of legs are arranged on the second split part, and the second split part is moved on the ground by repeatedly contacting and separating from the ground to walk. The one of the two pairs of legs arranged on the first split part and the other two pairs of legs arranged on the second split part repeatedly contact and separate from the ground in synchronization to walk. When two of the two pairs of legs arranged on the first split part and two of the two pairs of legs arranged on the second split part contact the ground, the electrode unit measures the specific resistance of the soil on the ground. Specific resistance measuring device.

2. A main body that moves on the ground, and an electrode unit that is close to the ground from the main body and measures the specific resistance of the soil on the ground. The electrode unit repeatedly approaches and separates from the ground, and measures the specific resistance of the soil on the ground when it is close to the ground. The electrode unit has a plurality of legs that repeatedly contact and separate from the ground to move the main body on the ground by walking, and measures the specific resistance of the soil on the ground when the legs contact the ground. The electrode unit further includes a measurement management unit that manages the value of the specific resistance of the soil on the ground measured by the electrode unit. ​ ​ The resistivity measurement device, wherein the measurement management unit deletes the value of the specific resistance of the soil on the ground measured by the electrode unit when the difference in the contact time of each of the plurality of legs with the ground is greater than a threshold value.

3. The electrode unit has a capacitor electrode composed of a dielectric facing the ground and a conductor connected to the dielectric. The dielectric repeatedly approaches and separates from the ground, and when the dielectric approaches the ground, the electrode unit measures the specific resistance of the soil on the ground. The resistivity measurement device according to claim 1 or claim 2.

4. The electrode unit has a facing surface facing the ground, The facing surface includes a contact surface that contacts the ground and a non-contact surface that does not contact the ground, The contact surface is constituted by either a plane parallel to the ground or a curved surface protruding with respect to the ground, The contact surface and the non-contact surface are connected by a curved surface, The contact surface repeatedly contacts and separates from the ground, and when the contact surface contacts the ground, the electrode unit measures the specific resistance of the soil on the ground. The resistivity measurement device according to any one of claims 1 to 3.

5. A positioning unit for positioning the position of the main body unit, A storage unit for associating and storing the value of the specific resistance of the soil on the ground measured by the electrode unit and the position of the main body unit measured by the positioning unit. The resistivity measurement device according to any one of claims 1 to 4.

6. A moving step in which the main body unit moves on the ground, A specific resistance measurement step in which an electrode unit approaching the ground from the main body unit measures the specific resistance of the soil on the ground, Comprising, In the specific resistance measurement step, the electrode unit repeatedly approaches and separates from the ground, and measures the specific resistance of the soil on the ground when approaching the ground, The electrode unit has a plurality of legs that repeatedly contact and separate from the ground and walk to move the main body unit on the ground. When the legs contact the ground, the specific resistance of the soil on the ground is measured, The main body unit has a first split part and a second split part separated from the first split part, The electrode unit has four pairs of the legs, One of the two pairs of the four pairs of legs is arranged on the first split part, and repeatedly contacts and separates from the ground and walks to move the first split part on the ground, The other two pairs of the four pairs of the legs are arranged on the second split part, and the second split part is moved on the ground by repeatedly contacting and separating from the ground while walking, One two pairs of the legs arranged on the first split part and the other two pairs of the legs arranged on the second split part repeatedly walk in synchronization with each other by contacting and separating from the ground, When two of the legs of one two pairs of the legs arranged on the first split part and two of the legs of the other two pairs of the legs arranged on the second split part contact the ground, the electrode part measures the specific resistance of the soil on the ground. Specific resistance measurement method.

7. A moving step in which the main body part moves on the ground, A specific resistance measurement step in which an electrode part close to the ground from the main body part measures the specific resistance of the soil on the ground, Comprising: In the specific resistance measurement step, the electrode part repeatedly approaches and separates from the ground, and measures the specific resistance of the soil on the ground when approaching the ground. The electrode part has a plurality of legs that move the main body part on the ground by repeatedly contacting and separating from the ground while walking, and measures the specific resistance of the soil on the ground when the legs contact the ground. Further comprising a measurement management part that manages the value of the specific resistance of the soil on the ground measured by the electrode part. When the time difference between the times when each of the plurality of legs contacts the ground is greater than a threshold value, the measurement management part deletes the value of the specific resistance of the soil on the ground measured by the electrode part. Specific resistance measurement method.

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