JP2006126108A - Water leakage detecting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water leakage detecting method capable of accurately detecting a leakage position of water in an impervious layer. <P>SOLUTION: The water leakage detecting method detects the leakage position of water in an impervious sheet 3 (impervious layer) which partitions an internal soil 4 (internal structure) and an external soil 2 (external structure). A plurality of electric potential measuring electrodes 10 and an internal electrode 13 are disposed in the internal soil 4, and an external electrode 14 is disposed in the external soil 2. A potential difference which is produced, when energizing across one electric potential measuring electrode 10a and the internal electrode 13, at another electric potential measuring electrode 10b, is subtracted from a potential difference which is produced at the another electric potential measuring electrode 10b when energizing across the electric potential measuring electrode 10a and the external electrode 14, thereby obtaining a measurement electrical potential of the another electric potential measuring electrode 10b. Operations of obtaining measurement electrical potentials are repeated at respective electric measuring electrodes 10, and the leakage position of water in the impervious sheet 3 is detected from an electric potential distribution obtained on the basis of the measurement electrical potentials of the electric measuring electrodes 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water leakage detection method for detecting a water leakage position of a water shielding layer in a water shielding structure divided into an internal structure and an external structure with a water shielding layer as a boundary.

  As a water leakage detection method for detecting the water leakage position of the water shielding sheet (water shielding layer) provided at the boundary between the internal soil (internal structure) and the external soil (external structure), an internal electrode provided in the internal soil, Each potential measurement electrode is measured by energizing between the external electrodes provided on the external soil and measuring the potential difference between the multiple potential measurement electrodes provided on the internal soil and the reference electrode provided on the external soil. There is a method of obtaining a potential, creating a potential distribution of the internal soil based on each measured potential, and detecting the water leakage position of the water shielding sheet from the distortion of the potential distribution (see, for example, Patent Document 1).

  Here, when the detection method described above is applied to soil having a high specific resistance of the internal soil, such as a disposal site before the start of landfilling, the internal electrode fixed to the internal soil by the specific resistance, and the internal electrode The potential drop between the far away place becomes large, and the voltage is hardly applied to the front and back of the water shielding sheet at the far place from the internal electrode. For this reason, even if the water shielding sheet is damaged and a hole is opened, the current passing through the hole hardly flows, and the potential distribution distortion caused by this current does not occur. There is a problem that it is difficult to detect the position.

Therefore, each of the potential measurement electrodes provided in the internal soil and the external electrode provided in the external soil are energized, and the potential difference between each potential measurement electrode and the reference electrode provided in the external soil is measured. Thus, there is a method of obtaining the measurement potential of each potential measurement electrode, creating a potential distribution of the internal soil based on each measurement potential, and detecting the leakage position of the water shielding sheet from the distortion of the potential distribution.
In this detection method, the power supply position to the internal soil and the measurement position of the measurement potential are the same, so the measurement potential of each potential measurement electrode can be obtained without considering the potential drop due to the specific resistance of the internal soil. it can.

  When a copper potential measurement electrode having a diameter of about 10 cm is used, the ground resistance of the potential measurement electrode varies between several Ω to several tens of thousands Ω. At this time, considering that the resistance value at the water leakage position of the water shielding sheet is several tens of Ω to several thousand Ω, in the detection method in which the power feeding position to the internal soil is the same as the measurement potential measurement position, Since the ground resistance of the potential measuring electrode greatly affects the measurement result, there is a problem that the water leakage position cannot be detected accurately.

Therefore, as shown in FIG. 6, two potential measuring electrodes 10b and 10c are linearly arranged at equal intervals with respect to the potential measuring electrode 10a to be measured, and the potential measuring electrode 10a and the potential measuring electrode 10c There is a detection method for obtaining a potential drop due to the ground resistance of the potential measurement electrode 10a by measuring the potential difference between the potential measurement electrode 10a and the potential measurement electrode 10b. 2).
In this detection method, by removing the potential drop due to the ground resistance from the measured potential, a measurement potential that eliminates the influence of the ground resistance is obtained, and the potential distribution of the internal soil 4 is obtained from the measured potential to determine the leakage position of the impermeable sheet 3. Is detected.
Japanese Examined Patent Publication No. 6-63901 (page 2, left column, line 50 to right column, line 6, line 1) JP 2001-330531 (paragraph 0012, FIG. 1, FIG. 2)

However, since the ground resistance of the potential measurement electrode may be a value that is much larger than the resistance value at the water leakage position of the water-impervious sheet 3, when the current is applied between the potential measurement electrode 10a and the potential measurement electrode 10c. Therefore, it is necessary to accurately measure the potential difference between the potential measuring electrode 10a and the potential measuring electrode 10b and accurately grasp the potential drop due to the ground resistance.
Therefore, in the detection method described above, the potential measurement electrode 10b is installed at an intermediate position between the potential measurement electrode 10a and the potential measurement electrode 10c, and the specific resistance conditions between the potential measurement electrodes 10a, 10b, and 10c are made uniform. There is a need. For example, when the potential measurement electrode 10b is not disposed at the intermediate position between the potential measurement electrode 10a and the potential measurement electrode 10c, and the potential measurement electrode 10b is closer to the potential measurement electrode 10a than the intermediate position, the actual ground resistance When the potential measuring electrode 10b is far from the intermediate position, the potential difference is larger than the actual potential difference due to the ground resistance.

  In addition, when the potential measurement electrode 10a and the potential measurement electrode 10c are energized, the equipotential lines of the potential measurement electrode 10a and the potential measurement electrode 10c are linear axes that connect the potential measurement electrode 10a and the potential measurement electrode 10c. Since it is distorted in the axial direction, when the potential measuring electrodes 10a, 10b, and 10c are not arranged on a straight line, it becomes difficult to accurately measure the potential difference due to the ground resistance due to the influence of the distortion.

  Furthermore, when the potential measurement electrode 10a is close to the edge of the internal soil, the potential distribution is distorted due to the influence of the edge of the internal soil, so the potential measurement electrodes 10a, 10b, and 10c are linearly spaced at equal intervals. Even if it is disposed above, there is a problem that it becomes difficult to accurately measure the potential difference due to the ground resistance due to the influence of the distortion.

As described above, in the detection method described above, the three potential measurement electrodes 10a, 10b, and 10c need to be linearly arranged at equal intervals, but when the shape of the internal soil 4 is complicated, the internal soil It is difficult to arrange all the potential measurement electrodes 10 provided in 4 linearly at equal intervals.
Therefore, in the above-described detection method, it is difficult to arrange the potential measurement electrodes 10a, 10b, and 10c linearly at equal intervals because of the influence of the shape of the internal soil, and thus the potential due to the ground resistance of the potential measurement electrode 10a. Since it is difficult to accurately grasp the descent and it is difficult to remove the influence of the ground resistance and create a potential distribution, there is a problem that the detection accuracy of the water leakage position in the water shielding sheet 3 is lowered. is there.

  Therefore, in the present invention, the above-described problems are solved, and the influence of the grounding resistance of the potential measurement electrode is removed without being affected by the shape of the internal structure, the interval between the potential measurement electrodes, or the position. It is an object of the present invention to provide a water leakage detection method capable of obtaining a potential distribution and accurately detecting a water leakage position of a water shielding layer from the potential distribution.

  In order to solve the above-mentioned problem, the invention described in claim 1 is a water leakage detection method for detecting a water leakage position of a water shielding layer that separates an internal structure and an external structure. The external structure is provided with an external electrode, the external structure or the internal structure is provided with a reference electrode, the one potential measurement electrode and the external electrode, From the potential difference generated between the other potential measurement electrode and the reference electrode, when the current is applied between the other potential measurement electrode and the reference electrode, By subtracting the potential difference generated between the two potential measurement electrodes, the measurement potentials of the other potential measurement electrodes are obtained. By repeating the calculation of the measurement potential at each potential measurement electrode, the measurement potential at each potential measurement electrode is obtained and Potential distribution It is characterized in that to detect the water leakage position of the water shield layer.

  Here, the shape and material of each electrode are not limited, and various existing electrodes can be used. In addition, the connection between the electrodes and the energization are performed by an existing method, and the potential difference is also measured using an existing potential meter.

As described above, in the water leakage detection method of the present invention, when one current measurement electrode and the external electrode are energized, one potential measurement electrode is obtained from a potential difference generated between the other potential measurement electrode and the reference electrode. By subtracting the potential difference generated between the other potential measurement electrode and the reference electrode when energized between the electrode and the internal electrode, the measurement potential of the other potential measurement electrode that is the measurement target is obtained.
Note that the potential difference generated in the other potential measurement electrodes is measured by a potential meter connected to the other potential measurement electrodes. At this time, since the current hardly flows through the other potential measurement electrodes due to the internal resistance of the potentiometer, it is not necessary to consider the ground resistance of the other potential measurement electrodes.
In addition, the distance between the one potential measurement electrode that is energized and the other potential measurement electrode that is the object of measurement is close to the other potential measurement electrode so that the measurement potential is not greatly affected by the specific resistance of the internal structure. It is preferable to select one potential measuring electrode provided in the above.

Thereby, in the water leakage detection method of the present invention, when a potential measurement electrode is energized, a potential difference generated between another potential measurement electrode and a reference electrode is measured. Even if it is high, the influence of the potential drop due to the specific resistance is reduced, and an accurate potential distribution can be easily obtained.
Furthermore, when determining the measurement potential of the potential measurement electrode, it is possible to determine the measurement potential from which the influence of the ground resistance is removed without determining the ground resistance of the potential measurement electrode by another operation. Therefore, it is not necessary to arrange a plurality of potential measuring electrodes in a straight line at equal intervals, and the potential measuring electrodes are not affected by the shape of the internal structure, the interval or position where each potential measuring electrode is arranged, or the like. It is possible to easily obtain the potential distribution from which the influence of the ground resistance is removed.
In the potential distribution thus obtained, the potential distortion at the water leakage position of the water shielding layer is clearly shown.

  The invention according to claim 2 is the water leakage detection method according to claim 1, wherein the water shielding layer is a double layer composed of a first layer and a second layer, and the external electrode is It is provided in an interlayer portion between the first layer and the second layer, and is characterized by detecting the water leakage position of the first layer from the potential distribution.

  As described above, in the water leakage detection method of the present invention, the external electrode is provided in the interlayer portion between the first layer and the second layer, so that it is based on the measured potential caused by the current passed through the first layer. Since the potential distribution can be created, the leak position of the first layer can be detected.

  The invention according to claim 3 is an invention related to claim 1, and is a water leakage detection method for detecting a water leakage position of a water shielding layer that separates an internal structure and an external structure, The layer is a double layer composed of a first layer and a second layer, and a plurality of potential measurement electrodes and interlayer electrodes are provided in an interlayer portion between the first layer and the second layer, and the internal structure An internal electrode is provided on the object, an external electrode is provided on the external structure, and a reference electrode is provided on the external structure, the internal structure, or the interlayer part. When a current is applied between one potential measurement electrode and an interlayer electrode, the other potential measurement electrode and the reference electrode are connected due to a potential difference generated between the other potential measurement electrode and the reference electrode. By subtracting the potential difference generated with the electrode, the first measurement potential of the other potential measurement electrode When a current is applied between one potential measurement electrode and an external electrode, a current difference is generated between the other potential measurement electrode and the reference electrode. In addition, the second measurement potential of the other potential measurement electrodes is obtained by subtracting the potential difference generated between the other potential measurement electrodes and the reference electrode, and the calculation of the first measurement potential is repeated at each potential measurement electrode. The first measurement potential at each potential measurement electrode is obtained, and the leak position of the first layer is detected from the first potential distribution obtained based on each first measurement potential, and at each potential measurement electrode, By repeating the calculation of the second measurement potential, the second measurement potential at each potential measurement electrode is obtained, and the water leakage position of the second layer is obtained from the second potential distribution obtained based on each second measurement potential. It is characterized by detecting That.

  As described above, in the water leakage detection method of the present invention, the first potential distribution created based on the first measured potential based on the current passed through the first layer and the current supplied through the second layer. Since the leak position of the first layer and the second layer can be detected separately by obtaining the second potential distribution created based on the second measured potential by the measured current, it is formed in a double layer It is possible to accurately grasp the leakage of the water shielding layer.

According to such a water leakage detection method, when a current is applied between one potential measurement electrode and an external electrode, the potential difference between the other potential measurement electrode and the reference electrode is used to determine whether the one potential measurement electrode and the internal electrode are internal. Since the measured potential of the other potential measurement electrode that is the object of measurement is obtained by subtracting the potential difference that occurs between the other potential measurement electrode and the reference electrode when energized with the electrode, the internal structure Even when the specific resistance is high, the influence of the potential drop due to the specific resistance is reduced, and an accurate potential distribution can be easily obtained.
Furthermore, the measurement potential from which the influence of the ground resistance is removed can be obtained without obtaining the ground resistance of another potential measurement electrode by another operation. This eliminates the need for linearly arranging a plurality of potential measurement electrodes at equal intervals, and without affecting the shape of the internal structure, the interval or position where each potential measurement electrode is disposed, and the like. It is possible to easily obtain a potential distribution that eliminates the influence of. In the potential distribution thus obtained, the potential distortion at the water leakage position of the water shielding layer is clearly shown, so that the water leakage position of the water shielding layer can be accurately detected.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In the description of each embodiment, the same constituent elements are denoted by the same reference numerals, and redundant descriptions are omitted.

[First Embodiment]
First, a first embodiment of the present invention will be described.
FIG. 1 is a side sectional view showing an outline of each component used in the water leakage detection method of the first embodiment. FIG. 2 is a plan view showing an outline of each component used in the water leakage detection method of the first embodiment.
The water leakage detection method of the present invention can be applied to water-impervious structures such as landfills and reservoirs for general waste or industrial waste. In the first embodiment, a water-impervious sheet ("water-impervious layer" in the claims) ) On the inside soil (landfill waste, protective soil, cover soil, etc.) that is treated soil ("internal structure" in the claim) and external soil ("external structure" in the claim) A description will be given by taking as an example a case where the present invention is applied to a buried land divided into two.

First, each component used for the water leak detection method of 1st Embodiment is demonstrated.
As shown in FIGS. 1 and 2, the landfill 1 has a water shielding sheet 3 laid on the bottom and side surfaces of the excavation area provided in the external soil 2, and the internal soil 4 is deposited on the water shielding sheet 3. By doing so, the internal soil 4 and the external soil 2 are separated with the water shielding sheet 3 as a boundary.

  The water shielding sheet 3 is a sheet having a large electric resistance, and the material and thickness thereof are not limited. For example, a rubber sheet can be used.

Further, in the internal soil 4, copper potential measuring electrodes 10 are provided at intervals of 10 m to 20 m near the upper portion of the water shielding sheet 3. In addition, each electric potential measurement electrode 10 ... provided in the upper vicinity of the water shielding sheet 3 may be in contact with the upper surface of the water shielding sheet 3.
Further, in the first embodiment, the potential measuring electrodes 10 are arranged at regular intervals in a grid pattern, but it is not necessary to arrange the potential measuring electrodes 10 linearly at regular intervals. These can be arranged in correspondence with the shape of the landfill 1 and the number thereof is not limited.

  Each potential measuring electrode 10 is connected to the power supply scanner 11 by an electric wire. In addition, the power supply scanner 11 is connected to an AC power supply 12 by an electric wire, and is configured to connect a specific potential measurement electrode 10 and the AC power supply 12 by switching the contact of the power supply scanner 11.

Further, in the internal soil 4, a copper internal electrode 13 is provided in the vicinity of the upper portion of the water shielding sheet 3, and a copper external electrode 14 is embedded in the external soil 2.
The AC power supply 12 is connected to the internal electrode 13 and the external electrode 14 by an electric wire via the changeover switch 15, and the AC power supply 12 and the internal electrode 13 or the external electrode 14 are switched by switching the contacts of the changeover switch 15. And are configured to be connected.

  Furthermore, each potential measurement electrode 10... Is connected to the measurement scanner 16 by an electric wire. On the other hand, a copper reference electrode 17 is embedded in the external soil 2, and the measurement scanner 16 is connected to the reference electrode 17 by an electric wire. The specific potential measurement electrode 10 and the reference electrode 17 are connected by switching the contact of the measurement scanner 16. Further, a potential measuring meter 18 is interposed between the measurement scanner 16 and the reference electrode 17, and a potential difference between each potential measuring electrode 10 ... and the reference electrode 17 can be measured.

  1 and 2 simplify the respective components used in the water leakage detection method of the first embodiment, and the power supply scanner 11 has a specific potential measurement electrode 10a (hereinafter referred to as “one potential measurement electrode”). , And the measurement scanner 16 is connected to a specific potential measurement electrode 10b (hereinafter referred to as “other potential measurement electrode”), and each of the other potential measurement electrodes 10. Connection with the scanner 11 or the measurement scanner 16 is omitted.

Next, a water leakage detection method using each of the above-described components will be described.
(Potential measurement process)
First, the contact of the power supply scanner 11 is switched to connect the one potential measurement electrode 10 a and the AC power supply 12, and the contact of the changeover switch 15 is switched to connect the AC power supply 12 and the external electrode 14.
Further, the contact of the measurement scanner 16 is switched to connect the other potential measurement electrode 10 b to be measured and the reference electrode 17.
At this time, it is preferable to select the potential measurement electrode 10a provided closest to the other potential measurement electrode 10b to be measured as the one potential measurement electrode 10a connected to the power supply scanner 11.

Subsequently, the AC power supply 12 is caused to generate power, and the external electrode 14 is energized from the single potential measurement electrode 10a through the water shielding sheet 3 and the external soil 2, so that the potential measurement electrode 10a and the external electrode 14 are electrically connected. Energize to.
On the other hand, the potential difference generated between the other potential measurement electrode 10 b and the reference electrode 17 by the power generation of the AC power supply 12 is measured by the potential measurement meter 18.

Furthermore, after the power generation of the AC power supply 12 is stopped, the AC power supply 12 and the internal electrode 13 are connected by switching the contact of the changeover switch 15. And it supplies with electricity between the one electric potential measurement electrode 10a and the internal electrode 13 by making the alternating current power supply 12 generate electric power, and making the internal electrode 13 pass electricity through the internal soil 4 from the one electric potential measurement electrode 10a.
On the other hand, the potential difference generated between the other potential measurement electrode 10 b and the reference electrode 17 by the power generation of the AC power supply 12 is measured by the potential measurement meter 18.

  As described above, when a current is applied between one potential measurement electrode 10a and the external electrode 14, the potential difference generated between the other potential measurement electrode 10b and the reference electrode 17, and the one potential measurement electrode 10a and the internal Even when the specific resistance of the internal soil 4 is high by measuring the potential difference generated between the other potential measurement electrode 10b and the reference electrode 17 when energized with the electrode 13, the specific resistance The effect of potential drop due to is reduced.

Then, from the potential difference generated between the other potential measurement electrode 10b and the reference electrode 17 when energized between the one potential measurement electrode 10a and the external electrode 14, the one potential measurement electrode 10a and the internal electrode 13 are obtained. By subtracting the potential difference generated between the other potential measurement electrode 10b and the reference electrode 17 when the current is supplied between the first and second potential measurement electrodes 10b, the measurement potential of the other potential measurement electrode 10b is obtained.
At this time, almost no current flows between the other potential measurement electrode 10b and the reference electrode 17 due to the internal resistance of the potential meter 18, and therefore, the potential difference between the other potential measurement electrode 10b and the reference electrode 17 is reduced. The measurement result is not affected by the ground resistances of the other potential measurement electrodes 10b and the reference electrode 17.

  Thus, when measuring the measurement potential of the other potential measurement electrode 10b that is the measurement target, the measurement potential from which the influence of the ground resistance is removed without obtaining the ground resistance of the other potential measurement electrode 10b by another operation. Can be requested. This eliminates the need for linearly arranging a plurality of potential measuring electrodes 10... At the same interval, so that the shape of the internal soil 4, the interval or position at which each potential measuring electrode 10. Without being influenced, it is possible to easily obtain the measurement potential from which the influence of the ground resistance of the potential measurement electrode 10 is removed.

(Potential distribution creation process)
Moreover, the measurement potential in each potential measurement electrode 10... Is obtained by repeating the potential measurement process for the plurality of potential measurement electrodes 10.
Thereafter, a potential distribution of the internal soil 4 is created based on each measured potential. At this time, when there is a water leakage location on the water shielding sheet 3, since the potential distribution at the water leakage position is distorted, the water leakage position of the water shielding sheet 3 is specified from the distorted position. In particular, in the present invention, the influence of the ground resistance of the potential measurement electrode 10 is removed from the potential distribution, and power can be supplied in the vicinity of the water leakage position, and the potential distortion at the water leakage position of the water shielding sheet 3 is clearly shown. For this reason, the water leakage position of the water shielding sheet 3 can be accurately specified.

Therefore, in the water leakage detection method of the present invention, a plurality of potential measurement electrodes 10... Are linearly arranged at equal intervals, and the ground resistance is determined without determining the ground resistance of the potential measurement electrode 10 to be measured. The measurement potential from which the influence has been removed can be obtained. In this way, the potential distribution in which the influence of the ground resistance of the potential measuring electrode 10 is removed is simplified without being affected by the shape of the internal soil 4, the interval at which the potential measuring electrodes 10 are arranged, or the position. Can be requested.
Further, even when the water shielding sheet 3 is damaged and a hole is formed and water leakage occurs, the potential difference when power is supplied to the potential measuring electrode 10 closest to the water leakage position can be measured. The voltage drop from 10 to the water leakage position can be made very small, and even if the specific resistance of the internal soil 4 is high, the influence of the specific resistance is reduced, and the potential distortion due to water leakage is a large difference. I can grasp it.
In the potential distribution thus obtained, the potential distortion at the water leakage position of the water shielding sheet 3 is clearly shown, so that the water leakage position of the water shielding sheet 3 can be accurately detected.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
FIG. 3 is a side sectional view showing an outline of each component used in the water leakage detection method of the second embodiment.
The second embodiment has substantially the same configuration as the first embodiment, and the water shielding sheet is a double sheet and the arrangement of the external electrodes is different.

As shown in FIG. 3, the water-impervious sheet 3 ′ of the second embodiment is a double sheet composed of a first layer 3 a and a second layer 3 b arranged above and below at a predetermined interval. The interlayer portion 3c between the first layer 3a and the second layer 3b is in a state having conductivity. For example, conductivity can be provided by laying a conductive mat on the interlayer 3c.
Furthermore, in the second embodiment, the external electrode 14a and the reference electrode 17 are provided in the interlayer portion 3c.

Thus, in 2nd Embodiment, the interlayer part 3c between the 1st layer 3a and the 2nd layer 3b is equivalent to the external soil 2 (refer FIG. 1) in 1st Embodiment, 1st The layer 3a corresponds to the water shielding sheet 3 (see FIG. 1) in the first embodiment.
As a result, the potential distribution obtained in the same manner as in the first embodiment is a potential distribution created based on the measured potential caused by the current passed through the first layer 3a. Since the leak position of the first layer 3a is shown, the leak position of the first layer 3a can be easily and accurately obtained.

[Third Embodiment]
Next, a third embodiment of the present invention will be described.
FIG. 4 is a side sectional view showing an outline of each component used in the water leakage detection method of the third embodiment.
The third embodiment has substantially the same configuration as that of the first embodiment, and the water shielding sheet is a double sheet, and the arrangement of the potential measurement electrodes is different.

As shown in FIG. 4, the water shielding sheet 3 ′ of the third embodiment is a double sheet composed of a first layer 3a and a second layer 3b, and the water shielding sheet 3 of the second embodiment. The configuration is the same as'.
Furthermore, in the third embodiment, each potential measurement electrode 10... And the interlayer electrode 19 are provided in the interlayer portion 3 c between the first layer 3 a and the second layer 3 b.
The connection between the AC power source 12 and the internal electrode 13, the external electrode 14, and the interlayer electrode 19 can be switched by a changeover switch 15.

And in 3rd Embodiment, when it supplies with electricity between one electric potential measurement electrode 10a and the internal electrode 13 provided in the internal soil 4 in an electric potential measurement process, other electric potential measurement electrode 10b, the reference electrode 17, and By subtracting the potential difference generated between the other potential measurement electrode 10b and the reference electrode 17 when the current is applied between the one potential measurement electrode 10a and the interlayer electrode 19 from the potential difference generated between Obtain the measured potential.
In addition, when a current is applied between one potential measurement electrode 10a and the external electrode 14 provided on the external soil 2, one potential measurement is performed based on a potential difference generated between another potential measurement electrode 10b and the reference electrode 17. The second measurement potential is obtained by subtracting the potential difference generated between the other potential measurement electrode 10b and the reference electrode 17 when the electrode 10a and the interlayer electrode 19 are energized.

Furthermore, the first measurement potential and the second measurement potential at each potential measurement electrode 10... Are obtained by repeating the potential measurement process for each potential measurement electrode 10. Then, a first potential distribution is created based on each first measured potential, and a second potential distribution is created based on each second measured potential.
Since the first potential distribution is created based on the first measured potential based on the current passed through the first layer 3a, the leakage position of the first layer 3a is detected from the first potential distribution. can do. Similarly, since the second potential distribution is created based on the second measured potential due to the current passed through the second layer 3b, the leakage position of the second layer 3b from the second potential distribution. Can be detected.

  Thereby, in the water leak detection method of the third embodiment, the first measurement potential and the second measurement potential are respectively obtained, and the first potential distribution and the second potential that are not affected by the ground resistance of the potential measurement electrode 10 are obtained. By obtaining the distribution, the leakage position of the first layer 3a or the second layer 3b can be detected easily and accurately, and the leakage of the water shielding sheet 3 'formed in the double layer is accurately grasped. Can do.

As mentioned above, although embodiment of this invention was described, this invention is not limited to each said embodiment. For example, in the first embodiment, as shown in FIG. 1, the reference electrode 17 is provided on the external soil 2, but even when the reference electrode 17 is provided on the internal soil 4, The potential difference measured between the potential measurement electrode 10b and the reference electrode 17 is the same as the measurement value of the first embodiment.
In the second embodiment, as shown in FIG. 3, the reference electrode 17 is provided in the interlayer portion 3 c, but even if the reference electrode 17 is provided in the external soil 2 or the internal soil 4, the measurement target The potential difference measured between the other potential measurement electrode 10b and the reference electrode 17 is the same as the measurement value of the second embodiment.
Furthermore, in 3rd Embodiment, as shown in FIG. 4, although the reference electrode 17 is provided in the external soil 2, it is a case where the reference electrode 17 is provided in the internal soil 4, the external soil 2, or the interlayer part 3c. However, the potential difference measured between the other potential measurement electrode 10b to be measured and the reference electrode 17 is the same as the measurement value of the third embodiment.
Further, in the third embodiment, a plurality of reference electrodes 17 are provided at different positions, and the same applies even when different reference electrodes 17 are used in the measurement of the first layer 3a and the measurement of the second layer 3b. Result can be obtained.
In the present embodiment, power is supplied using an AC power supply. However, the power supply is not limited to this, and a DC power supply may be used. Alternatively, as shown in FIG. ) May be used.

It is the sectional side view which showed the outline of each component used for the water leak detection method of 1st Embodiment. It is the top view which showed the outline of each component used for the water leak detection method of 1st Embodiment. It is the sectional side view which showed the outline of each component used for the water leak detection method of 2nd Embodiment. It is the sectional side view which showed the outline of each component used for the water leak detection method of 3rd Embodiment. It is the conceptual diagram which showed the rectangular power supply. It is the sectional side view which showed the outline of each component used for the conventional water leak detection method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Landfill 2 External soil 3 Impermeable sheet 4 Internal soil 10 Electric potential measurement electrode 12 AC power supply 13 Internal electrode 14 External electrode 17 Reference electrode 18 Electric potential meter

Claims (3)

A water leakage detection method for detecting a water leakage position of a water shielding layer that separates an internal structure and an external structure,
The internal structure is provided with a plurality of potential measurement electrodes and internal electrodes,
The external structure is provided with external electrodes,
The external structure or the internal structure is provided with a reference electrode,
From the potential difference generated between the other potential measurement electrode and the reference electrode when energized between the one potential measurement electrode and the external electrode,
By subtracting the potential difference generated between the other potential measurement electrode and the reference electrode when energized between the one potential measurement electrode and the internal electrode, the measurement potential of the other potential measurement electrode is reduced. Seeking
By repeatedly calculating the measurement potential at each potential measurement electrode, the measurement potential at each potential measurement electrode is obtained, and the leakage position of the water shielding layer is detected from the potential distribution obtained based on each measurement potential. A water leakage detection method characterized by: The water shielding layer is a double layer composed of a first layer and a second layer,
The external electrode is provided in an interlayer portion between the first layer and the second layer;
The water leakage detection method according to claim 1, wherein the water leakage position of the first layer is detected from the potential distribution. A water leakage detection method for detecting a water leakage position of a water shielding layer that separates an internal structure and an external structure,
The water shielding layer is a double layer composed of a first layer and a second layer,
A plurality of potential measurement electrodes and interlayer electrodes are provided in an interlayer portion between the first layer and the second layer,
The internal structure is provided with an internal electrode,
The external structure is provided with external electrodes,
A reference electrode is provided on the external structure or the internal structure or the interlayer part,
From the potential difference generated between the other potential measuring electrode and the reference electrode when energized between the one potential measuring electrode and the internal electrode,
The first potential of the other potential measuring electrode is subtracted by subtracting the potential difference generated between the other potential measuring electrode and the reference electrode when energized between the one potential measuring electrode and the interlayer electrode. Find the measurement potential,
From the potential difference generated between the other potential measurement electrode and the reference electrode when energized between the one potential measurement electrode and the external electrode,
By subtracting the potential difference generated between the other potential measuring electrode and the reference electrode when energized between the one potential measuring electrode and the interlayer electrode, the second potential of the other potential measuring electrode is reduced. Find the measurement potential,
By repeating the calculation of the first measurement potential at each potential measurement electrode, the first measurement potential at each potential measurement electrode is obtained, and the first potential obtained based on each first measurement potential is obtained. From the distribution, detecting the water leakage position of the first layer,
By repeating the calculation of the second measurement potential at each potential measurement electrode, the second measurement potential at each potential measurement electrode is obtained, and the second potential obtained based on the second measurement potential is obtained. A water leak detection method comprising detecting the water leak position of the second layer from the distribution.

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