JP2002156305A - Water leak generation position detecting device and its method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water leak generation position detection device and its method, capable of distinguishing and detecting the water leak position surely, even if plural water leak locations exist, and improving accuracy for detecting the water leak generation position. SOLUTION: This water leak generation position detection device is equipped with a sealing construction structure 1 for laying a sealing construction 2 of an electrical insulator, a surface electrode 12 installed on either of the front and the back of the sealing construction 2, plural point electrodes installed on the opposite side to the surface electrode 12, a first selection connection means for setting an applicator by selecting one from the plural point electrodes and connecting the electrode to the application side of a power source 4, a potential difference measuring means 5 for measuring the potential difference between the point electrodes except the applicator by a voltage applied between the applicator and the surface electrode 12, and a second selection connection means for setting potential difference measuring electrodes by selecting two point electrodes adjacent to the application electrode and connecting the electrodes to the potential difference measuring means 5. The device is used for detecting the water leak position of the sealing construction structure 1 from the measured potential difference and the position of the applicator. The device has a third selection connection means for connecting all point electrodes, except the selected applicator and the potential difference measuring electrodes, and the surface electrode 12 to the other terminal of the power source 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reservoir, a waterway, or a managed municipal waste which is artificially constructed by laying a water shield made of an electrically insulating material such as synthetic resin or synthetic rubber. TECHNICAL FIELD The present invention relates to a water leakage occurrence position detecting device and method for detecting a water leakage occurrence position generated in a water impervious structure of a water impervious structure, such as a final disposal site and a managed industrial waste final disposal site.

[0002]

2. Description of the Related Art Water-blocking structures such as reservoirs, waterways, or managed general waste final disposal sites and managed industrial waste final disposal sites are made of electrically insulating materials such as synthetic resins and synthetic rubbers. It is constructed artificially by laying a water barrier made of pits in a depression in the ground.

[0003] In such a seepage control structure, when damage such as a crack occurs in the seepage control work, water leaks from the damaged portion to the ground side. For example, in the case of a managed municipal solid waste final disposal site, if the impermeable works are left in a damaged state, the contaminated liquid leaks and contaminates nearby areas, or contaminates groundwater, causing a pollution problem. Therefore, it is necessary to detect the occurrence and location of water leakage (or damage to the water impervious work) and repair the damaged part in the water impervious structure using the water impervious work.

Conventionally, as a method for detecting a water leaking portion of such a seepage control structure, a voltage is applied between an electrode installed inside the seepage control structure and an electrode installed on the outside ground side, and the voltage is detected. In addition to the electrodes to be applied, the potential distribution is measured by using a large number of electrodes installed on the front and back of the water shield, and the leak location is specified by detecting the potential abnormality around the water leak of the water shield. Methods are known.

[0005]

By the way, it is provided that a protective layer for preventing ultraviolet ray deterioration and thermal deterioration of the water shielding work is provided so as to cover the entire water shielding work. As a material for the protective layer and the like, a nonwoven fabric of synthetic fiber such as polyester is generally used. However, since a soil material or concrete is superior in terms of durability, a soil material or concrete is often used. . In any case, these materials such as the protective layer are not electrical insulators. Therefore, since the protective layer and the like are electrically equivalent to water leakage, even if a voltage is applied to the electrodes above and below the water shielding work, even if a potential difference abnormality occurs around the protective layer, etc. It is difficult to distinguish whether the leakage is caused by the protection layer or the like, which is an obstacle to improving the accuracy of detecting the position where the water leak has occurred. This phenomenon has the same type of measurement obstacle in the waste loading road and the leachate drainage pipe even in the conventional disposal site, and reduces the measurement accuracy. Similarly, when a plurality of water leaks occur, the potential difference overlaps due to the influence of the water leaks, making it difficult to distinguish the positions of the individual water leaks, which is an obstacle to improving the accuracy of detecting the water leak occurrence position. Had become.

In view of the above, the present invention has been made in view of the above problems, and even if there are a plurality of water leakage positions, the water leakage positions can be reliably distinguished and detected, and the accuracy of detecting the water leakage occurrence position can be improved. It is an object of the present invention to provide a water leak occurrence position detecting device and a method thereof that can improve the water leakage.

[0007]

Means for Solving the Problems In order to achieve the above object, a water leakage occurrence position detecting apparatus and method according to the present invention employs the following means. In other words, the water leakage occurrence position detecting device according to claim 1 is a water impervious structure in which a water impervious structure of an electrical insulator is laid in a depression formed in the ground, and a surface electrode installed on either side of the water impervious work. A plurality of point electrodes provided on the opposite side of the surface electrode, a first selection connection means for selecting one of the plurality of point electrodes and connecting to an application side of a power supply to make an application electrode; A potential difference measuring means for measuring a potential difference between the point electrodes excluding the electrodes, and a second selection of selecting the two point electrodes adjacent to the application electrode and connecting to the potential difference measuring means to form a potential difference measuring electrode And a connection means, comprising: a water leakage occurrence position detecting device that detects a water leakage position of the impermeable structure from the measured potential difference and the position of the application electrode, wherein the selected application electrode and the potential difference measurement electrode are provided. All point electrodes except for And having a third selective connection means for connecting the other end of the source.

According to the first aspect of the present invention, the voltage applied between the applied electrode and the plane electrode by the first selective connecting means is: (1) the first selective connecting means → applied electrode → ground → applied A point electrode other than the electrode and the potential difference measuring electrode → the other end of the power supply 4.
(2) First selective connection means → applied electrode → ground → surface electrode → other end of power supply. (3) First selective connection means → applied electrode → water leakage →
A circuit from the surface electrode to the other end of the power supply is formed.

According to the circuits (1) to (3), a voltage is applied between the one application electrode selected by the first selection connection means and the surface electrode, and the second selection connection means The potential difference is measured between the two potential difference measuring electrodes selected by the above. In addition, by the third selective connection means, all the point electrodes except the applied electrode and the potential difference measuring electrode are connected to the other end of the power source which is not the applied side, so that the electric fields on the front and back of the water shield work have the same potential. Is controlled as follows.

[0010] That is, the control of the electric potential on the front and back of the water shield works by connecting all the point electrodes except one selected application electrode and two potential difference measurement electrodes to the other end of the power supply connected to the surface electrode. This is done by connecting. If the upper and lower water shields except the applied electrode and the two potential difference measuring electrodes are controlled to have the same potential, the potential gradient is theoretically measured to be 0 V under the condition that there is no water leak around the applied electrode, A significant potential difference will be measured under the condition that there is a water leak around the application electrode. Further, the fluctuation of the potential difference is measured only around the water leak, and even if there are a plurality of water leaks, the potential differences do not overlap due to the influence of the water leak as in the related art, and the leak portion can be reliably distinguished and detected.

It is more advantageous that the point electrode has a wider area than a simple metal plate. Therefore, the point electrode can be exemplified by one in which a bare copper wire is formed in a rectangular frame shape, or one in which a bare copper wire is formed in a spiral shape to further increase sensitivity.

[0012] Examples of the water shielding work include a synthetic resin and a synthetic rubber, which are electrically insulating materials. Examples of the protective layer used in the managed waste final disposal site include a case where a nonwoven fabric (light-shielding mat) of polyester or polypropylene is laid, or a case where a soil material or concrete is laid.

[0013] In a second aspect of the present invention, in the configuration of the first aspect, the potential difference measuring electrode is a point electrode that is on an alignment line in all directions around the application electrode. Wherein said selective connection means sequentially selects a plurality of sets of adjacent point electrodes on an alignment line in a different direction with respect to one applied electrode and sequentially connects them to said potential difference measuring means.

According to the second aspect of the present invention, the potential difference and the polarity and magnitude of the potential difference are determined for one applied electrode by utilizing the characteristics of the change between the potential difference measuring electrodes adjacent in different directions.
It is possible to specify the leak position. For example, a current having the same phase as the applied voltage tends to flow toward the vicinity of the water leaking portion, and the measured value tends to change in an N-shape around the water leaking portion between two point electrodes adjacent in the measurement direction. Between two point electrodes adjacent to each other in a direction perpendicular to the line direction, there is a tendency that the respective lines along the line sandwiching the water leakage portion show peaks having different polarities. By utilizing the characteristic of the direction to be measured, the accuracy of specifying the water leakage position is improved.

Further, in the water leakage occurrence position detecting device according to the third aspect of the present invention, in the configuration according to the first or second aspect, the plurality of point electrodes or the surface is provided near a portion where the water shield works in contact with the ground. An annular electrode surrounding the periphery of the electrode is connected to the other end of the power supply.

According to the third aspect of the present invention, an annular electrode arranged so as to surround a plurality of point electrodes or surface electrodes is directly connected to the other end which is not the application side like the surface electrodes in the water shield structure. Thus, the electric field on the front and back of the water impervious structure, in which the annular electrode or the surface electrode covers the water impervious structure, is controlled to the same potential. The configuration in which the electric fields on the front and back of the seepage control are controlled to the same potential can reduce the influence of the current flowing through the protective layer, the ground, and the like.

Further, according to a fourth aspect of the present invention, there is provided a method for detecting a water leak occurrence position, wherein a water impervious structure is provided in which a water impervious work of an electrical insulator is laid in a depression formed in the ground. An electrode is provided, a plurality of point electrodes are provided on the opposite side of the plane electrode, one of the plurality of point electrodes is selected and connected to an application side of a power source to form an application electrode, and two adjacent electrodes are provided. Selecting the point electrodes as potential difference measurement electrodes, connecting all the point electrodes and the surface electrode except the selected applied electrode and potential difference measurement electrode to the other end of the power supply, A potential difference between the electrodes is measured, and a water leakage position of the seepage control structure is detected from the measured potential difference and the position of the application electrode.

According to the fourth aspect of the present invention, the fluctuation of the potential difference by the potential difference measuring electrode is measured only in the vicinity of the water leakage so that the potential inside and outside the water shielding structure becomes the same potential. Also, unlike the related art, the potential difference does not overlap due to the influence of water leakage, and the leaked portion can be reliably distinguished and detected. The two-phase AC power supply which is a component of the invention described above may be an alternating DC power supply.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a water leakage occurrence position detecting device according to an embodiment of the present invention will be described in detail with reference to FIGS. In addition, the water leak occurrence position detecting device according to the embodiment is installed in the water shielding structure 1. In addition, the case where the impermeable structure 1 is a managed waste final disposal site will be described.

As shown in FIG. 1, a water shield structure 1 has a water shield 2 laid in a depression 1a formed in the ground, and a protective layer 3 on a slope portion thereof so as to cover the entire water shield 2. It is a laminate. The water shield 2 is formed of a synthetic resin having electrical insulation. The protective layer 3 is formed of a concrete material that is not an electrical insulator, and the front side and the rear side of the water shield 2 laid on the water shield structure 1 are electrically short-circuited via the protective layer 3. The circuit can be formed.

The protective layer 3 used in the final disposal site for managed waste may be laid with a non-woven fabric (light-shielding mat) of polyester or polypropylene, or with a soil material or concrete. Compared with fibers, soil materials and concrete are more suitable for preventing ultraviolet light deterioration and heat deterioration of the water shielding work, and are known to be materials excellent in durability. In addition, concrete roads with extremely high durability are used as the material for roads carrying waste. Therefore, in this embodiment, description will be made assuming that the protective layer 3 made of concrete is laid.

In the water leakage occurrence position detecting apparatus according to the embodiment, a surface electrode 12 is arranged inside (a front surface side) of a water impervious structure 1 on which a water impervious work 2 is laid, and a rear surface side (a back surface side of the water impervious work 2) A plurality of point electrodes T _{a1 to} T _m14 (see FIG. 5) are arranged at predetermined intervals on the ground side) and an annular electrode 13 is arranged so as to surround the entire water shield 2.

The surface electrode 12 is made of a conductive metal foil, a metal net, or the like to have a planar shape. The surface electrode 12 is connected to one side 4 a of the AC power supply 4. In addition, since the leachate having high electric conductivity is discharged from the waste in the water shield structure 1 in the water shield structure 1, the linear electrode (for example, a bare copper wire) has a length of 10 m to 20 m.
They may be arranged in a grid at intervals.

On the other hand, there are _thirteen point electrodes T _{a1 to} T _m14 in the vertical direction in FIG.
82). These point electrodes T _{a1 to} T a
_An annular electrode 13 is arranged on the outer periphery of _m14 in the vicinity of a portion where the water shield 2 contacts the ground. This annular electrode 13
Is connected to one side 4a of the AC power supply 4 like the surface electrode 12. The plurality of point electrodes T _{a1 to} T _m14 are respectively connected to the potential difference measuring device 5 and one of the AC power supplies 4 4a or 4b via the electrode switching device 15.

The point when the electrode T _a1 is described in more detail a connection relationship through T _m14, electrode switching device 15 point electrodes T _a1 through T _m14
Of them (point electrode T _{g5 in} FIG. 5) and
_Is connected to the other side 4b, which is the application side, to form an application electrode _Tg5 (first selective connection means).

The electrode switching device 15 is connected to two adjacent point electrodes (in FIG. 6, the point electrode Tg5) on the _measurement line with respect to the applied electrode _Tg5 .
_g4 , T _g6 ) are selected and connected to the potential difference measuring device 5 to be used as potential difference measuring electrodes T _g4 , T _g6 (second selective connection means). When the second selection connection means selects an electrode for measuring a potential difference, the electrode switching device 15 determines that not only two adjacent electrodes on an alignment line that intersects the applied electrode T _{g5 at} right angles to the measurement line direction but also on the alignment line. 7 (point electrodes T _f5 , T
_h5 ) is also selected and connected to the potential difference measuring device 5 to form a potential difference measuring electrode. In other words, the second selective connection means sequentially selects a plurality of sets of adjacent point electrodes on an alignment line in different directions for one applied electrode, and sequentially connects to the potential difference measuring means.

Further, the electrode switching device 15 is provided with the selected mark.
An additional electrode (for example, T_g5) And potential difference measurement electrode (applying electrode
Is T_g5In the case of, the electrode for measuring the potential difference is T_g4, T_g6There
Is T _f5, T_h5), All point electrodes, surface electrodes 12 and rings
Electrode 13 is connected to one side 4a of AC power supply 4 (third electrode).
Selection connection means).

A power supply 4 (see FIG. 1) applies a voltage to a circuit formed by selective connection of an electrode switching device (first selective connection means) 15 between an applied electrode (for example, T _g5 ) and a plane electrode 12. Is applied. The power supply 4 may be alternate DC or AC, but in this embodiment, an AC power supply is used. When the power supply 4 is an AC power supply, the electrode switching device 1
The relationship between 5 and the potential difference measuring device 5 is as shown in the block diagram of FIG.

That is, the potential difference measuring device 5 uses the voltage applied between the applied electrode (eg, T _g5 ) and the plane electrode 12 to measure the potential difference between the potential difference measuring electrode (the potential difference measuring electrode when the applied electrode is T _g5 ). Is a device for measuring a potential difference between T _g4 and T _g6 or T _f5 and T _h5 ). As shown in FIG. 2, when the power supply 4 is an AC power supply, the potential difference measuring device 5 can be a differential circuit 5a that can easily obtain a potential difference. At this time, the same result can be obtained by separately measuring the potential difference between the potential difference measuring electrodes on both sides of the application electrode and a certain point and taking the difference between the measured potential values.

The voltage applied between the applied electrode (for example, T _g5 ) and the plane electrode 12 causes the second selective connection means to use the potential difference measuring electrode (if the applied electrode is T _g5 , the potential difference measuring electrode). When the electrodes are selected to be T _g4 , T _g6 ), the following circuit is formed. It is assumed that water leakage L ₁ , L ₂ , L ₃ has occurred in the water shield 2.

That is, (1) the electrode switching device 15 → the applied electrode T _g5 → the ground → the applied electrode T _g5 and the potential difference measuring electrode T _g4 ,
Point electrode and ring electrode 13 other than T _g6 → one 4a of AC power supply 4. (2) Electrode switching device 15 → applied electrode T _g5 → protective layer 3 → plane electrode 12 → one of 4a of AC power supply 4. (3) Electrode switching device 15 → applied electrode T _g5 → water leakage L ₁ , L ₂ ,
A circuit of L ₃ → surface electrode 12 → one 4 a of the AC power supply 4 is formed.

According to the circuits (1) to (3), the AC power supply 4 is connected between one applied electrode (for example, the applied electrode T _g5 ) selected by the electrode switching device 15 and the plane electrode 12. While a voltage is applied, one applied electrode (eg, applied electrode T _g5 ) and two potential difference measuring electrodes (eg, T _g4 ,
All the point electrodes except T _g6 ), the plane electrode 12 and the ring electrode 13 are controlled to the same potential by being connected to one side 4 a of the AC power supply 4 which is not the application side.

Therefore, the water leakage occurrence detecting device according to the present embodiment is constructed such that the circuits (1) to (3) are formed, so that the waterproof structure is formed by the protective layer 3 such as concrete or the ground. The electric fields on the front and back of the water shield 2 covering the object 1 are controlled so as to have the same potential except for one applied electrode and two potential difference measuring electrodes. When the thickness of the annular electrode 13 is compared with the cross-sectional area of the protective layer 3, it is difficult to control the current flowing through the protective layer 3 with only the 131 annular electrodes because the cross-sectional area of the protective layer 3 is large. , Annular electrode 1
It is preferable that 3 is more than one.

As described above, from the electrode arrangement of FIG.
The control of the potential on the front and back sides is performed by controlling the AC
One applied electrode (for example, an applied
Extreme T _g5) And two electrodes for measuring the potential difference (for example, T_g4, T
_g6Is done by connecting all point electrodes except)
You. Then, the potential difference measurement is performed on the ground side of the impermeable structure 1.
An electrode for measuring a potential difference (for example, T_g4, T_g6) Between
Done. Therefore, the fluctuation of the potential difference is measured only around the water leakage
Even if there are multiple leaks, the
Therefore, the potential difference does not overlap,
It can be detected separately.

In this embodiment, an applied electrode (for example, applied electrode T _g5 ) and an electrode for measuring potential difference (for example, T
_g4 , _Tg6 ) except for the point electrode which positively controls the potential on the front and back of the water shield 2 by using all the point electrodes, and it is advantageous that the point electrode has a wider area than a simple metal plate. Become.

[0036] Therefore, the point electrode T _a1 ~T _m14 (short T _XY
3), a bare copper wire is formed in a rectangular frame shape as shown in FIG. 3 and connected to another device via a cable connected to the point electrode _TXY . Incidentally, it may be formed bare copper wire helically in order to increase the sensitivity of the point electrode T _a1 through T _m14 electrode (electrode T _xy reference point in FIG. 4), it may be a rectangular metal plate.

Incidentally, an electrode for measuring a potential difference (for example, T
The potential difference between _g4 and _Tg6 ) is measured by the potential difference measuring device 5. As shown in FIG. 2, the potential difference measuring device 5 has a differential circuit 5a, an A / D converter 18, and a computer 19, and the differential circuit 5a is connected to the computer 19 via the A / D converter 18. .

The computer 19 comprises a ROM (Read Only Memory), RA interconnected by a bidirectional bus.
M (random access memory), CPU (central processing unit), input port, output port. The input port of the computer 19 is connected to the differential circuit 5a via the A / D converter 18, and receives an output signal (potential difference measurement value). The output port of the computer 19 is connected to the electrode switching device 15 (not shown) and outputs a command for switching the point electrode to the electrode switching device 15. The command for switching the point electrode is executed based on a selective connection procedure described later (first, second, and third selective connection means). Further, the output port of the computer 19 is connected to, for example, a CRT device (not shown), and outputs a display command (image data) to the CRT device.

The ROM stores a program for detecting a position where a water leak has occurred and a program for the first to third selective connection procedures. The CPU reads out these programs and performs processing. Note that the first selective connection procedure, the electrode switching device 15, from the left of the other 4b (application side) points connected to the electrodes T _a1 through T _m14 one by measuring line direction (Fig. 5 of the AC power source 4 to the right 182 in the direction of scanning from top to bottom)
This is a procedure for sequentially switching (horizontal direction × vertical direction; 14 × 13) types of selective connection procedures. Then, the CPU first (i =
1; for example, from the point electrode _Ta1 ) to the 182th (i
= 182; for example, the point electrode T _m14 ) is read from the ROM, and a command to switch the electrode switching device 15 is output. Then, an AC voltage is applied to an arbitrary point electrode for each command order, and the position of the point electrode is selected. Also, the second
In the electrode connection device 15, the electrode switching device 15 selects two point electrodes (potential difference measurement electrodes) adjacent to each other on the measurement line with respect to the applied electrode selected by the first selection connection means, and sends the selected electrode to the potential difference measurement device 5. This is the connection procedure. At this time, the third selective connection means connects all the point electrodes except the application electrode and the potential difference measurement electrode to one side 4a of the AC power supply 4. Further, in the second selective connection procedure, the electrode switching device 15 selects two point electrodes (potential difference measurement electrodes) adjacent to the application electrode selected by the first selective connection means in a direction perpendicular to the measurement line direction. And connected to the potential difference measuring device 5. Also at this time, the third selective connection means connects all the point electrodes except the application electrode and the potential difference measurement electrode to one side 4 a of the AC power supply 4. And C
The PU performs the second and third selective connection procedures in the first (i.
= 1) to 182th (i = 182) applied electrodes
A command is read from the OM to switch the electrode switching device 15.

Next, the leakage of the present invention by the computer 19 will be described.
The water generation position detection processing will be described based on the flowchart of FIG.
The computer 19 sets “i = 1” (step 10
1) According to the first selective connection procedure stored in the ROM
The electrode switching device 15 is switched to change the point electrode (and the position).
Select (step 102). That is, "i" is the first
(I = 1; point electrode T _a1), The electrode switching device 1
5 is a point electrode T_a1And the other 4b of the AC power supply 4
AC between one of the AC power supplies 4 connected to the electrode 12
A voltage is applied to select the positions of these point electrodes.

Next, the computer 19, in the second selective connection means in the "i = 1", with respect to application electrode T _a1 of the first selective connection means is selected, adjacent to the measuring line 2
The point electrodes (potential difference measuring electrodes) are selected and connected to the potential difference measuring device 5. In addition, when the point electrode _Ta1 is used as the application electrode (the point electrode at the corner in the arrangement diagram of FIG. 5; _Ta14 , _Tm1 ,
Since the two point electrodes adjacent to the application electrode do not exist at T _{m14 (the} same applies to T _m14 ) (that is, the corner point electrodes are used only for electric field control), the computer 19 proceeds to the processing at step 105. . The vertical direction of the point electrodes of the point electrodes of the outermost shown in FIG. 5; there are _{(T b1 ~T l1 T b14 ~T} l14) 2 pieces of point electrodes when the application electrode adjacent on measuring line a The computer 19 shifts to the process of step 104 because the point electrode in the outermost peripheral vertical direction has two point electrodes adjacent to each other in the direction perpendicular to the measurement line direction. However, when the point electrode T _g5 is used as the application electrode (“i =
As 89 "), application electrode T _g5 2 pieces of point electrodes neighboring on survey line to (6 point electrodes T _g4, T _g6) is selected if the point electrodes T _g4, T _g6 It is connected to the potential difference measuring device 5 to form a potential difference measuring electrode (second selective connection means). At this time, the third selective connection means connects all the point electrodes except the application electrode T _g5 and the potential difference measurement electrodes T _g4 and T _g6 to one of the AC power sources 4a.

Then, the potential difference measuring device 5 (differential circuit 5
In a), the potential difference between the potential difference measuring electrodes T _g4 and T _g6 is measured and output to the computer 19 via the A / D converter 18. Then, the computer 19 sets the potential difference value to “i”.
= 89 "in the RAM (step 103).

Next, the computer 19 sets "i = 89"
In the second selective connection means in (2), two point electrodes (point electrodes T _f5 and T _f5 in FIG. 7) adjacent to the applied electrode T _g5 selected by the first selective connection means in the direction perpendicular to the line-of-sight direction.
_Th5 ) is selected and connected to the potential difference measuring device 5. Also at this time, the third selective connection means connects all the point electrodes except the application electrode T _g5 and the potential difference measurement electrodes T _f5 and _{Th 5} to one side 4a of the AC power supply 4. Then, the potential difference measuring device 5 (differential circuit 5a) measures the potential difference between the potential difference measuring electrodes T _f5 and T _{h5 in the} same procedure as step 103, and the A / D converter 18
Output to the computer 19 via the
Stores the potential difference value in the RAM together with "i = 89" (step 104). The horizontal direction of the point electrodes of the point electrodes of the outermost shown in FIG. 5; the two points adjacent to the measuring line direction perpendicular to the direction in case of the _{(T a2 ~T a13 T m2 ~T} m13) the application electrode Since there is no electrode, the computer 19 proceeds to the process of step 105.

Next, the computer 19 determines whether the first selection switching procedure has been completed up to the 182nd (i = 182; point electrode T _m14 ) (step 105), and i = 18.
If 2 (Step 105: YES), Step 10
Step 7 and subsequent steps are performed. On the other hand, unless i = 182 (step 105: NO), the processing of step 106 is performed.

In step 106, the computer 1
9 increments the i-th by 1 (i = i +
1) Repeat the processing of step 102 and subsequent steps. That is, the computer 19 determines that “i = 1” to “i = 18”.
2) are stored.

In step 107, the computer 1
Reference numeral 9 outputs to the CRT device a command to display the potential difference value stored in the RAM on the CRT screen. Then, the CRT device sets “i = 1” to “i = 18” at the intersection of the CRT screen.
The measured values up to "2" are displayed (see FIG. 9 or FIG. 10).

When the measured value is displayed on the CRT screen, the computer 19 ends the water leak occurrence position detecting process.

[Detection of Water Leakage Occurrence Position Based on Potential Difference] Next, detection of a water leak occurrence position based on the measurement result shown in FIG. 9 or FIG. 10 which is a measurement example of the water leak occurrence position detecting device will be described. 9 and 10 show coordinates indicating a positional relationship corresponding to the arrangement diagram of the point electrodes in FIG.
And 1 to 14 are written in the horizontal direction. 9 and 10, the position of the point electrode _Ta1 is indicated by, for example, “a” in the vertical direction and “1” in the horizontal direction. In the case of proceeding from “1” of the “a” line to “14” of the “m” line, the measurement line direction proceeds from “1” to “14” from left to right on the “a” line in the figure, It is assumed that the line is changed to the line “b” one step below, and the line proceeds from left to right in the same manner. Further, in the coordinates of FIGS. 9 and 10, the potential difference is shown in accordance with each measurement line, and the upper side of each horizontal axis (measurement line) is positive and the lower side is negative.

FIG. 9 shows two adjacent electrodes on the measurement line for each applied electrode.
It is a coordinate diagram which displayed the potential difference measured between the point electrodes. In FIG. 9, when there is no water leak portion, the potential difference does not change. On the other hand, if there is a water leak in the water shield, the current in the same phase as the applied voltage tends to flow toward the area around the water leak. Distribution. Therefore, when the change of the potential difference is represented by a broken line graph as shown in FIG. 9, an N-shape is shown around the water leaking portions (L ₁ , L ₂ , L ₃ ). Then, from this potential difference distribution, the absolute value of the potential difference becomes larger as the position is closer to the water leaking portion, becomes 0 V at the water leaking position, and it can be seen that the water leaking portion is present around this.

Next, FIG. 10 is a coordinate diagram showing, for each applied electrode, a potential difference measured between two point electrodes adjacent to each other in a direction perpendicular to the measurement line direction. In FIG. 10, when there is no water leak portion, the potential difference does not change as in the case of FIG. on the other hand,
When there is a water leakage part in the water impervious works, the potential difference fluctuates, and when the fluctuation is represented by a broken line graph, peaks having different polarities are shown in the respective measurement lines sandwiching the water leakage part (L ₁ , L ₂ , L ₃ ). The potential difference shows the maximum value under the condition that the distance between the measurement line and the water leak is the shortest. FIG. 10 shows that the water leak portion has a positive maximum value under the condition on the right hand side of the survey line, and indicates that the water leak portion has a negative maximum value under the condition on the left hand side.

According to this embodiment, the potential difference and the polarity and magnitude of the potential difference are determined for one applied electrode by utilizing the characteristics of change between potential difference measuring electrodes adjacent in different directions.
It is possible to specify the leak position.

[0052]

According to the present invention, except for the vicinity of the application electrode and the potential difference measuring electrode, the front and back sides of the water shield work are controlled to the same potential, so that there is no water leak around the application electrode.
The potential gradient is theoretically measured to be 0 V, and a significant potential difference is measured under the condition that there is a water leak around the application electrode. Further, even if a plurality of leaks exist, the potential difference does not overlap due to the influence of the leak unlike the conventional case. Therefore, the fluctuation of the potential difference is measured only in the vicinity of the water leakage, and the water leakage part can be reliably distinguished and detected.

Further, according to the present invention, by controlling the front and rear surfaces of the water shield work to the same potential, a path for short-circuiting the front and back of the water shield work even if there is no water leakage, such as a waste carrying road at a waste disposal site. The part does not interfere with the measurement.

Therefore, the present invention can detect a water leak position reliably even if there are a plurality of water leak positions, and can improve the accuracy of detecting the water leak position, and a water leak occurrence position detecting device and its device. A method can be provided.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a seepage control structure.

FIG. 2 is a block circuit diagram of a part of the water leakage occurrence position detecting device according to the present invention.

FIG. 3 is an enlarged view of a point electrode.

FIG. 4 is an enlarged view of a point electrode.

FIG. 5 is a layout diagram of point electrodes.

FIG. 6 is an explanatory diagram in which a second selective connection means selects an electrode for measuring a potential difference, and shows a case where the electrode is adjacent to an application electrode on a measurement line.

FIG. 7 is an explanatory diagram in which a second selective connection means selects an electrode for measuring a potential difference, and shows a case where the electrode is adjacent to an application electrode in a direction perpendicular to the measurement direction.

FIG. 8 is a flowchart of a water leakage occurrence position detection process according to the present invention.

FIG. 9 is a coordinate diagram showing a measurement result of a potential difference, and shows a case where an electrode for measuring a potential difference adjacent to an application electrode on a measurement line is selected.

FIG. 10 is a coordinate diagram showing a measurement result of a potential difference;
The case where the potential difference measuring electrode adjacent to the application electrode is selected in a method perpendicular to the measurement direction is shown.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Water shielding structure 1a ... Depression 2 ... Water shielding work 3 ... Protective layer 4 ... AC power supply 5 ... Potential difference measuring device 5a ... Differential circuit 12 ... Surface electrode 13 ... Ring electrode 15 ... Electrode switching device 18 ... A / D converter 19 ... Computer

Claims (4)

[Claims] 1. A water impervious structure for laying a water impervious work of an electrical insulator in a depression formed in the ground, a surface electrode installed on either side of the water impervious work, and an opposite side of the surface electrode. A plurality of point electrodes installed at a plurality of point electrodes; a first selection connection means for selecting one of the plurality of point electrodes and connecting to an application side of a power source to form an application electrode; and a potential difference between the point electrodes excluding the application electrode. And a second selection connection means for selecting two point electrodes adjacent to the application electrode and connecting to the potential difference measurement means to form a potential difference measurement electrode, A water leakage occurrence position detecting device that detects a water leakage position of the impermeable structure from the measured potential difference and the position of the applied electrode, wherein all the point electrodes and the selected electrode except the selected applied electrode and the electrode for measuring a potential difference are used. A third selection for connecting a plane electrode to the other end of the power supply; A water leak occurrence position detecting device, comprising a selective connection means. 2. The potential difference measuring electrode is a point electrode on an alignment line in all directions around the application electrode, and the second selective connection means is on an alignment line in a different direction with respect to one of the application electrodes. The water leak occurrence position detecting device according to claim 1, wherein a plurality of sets of adjacent point electrodes are sequentially selected and connected to the potential difference measuring means. 3. An annular electrode disposed around the plurality of point electrodes or the surface electrode in the vicinity of a portion where the water shield works in contact with the ground, is connected to the other end of the power supply. Alternatively, the water leakage occurrence position detecting device according to claim 2. 4. A water impervious structure in which a water impervious structure of an electrical insulator is laid in a depression formed in the ground, and a surface electrode is installed on one of the front and rear sides of the water impervious structure. A plurality of point electrodes are provided, and one of the plurality of point electrodes is selected and connected to an application side of a power source to form an application electrode. Two of the point electrodes adjacent to the application electrode are selected to measure a potential difference All the point electrodes except the selected application electrode and the potential difference measuring electrode and the surface electrode were connected to the other end of the power supply, and the potential difference was measured between the potential difference measuring electrodes. A method for detecting a water leakage occurrence position, comprising detecting a water leakage position of the water shielding structure from a potential difference and a position of the application electrode.