JPH06101399A - Method and device for sensing water leakage - Google Patents

Abstract

PURPOSE:To provide a leak sensing device with an associate method therefore, which is applicable to objects over a wide sensing scope so that the whole structure can be covered. CONSTITUTION:A cord-form plastic composite material 12 which includes carbon fibers as electric conductive, is cut (13) on the way so that a gap C is generated. Changes in the electric traits (resistance value, voltage, current, etc.) of this composite 12 are measured. When water leak occurs and water intrudes into the cut part 13, the electric traits of the composite 12 vary to allow knowing that a leak bas happened. It may also be accepted that this sort of plastic composite 12 is used in combination with another 11 which has no cut 13. Therein the strain and stress condition in the object to be sensed can also be sensed from the changes in the electric traits of the composite 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water leak detecting method and a water leak detecting apparatus used therefor, and more particularly to a water leak detecting method using a plastic composite material containing conductive fiber bundles and a water leak detecting apparatus used therefor.

[0002]

2. Description of the Related Art Leakage of a structure such as a tunnel not only causes the user to feel uncomfortable by introducing water into the internal space of the structure, but also deteriorates the tunnel structure (lining body) itself. Including problems such as. For this reason, it is necessary to detect leak points such as tunnels as early as possible and to take measures to stop the leak points depending on the scale of the leak. In particular, in recent tunnels, after pouring concrete, it is often the case that a finishing material is further installed inside for the purpose of decoration, and it is particularly difficult to find water leakage. Naturally, a waterproof sheet is installed between the shotcrete and the rolled concrete to prevent water leakage to the rolled concrete side, but the installation of the waterproof sheet is incomplete or holes are made in the waterproof sheet. Then, water penetrates into the rolled concrete. As a result, the reinforcing bar of the rolled-up concrete is corroded and the reinforcing bar swells, destroying the concrete, or water is applied to the finishing material to cause deterioration of the finishing material.

[0003]

However, water leakage detection for large structures such as tunnels has not been systematized in the past, and it is the fact that visual inspection is regularly performed. . The present invention has been made in view of the above circumstances, and particularly provides a water leakage detection method and a water leakage detection device used therefor, which are effective when used for a large-scale target having a large detection range, such as a tunnel structure. The purpose is to do.

[0004]

The invention according to claim 1 is
A rod-shaped or string-shaped plastic composite material containing a conductive fiber bundle that is an assembly of conductive continuous fibers is attached to or embedded in an object of water leakage detection such as a structure, and the conductive material in the composite material. A water leakage detection method for detecting the presence or absence of water leakage from changes in electrical properties such as the resistance value of the fiber bundle, at least the conductive fiber bundle in the plastic composite material,
A state in which at least one position is cut in the lengthwise direction in the electrical characteristic measurement section and water is allowed to enter the cut portion, and the cut ends of the cut conductive fiber bundle are separated by a predetermined dimension. As a characteristic feature, the presence or absence of water leakage is detected by arranging at a site where water leakage is to be detected and measuring a change in the electrical characteristics of the electrically conductive fiber bundle at least in a section sandwiching the cut portion of the electrically conductive fiber bundle. It is what

The invention according to claim 2 is the method for detecting water leakage according to claim 1, characterized in that the continuous fibers having conductivity are carbon fibers. Further, the invention according to claim 3 is the method for detecting water leakage according to claim 1 or 2, wherein the distance between the cut ends of the conductive fiber bundle is set to 0.5 mm to 30.0 mm. Is.

A water leakage detection device according to a fourth aspect of the present invention is a rod-shaped or string-shaped plastic composite material containing a conductive fiber bundle which is an assembly of conductive continuous fibers, and the plastic composite material in a predetermined section. A measuring device for measuring a change in electrical characteristics such as a resistance value of a conductive fiber bundle, wherein the plastic composite material is provided in the section of the plastic composite material at predetermined intervals in a longitudinal direction of the plastic composite material. It is characterized in that at least one cut portion is cut.

The invention according to claim 5 is the water leakage detecting device according to claim 4, characterized in that the continuous fibers having conductivity are carbon fibers. Further, the invention according to claim 6 is the water leakage detection device according to claim 4 or 5, wherein the separation dimension of the cutting portion is 0.5 mm to 3 mm.
It is characterized by being 0.0 mm. further,
The invention according to claim 7 is the water leakage detection device according to any one of claims 4 to 6, wherein the plastic composite material is a reinforcing fiber bundle for reinforcing the composite material in addition to the conductive fiber bundle. It is characterized by containing.

The water leakage detection device according to claim 8 is a rod-shaped or string-shaped plastic composite material containing a conductive fiber bundle which is an assembly of conductive continuous fibers, and the plastic composite material in a predetermined section. A water leakage detection device comprising a measuring device for measuring a change in electrical characteristics such as a resistance value of a conductive fiber bundle, wherein the plastic composite material is vertically and horizontally assembled in a substantially lattice shape, and these vertically and horizontally assembled. Resistance value of the conductive fiber bundle in a predetermined section of the one plastic composite material with respect to at least one plastic composite material forming one of the columns or the horizontal rows of the plastic composite material. For the plastic composite material to which the first measuring device for measuring changes in isoelectric properties is connected and which constitutes the other row intersecting the one row, The at least one specific plastic composite material is in electrical contact with both of the intersecting conductive fiber bundles at at least two points of intersection with the plastic composite material forming the one row. The specific plastic composite material has a cutting portion, which is cut at a predetermined interval in the length direction of the specific plastic composite material, between the two intersections, and Then, a second measuring device for measuring a change in electrical characteristics such as a resistance value of the conductive fiber bundle in a predetermined section sandwiching the cut portion is connected.

According to a ninth aspect of the present invention, in the water leakage detection device according to the eighth aspect, the continuous fiber having conductivity is carbon fiber. Further, the invention according to claim 10 is the water leakage detection device according to claim 8 or 9, wherein the dimension of separation of the cutting portion is 0.5 mm to
It is characterized by being 30.0 mm. Also,
The invention according to claim 11 is the water leakage detection device according to any one of claims 8 to 10, wherein the plastic composite material includes, in addition to the conductive fiber bundle, a reinforcing fiber bundle for reinforcing the composite material. It is characterized by containing. Further, the invention according to claim 12 is the water leakage detection device according to any one of claims 8 to 11, wherein the plastic composite material is formed into a rod shape or a string shape like the composite material. Together with this, they are assembled in a substantially lattice pattern.

[0010]

A method for detecting water leakage according to claim 1 and claim 4
In the water leakage detection device described above, water intervenes in the cut portion of the conductive fiber bundle that is cut with a predetermined distance therebetween, whereby the electrical characteristics of the section of the conductive fiber bundle that sandwiches the cut portion changes. The presence or absence of water leakage can be known by reading this change in electrical characteristics.

In the water leakage detection device according to the eighth aspect, the water leakage can be detected by the plastic composite material having the disconnection portion and connected to the second measuring device, and at the same time, by the plastic composite material connected to the first measuring device measurement. The strain / stress state of the portion provided with the water leakage detection device can be detected.

In the water leakage detection method according to claim 2 or the water leakage detection device according to claims 5 and 9, by using relatively common carbon fiber as the conductive fiber, the water leakage detection method according to each of the above items or The versatility of the water leakage detection device can be improved.

The water leakage detecting method according to the third aspect or the water leakage detecting apparatus according to the sixth and tenth aspects realizes a water leakage detecting method or a water leakage detecting apparatus which is easy and stable to measure and detect water leakage.

In the water leakage detection device according to claims 7 and 11,
The strength of the plastic composite material is improved, and the structural strength of the water leakage detection device is increased.

In the water leakage detection device according to the twelfth aspect, the structural yield strength of the device is further enhanced, and the device can be used in a place where an external force is applied. Further, it is possible to make the water leakage detection device function as a reinforcing member for the structure.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of the configuration of the water leakage detection device according to the present invention. The water leakage detection device 1A is roughly configured by a sensor unit 40 having a substantially lattice shape and a measurement device 50 connected to the sensor unit 40. However,
The sensor section 40 shows a part thereof.

In this case, the sensor section 40 is
A solid rod-shaped or string-shaped main plastic composite material 10, 10, ... Shown by a thick solid line and an auxiliary plastic composite material 20 (also similarly shaped like a rod-shaped or string-shaped) shown by a solid line are assembled in a lattice shape. However, as shown in FIG. 1, the main plastic composite material 10 is the first main plastic composite material 1 which forms a row in the figure even in the case of the main composite material 10 alone.
1 and the second main plastic composite material 12 forming the column
And form a lattice.

The main plastic composite material 10 will be described below. As shown in FIG. 2, the main plastic composite material (hereinafter, abbreviated as “main composite material”) 10 includes a large number of continuous carbon fibers (continuous conductive fibers) 14
Carbon fiber bundle (conductive fiber bundle) 1 including a, 14a, ...
4 is integrally provided inside the plastic material 16.
In addition, the main composite material 10 in the present embodiment includes, inside the plastic material 16, in addition to the carbon fiber bundles 14,
The structure has a glass fiber bundle (reinforcing fiber bundle) 15. Further, in this case, the carbon fiber bundle 14 and the glass fiber bundle 15 are provided in a mixed state so that both continuous fibers are in close contact with each other.

On the other hand, the auxiliary plastic composite material (hereinafter abbreviated as "auxiliary composite material") 20 is not shown in the figure, but does not include the carbon fiber bundles 14 of the main composite material 10, that is, plastic. The material 16 has a structure containing a reinforcing glass fiber bundle 15 inside.

The first main plastic composite material constituted by the main composite material 10 having the above structure (hereinafter, referred to as "first
11 and a second main plastic composite material (hereinafter abbreviated as "second main composite material") 12
In forming the lattice as shown by the thick line in FIG.
At the intersections 17, 17, ... Of the two composite materials 11, 12, the plastic materials 16 forming the two composite materials 11, 12 are integrally joined, and at least the carbon of the two composite materials 11, 12 is the same. The fiber bundles 14 are in contact with each other (meaning electrical contact).

On the other hand, the auxiliary composite material 50 is
It is provided only in the direction parallel to the second main composite material 12, that is, only in the direction intersecting with the first main composite material 11. The intersections 18, 18, ... Between the auxiliary composite material 20 and the first main composite material 11 are formed by the plastic material 16 forming the auxiliary composite material 20 and the plastic material 16 forming the main composite material 11. Are united together. The glass fiber bundle contained in the auxiliary composite material 20 and the carbon fiber bundle 14 or the glass fiber bundle 15 contained in the main composite material 10 may or may not be in contact with each other. In order to facilitate understanding of the essence of the present invention, a description will be given here in advance.
The auxiliary composite material 20 merely reinforces the main composite material 10 assembled in a lattice shape, and does not participate in the water leak detecting action.

As shown in FIG. 1, the second main composite material 12 is cut in the longitudinal direction of itself between the intersections 17, 17 with the first main composite material 11, and the cut portion thereof is cut. A gap C having a predetermined size is formed at 13. FIG. 3 shows the cutting portion 13 of the second main composite material 12. This gap C
The size of is different depending on the strength of the action to be described later caused by the gap C, but normally it is desirable to set it in the range of 0.5 mm to 30.0 mm. Also, this second main composite material 12
In the cutting part 13 of the above, the cut carbon fiber bundle 1 is formed on both cutting end faces 12a, 12a facing each other through the gap C.
4 is exposed.

The above is the configuration of the sensor section 40.
Next, the measuring device 50 will be described. Measuring device 5
As shown in FIG. 1, 0 represents a power source 51 for applying a voltage to the main composite material 10 of the sensor unit 40, and a voltage applied from the power source 51 to the sensor unit 40 or its current or resistance value. Detecting galvanometer 52 (52A,
52B), and is mainly composed of an arithmetic recording device (not shown) that detects and records the change state of the measured value from the resistance value or current value, voltage value, etc. detected by the galvanometer. .

Electricity is supplied from the power source 51 to the carbon fiber bundles 14 of the main composite material 10. The embodiment shown in FIG. 1 will be described. In this case, the electric power supply line 54 from the power source 51 includes two first main composite materials 11A and 11A.
It is connected to one end 11a of one first main composite material 11A of B. The first galvanometer 52A is connected to the other end portion 11b of the one first main composite material 11A whose one end portion 11a is connected to the electric supply line 54. In the other first main composite material 11B, the second galvanometer 52B is connected to the other end 11b, and the electric supply line 54 is not connected to the one end 11a. Also, the first of both
The other end portions 11b and 11b of the main composite materials 11A and 11B reach the earth E after passing through the first galvanometer 52A and the second galvanometer 52B, respectively.

Next, the operation of the water leakage detection device 1A having the above-mentioned structure and the water leakage detection method according to the present invention will be described. The water leak detection device 1A according to the above embodiment has a water leak detection function and a strain / stress detection function.
First, the water leak detection function of these two functions will be described.

In the water leak detector 1A, the water leak is detected by the second galvanometer 52B. That is,
The current value of the second galvanometer 52B shows 0 (zero) in a state where no water is present around the water leakage detection device 1A.
This is because both the second main composite materials 12 and 12 are cut in the middle, so that the second galvanometer 52B is connected from the power source 51.
This is because the electric circuit up to (the electric circuit constituted by the carbon fiber bundles 14 of the main composite material 10) is interrupted midway.

On the other hand, it is assumed that water leakage occurs in a portion where the water leakage detection device 1A is present and the water leakage comes into contact with the water leakage detection device 1A. When water leakage exists between the gaps C of the cutting parts 13 of the second main composite materials 12, 12, the cutting parts 13 are conducted, and the measurement value of the second galvanometer 52B changes. That is, the current is measured.

Here, FIG. 4 shows an example of the result of the experiment conducted by the present inventors. This figure shows the change in the electrical characteristics of the electric circuit composed of the carbon fiber bundles 14 when the water leakage detecting device 1A as described above is used and water is applied to the cutting portion 13 from the state in which there is no water. It is a graph. However,
While the water leakage detection device 1A described above measures the current of the carbon fiber bundle 14, this experiment measures the voltage change under a constant current.

The present data was obtained with a constant current of 0.1 mA (at the time of conduction) and a size of the gap C of the cut portion 13 of 0.6 mm. In the figure, water was injected into the cutting portion 13 at point A, and water injection was stopped at point B. From this graph, it can be confirmed that a sudden voltage drop occurred in the electric circuit constituted by the carbon fiber bundles 14 of the main composite material 10 due to the water injection at the point a. This is because the circuit resistance decreased due to the presence of water in the cutting portion 13. Of course, even if the current change is measured as shown in FIG.
It can be read as an increase in current value (when the voltage is constant).

As described above, in the water leakage detection device 1A, the second galvanometer 52B is used to observe the change in the electric characteristics of the electric circuit constituted by the carbon fiber bundles 14 of the main composite material 10, thereby Intervention of water in the cutting unit 13, that is, water leakage can be detected.

From the graph of FIG. 4, it can be seen that the circuit voltage V is gradually increasing after stopping the water injection at the point B. This is because Joule heat is generated in the water having a larger specific resistance than the carbon fiber bundles 14 due to the flow of an electric current in the water interposed in the cutting portion 13, and the water itself generates heat in a relatively short time. It means that it has been removed (evaporated).

By the way, in the water leakage detection device 1A, two disconnection portions 13 are provided in parallel in the electric circuit from the power source 51 to the second galvanometer 52B. Therefore, when water leakage occurs, the measured value by the second galvanometer 52B changes if any one of the two cutting portions 13 and 13 is conducted, and the presence of water leakage is thereby detected. Can be detected.

On the other hand, contrary to the above, the measurement section by the second galvanometer 52B is changed from the power source 51 to the first main composite material 1 by way of example.
If it is up to the point between the second main composite materials 12, 12 in 1B, it is possible to detect water leakage only in one cutting portion 13 (the cutting portion 13 located on the left side in FIG. 1). . And, such switching of the measurement section is
If a tap line is drawn in advance in accordance with the section to be measured and the circuit constituted by the carbon fiber bundle 14 is appropriately tapped according to the section to be measured, the purpose is appropriately set even when there are a large number of cutting parts 13. It is possible to detect whether or not water leakage has occurred in the cutting portion 13 that is. In other words, this also makes it possible to detect the position of water leakage.

Further, the water leakage detection device 1A according to the above embodiment has a strain / stress detection function in addition to the above water leakage detection function. The strain / stress detection function will be described below. This relates to the invention that the present inventors pioneered before the present invention, in which the external force acts on the conductive fiber bundle such as the carbon fiber bundle 14 to distort the conductive fiber bundle. This is done by paying attention to the fact that, when it occurs, the electric resistance value of the conductive fiber bundle shows a peculiar change with respect to the strain amount or the change of the strain.

For example, FIG. 5 shows a conductive fiber bundle-containing plastic composite material having the same structure as the main composite material 10,
A load P when pulled in the length direction under predetermined conditions,
6 is a graph showing an example of the relationship between the strain amount ε of the conductive fiber bundle-containing plastic composite material and the increase resistance ΔR of the conductive fiber bundle. In the figure, ΔR represents an increasing resistance with respect to an initial resistance value (a resistance value in a state where no tensile load is applied). Further, in the diagram showing this ΔR, after the ΔR value exceeds the maximum value (point d in the figure) and reaches the point e in the figure, the strain amount ε of the conductive fiber bundle is a predetermined value. After becoming
The curve when the load P is unloaded is shown.

From FIG. 5, it can be seen that the electrical resistance value R of the conductive fiber bundle (carbon fiber bundle) gradually increases as the strain amount ε increases due to the increase of the tensile load P. And the load P
The electric resistance value R with the increase of R shows a tendency of three-stage transition such that it increases relatively sharply between points a and b, gradually between points b and c, and sharply from point c. Further, it can be seen that even if the load P is thereafter unloaded, the resistance value R does not return to the point a, that is, the initial resistance value, but shifts to a higher value. With respect to the above matters, the inventor of the present invention, even if various conditions are different, when the load is applied to a high strain region up to near fracture, the above tendency, that is, three-stage shift of the resistance value R and the high value of the resistance value R It has been confirmed by experiments that a tendency toward a shift occurs. The “condition” mentioned above includes the magnitude of the load P, the pulling speed, the type of conductive fiber, and the like. Further, the amount of shift of the resistance value R to the high value side after unloading, that is, the value between the points ae becomes substantially equal to the amount that has changed abruptly in the high strain region, that is, the value between the points cd. . Furthermore, when the load is applied to the first maximum strain value again after completely unloading the load P, the resistance value R (ΔR) rises by tracing the curve between the points e and d in a retrograde state almost as it is. , Unloading from there,
It was found that the same curve was drawn from point d to point e again. After that, the same is true even if this is repeated. Further, the position where the point c appears and the change in the resistance value (shift amount) between the points c and d differ depending on the strength and extensibility of the conductive fiber bundle. The strength shifts to the high strain region side, and the resistance value change amount between the cd points becomes larger when the conductive fiber bundle has high strength and high elongation.

As described above, the carbon fiber bundle 14 contained in the main composite material 10 exhibits a peculiar change in electrical characteristics such as resistance value with the strain generated in the carbon fiber bundle 14.
Therefore, it is possible to grasp the strain state of the structure by measuring the electric resistance value of the carbon fiber bundles 14 by attaching or embedding the main composite material 10 to the structure body, and thereby to know the stress level. You can Further, not only that, but the carbon fiber bundle 14 has the strain amount ε as described above.
Since the electric resistance value (electrical characteristic) with respect to the peculiar change shows, it becomes possible to use it as a kind of sensor for notifying the state of stress degree of a measurement object such as a structure. For example, the breaking strength of the carbon fiber bundle 14 is matched with the proof stress of the counterpart structure, and an alarm is issued when the electric resistance value R indicates the value of point c (mark point) in FIG. It is also possible to do so.
Further, when the carbon fiber bundle 14 is once subjected to a high strain near the breaking point, the electric resistance value R of the carbon fiber bundle 14 shifts to a high value, so that the other structure causes a high strain. Whether or not it is a thing, or even its degree can be known by the amount of shift, and the stress history of the structure can be grasped. Therefore, for example, it is possible to know the current stress level occurring in a structure, the maximum stress level caused by an external force such as an earthquake, and the stress level history, which can be used for proof stress monitoring and failure prediction of the structure. it can.

Regarding the strain / stress function of the plastic composite material containing the conductive fiber bundles, more specifically, Japanese Patent Application No. 3-205303 “strain / stress detector and Refer to "Structure Strain / Stress Detecting Method Using the Same" and Japanese Patent Application No. 4-62668 "Fiber Bundle-Containing Plastic Composite Having Fracture Prediction Mechanism and Structure Predicting Method Using It". I want to.

FIGS. 6 and 7 show a second embodiment of the present invention, in which a leak detecting device 1B having substantially the same structure as the leak detecting device 1A is used for detecting leaks in a tunnel structure. It is shown. The water leakage detection device 1B is a large-sized device for applying the water leakage detection device 1A to a tunnel structure, that is, the number of each main composite material 10 and the number of auxiliary composite materials 20 are large and each length is large. Further, it is formed in a tubular shape as a whole so as to match the tunnel structure forming the curved surface. FIG. 7 shows this water leakage detection device 1
B is plural in the length direction of the tunnel (4 in the example shown)
It shows a state in which they are arranged in series. In this water leak detection device 1B, the same components as those of the water leak detection device 1A are designated by the same reference numerals, and description of common items is omitted.

In FIG. 6, reference numeral G is a rock mass, reference numeral 70 is a shotcrete applied to the excavated wall surface of the rock mass G, 7
2 is roll-up concrete that is applied to the inner surface of sprayed concrete 70 via a waterproof sheet 71, 73 is rebar embedded in this roll-up concrete 72, and 74 is finish provided on the inner surface of roll-up concrete 72. It is a material. These sprayed concrete 70, waterproof sheet 7
1, rolled concrete 72, rebar 73, finishing material 74
The tunnel structure 75 is configured by. In this case, the water leakage detection device 1B is provided inside the rolled-up concrete 72 and inside the rebar 73 (on the side opposite to the ground surface).

Now, a plurality of water leakage detection devices 1B,
One of the water leak detection devices 1B of 1B, ... Will be described. This water leak detection device 1B is basically the same as the water leak detection device 1A shown in FIG.
It may be considered that the shape is a shape in which the winding direction is B and the winding direction is approximately one round. That is, in the water leakage detection device 1B, as shown in FIG. 7, the first main composite materials 11A and 11B are curved along the tunnel cross-sectional shape and are arranged at predetermined intervals in the tunnel longitudinal direction. Then, these first main composite materials 1
The second main composite material 12, 12, ..., Over 1A and 11B
And the auxiliary composite materials 20, 20, ... Are provided in a erected state. As shown in FIG. 7, each auxiliary composite material 20, 20,
Is a continuous 1 between the first main composite materials 11A and 11B
In contrast to this, each second main composite material 12 has a cutting portion 13 between the first main composite materials 11A and 11B. In this case, the cut portions 13, 1 in the second main composite material 12
The size of the gap of 3, ... is about 2 cm. In addition, the intersection points 17 of the respective first main composite materials 11 and the respective second main composite materials 12,
In the case of Nos. 17, ..., the carbon fiber bundles forming the both composite materials 11 and 12 are in a state of being in electrical contact with each other.

At one end of the first main composite material 11A, the first
A power supply 51 for applying a voltage is connected to the main composite material 11A. In addition, at the other end of the first main composite material 11A, a first member for measuring the electrical characteristics (for example, the current value when a constant voltage is applied) of the carbon fiber bundle that constitutes the first main composite material 11A is provided. A galvanometer 52A galvanometer is provided. On the other hand, the second galvanometer 52B is connected to one end of the other first main composite material 11B forming a pair. In the illustrated example, in order to avoid complexity of the drawing, the configuration having the measuring device 50 for only one water leakage detection device 1B is shown, but in actuality, the other water leakage detection devices 1B, 1B, ... A measuring device 50 is provided.

The operation of the water leakage detection device 1B having the above structure is as follows. For example, it is assumed that water leakage occurs in the tunnel structure 75 as indicated by the symbol W in FIG. This water leak W
However, for example, it is assumed that any of the cutting parts 13, 13, ... Has just been reached. Before the water leakage W occurs, no current flows between the first main composite materials 11A and 11B. This is because the electric circuit (the electric circuit formed by the carbon fiber bundle) between the first main composite materials 11A and 11B is cut by each cutting portion 13. On the other hand, when the water leakage W reaches any one of the cut portions 13 as described above, the cut portion 13 is conducted by the water leakage W, and the other first main composite material 11B.
Current also flows. This current is detected by the second galvanometer 52B and the arithmetic recording device connected thereto,
It is detected that water has leaked between the first main composite materials 11A and 11B. Other water leakage detection devices 1B, 1B,
Similarly, the water leak W is detected.

On the other hand, each of the water leak detectors 1B, 1B, ...
The first main composite materials 11A, 11A, ... And the first galvanometers 52A respectively connected to the first main composite materials 11A, 11A, ... Are based on the principle described in the previous embodiment. Detect the stress level of the buried part.

Further, the sensor section 40 of the water leakage detection device 1B
Are provided with auxiliary composite materials 20, 20, ... In addition to the main composite material 10, the sensor portion 40 is structurally reinforced by these auxiliary composite materials 20, and the sensor portion 40 is provided with the sensor structure 40, for example, as in the tunnel structure 75. It can also be provided at a portion where an external force is applied to the portion 40. Further, since the outer surfaces of both the main composite material 10 (11, 12) and the auxiliary composite material 20 that form the sensor unit 40 are formed of the plastic material 16, the interior of the structure or the ground is buried in this way. However, there is almost no risk of the sensor section 40 corroding, and a stable function can be maintained for many years.

Moreover, the sensor section 40 is composed mainly of the plastic material 16 and contains the carbon fiber bundles 14 and the glass fiber bundles 15 therein, and the main composite material 10 and
The auxiliary composite material 20 containing a glass fiber bundle is integrally assembled in a lattice shape. Therefore, the sensor unit 40 itself has a large proof stress particularly against its out-of-plane displacement. Therefore, when the sensor section 40 is embedded in a wide range inside the structure as in the above embodiment, it is possible to expect the sensor section 40 itself to reinforce the structure. In addition, the sensor portion 40 having such a configuration is excellent in corrosion resistance and is lightweight, and construction is easy even when it is provided over a wide range as described above.

Further, if the water leakage W that has intervened in the cutting portion 13 is temporary, it will disappear in a relatively short time due to Joule heat as described above, and in that case, the second galvanometer 52B. The measured value by will gradually return to the state where no water leakage occurs. In other words, this means that it is possible to distinguish between temporary water leakage that is not a concern and steady water leakage that is alarming.

Next, FIG. 8 shows a third embodiment of the present invention. Water leakage detection device 1C, 1 according to the third embodiment
C, ... Are developed types of the water leakage detection device 1B according to the second embodiment. In the present embodiment, the same components as those shown in the first and second embodiments above are designated by the same reference numerals and the description thereof will be omitted.

The water leakage detection device 1C according to the third embodiment is
In the sensor unit 40 of the water leakage detection device 1B, the second
A non-woven fabric 19 having high water absorption is provided on the outer periphery of the main composite materials 12, 12 ,. This non-woven fabric 1
9 has a function of guiding the leaked water to the cutting portion 13 when the water leakage occurs at a location apart from the cutting portion 13 in the second main composite material 12. Therefore, as shown in FIG. 8, the non-woven fabric 19 is continuous even in the cutting portion 13.

The non-woven fabric 19 makes it possible to detect water leaks occurring in places other than the cutting portion 13 and realize a wider range of water leak monitoring. Moreover, in the above configuration,
Since the cut portion 13 of the second main composite material 12 is covered with the non-woven fabric 19, even when the sensor portion 40 is embedded in concrete as in the present embodiment, the gap C of the cut portion 13 at the time of pouring concrete is obtained. It is preferable since it is possible to prevent mixing of concrete into the concrete. Further, by covering the cut portion 13 with the non-woven fabric 19 in this manner, when there is a possibility that a short circuit in the cut portion 13 due to water leakage W may become uncertain, a conductive agent is applied to a portion of the non-woven fabric 19 corresponding to the cut portion 13. It is preferable to include it.

In each of the above embodiments, the dimension of the gap C of the cut portion 13 of the second main composite material 12 is preferably set to 0.
The size of this gap C is set to 0.5 mm to 30.0 mm.
If the distance is less than 5 mm, there is a possibility that the cut end surfaces 12a and 12a (Fig. 3) may contact each other carelessly and the gap C may disappear because the sensor portion 40 has flexibility.
This is because if m is exceeded, even if the water leakage W intervenes in the gap 13, there is a possibility that the resistance will be large and the comparison with the normal state will not be made clear.

Also, the cut end 12 of the second main composite material 12
In a and 12a (FIG. 3), not only is the carbon fiber bundle 14 exposed at the end, but also for better conduction,
You may provide a terminal.

Next, each of FIGS. 9 to 11 shows another embodiment of the water leakage detection device according to the present invention. In these embodiments, in particular, the sensor unit 40
The connection form of the measuring device 50 with respect to the first main composite material 11 and the second main composite material 12 constituting the above is changed, whereby the strain / stress detection by the first main composite material 11 and the second main composite material are changed. This is a change in both measurement forms of water leakage detection by 12.

First, the water leak detection device 1D shown in FIG. 9 has a structure in which two water leak detection devices 1A shown in FIG. That is, in this water leakage detection device 1D, the first main composite material 11A, 11A
The first galvanometers 52A and 52A connected to detect the strain and stress, and the second galvanometers 52B and 52B connected to the first main composite materials 11B and 11B detect water leakage.

The water leakage detection device 1E shown in FIG. 10 is similar to the water leakage detection device 1D described above in that it has an electric supply line 54 from a power source 51.
However, one end portion 1 of each of the first main composite materials 11A and 11A
It is connected to 1a and 11a. On the other hand, the other end portions 11b of the two first main composite materials 11A and 11A,
11b is selectively connected to the first galvanometer 52A via the circuit changeover switch 55. In addition, the first main composite material 11
A second galvanometer 52 is provided at one end 11a of each of B and 11B.
B and 52B are respectively connected. In addition, the connection configuration and the like of the second main composite material 12 are the water leakage detection device 1 shown in FIG.
Same as D.

In the water leakage detecting device 1E having the above-mentioned structure, when the water leakage reaches the sensor portion 40 (strictly speaking, the cutting portion 13), the water leakage is always detected by the second galvanometer 52B. On the other hand, regarding the detection of strain / stress, the circuit changeover switch 55 is switched to the I or II position to detect the strain / stress due to one of the first main composite materials 11A, or to detect the other first main component. It is possible to select whether to detect the strain / stress due to the composite material 11A. It is also possible to use the circuit changeover switch 55 normally set to the neutral position (OFF) as shown in the figure, and the strain / stress detection is performed only when necessary. Further, in the case of the water leakage detector 1E, the first galvanometer for detecting the strain / stress regardless of the number of installation locations of the first main composite material 11 for detecting the strain / stress. It is possible to use only one 52A.

The water leakage detection device 1F shown in FIG. 11 is similar to the water leakage detection device 1E except that the second galvanometers 52B and 52 are used.
B is omitted, and the water leakage detection by the first main composite materials 11B and 11B is also performed by the first galvanometer 5 through the circuit changeover switch 55 '.
It is wired so that it can be performed by 2A. That is,
In this case, the first galvanometer 52A also serves as a second galvanometer for detecting water leakage.

In the water leakage detection device 1F having the above structure, both the water leakage detection and the strain / stress detection are performed by the first galvanometer 52A. To detect water leakage, use the circuit changeover switch 55 '.
By switching to the position of III or IV, which of the first main composite materials 11B is to be detected is selected. The strain / stress can be detected by switching the circuit selector switch 55 'to the I or II position.
Whether to detect by the main composite material 11A is selected. Therefore, the water leakage detection device 1F performs regular measurement instead of so-called constant measurement for both water leakage detection and strain / stress detection.

As described above, in the water leakage detection device shown in each of the above embodiments, the combination of the sensor unit 40 and the measuring device 50 is arbitrarily set, and the main composite material 1 constituting the sensor unit 40 is configured.
It is possible to easily arrange the selection and measurement form such as which position of 0 to detect the water leakage or the strain / stress state according to the request of the measurement side. In addition, in each of the water leakage detection devices 1D to 1F, a configuration is shown in which two pairs of the sensor units 40 each including the pair of first main composite materials 11A and 11B are provided, but this will not be described. It is needless to say that a large number of these sensor units 40 may be arranged in series as shown in FIG. 7 for the sake of simplification.

Further, in the above-described embodiment, as an example of providing the water leakage detection device according to the present invention in a structure or the like, an example in which the water leakage detection devices 1B and 1C are installed in the tunnel structure 75 has been shown.
However, the water leakage detection device according to the present invention can be applied to other places requiring water leakage detection, such as water and sewer pipes, floors of chemical warehouses, floors and wall surfaces of computer rooms, museums, etc. it can.

Further, in each of the above-mentioned embodiments, only the example using the carbon fiber bundle is shown as the conductive fiber bundle according to the present invention.
As is clear from the operation of the present invention, the conductive fiber bundle according to the present invention may be a good conductor of electricity, and the carbon fiber bundle 1
Conductive fiber bundles other than 4 may be used. Similarly, the reinforcing fiber provided in the main composite material 10 together with the conductive fiber bundle and the reinforcing fiber incorporated in the auxiliary composite material 20 are not limited to the glass fiber.

Further, in the embodiment, in the sensor section 40 constructed by assembling the plastic composite material in a matrix form in the vertical and horizontal directions, the composite material forming one row of the horizontal row or the vertical row is made to function for water leakage detection, and the other row is made to function. Although the composite material constituting the above-mentioned is made to function for strain / stress detection, the composite material functioning for water leakage detection or strain / stress detection may be present in both vertical and horizontal rows.

[0063]

As described above, according to the water leakage detection method of the first aspect, it is possible to reliably detect water leakage with an extremely simple structure. In addition, since a plastic composite material that is lightweight, has excellent corrosion resistance, and is easy to handle is used as the sensor unit that substantially detects water leakage, it can be installed anywhere, especially when it is embedded in the ground or inside the structure. Can be used. Moreover, by providing a large number of cut portions of the conductive fiber bundle and measuring the electrical characteristics of the conductive fiber bundle between the cut portions, it is possible to detect the location of water leakage.

According to the water leakage detection method of the second aspect, the general versatility of the water leakage detection method of the first aspect is enhanced by using the carbon fiber that is generally used as the plastic-containing fiber as the conductive fiber. You can

According to the water leakage detection method of the third aspect, it is easy to measure and judge whether or not water (leakage) exists at the cut portion of the conductive fiber bundle, and eliminate the gap of the cut portion ( Accidents such as (contact) are reliably prevented and stable measurement is realized.

According to the water leakage detection device of the fourth aspect, the water leakage detection method of the first aspect can be realized to reliably detect the water leakage. In addition, the plastic composite material, which functions as a sensor for detecting water leakage, is lightweight, has excellent corrosion resistance, and is easy to handle, so it can be attached or buried in any location, and stable operation can be expected over a long period of time. . Moreover, since the length and the like of the plastic composite material can be freely set, it is easy to apply it to a particularly long object. Further, by providing a large number of cut portions of the conductive fiber bundle and measuring the electrical characteristics of the conductive fiber bundle between the cut portions, it is possible to detect the location of water leakage.

According to the water leakage detection device of the fifth aspect, the water leakage detection device of high versatility according to the fourth aspect can be provided by using the carbon fiber generally used as the plastic-embedding fiber as the conductive fiber bundle. To be realized.

According to the water leakage detection device of the sixth aspect, it is possible to facilitate the measurement and determination of the presence or absence of water (leakage) at the cutting portion of the conductive fiber bundle in the device, and the cutting portion. Accidents such as gap disappearance (contact) are reliably prevented, and stable measurement is realized.

According to the water leakage detection device of the seventh aspect, the strength of the plastic composite material itself can be increased, and the structural resistance of the sensor portion actually provided at the water leakage detection position in the device can be increased.

According to the water leakage detection device of the eighth aspect, the water leakage can be detected by the change in the electrical characteristics of the plastic composite material (conductive fiber bundle) having the disconnection portion and connected to the second measurement device, and the first water leakage detection device can be used. The strain / stress state of the portion where the water leak detection device is provided can be detected from the change in the electrical characteristics of the plastic composite material (conductive fiber bundle) to which the measurement device is connected. That is, it is possible to monitor both the water leak and the strain / stress state of the object by using one device composed of the plastic composite material.

According to the water leakage detection device of the ninth aspect, the highly versatile water leakage detection device according to the eighth aspect can be obtained by using the general carbon fiber as the plastic-embedded fiber as the conductive fiber bundle. To be realized.

According to the water leakage detection device of the tenth aspect,
In the cut part of the conductive fiber bundle, it is easy to measure and judge the presence or absence of water (leakage), and the accident such as disappearance (contact) of the cut part gap is surely prevented, and stable measurement is possible. To be realized.

According to the water leakage detection device of the eleventh aspect,
The strength of the plastic composite material itself is increased, and the structural resistance of the sensor portion actually provided at the water leakage detection location in the device can be increased.

According to the water leakage detection device of the twelfth aspect,
The structural proof strength of the sensor portion actually provided at the water leakage detection location in the device can be increased, and the device can be suitably used in a place to which an external force is applied. When the water leakage detection device is embedded inside the structure, it is possible to function as a reinforcing member for the structure in combination with the fact that the plastic composite material is formed in a lattice shape. It has excellent effects such as.

[Brief description of drawings]

FIG. 1 is a partial plan view showing a basic form of a water leakage detection device according to an embodiment of the present invention.

FIG. 2 is a partial perspective view showing a structural example of a plastic composite material according to the present invention.

FIG. 3 is a perspective view showing a cut portion of the plastic composite material according to the present invention.

FIG. 4 is a view for explaining the action of the water leak detection method and the water leak detection device according to the present invention, showing one state of change in the electrical characteristics of the conductive fiber bundle when the water leak intervenes in the cut portion of the conductive fiber bundle. It is a graph which shows an example of an experiment.

FIG. 5 is a view for explaining the action of the water leakage detection device according to one embodiment of the present invention, showing the load, strain amount, and increased resistance when a tensile load is applied to the conductive fiber bundle contained in the plastic composite material. It is a graph showing a relationship.

FIG. 6 is a partial front cross-sectional view showing a state in which the water leakage detection device according to the embodiment of the present invention is embedded inside a tunnel structure.

FIG. 7 is a partial perspective view showing an arrangement configuration example of a plastic composite material when the water leakage detection device according to the embodiment of the present invention is used in a tunnel structure.

FIG. 8 is a partial perspective view showing an arrangement configuration example of a plastic composite material when the water leakage detection device according to the embodiment of the present invention is used in a tunnel structure.

FIG. 9 is a partial plan view showing another configuration example of the water leakage detection device according to the present invention.

FIG. 10 is a partial plan view showing another configuration example of the water leakage detection device according to the present invention.

FIG. 11 is a partial plan view showing still another configuration example of the water leakage detection device according to the present invention.

[Explanation of symbols]

1A to 1F Water leakage detection device 10 Main plastic composite material (plastic composite material) 11 (11A, 11B) First main plastic composite material (〃) 12 Second main plastic composite material (〃) 13 Cut portion 14 Carbon fiber bundle (Conductive Fiber Bundle) 14a Carbon Fiber (Conductive Fiber) 15 Glass Fiber Bundle (Reinforced Fiber Bundle) 17 Intersection (Intersection) 20 Auxiliary Plastic Composite Material (Fiber Reinforced Plastic Material) 52 Galvanometer (Measuring Device) 52A No. 1 Galvanometer (1st measuring device) 52B 2nd Galvanometer (2nd measuring device) C Gap W Water leakage

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Minoru Sugita 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Teruyuki Nakatsuji 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Incorporated (72) Inventor Yasushi Otsuka 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Construction Co., Ltd. (72) Inventor Norio Muto 1-6-6 Moto-Akasaka, Minato-ku, Tokyo Sogo Guard Security Co., Ltd. In-house (72) Inventor Sadao Hasegawa 1-6-6 Moto-Akasaka, Minato-ku, Tokyo Sogo Security Guarantee Co., Ltd. (72) Inventor Koji Takada 1-6-6 Moto-Akasaka, Minato-ku, Tokyo Sogo Guard Insurance Co., Ltd.

Claims (12)

[Claims] 1. A rod-shaped or string-shaped plastic composite material containing a conductive fiber bundle, which is an assembly of conductive continuous fibers, is attached to or embedded in a water leakage detection target such as a structure, and the composite material. A water leakage detection method for detecting the presence or absence of water leakage from a change in electrical characteristics such as the resistance value of the conductive fiber bundle, wherein at least the conductive fiber bundle in the plastic composite material is long in the electrical characteristic measurement section. It is configured to cut at least one place in the depth direction and to allow water to enter the cut portion, and to cut water at a portion where the cut ends of the cut conductive fiber bundles are separated from each other by a predetermined dimension. It is arranged to detect the presence or absence of water leakage by measuring a change in the electrical characteristics of the conductive fiber bundle at least in a section sandwiching the cut portion of the conductive fiber bundle. Water leak detection method according to symptoms. 2. The water leakage detection method according to claim 1, wherein the conductive continuous fibers are carbon fibers. 3. The water leakage detection method according to claim 1, wherein the distance between the cut ends of the conductive fiber bundle is set to 0.5 mm to 30.0 mm. 4. A rod-shaped or string-shaped plastic composite material containing a conductive fiber bundle, which is an aggregate of conductive continuous fibers, and a resistance value of the conductive fiber bundle in a predetermined section of the plastic composite material. A measuring device for measuring a change in electrical characteristics, wherein the plastic composite material is cut in the section of the plastic composite material at predetermined intervals in the length direction of the plastic composite material. The water leakage detection device is characterized in that at least one is formed. 5. The water leakage detection device according to claim 4, wherein the conductive continuous fiber is a carbon fiber. 6. The separation dimension of the cut portion is 0.5 mm to 3 mm.
The water leakage detection device according to claim 4 or 5, wherein the water leakage detection device has a thickness of 0.0 mm. 7. The plastic composite material, in addition to the conductive fiber bundle, contains a reinforcing fiber bundle for reinforcing the composite material. The leak detection device described. 8. A rod-shaped or string-shaped plastic composite material containing a conductive fiber bundle, which is an assembly of conductive continuous fibers, and a resistance value of the conductive fiber bundle in a predetermined section of the plastic composite material. A water leakage detection device comprising a measuring device for measuring changes in electrical characteristics, wherein the plastic composite material is vertically and horizontally assembled in a substantially lattice pattern, and among these plastic composite materials vertically and horizontally assembled, a column Alternatively, with respect to at least one plastic composite material forming one row of the horizontal rows, a change in electrical characteristics such as a resistance value of the conductive fiber bundle in a predetermined section of the one plastic composite material is measured. A first measuring device is connected to the plastic composite material forming the other row intersecting the one row, and at least one specific At least at two points of intersection of the plastic composite material with the plastic composite material forming the one row, both conductive fiber bundles intersecting each other are brought into electrical contact with each other, and the specific plastic composite material is , A cutting portion cut at a predetermined interval in the length direction of the specific plastic composite material between the intersections of the two locations, and the cutting portion is formed on the specific plastic composite material. A water leakage detection device, to which a second measuring device for measuring a change in electrical characteristics such as a resistance value of the conductive fiber bundle in a sandwiched predetermined section is connected. 9. The water leakage detection device according to claim 8, wherein the conductive continuous fibers are carbon fibers. 10. The separation dimension of the cutting portion is 0.5 mm.
The water leakage detection device according to claim 8 or 9, wherein the water leakage detection device is 30.0 mm. 11. The plastic composite material contains, in addition to the conductive fiber bundle, a reinforcing fiber bundle for reinforcing the composite material. The leak detection device described. 12. The plastic composite material is assembled in a substantially lattice shape together with a fiber-reinforced plastic material formed in a rod shape or a string shape like the composite material.
1. The water leakage detection device according to any one of 1.