JP2001153603A - Maximum value storing type sensor for detecting amount of deformation and method for measuring amount of deformation of structure by using the sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive the maximum deformation detecting sensor with a simple structure and easy to handle that surely enables to detect the maximum deformation, and a method for detecting the maximum deformation. SOLUTION: This sensor 1 comprises a base 2 made of a material having a low yield and a resistor 3 obtained by dispersing conductive particles in a polymer being arranged on the base 2 in an electrically insulating state. Moreover, a method for detecting the maximum deformation of a structure by using the sensor 1 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a maximum value storage type deformation amount detection sensor and a method for measuring a maximum deformation amount of a structure using the sensor, and more particularly to a maximum load applied to a member to be inspected in the past. The present invention relates to a deformation amount detection sensor for detecting a maximum deformation amount and a displacement amount, and a method for measuring a maximum deformation amount of a structure using the sensor.

[0002]

2. Description of the Related Art Due to earthquakes and typhoons, buildings, bridges, ships on the sea, and aircraft in the sky receive large external forces temporarily or over time, and these structures undergo a change in strength. It is necessary to detect this intensity change non-destructively and make a predictive diagnosis of the possibility of the structure being destroyed.

For this nondestructive predictive diagnosis, various maximum deformation amount detection sensors are fixed to a structure in advance,
At the time of inspection, there is a method of obtaining the maximum deformation amount from the resistance value of the maximum deformation amount detection sensor and the optical transmission loss amount.

For example, Japanese Unexamined Patent Publication No. 6-331581 discloses a maximum deformation amount detection sensor for detecting a maximum deformation amount by detecting a change amount of a resistance value. A maximum deformation amount detection sensor that quantitatively detects the degree of past load by irreversible changes in electrical resistance caused by destruction of the sensor element due to external force, and a structure using this A method for measuring the maximum deformation of an object is disclosed. As a problem of the maximum deformation amount detection sensor and the method of measuring the maximum deformation amount of a structure using the same, a different slack is given to the sensor element, and the difference in the degree of the slack is used to respond to the deformation amount in the detected member. Since the maximum amount of deformation is detected by causing sequential self-rupture, setting the degree of deflection of each conductive element is an important factor in stabilizing the detection accuracy, and the tension of each sensor element Although the detection accuracy is easily affected by the variation in strength, it is difficult to set a slightly different degree of deflection for each sensor element, so that the sequential breakage of each sensor element according to the amount of deformation of the detected member is ensured. In some cases, it is difficult to maintain the uniformity of the tensile strength of each sensor element, and it is difficult to sufficiently maintain the stability of the detection accuracy.

Japanese Patent Laid-Open Publication No. Hei 8-178765 discloses that a plurality of sensor elements (conductive elements) are arranged in parallel.
Further, a folded portion is formed in the middle of the sensor element, and cutting means formed so as to have a slope with respect to the folded portion is provided opposite to the folded portion, and relative movement of the sensor element and the cutting means is provided. A maximum deformation amount detection sensor for quantitatively detecting the degree of a past load in which a sensor element is sequentially cut in accordance with the amount of movement of the sensor is disclosed. As a problem of the maximum deformation amount detection sensor, since the sensor element is sequentially cut using the cutting means, there is a problem of the reliability and detection accuracy of the cutting, and the performance due to deterioration of the cutting means with time. It lacks stability and has a complicated structure and has a problem in productivity.

Further, Japanese Patent Application Laid-Open No. 9-14927 discloses an optical fiber strain sensor provided with a spiral optical fiber in close contact with the inner peripheral surface of a metal tube. An optical fiber strain sensor for detection and a method for measuring strain of a structure using the same are disclosed. The problem with this optical fiber strain sensor and the method of measuring the strain of a structure using it is that it is more expensive than a sensor that measures electrical resistance to detect strain, and that it is necessary to measure the amount of optical transmission loss. Measuring devices such as a light source and a power meter used are more expensive than devices for measuring electric resistance, and also have problems such as being large-scale.

Therefore, there is a demand for a sensor for detecting the maximum deformation amount of a structure which has high detection accuracy, is highly reliable, has a simple structure, is easy to handle, is inexpensive, and uses the same. ing.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a simple structure, easy handling, low cost, and a maximum deformation amount of a structure that can be reliably known. An object of the present invention is to provide a deformation amount detection sensor and a method for measuring a maximum deformation amount of a structure using the same.

[0009]

Means for Solving the Problems In order to achieve the above object, the invention of claim 1 of the present application provides a base made of a material having a low yield point and a conductive material provided on the base in an electrically insulated state. A maximum value storage type deformation amount detection sensor characterized by having a resistor in which particles are dispersed in a polymer.

In the invention of claim 2 of the present application, the gist is a maximum value storage type deformation amount detection sensor according to claim 1, wherein the base material has a sheet shape.

In the invention of claim 3 of the present application, the gist is that the substrate is a tape-shaped maximum value storage type deformation amount detection sensor according to claim 1 or 2.

In the invention according to claim 4 of the present application, the resistor provided on the base material is divided into a plurality of pieces so that adjacent resistors are connected to each other by an electric conductor, and a pair of lead wires is connected to the resistor. Is connected to the maximum value storage type deformation amount detection sensor according to any one of claims 1 to 3.

According to a fifth aspect of the present invention, the divided resistors are provided in the longitudinal direction of the substrate for each of a plurality of blocks, and a pair of lead wires are provided for each of the blocks. The gist of the invention is a maximum value storage type deformation amount detection sensor according to any one of claims 1 to 3.

According to a sixth aspect of the present invention, in the maximum value storage type deformation amount detecting sensor according to any one of the first to fifth aspects, the base material is formed by annealing a metal. The gist is that there is.

According to a seventh aspect of the present invention, the base material is formed by annealing aluminum metal.
The gist is that the sensor is a maximum value storage type deformation amount detection sensor according to any one of the above items (1) to (6).

In the invention of claim 8 of the present application, the base material has an attachment member provided at both ends of the base material and having an attachment hole formed therein. The gist is a maximum value storage type deformation amount detection sensor.

According to the ninth aspect of the present invention, the resistor includes:
9. A printing ink formed by mixing and dispersing conductive particles in a solvent solution of a polymer to form a printing ink, and applying and printing the printing ink on a substrate. The gist is a maximum value storage type deformation amount detection sensor.

According to the tenth aspect of the present invention, the conductive particles used for the resistor include carbon black, graphite, activated carbon, carbon fiber, carbon whisker, fullerene, carbon nanotube, metal powder, metal foil, metal fiber, insulating fiber. One or a mixture of two or more of those in which carbon is applied to the surface of body beads or microbeads, and in which fine particles of insulating material such as mica and potassium titanate are made conductive by chemical plating, CVD or PVD. The gist is a maximum value storage type deformation amount detection sensor according to any one of claims 1 to 9.

In the eleventh aspect of the present invention, the polymer used for the resistor may be polyethylene, polypropylene,
Acrylic resin, polyester, nylon, polyvinyl chloride, polyvinylidene chloride, fluororesin, polyvinyl acetate, polystyrene, polymethyl methacrylate, polyethyl methacrylate, polyhydroxymethyl methacrylate,
Polyvinyl alcohol, polyacrylonitrile, polyimide, polysulfone, polycarbonate, polyacetal, polyurethane, polyphenylene oxide, polyxylene, polyformal, polybutyral, polyoxyethylene, polyoxymethylene (amorphous), copolymers of two or more of the above polymers, The maximum value storage type deformation amount detection sensor according to any one of claims 1 to 10, wherein the sensor is one or a mixture of two or more of rubbers, silicone resin, phenol resin, modified alkyd resin, and cellulose. It is a gist.

[0020] In the twelfth aspect of the present invention, the copolymer of two or more kinds of the polymers is a vinyl acetate-polyethylene copolymer, wherein the maximum value storage type deformation amount detection is performed. The gist is that it is a sensor.

According to a thirteenth aspect of the present invention, the protective member is provided on the surface of the substrate opposite to the surface on which the protective member is provided, and on the surface of the resistor. The gist is that the sensor is the maximum value storage type deformation amount detection sensor described in any one of the above items.

According to a fourteenth aspect of the present invention, the maximum value storage type deformation amount detection sensor according to any one of the first to thirteenth aspects is fixed to a surface of a detected member of a structure, and the maximum value storage is performed. The gist is to provide a method for measuring a deformation amount of a structure, characterized by examining a maximum elongation strain of a detected member using a mold deformation amount detection sensor.

In the invention of claim 15 of the present application, the terminals provided on the lead wires of the maximum value storage type deformation amount detection sensor are provided in a concentrated manner in a block unit in which a plurality of maximum value storage type deformation amount detection sensors are provided. The gist is to provide a method for measuring the amount of deformation of a structure, characterized in that the maximum elongation strain of a member to be detected can be intensively examined in block units at one place.

According to the present invention, a portable electric resistance measuring device is connected to a lead wire provided on a resistor of the maximum value storage type deformation amount detecting sensor to measure the electric resistance of the resistor. The gist of the invention is a method for measuring the amount of deformation of a structure according to claim 14 or 15, wherein the maximum elongation strain of the detected member is checked.

According to a seventeenth aspect of the present invention, the gist of the present invention is a method for measuring the amount of deformation of a structure according to the fifteenth aspect, wherein the electrical resistance measuring device has a CPU and a storage device.

In the eighteenth aspect of the present invention, a plurality of the maximum value storage type deformation amount detection sensors are fixed to the surface of the member to be detected, and a lead wire provided on a resistor of the maximum value storage type deformation amount detection sensor is electrically connected. The gist of the invention is a method for measuring the amount of deformation of a structure according to claim 15, wherein the method is connected to a computer provided with resistance measuring means and intensively checks the maximum elongation strain of the detected member.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a maximum value storage type deformation amount detecting sensor and a method of measuring a deformation amount of a structure using the same according to the present invention will be described with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, a maximum value storage type deformation detecting sensor 1 includes a base material 2 made of a material having a low yield point, and a conductive material provided on the base material 2 in an electrically insulated state. And a resistor 3 in which particles are dispersed in a polymer.

Further, an electrical insulating layer 4 is formed between the resistor 3 and the substrate 2 and a surface (back surface) of the substrate 2 opposite to the surface (front surface) on which the resistor 3 is formed. 2), a protective member 5 made of a synthetic resin is provided, and a protective member 6 is also provided on the surface of the resistor 3. The protection member 6 prevents the base member 2 from being corroded by electric corrosion when the maximum value storage type deformation amount detection sensor 1 is fixed to a steel frame or the like to be inspected. Is for preventing the resistor 3 from deteriorating in the environment.

The electric insulating layer 4 is not always necessary when the substrate 2 itself is an electric insulator.

The base material 2 is in the form of a sheet and in the form of an elongated tape. Further, the substrate 2 is made of a material having a low yield point, and is preferably made of an annealed metal, a synthetic resin, or the like, and particularly preferably an annealed aluminum.

In the case of a material whose yield stress cannot be clearly defined, the plastic strain is determined based on the deformation stress (0.2% proof stress) of 0.2% as shown in FIG. Use one with low proof stress.

The reason for using a material having a low yield point (small 0.2% proof stress) for the base material 2 is that even if the stress applied to the base material 2 is small, the base material 2 undergoes plastic deformation and even after the stress is removed. The permanent strain remains, and the resistor 3 provided on the substrate 2
This is to maintain a distorted (extended) state.

As the method of forming the resistor 3 on the base material and the constituent material, the constituent material disclosed in Japanese Patent Application Laid-Open No. H11-241903 is used, and the formation method on the base material is performed. For example, it is formed by applying and printing on the base material 2 using a printing method, and dissolving a polymer in a solvent.
The conductive particles are added thereto and mixed.

The solvent may be basically any solvent as long as it dissolves the polymer. Usually, xylene, decalin, tetralin or the like is used, and ink (conductive particle-polymer solution) is used.
Additives such as terpene oil, ethylene glycol, etc. may be added in small amounts to improve the elongation of the ink and to adhere to the printing fabric.

The conductive particles include carbon black, graphite,
Activated carbon, carbon fiber, carbon whisker, fullerene, carbon nanotube, metal powder, metal foil, metal fiber, insulator beads or microbeads with carbon added to the surface, mica, potassium titanate, etc. It is one or a mixture of two or more of those having conductivity by plating, CVD or PVD.

Polymers include polyethylene, polypropylene, acrylic resin, polyester, nylon, polyvinyl chloride, polyvinylidene chloride, fluororesin, polyvinyl acetate, polystyrene, polymethyl methacrylate, polyethyl methacrylate, and polyhydroxymethyl methacrylate. , Polyvinyl alcohol, polyacrylonitrile, polyimide, polysulfone, polycarbonate, polyacetal, polyurethane, polyphenylene oxide, polyxylene, polyformal, polybutyral, polyoxyethylene, polyoxymethylene (amorphous), copolymers of two or more of the above polymers , A rubber, a silicone resin, a phenol resin, a modified alkyd resin, and cellulose, or a mixture of two or more thereof.

As described above, the resistor 3 is made of plastic,
It is manufactured by dispersing conductive particles in a polymer such as rubber, and measures the elongation strain from the increase in the electric resistance when the resistor 3 is extended. A feature is that the sensor output is exponential with respect to strain. That is, when the elongation strain reaches a certain value, the resistance sharply increases.

In addition, in the resistor 3, the logarithm of the resistance value and the elongation strain have an almost linear relationship at any graphite concentration, and the exponential resistance increases at a carbon concentration of 30.0 wt%. As shown in FIG.
In the case of 2.5 wt%, the largest resistance increase is observed.
This phenomenon is considered to be due to the tunnel effect as described in the above-mentioned Japanese Patent Application Laid-Open No. H11-241903.

Although the linear relationship between the logarithm of the resistance value and the elongation strain is clear, there is also an influence of the carbon concentration on this relationship. When the resistance is increased per unit elongation strain when the carbon concentration is changed and the resistor is pulled, as shown in FIG. 5, the resistance has a maximum value around 30 wt%. That is, FIG. 5 shows that the resistance value when the strain amount is a certain value is R ₀ , the unit strain amount (ε) is R when the sample is elongated, and the resistance value ratio is a function of the carbon concentration. It is a plot.

Therefore, if a concentration around 30 wt% is selected, it becomes possible to manufacture a strain sensor which is most sensitive to elongation strain. This carbon concentration and [(R / R
₀ ) / ε] can be explained as follows. That is,
When the carbon concentration is low, the gap between the particles is wide, so that the potential barrier is high in many cases, and the tunnel current is extremely low, and virtually no current is observed. Therefore, even if such a resistor is expanded, the resistance value cannot be expected to increase so much. Conversely, when the carbon concentration is high, the particles are in direct contact and the contribution by the tunnel effect is small. Therefore, FIG.
It is quite predictable that the maximum value appears at a certain carbon concentration as shown in FIG.

The maximum value storage type deformation amount detection sensor 1 is composed of a base material 2 made of a material having a low yield point, in which conductive particles are dispersed in a polymer, and when the strain reaches a certain value, the resistance rapidly increases. When the base member 2 receives a certain level of stress or more, the base member 2 undergoes plastic deformation and permanent deformation occurs, and the permanent strain is generated. Maintain a distorted (extended) state.

Accordingly, the expanded resistor 3 exhibits a resistance value corresponding to the elongation as shown in FIG. 4, and the maximum deformation of the inspected member to which the maximum value storage type deformation amount detecting sensor 1 is attached. You can know the quantity.

Incidentally, the maximum value storage type deformation amount detection sensor 1
In order to keep the substrate fixed to the structure for a long period of time, the maximum value storage type deformation amount detection sensor 1 may be fixed to the structure using a strong adhesive, but as shown in FIG. Attachment members 7 are fixedly formed at both ends of the second member 2, attachment holes 7 a are formed in the attachment members 7, the attachment holes 7 a are engaged with attachment bolts welded to the structure, and nuts are used. It is preferable to screw together and fix it together with an adhesive. In addition, lead wires 8 provided with connection terminals 8 a are provided from both ends of the resistor 3 so as to avoid the attachment member 7.

Further, in the above embodiment, the ribbon-shaped 1
Although one resistor and a pair of lead wires are provided on one base material, as shown in FIG. 6, an electric conductor, for example, an Ag film 13 is provided on the resistor 12 at regular intervals. Forming
The portion where the Ag film 13 is formed is short-circuited, and the resistor 12
Is divided into a resistor 12a having a small length.
The maximum value storage type deformation amount detection sensor 11 for a substantially long resistor can be manufactured, and the maximum deformation amount of a long inspected member can be known.

As shown in FIG. 7, for example, an Ag film 23 is formed on the resistor 22 at a predetermined interval, and the portion where the Ag film 23 is formed is short-circuited to form the resistor 22. The resistors 22a are divided into small-length resistors 22a, and the divided resistors 22a are defined as one block 24.
A pair of lead wires 25 is provided for every four
By forming the sensor, it is possible to manufacture the substantially long maximum value storage type deformation amount detection sensor 21 of the resistor, and to know the maximum deformation amount and the position of the long member to be inspected.

Next, a method for measuring the deformation amount of a structure using the maximum value storage type deformation amount detection sensor 1 will be described.

A deformation amount of a structure, for example, a steel frame used for a high-rise building as shown in FIG. 8 is measured. Column length (L
1) pillar pillar (D1) and beam length (L2)
In the design of the steel frame assembled to be the beam (D2) (the holding strength design), the area where plasticization is assumed is L / 10 or 2D or more from the column or beam end. As shown in FIG. 9, the range in which the strain needs to be measured with particular emphasis is about D from the column or beam end, and the deformation is concentrated particularly from the column or beam end to D / 2.

The standard of the dimensions of general steel materials used for high-rise buildings is a four-story (approximately 14 m high) pillar and a beam is approximately D = 300 mm, and a 14-story (approximately 64 m high) pillar. D = 700mm for beam, 37 stories (height: 173m) pillar, D = 800-10 for beam
It is about 00 mm.

Therefore, as a representative inspection point, the maximum value storage type deformation amount detection sensor 1 is fixed at a position as shown in FIG.

The deformation amount of the structure is measured, for example, after a large earthquake or the like, as shown in FIG.
This is performed using By connecting the connection terminal 31a provided on the electric resistance measuring device 31 to the connection terminal 8a provided on the maximum value storage type deformation amount detection sensor 1, and measuring the partial pressure of the shunt resistance Rs, the maximum value storage type deformation is obtained. The resistance value Rc of the quantity detection sensor 1 can be obtained.

That is, i = E / (Rc + Rs), V =
iRs = ERs / (Rc + Rs), where Rc + Rs =
ERs / V, Rc = E / VRs-Rs, therefore Rc =
The resistance value Rc of the maximum value storage type deformation amount detection sensor 1 can be obtained as Rs (E / V-1).

From the resistance value Rc thus obtained,
For example, if a strain-resistance curve diagram as shown in FIG. 18 for the member to be inspected is created in advance, the member to be inspected to which the maximum value storage type deformation amount detection sensor 1 is attached is used by using this curve diagram. The maximum deformation can be checked. If the strain-tensile stress diagram as shown in FIG. 15 is created in advance by examining the maximum deformation amount, the member to be inspected is plastically deformed or elastically deformed using this diagram. It is possible to know whether or not there was, and to know the degree of danger of the structure. Therefore, the use of buildings with columns or beams that have undergone plastic deformation has been discontinued, and
The next disaster can be avoided properly.

Also, a plurality of terminals of the lead wires of the maximum value storage type deformation amount detection sensor provided for each block such as a building floor or a room unit are provided in a block unit, and this terminal is shown in FIG. Electrical resistance measuring device 3 as shown
By connecting 1, the maximum elongation strain of the detected member can be checked at one location in block units such as building floors or room units.

If the strain-resistance curve diagram and the strain-tensile stress diagram of the member to be inspected are stored in advance in the storage device of the computer, the measured resistance value is input to the computer after the inspection. In addition, the maximum deformation amount of the inspected member, the presence or absence of plastic deformation, and the like can be automatically checked.

Further, as shown in FIG. 11, when the structure is a wooden house, stress is applied to the beam 42, the column 43, and the horizontal member 44 of the wooden house 41 due to an earthquake or the like. Even if a crack enters the inside of the frame member 44, this crack cannot be found by visual inspection from the outside, but the maximum value storage type deformation amount attached to the beam 42, the column 43, and the horizontal member 44, which are the members to be inspected. By measuring the electric resistance value of the detection sensor 1, the maximum deformation amount of the beam 42, the column 43, and the horizontal member 44 is checked, and it is determined whether or not the beam 42, the column 43, and the horizontal member 44 are cracked. It is possible to know the degree of danger of the wooden house 41. Therefore, the use of the wooden house 41 having the cracked beam 42, the pillar 43, and the horizontal member 44 therein can be stopped, and a secondary disaster due to aftershocks or the like can be properly avoided.

Further, if the maximum value storage type deformation amount detection sensor 1 is attached to a beam or a pillar as a member to be inspected before the structure is assembled, the electric resistance of the maximum value storage type deformation amount detection sensor 1 after the assembly is assembled. By measuring, it is possible to know that a large load is applied to the member during assembly, strain is generated, the internal stress is applied to the structure, and the structure is in a dangerous state.

[0058]

(Test 1) Using a maximum value storage type deformation amount detection sensor according to the present invention as shown in FIG. 12 (however, no mounting member is provided, and fixed by an adhesive) (Example 1), The specimen was fixed to a flat steel as shown below, and a tensile test was performed to examine the relationship between tensile stress-strain, tensile stress-electric resistance, and strain-electric resistance.

(1) Flat steel: has a load-strain curve as shown in FIG. 13, is equivalent to material SS400, has a physical difference shape, and each dimension is as shown in FIG.

(2) Sensor: having a shape as shown in FIG. 12, having an initial electric resistance value of 8,082Ω and a resistor width of 4 m
m, length 100 mm.

(3) Measurement: As shown in FIGS. 12 and 14, a maximum value storage type deformation amount detection sensor is bonded to the center of a flat steel plate with a strong adhesive,
Three commonly used strain gauges were bonded at positions corresponding to the upper and lower portions.

(4) Force: 20 tf as shown in FIG.
Use an instro universal testing machine.

(5) Result: FIG. 15 shows the average (average of three measurement points) flat steel tensile stress-strain relationship. The tensile stress-strain characteristic peculiar to steel was shown.

FIG. 16 shows the relationship between the average flat steel tensile stress and the electric resistance value. It was found that when the tensile stress of the flat steel reached 30 kg / cm ² , the resistance value of the maximum value storage type deformation amount detection sensor rapidly increased to 370% of the initial resistance value as shown in FIG.

FIG. 1 shows the relationship between average strain and electric resistance.
8 and FIG. 19 is an enlarged view of a portion A in FIG. In Example 1, it was found that the electric resistance sharply increased from about 1,500 μm, confirming its usefulness as a sensor. It was found that the maximum elongation strain of the flat steel was maintained (stored) by the permanent strain of the substrate, and that the maximum deformation could be checked by measuring the electric resistance of the maximum storage type deformation detection sensor.

(Test 2) A maximum value storage type deformation amount detecting sensor according to the present invention in which the electrodes are provided in the longitudinal direction of the resistor shown in FIG. Using Example 2), a test similar to Test 1 was performed, and the relationships among tensile stress-strain, tensile stress-electric resistance, and strain-electric resistance were examined.

(1) Flat steel: The material is equivalent to material SS400, and it has a physical difference shape and each dimension is as shown in FIG.

(2) Sensor: initial electric resistance value 100
Ω, resistor width 302 mm, length 30 mm.

(3) Measurement: As shown in FIG. 21, a maximum value storage type deformation amount detection sensor was bonded to the center of a flat steel plate with a strong adhesive, and five strain gauges were fixed to the back surface.

(4) Results: FIG. 22 shows the relationship between the tensile stress and the electric resistance value of the flat steel at the average of five measurement points. It was found that when the tensile stress of the flat steel became 7 kg / cm ² , the resistance value of the maximum value storage type deformation amount detection sensor rapidly increased.

FIG. 23 shows the relationship between the strain and the electric resistance value at the average of the five measurement points. FIG.
Shown in In Example 2, it was found that the electrical resistance sharply increased from 1,550 μm, and the usefulness as a sensor could be confirmed even if electrodes were provided in the longitudinal direction of the resistor. It was found that the maximum elongation strain of the flat steel was maintained (stored) by the permanent strain of the substrate, and that the maximum deformation could be checked by measuring the electric resistance of the maximum storage type deformation detection sensor.

(Test 3) A test similar to Test 1 (Example) using a maximum value storage type deformation amount detection sensor according to the present invention as shown in FIG. 25 (provided that no mounting member is provided and an adhesive is used). 3) and a test in which a repeated load (Example 4) was applied.

(1) Flat steel: In both Examples 3 and 4, the material is equivalent to SS400 in the same manner as in Test 1, and has a dumbbell shape with dimensions as shown in FIG.

(2) Sensor: In Examples 3 and 4,
It has a shape as shown in FIG. 25 and has a resistor width of 40 mm and a length of 4.5 mm.

(3) Measurement: For both the third and fourth embodiments, FIG.
As shown in FIG. 6, the maximum value storage type deformation amount detection sensor was bonded to the center of one surface of the flat steel with a strong adhesive, and two strain gauges were fixed above and below the sensor.

(4) Loading: The loading method was as shown in Table 1. In Example 3, simple loading and Example 4 were repeated loading.

[0077]

[Table 1]

(5) Results: FIG. 27 shows the relationship between the tensile stress and the strain of Example 3 (typically measured values on the upper gauge). The tensile stress-strain characteristic peculiar to steel was shown.

Tensile Stress Due to Repeated Loading in Example 4
FIG. 28 shows the relationship between the strain (typically the measured value of the upper gauge).

FIG. 29 shows the relationship between the tensile stress and the electric resistance in Example 3. Tensile stress on flat steel is 28kg / c
When becomes m ^2, increasing the maximum value stored-deformation amount detection sensor resistance abruptly reached 50 M.OMEGA, the resistance value as shown in FIG. 30 became 16,000% of the initial resistance value.

FIG. 31 shows the relationship between the tensile stress and the electric resistance in Example 4. Tensile stress on flat steel is 28kg / c
When becomes m ^2, the resistance value of the maximum value memory type deformation amount detection sensor is rapidly increased. At this time, the resistance value is 1.2 MΩ. When the load is repeatedly applied, a residual resistance occurs when the tensile stress is reduced to 0. However, when the load is applied repeatedly as shown in FIG. 32, the resistance value becomes 2,000%, Up to 4,0
It was found to increase to 00%.

FIG. 33 shows the relationship between the tensile stress (average value measured by the upper and lower gauges) and the increase in the electric resistance value in Example 3. The resistance value increases rapidly due to the occurrence of strain.

FIG. 34 shows the relationship between the tensile stress (mean value measured by the upper and lower gauges) due to the repeated loading and the electric resistance value in Example 4. The resistance value sharply increases due to the occurrence of the strain of 2,000 μm. A large resistance value is maintained even if the strain is changed by repeated loading.

In both Examples 3 and 4, it was found that the electrical resistance increased sharply from the amount of strain, confirming its usefulness as a sensor. It was found that the maximum elongation strain of the flat steel was maintained (stored) by the permanent strain of the substrate, and that the maximum deformation could be checked by measuring the electric resistance of the maximum storage type deformation detection sensor.

[0085]

According to the maximum value storage type deformation amount detection sensor and the method of measuring the deformation amount of a structure using the same according to the present invention, the structure is simple, easy to handle, inexpensive, and has the maximum deformation of the structure. It is possible to provide a maximum deformation amount detection sensor capable of reliably knowing the amount and a method of measuring the maximum deformation amount of a structure using the sensor.

That is, the maximum value storage type deformation amount detection sensor includes a base made of a material having a low yield point, and a resistor provided on the base in an electrically insulated state and having conductive particles dispersed in a polymer. Therefore, the past maximum elongation strain amount of the member to be inspected is left as a permanent strain in the base material where the plastic deformation has occurred, the resistor is maintained in a distorted (extended) state, and the resistance is measured. Thus, the past maximum elongation strain amount of the inspected member can be checked.

Further, since the base material is in a sheet shape, the formation of the resistor on the base material and the mounting of the member to be inspected of the maximum value storage type deformation amount detection sensor can be easily and reliably performed.

Further, since the base material is in a tape shape, the formation of the resistor on the base material and the mounting of the maximum value storage type deformation amount detection sensor on the member to be inspected can be performed easily and reliably, and the relatively long base material can be used. Inspection of the inspection member can be easily performed.

Further, the resistor provided on the base material is divided into a plurality of pieces so that adjacent resistors are connected by an electric conductor, and a pair of lead wires is connected to the resistor. Even when it is difficult to manufacture a long resistor having a uniform resistance, a long maximum value storage type deformation amount detection sensor can be manufactured, and a long member to be inspected can be easily and accurately inspected.

Further, since the divided resistors are arranged in the longitudinal direction of the substrate for each of a plurality of blocks, and a pair of lead wires are provided for each of the blocks, a long resistor having a uniform resistance can be manufactured. Even when it is difficult to do so, a long maximum value storage type deformation amount detection sensor can be manufactured, and the maximum deformation amount of a long inspected member and its position can be known.

Further, since the base material is formed by annealing metal, the yield point can be lowered, and even if the stress applied to the member to be inspected is small, permanent deformation occurs in the base material due to plastic deformation. The maximum elongation strain can be surely checked.

Further, since the base material is formed by annealing aluminum metal, the resistor can be easily formed on the base material by printing, and a ribbon-shaped base material can be manufactured more easily. A storage type deformation amount detection sensor can be manufactured.

Further, since the base material has mounting members provided at both ends of the base material and having mounting holes formed therein, the maximum value storage type deformation amount detecting sensor is securely fixed to the member to be inspected for a long time. I can put it.

Also, the resistor is formed by mixing and dispersing conductive particles in a solvent solution of a polymer to form a printing ink, and applying and printing this printing ink on a base material, and thus is suitable for mass production.

Further, the conductive particles used for the resistor include:
Carbon black, graphite, activated carbon, carbon fiber, carbon whiskers, fullerenes, carbon nanotubes,
Chemical plating, CVD on metal powder, metal foil, metal fiber, insulating beads or microbeads with carbon on the surface, fine particles of insulating material such as mica, potassium titanate
Alternatively, since it is one or a mixture of two or more types that have been given conductivity by PVD treatment, the maximum elongation strain remaining on the substrate can be accurately displayed as an electric resistance value.

The polymer used for the resistor includes polyethylene, polypropylene, acrylic resin, polyester, nylon, polyvinyl chloride, polyvinylidene chloride,
Fluororesin, polyvinyl acetate, polystyrene, polymethyl methacrylate, polyethyl methacrylate, polyhydroxymethyl methacrylate, polyvinyl alcohol, polyacrylonitrile, polyimide, polysulfone, polycarbonate, polyacetal, polyurethane, polyphenylene oxide, polyxylene, polyformal, One or a mixture of two or more of polybutyral, polyoxyethylene, polyoxymethylene (amorphous), copolymers of two or more of the above polymers, rubbers, silicone resins, phenolic resins, modified alkyd resins, and cellulose Therefore, the maximum elongation strain remaining on the substrate can be accurately displayed as an electric resistance value.

Since the copolymer of two or more polymers is a vinyl acetate-polyethylene copolymer, the maximum elongation strain remaining on the substrate can be accurately displayed as an electric resistance value.

Further, since the protective member is provided on the surface of the substrate opposite to the surface on which the protective member is provided and on the surface of the resistor, the long-term maximum value storage type deformation detecting sensor is fixed to the structure. Even if it does, the base material will not be corroded by the electrolytic corrosion, and the resistor will not be degraded in the environment.

Further, since the maximum value storage type deformation amount detection sensor according to the present invention is fixed to the surface of the detected member and the maximum elongation strain of the detected member is checked, it is possible to surely know the maximum elongation strain of the structure. This makes it possible to accurately determine whether or not the structure can be used safely thereafter.

Also, the terminals provided on the lead wires of the maximum value storage type deformation amount detection sensor are concentrated on a block unit where a plurality of maximum value storage type deformation amount detection sensors are provided, and the block is provided at one location. Since the maximum elongation strain of the detected member can be intensively checked, the maximum elongation strain of the detected member at a plurality of locations can be easily and quickly checked.

Also, since a portable electric resistance measuring device is connected to a lead wire provided on a resistor of the maximum value storage type deformation detecting sensor, the elongation strain of the detected member is measured.
The resistance value can be read easily and easily with an electric resistance measuring device, and the maximum elongation strain of the structure can be surely known, so that it is possible to accurately determine whether or not the structure can be used safely thereafter.

Further, since the electric resistance measuring device has a CPU and a storage device, the resistance values are read from a plurality of maximum value storage type deformation amount detecting sensors and stored, and the elongation strain information is read from the electric resistance measuring device to a computer. , Can be centrally managed.

Further, a plurality of maximum value storage type deformation amount detection sensors are fixed to the surface of the member to be detected, and a computer is connected to a lead wire provided on a resistor of the maximum value storage type deformation amount detection sensor to collectively. Since the maximum elongation strain of the detected member is checked, the maximum elongation strain of the structure can be centrally controlled, and it is possible to accurately determine whether or not the structure can be used safely thereafter.

[Brief description of the drawings]

FIG. 1 is a plan view of a maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 2 is a cross-sectional view of the maximum value storage type deformation amount detection sensor according to the present invention shown in FIG. 1 along the line II-II.

FIG. 3 is a diagram showing a relationship between tensile stress and elongation strain of a material used for a substrate used in the present invention.

FIG. 4 shows the logarithm of the electric resistance of the resistor used in the present invention.
FIG. 4 is a diagram showing a relationship between elongation rates.

FIG. 5 is a diagram showing a relationship between a resistance increase ratio per unit elongation strain and a carbon concentration of a resistor used in the present invention.

FIG. 6 is an explanatory diagram showing another embodiment of a maximum value storage type deformation amount detection sensor according to the present invention and a measurement state thereof.

FIG. 7 is an explanatory diagram showing another embodiment of a maximum value storage type deformation amount detection sensor according to the present invention and a measurement state thereof.

FIG. 8 is an explanatory diagram for explaining a sensor mounting position in a method of measuring a deformation amount of a structure using a maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 9 is an explanatory diagram for explaining a sensor mounting position in a method of measuring a deformation amount of a structure using a maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 10 is an explanatory view of an electric resistance measuring device used in the method for measuring the amount of deformation of a structure according to the present invention.

FIG. 11 is an explanatory diagram showing another embodiment of a maximum value storage type deformation amount detection sensor according to the present invention and a measurement state thereof.

FIG. 12 is an explanatory diagram of a test method in which the embodiment using the maximum value storage type deformation amount detection sensor according to the present invention is attached to a member to be measured.

FIG. 13 is a load-strain diagram of a member to be measured used in a maximum deformation amount measurement test using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 14 is an explanatory diagram of a test method using a maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 15 is a tensile stress-strain diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 16 is a tensile stress-electric resistance diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 17 is a tensile stress-electric resistance increment ratio diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 18 is an electric resistance increment ratio-strain diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 19 is a diagram showing details of a portion A in FIG. 18;

FIG. 20 is an explanatory diagram of an embodiment of a maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 21 is an explanatory diagram of a test method using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 22 is a load-electric resistance result diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 23 is an electric resistance increment ratio-strain diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 24 is a diagram showing details of a portion B in FIG. 23;

FIG. 25 is an explanatory diagram of an embodiment of a maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 26 is an explanatory diagram of a test method using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 27 is a tensile stress-strain diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 28 is a tensile stress-strain diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 29 is a tensile stress-electric resistance diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 30 is a tensile stress-electrical resistance increment ratio diagram of test results using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 31 is a tensile stress-electric resistance diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 32 is a tensile stress-electric resistance increment ratio diagram of test results using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 33 is a strain-electric resistance increment ratio diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

FIG. 34 is a strain-electric resistance increment ratio diagram of a test result using the maximum value storage type deformation amount detection sensor according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Maximum value storage type deformation amount detection sensor 2 Base material 3 Resistor 4 Electrical insulating layer 5 Protective member 6 Protective member 7 Mounting member 7a Mounting hole 8 Lead wire 8a Connection terminal 11 Maximum value storage type deformation amount detection sensor 12 Resistor 12a Resistor 13 Ag film 21 Maximum value storage type deformation amount detection sensor 22 Resistor 22a Resistor 23 Ag film 24 Resistor block

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Keiichi Masai Building No.601 No.601, 1-3 Building 3-6-6, Nagareyama-shi, Chiba Prefecture (72) Inventor Toshio Abe 1-2-1, Otemachi 1-2-chome, Chiyoda-ku, Tokyo Inside Maruha Corporation (72) Inventor Tsuneo Midorikawa 2-5-1 Komagata, Taito-ku, Tokyo F-term (reference) 2F063 AA25 AA50 BA14 CA40 DA02 DD02 DD06 FA12 FA14 FA16 FA18 LA17 ZA01

Claims (18)

[Claims] 1. A maximum value comprising: a base made of a material having a low yield point; and a resistor provided on the base in an electrically insulated state and having conductive particles dispersed in a polymer. Memory type deformation amount detection sensor. 2. The maximum value storage type deformation amount detection sensor according to claim 1, wherein the substrate has a sheet shape. 3. The maximum value storage type deformation amount detection sensor according to claim 1, wherein the base material has a tape shape. 4. A resistor provided on the base material is divided into a plurality of pieces so that adjacent resistors are connected by an electric conductor, and a pair of lead wires is connected to the resistor. The maximum value storage type deformation amount detection sensor according to any one of claims 1 to 3, wherein: 5. The divided resistor is provided in the longitudinal direction of the substrate for each of a plurality of blocks, and a pair of lead wires is provided for each of the blocks.
4. The maximum value storage type deformation amount detection sensor according to any one of items 3 to 3. 6. The maximum value storage type deformation amount detecting sensor according to claim 1, wherein the base material is formed by annealing a metal. 7. The maximum value storage type deformation amount detection sensor according to claim 1, wherein the base material is formed by annealing aluminum metal. 8. The maximum value storage type deformation according to any one of claims 1 to 7, wherein the base material has mounting members provided at both ends of the base material and having mounting holes formed therein. Quantity detection sensor. 9. The resistor is formed by mixing and dispersing conductive particles in a solvent solution of a polymer to form a printing ink, and applying and printing the printing ink on a base material. 9. The maximum value storage type deformation amount detection sensor according to any one of 1 to 8. 10. The conductive particles used for the resistor include carbon black, graphite, activated carbon, carbon fiber,
Carbon whiskers, fullerenes, carbon nanotubes, metal powders, metal foils, metal fibers, insulator beads or microbeads with carbon added to the surface, mica,
Chemical plating on insulating fine pieces such as potassium titanate, C
The maximum value storage type deformation amount detection sensor according to any one of claims 1 to 9, wherein the sensor is one or a mixture of two or more of those provided with conductivity by VD or PVD processing. 11. The polymer used for the resistor is polyethylene, polypropylene, acrylic resin, polyester, nylon, polyvinyl chloride, polyvinylidene chloride, fluororesin, polyvinyl acetate, polystyrene, polymethyl methacrylate, polymethacryl. Ethyl acid, polyhydroxymethyl methacrylate, polyvinyl alcohol,
Polyacrylonitrile, polyimide, polysulfone, polycarbonate, polyacetal, polyurethane, polyphenylene oxide, polyxylene, polyformal,
One or a mixture of two or more of polybutyral, polyoxyethylene, polyoxymethylene (amorphous), copolymers of two or more of the above polymers, rubbers, silicone resins, phenolic resins, modified alkyd resins, and cellulose The maximum value storage type deformation amount detection sensor according to claim 1. 12. The copolymer of two or more kinds of the polymers,
The maximum value storage type deformation amount detection sensor according to claim 11, wherein the sensor is a vinyl acetate-polyethylene copolymer. 13. The protection member according to claim 1, wherein a protection member is provided on a surface of the substrate opposite to a surface on which the protection member is provided, and on a surface of the resistor. Maximum value storage type deformation amount detection sensor. 14. The maximum value storage type deformation amount detection sensor according to claim 1 is fixed to a surface of a detected member of a structure, and the maximum value storage type deformation amount detection sensor is provided. A method for measuring a deformation amount of a structure, wherein a maximum elongation strain of a member to be detected is checked using the method. 15. A terminal provided on a lead wire of the maximum value storage type deformation amount detection sensor is provided in a block unit in which a plurality of maximum value storage type deformation amount detection sensors are provided. A method for measuring the amount of deformation of a structure, wherein the maximum elongation strain of a member to be detected can be intensively examined by the method. 16. A member to be detected by connecting a portable electric resistance measuring device to a lead wire provided on the resistor of the maximum value storage type deformation amount detection sensor and measuring the electric resistance of the resistor. The method for measuring the amount of deformation of a structure according to claim 14 or 15, wherein the maximum elongation strain is examined. 17. The method according to claim 15, wherein the electrical resistance measuring device has a CPU and a storage device. 18. An electric resistance measuring means, wherein a plurality of the maximum value storage type deformation amount detection sensors are fixed to the surface of a member to be detected, and a lead wire provided on a resistor of the maximum value storage type deformation amount detection sensor is provided. The method for measuring the amount of deformation of a structure according to claim 15, wherein the method is connected to a computer, and checks the maximum elongation strain of the detected member intensively.