Moisture content measurement sensor installation system into concrete, moisture content measurement sensor installation tool into concrete, and moisture content measurement sensor installation method into concrete

Abstract

To provide a technology for installing an electrode-embedded substrate electrode sensor at a predetermined position inside concrete to measure a moisture content of the concrete.SOLUTION: A moisture content measurement sensor installation tool 1 is composed of: a formwork side fixing jig 10 attached to a formwork 2 used for placing concrete; and a sensor side fixing jig 20 attached to a sensor 3 measuring a moisture content of the concrete. The moisture content measurement sensor installation tool can assume two states: a first state before placing concrete, in which the sensor is held and attached to the formwork by connecting a frame side fixing jig attached to the formwork with the sensor side fixing jig to which the sensor is attached, and a second state after placing concrete, in which the formwork side fixing jig and the sensor side fixing jig are separated and the formwork side fixing jig is removed from the formwork, to leave the sensor side fixing jig together with the sensor embedded at a predetermined position inside the concrete.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a moisture content measurement sensor installation system for inside concrete, a moisture content measurement sensor installation tool for inside concrete, and a method for installing a moisture content measurement sensor inside concrete, in which a sensor for measuring the moisture content of concrete is left in a predetermined position inside the concrete in order to measure the moisture inside a structure (moisture content of concrete) over a long period of time after the concrete has been poured. [Background technology]

[0002] Today, with the growing demand for a sustainable society, proper maintenance and utilization of buildings are required, and in order to achieve this proper maintenance and management, it is becoming increasingly important to measure the moisture content inside structures after concrete has been poured.

[0003] In other words, the service life of a reinforced concrete structure generally depends on the number of years it takes for the carbonation of concrete to reach the rebar, but it is known that the progress of carbonation is greatly influenced by the moisture content of the concrete. It is also known that the corrosion rate of rebars is affected by moisture, and in surveys of actual structures, it has been reported that even if carbonation has reached the rebars, the rebars do not corrode if the moisture content of the concrete near the rebars is low.

[0004] The moisture content of a concrete is generally calculated by drying a sample at 105°C, and dividing the mass of the sample by the mass of the dried sample to determine the amount of evaporated water. Therefore, to measure the moisture content, a sample piece must be taken from the actual structure without using water. Therefore, electrical methods have been proposed as a technique for easily and non-destructively measuring the moisture content of concrete structures.

[0005] The electrical method utilizes the fact that the electrical properties of concrete change depending on the moisture content. By measuring the electrical resistance or capacitance, the moisture content of the concrete can be estimated from the relationship (calibration curve) between these electrical characteristic values ​​and the moisture content of the concrete, which has been determined in advance.

[0006] As one of the electrical methods, an electrode-embedded method has been proposed in which an electrode sensor is embedded in the concrete to measure the electrical resistance or capacitance and estimate the moisture content of the concrete. Here, as an electrode sensor to be embedded inside concrete, for example, a substrate electrode sensor has been proposed which has parallel measurement electrodes facing the measurement surface of the concrete structure, and which is equipped with a measurement substrate unit which forms a capacitor between the measurement object and the measurement electrodes and measures the impedance corresponding to the water content of the measurement object as a detection signal, and a data output electrode which outputs the detection signal (see, for example, Patent Document 1).

[0007] In this electrode-embedded method, an electrode sensor is embedded inside the concrete, making it possible to measure the moisture content of the concrete over a long period of time. However, technology is required to easily and accurately embed the substrate electrode sensors in predetermined locations at construction sites, etc., and their application is currently limited to research purposes.

[0008] As an electrical method, an electrode insertion type means is also known, which is composed of a cylindrical pipe that forms a capacitor area with capacitance and a rod-shaped sensor body with multiple sensor electrodes, and by inserting the sensor body into the pipe, a detection signal corresponding to the capacitance of the capacitor area is detected and the moisture content of the concrete is estimated (see, for example, Patent Document 2).

[0009] This electrode insertion method does not require the electrodes to be embedded in the concrete beforehand, making it possible to carry out measurements easily. However, it is inappropriate to use the same pipe repeatedly for a long period of time, and it is not suitable for measuring the change in moisture content over time.

[0010] Although various methods for measuring the moisture content of concrete have been proposed, a general-purpose method that allows for long-term measurement over time has not yet been established. Specifically, the following challenges exist in order to easily and accurately embed a substrate electrode sensor in a predetermined position at a construction site, etc. The substrate electrode sensor can be easily installed in the formwork before pouring concrete. To easily separate a substrate electrode sensor from a formwork after pouring concrete, and to leave the substrate electrode sensor in a predetermined position. The substrate electrode sensor must be able to withstand the impact of the concrete flowing during concrete pouring and remain in the correct position. Moisture content measurement must be easily accessible from the wall of the concrete structure. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Patent Publication No. 2021-196180 [Patent Document 2] Patent No. 6774100 Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention was developed in consideration of the above-mentioned conventional circumstances, and aims to provide a technology for easily installing an electrode-embedded type substrate electrode sensor at a predetermined position inside concrete to measure the moisture content of the concrete, in a moisture content measurement technology that uses an electrode-embedded type electrical method using a substrate electrode sensor. [Means for solving the problem]

[0013] In order to achieve the above-mentioned object, a first aspect of the present invention is a moisture content measurement sensor installation system inside concrete, comprising: a formwork used for pouring concrete; an electrode-embedded sensor for measuring the moisture content of the concrete; and sensor installation means used to install the sensor at a predetermined position inside the concrete, wherein the sensor installation means can assume two states: a first state before concrete is poured, in which the sensor installation means is attached to the formwork while holding the sensor; and a second state after concrete is poured, in which the sensor installation means is removed from the formwork while leaving the sensor inside the concrete.

[0014] In other words, the system according to the present invention is based on the use of a sensor installation means for holding an electrode-embedded sensor that measures the moisture content of concrete so that the sensor is left in a predetermined position inside the concrete during the process of constructing a concrete structure.

[0015] In the above system, the sensor installation means is composed of a formwork-side fixing jig attached to the formwork, a sensor-side fixing jig attached to the sensor, formwork fixing means for attaching the formwork-side fixing jig to the formwork, sensor fixing means for attaching the sensor-side fixing jig to the sensor, and jig connecting means for connecting the formwork-side fixing jig and the sensor-side fixing jig, and in the first state, the formwork-side fixing jig is attached to the formwork using the formwork fixing means, and the sensor-side fixing jig is attached to the sensor using the sensor fixing means and connected to the formwork-side fixing jig using the jig connecting means, and in the second state, the formwork-side fixing jig is removed from the formwork by releasing the formwork fixing means, and the sensor-side fixing jig is separated from the formwork-side fixing jig by releasing the jig connecting means and is left attached to the sensor in the concrete poured inside the formwork.

[0016] Furthermore, in the above system, the formwork-side fixing jig comprises a cylindrical formwork insertion portion having a length equal to the length in the thickness direction of the formwork, an annular formwork mounting portion provided so as to expand on one end side of the formwork insertion portion and attached in contact with the outer surface of the formwork, a flat sensor-side jig mounting portion provided so as to close the other end side of the formwork insertion portion and enabling the sensor-side fixing jig to be attached on the inner surface side of the formwork, an opening provided so as to penetrate the sensor-side jig mounting portion and allowing a connecting portion for electrically connecting the sensor to a measuring device main body to be inserted, and a formwork receiving means provided so as to penetrate the formwork mounting portion. and a jig connector receiving portion for receiving the jig connecting means provided to penetrate the sensor-side jig mounting portion, and the sensor-side fixing jig can have a sensor holding portion attached near the connection portion of the sensor, a sensor fixing portion for receiving the sensor fixing means provided to penetrate the sensor holding portion and for fixing and attaching the sensor holding portion to the sensor, and a jig connector locking portion for locking the jig connecting means received and inserted into the jig connector receiving portion of the formwork-side fixing jig, which is connected to the sensor holding portion so as to face the formwork-side fixing jig.

[0017] In addition, the above system may further include a formwork side fixing jig removal tool that assists in removing the formwork side fixing jig attached to the formwork from the formwork, and the formwork side fixing jig may have a stepped portion on one side where the formwork mounting portion comes into contact with the outer surface of the formwork, forming a gap that allows the formwork side fixing jig removal tool to be inserted.

[0018] In addition, in order to achieve the above-mentioned object, another aspect of the present invention is a moisture content measurement sensor installation tool for inside concrete, which is an instrument used to install an electrode-embedded sensor that measures the moisture content of concrete at a predetermined position inside the concrete, and is characterized in that it can assume two states: a first state before the concrete is poured, in which the sensor is attached to a formwork used for pouring the concrete while holding the sensor, and a second state after the concrete is poured, in which the sensor is removed from the formwork while remaining inside the concrete.

[0019] The sensor installation tool is composed of a formwork-side fixing jig attached to the formwork, a sensor-side fixing jig attached to the sensor, formwork fixing means for attaching the formwork-side fixing jig to the formwork, sensor fixing means for attaching the sensor-side fixing jig to the sensor, and jig connecting means for connecting the formwork-side fixing jig and the sensor-side fixing jig, and in the first state, the formwork-side fixing jig is attached to the formwork using the formwork fixing means, and the sensor-side fixing jig is attached to the sensor using the sensor fixing means and connected to the formwork-side fixing jig using the jig connecting means, and in the second state, the formwork-side fixing jig is removed from the formwork by releasing the formwork fixing means, and the sensor-side fixing jig is separated from the formwork-side fixing jig by releasing the jig connecting means and is left attached to the sensor in the concrete poured inside the formwork.

[0020] Furthermore, in the sensor installation tool, the formwork-side fixing jig comprises a cylindrical formwork insertion portion having a length equal to the length in the thickness direction of the formwork, an annular formwork mounting portion provided so as to expand on one end side of the formwork insertion portion and attached in contact with the outer surface of the formwork, a flat sensor-side jig mounting portion provided so as to close the other end side of the formwork insertion portion and enabling the sensor-side fixing jig to be attached on the inner surface side of the formwork, an opening provided to penetrate the sensor-side jig mounting portion and allowing the insertion of a connection portion through which the sensor is electrically connected to the measuring device main body, and a hole provided to penetrate the formwork mounting portion and receive the formwork fixing means. The sensor side fixing jig may have a formwork fixing device receiving portion and a jig connecting device receiving portion that receives the jig connecting means that is provided to pass through the sensor side jig mounting portion, and the sensor side fixing jig may have a sensor holding portion that is attached near the connection portion of the sensor, a sensor fixing device receiving portion that is provided to pass through the sensor holding portion and receives the sensor fixing device that fixes and attaches the sensor holding portion to the sensor, and a jig connecting device locking portion that locks the jig connecting means that is received and inserted into the jig fixing device receiving portion of the formwork side fixing jig that is connected to the sensor holding portion so as to face the formwork side fixing jig.

[0021] In addition, in the above sensor installation tool, the formwork side fixing jig may be provided with a step portion that forms a gap on one side where the formwork mounting portion comes into contact with the outer surface of the formwork.

[0022] Furthermore, in the above-mentioned sensor installation tool, the formwork side fixing jig may have an engaging convex portion that protrudes from one side where the sensor side fixing jig is attached at the sensor side jig attachment portion, and the sensor side fixing jig may have an engaging recess that allows the engaging convex portion to be inserted and is connected to the sensor holding portion so as to face the formwork side fixing jig side.

[0023] Furthermore, in the above-mentioned sensor installation tool, the sensor side fixing jig has a sensor holding portion with a U-shaped cross section that holds the sensor by clamping it from one side and the other side, and the jig connecting device locking portion is connected to a position on the sensor holding portion that is one side of the sensor, and the fitting recess is connected to a position on the sensor holding portion that is the other side of the sensor.

[0024] In addition, in order to achieve the above-mentioned object, another aspect of the present invention is a method for installing an electrode-embedded sensor that measures the moisture content of concrete at a predetermined position inside the concrete, comprising at least the steps of attaching a sensor installation tool that can be separated into two to the sensor, attaching the sensor installation tool with the sensor attached to a formwork before the concrete is poured, pouring concrete into the formwork, dividing the sensor installation tool into two, one on the formwork side and one on the inside of the concrete side, and releasing the sensor installation tool from the formwork, removing the formwork-side sensor installation tool from the formwork, and leaving the concrete-side sensor installation tool together with the sensor at a predetermined position inside the concrete.

[0025] Furthermore, in order to achieve the above object, another aspect of the present invention is a method for installing the sensor at a predetermined position inside the concrete using a tool comprising: a form-side fixing jig attached to a form used for pouring concrete; a sensor-side fixing jig attached to an electrode-embedded sensor that measures the moisture content of the concrete; form fixing means for attaching the form-side fixing jig to the form; sensor fixing means for attaching the sensor-side fixing jig to the sensor; and jig connecting means for connecting the form-side fixing jig and the sensor-side fixing jig, the method comprising the steps of: attaching the sensor-side fixing jig to the sensor using the sensor fixing means; a step of attaching the formwork-side fixing jig to the formwork using a fixing means for fixing the formwork-side fixing jig; a step of placing the sensor-side fixing jig with the sensor attached inside the formwork and connecting the sensor-side fixing jig to the formwork-side fixing jig using the jig connecting means; a step of pouring concrete into the formwork; a step of releasing the jig connecting means to separate the formwork-side fixing jig and the sensor-side fixing jig after pouring the concrete; and a step of releasing the formwork fixing means to remove the formwork-side fixing jig from the formwork and leaving the sensor-side fixing jig together with the sensor at a predetermined position inside the concrete. [Effects of the Invention]

[0026] According to the present invention, the sensor installation means can assume two states: a first state before concrete is poured, in which the sensor holds an electrode-embedded sensor that measures the moisture content of the concrete and is attached to a formwork used for pouring the concrete, and a second state after concrete is poured, in which the sensor is removed from the formwork with the sensor left inside the concrete. Therefore, by using this sensor installation means, the sensor can be easily installed in the formwork before the concrete is poured, and when the concrete is poured, the sensor can withstand the impact of the flowing concrete and remain in the designated position, and after the concrete is poured, the sensor and formwork can be easily separated, allowing the sensor to be left in the designated position. Therefore, by using a sensor left at a predetermined position inside the concrete, the moisture content of the concrete can be easily measured over a long period of time. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic diagram showing the configuration of a moisture content measurement sensor installation system for the inside of concrete according to the present invention. [Figure 2] 2 is a perspective view showing a formwork-side fixing jig that constitutes the moisture content measuring sensor installation tool used in the system shown in FIG. 1. FIG. [Figure 3] FIG. 3 is a front view of the formwork-side fixing jig shown in FIG. 2. [Figure 4] FIG. 3 is a rear view of the formwork-side fixing jig shown in FIG. 2. [Figure 5] FIG. 3 is a right side view of the formwork-side fixing jig shown in FIG. 2. [Figure 6] FIG. 6 is a cross-sectional view taken along line AA in FIG. 5. [Figure 7] 2 is a perspective view showing a sensor-side fixing jig that constitutes the moisture content measuring sensor installation tool used in the system shown in FIG. 1. FIG. [Figure 8] FIG. 8 is a front view of the sensor-side fixing jig shown in FIG. [Figure 9] FIG. 8 is a right side view of the sensor-side fixing jig shown in FIG. [Figure 10] FIG. 8 is a plan view of the sensor-side fixing jig shown in FIG. [Figure 11] 2 is a right side view showing a moisture content measuring sensor used in the system shown in FIG. 1. [Figure 12] 8 is a right side view illustrating the state in which the sensor-side fixing jig shown in FIG. 7 is attached to the moisture content measuring sensor. FIG. [Figure 13]8 is a schematic plan view illustrating a state in which the sensor-side fixing jig shown in FIG. 7 is fixed to the moisture content measuring sensor. FIG. [Figure 14] 8 is a perspective schematic view illustrating a state in which the sensor-side fixing jig shown in FIG. 7 is attached to a moisture content measuring sensor. FIG. [Figure 15] 3 is a right side view illustrating a state in which the formwork-side fixing jig shown in FIG. 2 is attached to the formwork. FIG. [Figure 16] 8 is a schematic right side view illustrating a state in which the sensor-side fixing jig shown in FIG. 7 is attached to the form-side fixing jig attached to the form. FIG. [Figure 17] 8 is a schematic right side view illustrating a state in which the sensor-side fixing jig shown in FIG. 7 is attached to the form-side fixing jig attached to the form. FIG. [Figure 18] FIG. 18 is a cross-sectional view taken along line BB in FIG. [Figure 19] 19 is a schematic cross-sectional view of the right side of FIG. 18 illustrating the state in which concrete has been poured into the formwork. [Figure 20] 10 is a front view showing a state in which a formwork-side fixing jig attached to the formwork is removed from the formwork after concrete has been poured. FIG. [Figure 21] 10 is a schematic right side view illustrating the state in which the formwork-side fixing jig attached to the formwork is removed from the formwork after concrete has been poured. FIG. [Figure 22] FIG. 10 is a perspective view showing a removal tool for a formwork-side fixing jig used when removing the formwork-side fixing jig from the formwork. [Figure 23] FIG. 23 is a side view of the formwork-side fixing jig removal tool shown in FIG. 22. [Figure 24] 23 is a plan view of the formwork-side fixing jig removal tool shown in FIG. 22. FIG. [Figure 25] This is a right side schematic view illustrating a moisture content measuring sensor in which the formwork-side fixing jig attached to the formwork has been removed from the formwork and left inside the concrete together with the sensor-side fixing jig. [Figure 26] FIG. 1 is a schematic diagram showing a method for measuring the moisture content inside concrete using a moisture content measuring sensor left inside the concrete. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. The present invention is directed to installing (leaving) an electrode-embedded sensor at a predetermined position inside a concrete structure to measure the moisture content of the concrete. In other words, the substrate electrode sensor proposed for embedding in concrete using the electrode-embedded electrical method is installed in formwork at a construction site or the like during the process of building a concrete structure, and can be embedded accurately and easily in a predetermined position inside the concrete. Then, the moisture content inside the structure can be measured using the measuring device over a long period of time in a simple manner.

[0029] The embodiments described below are preferred examples of the present invention and are therefore subject to various technical limitations. However, the scope of the present invention is not limited to these embodiments unless otherwise specified in the following description.

[0030] As shown in Fig. 1, the system for installing a moisture content measurement sensor inside concrete in this embodiment (hereinafter referred to as "this system") includes at least a moisture content measurement sensor installation tool (hereinafter simply referred to as "sensor installation tool") 1, a formwork 2, and a moisture content measurement sensor (hereinafter simply referred to as "sensor") 3. Here, the sensor installation tool 1 is an example of sensor installation means. Furthermore, this system may further include a formwork-side fixing jig removal tool 4.

[0031] The sensor installation device 1 can be in a first state before concrete is poured, in which it is attached to the formwork 2 while holding the sensor 3, and a second state after concrete is poured, in which it is removed from the formwork 2 while leaving the sensor 3 inside the concrete. In other words, the sensor installation tool 1 is an instrument used to install a sensor 3 at a predetermined position inside the concrete, and is attached to the formwork 2 so that the sensor 3 remains in the predetermined position inside the concrete when the concrete is poured, and can then be removed from the formwork 2.

[0032] This sensor installation tool 1 is composed of a separable formwork side fixing jig 10 and sensor side fixing jig 20, a formwork fixing tool 5 for attaching the formwork side fixing jig 10 to the formwork 2, a sensor fixing tool 25 for attaching the sensor side fixing jig 20 to the sensor 3, and a jig connecting tool 6 for connecting and separating the formwork side fixing jig 10 and the sensor side fixing jig 20.

[0033] In other words, when the sensor installation device 1 is in the first state described above, the formwork side fixing jig 10 is attached to the formwork 2 using the frame fixing device 5, and the sensor side fixing jig 20 is attached to the sensor 3 using the sensor fixing device 25, and is connected to the formwork side fixing jig 10 using the jig connecting device 6. Furthermore, when the sensor installation device 1 is in the second state described above, the formwork side fixing jig 10 is removed from the formwork 2 by releasing the formwork fixing device 5, and the sensor side fixing jig 20 is separated from the formwork side fixing jig 10 by releasing the jig connecting device 6, and is left attached to the sensor 3 inside the concrete poured inside the formwork 2.

[0034] 2 to 6, the form-side fixing jig 10 has a form fitting portion 11, a form mounting portion 12, a sensor-side jig mounting portion 13, an opening 14, a form-fixing-device receiving portion 15, and a jig-connecting-device receiving portion 16. The form-side fixing jig 10 may further have a fitting protrusion 17 and a step portion 18.

[0035] The form fitting part 11 is a cylindrical part having a length equal to the length in the thickness direction of the form 2, and when attached to the form 2, penetrates from one side of the form 2 to the other side. This form fitting part 11 is cylindrical and can be attached by fitting it into an installation hole 2a provided beforehand in the form 2, so that the form side fixing jig 10 can be easily attached to the form 2 and the form side fixing jig and the form can be attached in an appropriate position without misalignment. In the drawing, the form fitting portion 11 is shown as being cylindrical.

[0036] The formwork mounting portion 12 is a portion provided on one end side of the formwork insertion portion 11 so as to expand outward, and is annular in shape so as to be attached in contact with the outer surface of the formwork 2. This formwork mounting portion 12 is annular and eave-shaped, and therefore acts as a stopper when the formwork insertion portion 11 is inserted into the installation hole 2a provided in the formwork 2, preventing the formwork side fixing jig 10 from penetrating deeper into the formwork 2 than necessary. In the drawing, the formwork mounting portion 12 is shown as being ring-shaped.

[0037] The sensor side jig mounting portion 13 is a portion provided at the other end of the formwork insertion portion 11 to close the cylindrical interior, and is flat in shape to allow the sensor side fixing jig 20 to be mounted on the inner surface of the formwork 2. This sensor side jig mounting portion 13 is flat and blocks the cylindrical interior of the formwork insertion portion 11, making it possible to mount the sensor side fixing jig 20 on the inner surface of the formwork 2 while controlling the concrete poured inside the formwork 2 to prevent it from leaking out to the outside. In the drawing, the sensor side jig attachment portion 13 is shown as being disk-shaped.

[0038] Furthermore, the sensor-side jig mounting portion 13 is located on the inner surface of the formwork 2, allowing the sensor-side fixing jig 20 to be mounted thereon, so that when the formwork 2 is removed, the connection portion 32 of the sensor 3 does not protrude from the surface of the concrete, but is installed so that it is exposed within the cylindrical space in the concrete formed by the formwork insertion portion 11. Therefore, the aesthetic appearance of the concrete surface is not marred and the area around the connection portion 32 of the sensor 3 can be protected.

[0039] The opening 14 is a hole formed by penetrating the sensor-side jig attachment portion 13, and is adapted to allow the connection portion 32 of the sensor 3 to pass through. This opening 14 allows the connection part 32 of the sensor 3 to be exposed to the outside from the surface of the concrete, and allows for easy electrical connection between the contact part 51 of the measuring device main body 50 (described later) and the connection part 32 of the sensor 3. In the drawing, the opening 14 is shown as having a narrow, vertically elongated rectangular shape.

[0040] The formwork fixture receiving portion 15 is a hole formed through the formwork mounting portion 11 and is adapted to receive the formwork fixture 5 therein. Here, the form fixture 5 can be, for example, a tapping screw, which allows the form fixture 10 to be easily attached to and detached from the form 2. In the drawing, the formwork fixture receiving portion 15 is shown as a circular hole.

[0041] The jig connector receiving portion 16 is a hole formed through the sensor-side jig mounting portion 13 and is adapted to receive the jig connector 6 therein. Here, the jig connector 6 can be, for example, a tapping screw, which allows the formwork-side fixing jig 10 and the sensor-side fixing jig 20 to be easily connected and separated. In the drawing, the jig connector receiving portion 16 is shown as a circular hole.

[0042] The mating convex portion 17 is a protruding portion formed on the outer surface of the sensor side jig mounting portion 13 where the sensor side fixing jig 20 is attached, and assists in positioning the formwork side fixing jig 10 and the sensor side fixing jig 20 so that they do not shift from each other when connecting them.

[0043] The step portion 18 is a notch-like portion formed on one side (back side) where the formwork mounting portion 12 comes into contact with the outer surface of the formwork 2, and forms a gap that allows the formwork side fixing jig removal tool 4 to be inserted when the formwork side fixing jig 10 is removed from the formwork 2 using the formwork side fixing jig removal tool 4. In the figure, the step portion 18 is shown as being roughly C-shaped and formed on the back side of the ring-shaped formwork mounting portion 12, in the area excluding the formwork fixing device receiving portion 15 along the outer periphery of the cylindrical formwork insertion portion 11.

[0044] 7 to 10, the sensor-side fixing jig 20 has a sensor holding portion 21, a sensor fixing device receiving portion 22, and a jig connecting device locking portion 23. The sensor-side fixing jig 20 may further have a fitting recess 24.

[0045] The sensor holding portion 21 is attached near the connection portion 32 of the sensor 3 along one surface of the substrate 31 . This sensor holding portion 21 is attached along one surface of the substrate 31 to hold the sensor 3, and has a jig connector locking portion 23 that locks the jig connector 6 and a mating recess 24 that allows the mating protrusion 17 to be inserted, which are arranged adjacent to each other so as to face the formwork side fixed jig 10 side. In the figure, the sensor holding portion 21 is shown as having a downward U-shaped cross section, with a flat portion along one side of the substrate 31 of the sensor 3 connected at the upper end to a flat portion along the other side, and holding the sensor 3 by sandwiching it from both the one side and the other side.

[0046] The sensor fixture receiving portion 22 is a hole formed through the sensor holding portion 21 and is adapted to receive a sensor fixture 25 that fixes and attaches the sensor holding portion 21 to the sensor 3. In the drawing, the sensor fixture receiving portion 22 is shown as a circular hole.

[0047] Here, the sensor fixture 25 can be, for example, a push rivet, which enables the sensor holding portion 21 to be attached to the sensor 3. The sensor fixture 25 is preferably made of synthetic resin such as nylon, which has insulating properties and does not rust.

[0048] The jig connector locking portion 23 is a portion connected to the sensor holding portion 11 so as to face the formwork side fixed jig 10, and is configured to lock the jig connector 6 that has been received into and inserted into the jig connector receiving portion 16 on the formwork side fixed jig 10. That is, the inner surface of the jig connector locking portion 23 is provided with a thread groove that enables it to be threadedly engaged with the jig connector 6, which is, for example, a tapping screw. In the drawing, the jig connector locking portion 23 is shown as having a recess with an opening on one end side (the formwork-side fixing jig 10 side).

[0049] The mating recess 24 is a portion connected to the sensor holding portion 21 so as to face the formwork side fixed jig 10 side, and allows the mating protrusion 17 formed on the outer surface of the sensor side jig mounting portion 13 on the formwork side fixed jig 10 to be fitted in. This mating recess 24 cooperates with the mating protrusion 17 to assist in positioning the formwork side fixing jig 10 and the sensor side fixing jig 20 so that they do not shift position when they are connected, and by fitting the mating protrusion 17 into the mating recess 24, it becomes easier to join the formwork side fixing jig 10 and the sensor side fixing jig 20.

[0050] In this case, it is desirable that the sensor holding portion 21 has a U-shaped cross section, and that a jig connector locking portion 23 is connected to the sensor holding portion 21 at a position on one side of the substrate 31, and that a mating recess 24 is connected to the other side of the substrate 31, centered on the sensor holding portion 21. As a result, when connecting or disconnecting the formwork side fixing jig 10 and the sensor side fixing jig 20, even if the movement caused by the screwing of the jig connecting device 6 is transmitted to the sensor side fixing jig 20, the rotation of the sensor side fixing jig 20 is controlled by the mating convex portion 17 that fits into the mating recess 24, and the connection portion 32 is prevented from abutting against the opening 14 of the formwork side fixing jig 10 and applying a load.

[0051] In this way, when the sensor installation tool 1 is composed of a formwork side fixing jig 10 and a sensor side fixing jig 20 that can be connected and separated from each other, the sensor side fixing jig 20 that holds the sensor 3 can be connected to the formwork side fixing jig 10 before pouring the concrete, and the sensor 3 can be easily installed on the formwork 2 via the formwork side fixing jig 10 (and the sensor side fixing jig 20). On the other hand, after the concrete is poured, the sensor side fixing jig 20 is separated from the formwork side fixing jig 10, so that the sensor side fixing jig 20 can be reliably left in a predetermined position inside the concrete together with the sensor 3.

[0052] In this case, the sensor side fixing jig 20 is left inside the concrete and is used up once, but the formwork side fixing jig 10 can be removed from the formwork and used repeatedly, so it can be used efficiently without waste.

[0053] The formwork 2 is a component (framework) used for pouring concrete, and the material is not particularly limited as long as it can engage (screw) the formwork fixing device 5 that attaches the formwork side fixing jig 10 of the sensor installation device 1 to the formwork 2, and can be made of wood, metal, or synthetic resin. Although not shown, this formwork 2 is provided with an installation hole 2a in advance for attaching a formwork-side fixing jig 10, and the formwork insertion portion 11 can be inserted into the installation hole 2a.

[0054] The sensor 3 is a device for measuring the moisture content of concrete, and is an embedded type substrate electrode sensor that is embedded inside the concrete. As shown in FIG. 11, the sensor 3 is composed of, for example, a substrate 31, a connection portion 32 provided on one end 31a of the substrate 31, and an electrode portion 33 provided from the one end 31a of the substrate 31 toward the other end 31b.

[0055] The substrate 31 may be, for example, a multilayer substrate (four-layer structure) formed using epoxy resin, measuring 70 mm x 55 mm, and having a thickness of 3.2 mm to emphasize mechanical durability. The substrate 31 has copper foil inside as a shielding layer to prevent noise, and the surface except for the connection parts 32 and electrode parts 33 is coated with silicone resin for protection.

[0056] The connection part 32 is a data output electrode electrically connected to the contact part 51 of the measuring device main body 50, and is provided on one end 31a of the substrate 31, which is positioned facing the wall (surface) of the concrete structure. In FIG. 11, the connection portion 32 is shown as being provided above one end 31 a of the substrate 31 .

[0057] The electrode section 33 is made up of a transmitting electrode 34 and a receiving electrode 35, and is provided in a plurality of sets from one end 31a of the substrate 31 toward the other end 31b. Specifically, one set consists of two transmitting electrodes 34, 34 formed at a distance from each other in a direction along one end 31a of the substrate 31, and one receiving electrode 35 formed between these transmitting electrodes 34, 34, and multiple of these are mounted at any desired distance (depth) from the wall (surface) of the concrete structure.

[0058] The transmitter electrode 34 is an electrode part to which high frequency current is applied, and is made of a conductive metal exposed on one surface of the substrate 31, and is, for example, 8 mm x 5.5 mm in size and made of nickel plated with gold. The receiving electrode 35 is an electrode part that measures the high-frequency current passed by the transmitting electrode 34, and is made of a conductive metal exposed on one surface of the substrate 31. For example, it is 3 mm x 5.5 mm in size, and like the transmitting electrode 34, it is made of nickel plated with gold.

[0059] The measurement principle of the sensor 3 is high-frequency resistance. That is, a high-frequency current is passed from the transmitting electrode 34 of the sensor 3 to the concrete to be measured, the amplitude corresponding to the voltage difference with the receiving electrode 35 is measured, and this amplitude is converted into a device-specific count value corresponding to the electrical resistance.

[0060] In Figure 11, the transmitting electrodes 34 that make up the electrode section 33 are surrounded by a dashed line, and the receiving electrodes 35 are surrounded by a dashed double-dashed line, and are shown as a total of four sets formed along the direction from one end 31a of the substrate 31 to the other end 31b. The distance (depth) of the electrode unit 33 can be set at any position, for example, when the substrate electrode sensor 3 is buried inside the concrete, such that T1, which indicates the distance from the surface of the concrete to the center of the transmitter electrode 34 and the receiver electrode 35, is 5 mm, T2 is 15 mm, T3 is 30 mm, and T4 is 50 mm. Therefore, one end 31a of the substrate 31 is located on the surface of the concrete, and serves as a reference for setting the depth inside the concrete.

[0061] The substrate 31 is also provided with a sensor-side fixing jig locking hole 36 and a recessed cutout portion 37 . The sensor-side fixing jig locking hole 36 is a hole formed through the substrate 31 and serves to fix the sensor fixing tool 25 that attaches the sensor-side fixing jig 20 to the substrate 31 .

[0062] The concave cutout 37 is a cutout area formed to open toward one end 31a of the substrate 31, and is positioned and sized so that the part of the substrate 31 on which the connection portion 32 is formed can be inserted through the opening 14 provided in the formwork side fixing jig 10. In FIG. 11, the recessed cutout 37 is shown as being formed by cutting out the lower part in a U-shape so that the connecting portion 32 is provided above one end 31 a of the substrate 31 .

[0063] In this system, the sensor 3 can be left at a predetermined position inside the concrete using the sensor installation tool 1 described above. This procedure can be carried out, for example, as follows. First, as shown in Fig. 12, the sensor-side fixing jig 20 is attached to the sensor 3. That is, as shown by the outline arrow in Fig. 12, the connection portion 32 of the sensor 3 is not covered, and the jig connector locking portion 23 and the fitting recess 24 provided on the sensor-side fixing jig 20 are directed toward one surface 31a of the substrate 31, and the sensor-side fixing jig 20 is attached so as to sandwich the one surface side and the other surface side of the substrate 31. At this time, the positions of the sensor-side fixing jig locking hole 36 provided on the sensor 3 and the sensor fixture receiving portion 22 provided on the sensor-side fixing jig 20 are aligned.

[0064] Next, as shown in Fig. 13, the sensor-side fixing jig 20 is fixed to the sensor 3. That is, as shown by the outline arrow in Fig. 13, a sensor fixing jig 25 such as a nylon push rivet is attached so as to be inserted into the sensor fixing jig receiving portion 22 and the sensor-side fixing jig locking hole 36. In this way, as shown in FIG. 14, the sensor 3 can be prepared in which the sensor-side fixing jig 20 constituting the sensor installation tool 1 is attached with the connecting portion 32 exposed.

[0065] Next, as shown in Figure 15, the form-side fixing jig 10 is attached to the formwork 2. That is, the form-side fixing jig 10 is placed outside the formwork 2 before concrete is poured, and as shown by the outlined dotted arrow in Figure 15, the form-side fixing jig 10 is attached by inserting the form-side fixing jig 11 into the installation hole 2a that has been pre-made in the formwork 2. Thereafter, the formwork fixing jig 5 is inserted into the formwork fixing-tool receiving part 15, and the formwork-side fixing jig 10 is fixed and attached to the formwork 2.

[0066] Furthermore, as shown in Fig. 16, the sensor-side fixing jig 20 is connected to the formwork-side fixing jig 10. That is, the sensor-side fixing jig 20 with the sensor 3 attached thereto is placed inside the formwork 2, and while the sensor-side fixing jig 20 is brought closer to the formwork-side fixing jig 10 as shown by the outlined dotted arrow in Fig. 16, the connection portion 32 of the sensor 3 is inserted into the opening of the formwork-side fixing jig 10, and the fitting convex portion 17 of the formwork-side fixing jig 10 is fitted into the fitting concave portion 24 of the sensor-side fixing jig 20 to position it, as shown by the dotted arrow in Fig. 16. Then, the jig connector 6 is inserted into the jig connector receiving portion 16 to connect the formwork-side fixing jig 10 and the sensor-side fixing jig 20 together.

[0067] As a result, as shown in Figures 17 and 18, the formwork side fixing jig 10 and the sensor side fixing jig 20 are connected, and the sensor 3 is attached to the formwork 2 via the sensor installation device 1 (formwork side fixing jig 10 and sensor side fixing jig 20), and is easily placed at a predetermined position inside the formwork 2. That is, the sensor 3 is attached to the sensor side fixing jig 20 using a sensor fixing device 25, the sensor side fixing jig 20 is connected to the formwork side fixing jig 10 using a jig connecting device 6, and the formwork side fixing jig 10 is attached to the formwork 2 using a formwork fixing device 5.

[0068] Then, as shown in FIG. 19, concrete C is poured into the formwork 2. In this case, the sensor 3 is firmly attached to the formwork 2 by the sensor installation tool 1, so that it can withstand the impact of the flowing concrete when the concrete is poured and remain in the designated position.

[0069] Thereafter, when the poured concrete C has hardened, the form-side fixing jig 10 and the sensor-side fixing jig 20 are separated, and only the form-side fixing jig 10 is removed from the form 2, as shown in FIGS. That is, in the reverse of the above-described process of attaching the sensor installation tool 1 to the formwork 2, first the formwork-side fixing jig 10 and the sensor-side fixing jig 20 are separated by releasing (removing) the jig connecting tool 6. Next, the formwork fixing tool 5 is released to release the fixation of the formwork-side fixing jig 10 to the formwork 2. Then, the formwork-side fixing jig 10 is removed from the formwork 2.

[0070] At this time, the form-side fixing jig 10 can be removed from the form 2 efficiently by using a form-side fixing jig removal tool 4 shown in FIGS. This formwork side fixing jig removal tool 4 is an instrument that assists in removing the formwork side fixing jig 10 attached to the formwork 2 from the formwork 2, and has a shape that is bent in a ``L'' shape near the center of the length of the flat plate-shaped member.

[0071] In addition, the removal tool 4 for the formwork side fixed jig has, at one end in the longitudinal direction as the front end, an insertion section 41 whose shape matches the shape of the step section 18 formed on one surface (back surface) of the formwork mounting section 12 of the formwork side fixed jig 10, and at the other end in the longitudinal direction as the rear end, an operating section 42 that can be pushed down. In the drawing, the insertion portion 41 is shown as being arc-shaped (U-shaped) so as to fit the shape of the step portion 18 formed on the outer surface of the cylindrical form fitting portion 11.

[0072] As shown in Figure 21, the formwork side fixing jig removal tool 4 is used by inserting the insertion portion 41 at the tip into the step portion 18 of the formwork side fixing jig 10, and then pressing down the operating portion 42 at the rear end like a lever, as shown by the dotted arrow in Figure 21.

[0073] 25, the form-side fixing jig 10 that has been tightly attached to the form 2 can then be easily removed from the form 2. That is, as shown by the white arrow in Figure 25, the formwork side fixing jig 10 and the sensor side fixing jig 20 are separated, and only the formwork side fixing jig 10 is removed from the formwork 2, while the sensor side fixing jig 20 is left behind together with the sensor 3 in a predetermined, accurate position inside the concrete C.

[0074] Also, as shown by the black arrows in FIG. 25, the formwork 2 is removed from the outer surface of the concrete body. In this case, the connection part 32 of the sensor 3 is exposed to the outside of the concrete structure so that it can be easily accessed when measuring the moisture content, but it does not protrude from the wall surface, which ensures aesthetic appearance during actual use and protection of the connection part 32.

[0075] The moisture content inside the concrete C can be easily measured by connecting the tip of the contact part 51, which is electrically connected to the measuring device main body 50 by a cable, to the connection part 32 of the sensor 3 embedded in the concrete C, as shown in Figure 26. This makes it possible to easily measure the moisture content inside concrete over a long period of time. [Industrial Applicability]

[0076] The present invention can be used to easily leave sensors in a designated location inside concrete that measure moisture over a long period of time inside a structure after concrete has been poured, but it is also expected to be used to easily leave sensors in a designated location inside the object to be measured, such as soil, that measure moisture over a long period of time in various fields, such as detecting moisture in soil on agricultural land, detecting moisture in soil for growing grass in parks and golf courses, and detecting moisture in grains, pasture, and wood chips. [Explanation of symbols]

[0077] C. Concrete 1. Moisture content measurement sensor installation tool 2 Formwork 2a Installation hole 3. Moisture content measurement sensor (substrate electrode sensor) 4. Remover for formwork side fixing jig 5 Formwork Fixtures 6 Jig connector 10. Formwork side fixing jig 11 Formwork insertion part 12 Formwork mounting part 13 Sensor side jig mounting part 14 Openings 15 Formwork fixture receiving section 16 Jig connector receiving section 17. Fitting protrusion 18 Step 20 Sensor side fixing jig 21 Sensor holder 22 Sensor fixture receiving section 23 Jig connector locking portion 24 Fitting recess 25 Sensor fixture 31 PCB 32 Connection part (electrode part for data output) 33 Electrode part 34 Transmitting electrode 35 Receiving electrode 36 Sensor side fixing jig locking hole 37 Concave notch 41 Insertion section 42 Operation section 50 Measuring instrument body 51 Contact part

Claims

1. A formwork used for pouring concrete; an electrode-embedded sensor for measuring the moisture content of the concrete; a sensor installation means used to install the sensor at a predetermined position inside the concrete; Equipped with The sensor installation means a first state before concrete is poured, in which the sensor is attached to the formwork while being held; a second state after concrete is poured, in which the formwork is removed with the sensor left inside the concrete; and A moisture content measurement sensor installation system for concrete.

2. The sensor installation means A formwork-side fixing jig attached to the formwork; a sensor-side fixing jig attached to the sensor; a form fixing means for attaching the form-side fixing jig to the form; a sensor fixing means for attaching the sensor-side fixing jig to the sensor; a jig connecting means for connecting the formwork-side fixing jig and the sensor-side fixing jig; It consists of In the first state, The formwork-side fixing jig is attached to the formwork using the formwork fixing means, the sensor-side fixing jig is attached to the sensor using the sensor fixing means and is connected to the formwork-side fixing jig using the jig connecting means, In the second state, The formwork-side fixing jig is removed from the formwork by releasing the formwork fixing means, The sensor-side fixing jig is separated from the formwork-side fixing jig by releasing the jig connecting means, and is left attached to the sensor inside the concrete poured inside the formwork.

2. The moisture content measurement sensor installation system for inside concrete according to claim 1.

3. The formwork side fixing jig is a cylindrical form fitting portion having a length equal to the length in the thickness direction of the form; a ring-shaped form fitting portion provided so as to expand on one end side of the form fitting portion and attached in contact with the outer surface of the form; a flat-plate-shaped sensor-side jig attachment portion provided so as to close the other end of the form fitting portion, which allows the sensor-side fixing jig to be attached to the inner surface side of the form; an opening provided through the sensor-side jig attachment portion, through which a connection portion for electrically connecting the sensor to a measuring device main body can be inserted; a form fixture receiving portion provided through the form mounting portion and configured to receive the form fixing means; a jig connector receiving portion that is provided to penetrate the sensor-side jig mounting portion and that receives the jig connector; and The sensor-side fixing jig is a sensor holder attached to the sensor near the connection portion; a sensor fixture receiving portion provided to penetrate the sensor holding portion and configured to receive a sensor fixing means for fixing and attaching the sensor holding portion to the sensor; a jig connector locking portion connected to the sensor holding portion so as to face the formwork-side fixing jig, and configured to lock the jig connecting means received and inserted into the jig connector receiving portion of the formwork-side fixing jig; 3. The moisture content measurement sensor installation system for inside concrete according to claim 2.

4. Further provided is a formwork side fixing jig removal tool that assists in removing the formwork side fixing jig attached to the formwork from the formwork, The formwork-side fixing jig has a step portion on one surface side where the formwork mounting portion comes into contact with the outer surface of the formwork, which forms a gap through which the formwork-side fixing jig removal tool can be inserted.

4. The moisture content measurement sensor installation system for inside concrete according to claim 3.

5. An instrument used to install an electrode-embedded sensor at a predetermined position inside concrete to measure the moisture content of the concrete, a first state before concrete is poured, in which the sensor is held and attached to a formwork used for pouring concrete; a second state after the concrete is poured, in which the formwork is removed with the sensor left inside the concrete; and A moisture content measurement sensor installation tool for installing a moisture content measurement sensor inside concrete.

6. A formwork-side fixing jig attached to the formwork; a sensor-side fixing jig attached to the sensor; a form fixing means for attaching the form-side fixing jig to the form; a sensor fixing means for attaching the sensor-side fixing jig to the sensor; a jig connecting means for connecting the formwork-side fixing jig and the sensor-side fixing jig; It consists of In the first state, The formwork-side fixing jig is attached to the formwork using the formwork fixing means, the sensor-side fixing jig is attached to the sensor using the sensor fixing means and is connected to the formwork-side fixing jig using the jig connecting means, In the second state, The formwork-side fixing jig is removed from the formwork by releasing the formwork fixing means, The sensor-side fixing jig is separated from the formwork-side fixing jig by releasing the jig connecting means, and is left attached to the sensor inside the concrete poured inside the formwork.

6. The moisture content measuring sensor installation tool for installing a moisture content measuring sensor inside concrete according to claim 5.

7. The formwork side fixing jig is a cylindrical form fitting portion having a length equal to the length in the thickness direction of the form; a ring-shaped form fitting portion provided so as to expand on one end side of the form fitting portion and attached in contact with the outer surface of the form; a flat-plate-shaped sensor-side jig attachment portion provided so as to close the other end of the form fitting portion, which allows the sensor-side fixing jig to be attached to the inner surface side of the form; an opening provided through the sensor-side jig attachment portion, through which a connection portion for electrically connecting the sensor to a measuring device main body can be inserted; a form fixture receiving portion provided through the form mounting portion and configured to receive the form fixing means; a jig connector receiving portion that is provided to penetrate the sensor-side jig mounting portion and that receives the jig connector; and The sensor-side fixing jig is a sensor holder attached to the sensor near the connection portion; a sensor fixture receiving portion provided to penetrate the sensor holding portion and configured to receive a sensor fixing means for fixing and attaching the sensor holding portion to the sensor; a jig connector locking portion connected to the sensor holding portion so as to face the formwork-side fixing jig, and configured to lock the jig connector received and inserted into the jig fixing device receiving portion of the formwork-side fixing jig; 7. The moisture content measurement sensor installation tool for installing a moisture content measurement sensor inside concrete according to claim 6.

8. The formwork-side fixing jig has a step portion that forms a gap on one side where the formwork mounting portion comes into contact with the outer surface of the formwork.

8. The moisture content measurement sensor installation tool for installing a moisture content measurement sensor inside concrete according to claim 7.

9. The formwork side fixing jig is The sensor-side jig mounting portion has a fitting protrusion protruding from one surface to which the sensor-side fixing jig is mounted, The sensor-side fixing jig is a fitting recess that is connected to the sensor holding portion so as to face the formwork-side fixing jig and that allows the fitting protrusion to be fitted therein; 8. The moisture content measurement sensor installation tool for installing a moisture content measurement sensor inside concrete according to claim 7.

10. The sensor-side fixing jig has a sensor holding portion having a U-shaped cross section that holds the sensor by sandwiching it from one side and the other side, and the jig connecting device locking portion is connected to a position on the one side of the sensor in the sensor holding portion, and the fitting recess is connected to a position on the other side of the sensor in the sensor holding portion. The moisture content measurement sensor installation tool for installing a moisture content measurement sensor inside concrete according to claim 9.

11. A method for installing an electrode-embedded sensor at a predetermined position inside concrete to measure the moisture content of the concrete, comprising: a step of attaching a sensor installation tool that can be separated into two pieces to the sensor; a step of attaching the sensor installation tool to which the sensor is attached to a formwork before concrete is poured; Pouring concrete into the formwork; After pouring the concrete, dividing the sensor installation tool into two parts, one on the formwork side and one on the inside of the concrete; a step of releasing the sensor installation tool from the formwork, removing the formwork-side sensor installation tool from the formwork, and leaving the concrete interior-side sensor installation tool together with the sensor at a predetermined position inside the concrete; At least A method for installing a moisture content measurement sensor inside concrete.

12. A formwork-side fixing jig attached to a formwork used for pouring concrete; a sensor-side fixing jig attached to an electrode-embedded sensor for measuring the moisture content of the concrete; a form fixing means for attaching the form-side fixing jig to the form; a sensor fixing means for attaching the sensor-side fixing jig to the sensor; a jig connecting means for connecting the formwork-side fixing jig and the sensor-side fixing jig; A method for installing the sensor at a predetermined position inside the concrete using an instrument comprising: a step of attaching the sensor-side fixing jig to the sensor using the sensor fixing means; a step of placing the formwork-side fixing jig outside the formwork before concrete is poured, and attaching the formwork-side fixing jig to the formwork using the formwork fixing means; a step of placing the sensor-side fixing jig with the sensor attached inside the formwork, and connecting the sensor-side fixing jig to the formwork-side fixing jig using the jig connecting means; Pouring concrete into the formwork; a step of releasing the jig connecting means to separate the formwork-side fixing jig and the sensor-side fixing jig after the concrete has been poured; a step of releasing the form fixing means, removing the form fixing jig from the form, and leaving the sensor fixing jig together with the sensor at a predetermined position inside the concrete; At least A method for installing a moisture content measurement sensor inside concrete.

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