Non-contact height measurement method and device using electrostatic capacitance

Abstract

To provide a non-contact height measurement method and device using electrostatic capacitance, which can easily arrange a pair of electrode bodies in close contact in a straight line on the outer side of a non-metallic formwork without any unevenness in the vertical direction, and which prevents the influence of metal reinforcing members, etc. on electrolysis, thereby enabling accurate height measurement. [Solution] A non-contact height measurement method in which a pair of strip-shaped electrode bodies 2 connected to conductive wires 21 are arranged horizontally spaced apart along the vertical direction on the outer surface of a non-metallic formwork 1, and the introduction height of a cement-based material 5 introduced into a space formed inside the non-metallic formwork is measured based on the electrostatic capacitance obtained by inputting an AC signal into the pair of electrode bodies.The non-metallic formwork comprises a base 10 made of a non-metallic material, a plurality of vertical reinforcements arranged at predetermined intervals on the outer surface of the base, and a plurality of horizontal reinforcements arranged at predetermined intervals on the outer surface of the base and intersecting the vertical reinforcements, and an opening 101 is formed on the outer surface of the base in at least one of the areas formed between adjacent vertical reinforcements, including a smooth surface 100 where no horizontal reinforcements are arranged from the upper end to the lower end of the base.

Description

[Technical Field]

[0001] The present invention relates to a non-contact height measurement method and device using electrostatic capacitance, and more particularly to a non-contact height measurement method and device that detects the height level of a cement-based material on the opposite side of a wall based on the value of electrostatic capacitance between electrodes. [Background technology]

[0002] Various height measurement methods have been developed to measure the amount of concrete or other cementitious material filled into a formwork (for example, Patent Document 1). Most of these methods involve a sensor being brought into direct contact with the concrete to detect the amount, but these methods have had problems such as the need to set up a sensor at each pouring point and the fact that the sensor is buried inside the structure and cannot be reused.

[0003] To solve this problem, the inventor has succeeded in developing a technology for non-contact measurement of the concrete pouring height within a formwork by applying a high-frequency current to a sensor installed on the outer surface of the formwork to generate an electric field, and utilizing the principle that the electric field changes depending on the concrete pouring height and the capacitance increases (Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-3222 [Patent Document 2] Patent No. 7636611 Summary of the Invention [Problem to be solved by the invention]

[0005] The non-contact height measurement method using capacitance in Patent Document 2 is an excellent technology in that it can easily detect the height level of cement-based materials inside a formwork made of a non-metallic material using a simple, inexpensive sensor placed outside the formwork, without requiring a circuit to process complex electrical signals, and is particularly capable of detecting relatively high height levels.

[0006] In addition, in this technology, the placement of the sensor on the formwork involves placing a pair of electrode bodies connected to conductive wires in close contact or at a distance from each other in the vertical direction on the outer side of the formwork, and it is assumed that the sensor will be placed on the outer surface of the flat formwork.

[0007] On the other hand, for example, at concrete pouring sites in tunnel construction, the outer surface of the formwork may not be flat, or there may not be enough space to place the sensor. Also, when metal reinforcing members are used in the formwork, these metal reinforcing members may affect the generated electric field, making it difficult to accurately measure the capacitance. In these respects, there is room for improvement.

[0008] The present invention has been made in consideration of the above circumstances, and aims to provide a non-contact height measurement method using electrostatic capacitance, and a measuring device to be used therewith, which, in construction work in which a cementitious substance is introduced into a space formed using a non-metallic formwork, allows a pair of electrode bodies to be easily arranged in close contact in a straight line on the outer side of the non-metallic formwork without any unevenness in the vertical direction, prevents the influence of metal reinforcing members, etc. on electrolysis, and enables accurate height measurement in the process. [Means for solving the problem]

[0009] The non-contact height measurement method using capacitance of the present invention has been made to solve the above technical problems, and has the following features.

[0010] [1] A non-contact height measurement method in which a pair of strip-shaped electrodes connected to conductors are arranged at intervals in the horizontal direction along the vertical direction on the outer surface of a non-metallic formwork, and an introduction height of a cement-based material introduced into a space formed inside the non-metallic formwork is measured based on the electrostatic capacitance obtained by inputting an AC signal to the pair of electrodes, The non-metallic formwork is a substrate made of a non-metallic material; a plurality of longitudinal reinforcements arranged at predetermined intervals on the outer surface of the base body; a plurality of horizontal reinforcements disposed at predetermined intervals on the outer surface of the base body and intersecting the vertical reinforcements; Equipped with an opening is formed in the outer surface of the base in at least one of the regions formed between adjacent vertical reinforcements, the opening including a smooth surface where no horizontal reinforcement is disposed from the upper end side to the lower end side of the base, In the opening, the pair of electrode bodies are arranged in close contact with the smooth surface in a straight line without any undulations in the vertical direction, and a separation portion is formed between both outer ends of the pair of electrode bodies in the width direction and the vertical reinforcement member adjacent to the electrode bodies, for suppressing a change in the intensity of the electric field of the pair of electrode bodies. A non-contact height measurement method using capacitance. [2] The longitudinal reinforcement or transverse reinforcement is made of a non-metallic material or a metallic material. [1] Non-contact height measurement method using capacitance. [3] The vertical reinforcement is made of a non-metallic material, and the horizontal distance between the outer ends of the pair of electrode bodies in the width direction and the vertical reinforcement adjacent to the electrode bodies is 15 mm or more. [1] or [2] Non-contact height measurement method using capacitance. [4] The vertical reinforcement is made of a metal material, and the horizontal distance between the outer ends of the pair of electrode bodies in the width direction and the vertical reinforcement adjacent to the electrode bodies is 40 mm or more. [1] or [2] Non-contact height measurement method using capacitance. [5] The surfaces of the pair of electrodes are covered with an insulator, and the insulator is covered with a shielding sheet. [1] to [4] are non-contact height measurement methods using capacitance. [6] When connecting multiple non-metallic formworks in the vertical direction, Lower ends of the pair of electrode bodies installed in the upper non-metallic formwork are connected to upper ends of the pair of electrode bodies installed in the lower non-metallic formwork by a connector. [1] to [5] are non-contact height measurement methods using capacitance. [7] The connector is covered with a shield tube. [6] Non-contact height measurement method using capacitance. [8] Of the non-metallic formworks adjacent to each other in the vertical direction, the non-metallic formwork located on the upper side has the horizontal reinforcement member made of a metal material at its lower end, and the non-metallic formwork located on the lower side has the horizontal reinforcement member made of a metal material at its upper end, The connector is connected across the surfaces of the horizontal reinforcement at the lower end of the non-metallic formwork located above and the horizontal reinforcement at the upper end of the non-metallic formwork located below. Non-contact height measurement method using capacitance [6] or [7]. [9] Of the non-metallic formworks adjacent to each other in the vertical direction, the non-metallic formwork located on the upper side has the horizontal reinforcement material made of a metal material at its lower end, and the non-metallic formwork located on the lower side has the horizontal reinforcement material made of a metal material at its upper end, The lateral reinforcement material made of the metal material of the connector portion is removed, and the pair of electrode bodies are closely arranged in a straight line without any undulations in the vertical direction. Non-contact height measurement method using capacitance [6] or [7].

[10] The non-metallic formwork is connected to another formwork on which the pair of electrode bodies is not installed. [1] to [9] are non-contact height measurement methods using capacitance.

[11] As the AC signal, a measurement AC signal of an arbitrary measurement frequency is input, and the impedance and phase angle between the pair of electrodes are measured to calculate the capacitive reactance, and the value of the electrostatic capacitance is measured, and based on the value, the introduction height of the cement-based material to be poured into the space is calculated. [1] to

[10] Non-contact height measurement method using capacitance.

[12] The measurement frequency is 1 KHz to 20 MHz, and the measurement AC signal is in the range of 5 mVrms to 5 Vrms.

[11] non-contact height measurement method using capacitance.

[13] The initial value of the capacitance during measurement is set as zero. [1] to

[12] are non-contact height measurement methods using capacitance.

[14] The pair of electrode bodies are long electrode bodies, and a part of the electrode body in the longitudinal direction is formed wide. [1] to

[13] are non-contact height measurement methods using capacitance.

[15] The pair of electrode bodies is waterproofed. [1] to

[14] Non-contact height measurement method using capacitance.

[16] At least one of a numerical value or a graph of the introduction height of the cement-based material poured into the space is displayed by a display device. [1] to

[15] are non-contact height measurement methods using capacitance.

[17] The base of the non-metallic formwork is an FRP formwork made of FRP, [1] to

[16] are non-contact height measurement methods using capacitance.

[18] A non-contact height measurement device used in the non-contact height measurement method by capacitance according to [1], Non-metallic formwork; a pair of strip-shaped electrode bodies connected to conductors and arranged side by side with a gap in the horizontal direction; Equipped with The non-metallic formwork is a substrate made of a non-metallic material; a plurality of longitudinal reinforcements arranged at predetermined intervals on the outer surface of the base body; a plurality of horizontal reinforcements disposed at predetermined intervals on the outer surface of the base body and intersecting the vertical reinforcements; Equipped with an opening is formed in the outer surface of the base in at least one of the regions formed between adjacent vertical reinforcements, the opening including a smooth surface where no horizontal reinforcement is disposed from the upper end side to the lower end side of the base, In the opening, the pair of electrode bodies are arranged in close contact with the smooth surface in a straight line without any undulations in the vertical direction, and a separation portion is formed between both outer ends of the pair of electrode bodies in the width direction and the vertical reinforcement member adjacent to the electrode bodies, for suppressing a change in the intensity of the electric field of the pair of electrode bodies. Non-contact height measurement device. [Effects of the Invention]

[0011] According to the non-contact height measurement method and measuring device using capacitance of the present invention, a pair of electrode bodies connected to conductive wires can be easily arranged in a straight line in close contact with each other in the vertical direction of the outer part of the non-metallic formwork without any unevenness, and the influence of metal reinforcing members, etc. on electrolysis can be prevented, allowing accurate height measurement. [Brief explanation of the drawings]

[0012] [Figure 1] 1A and 1B show an embodiment of a non-metallic formwork of a measuring device used in a non-contact height measurement method using capacitance according to the present invention, in which (a) is a schematic front view showing an embodiment in which a pair of electrode bodies are arranged on a smooth surface on which no lateral reinforcement is provided of a non-metallic formwork having lateral reinforcement and vertical reinforcement made of a non-metallic material, (b) is an AA cross-sectional view of (a), and (c) is a BB cross-sectional view of (a). [Figure 2] 1 shows another embodiment of a non-metallic formwork of a measuring device used in a non-contact height measurement method using capacitance according to the present invention, in which (a) is a schematic front view showing an embodiment in which a pair of electrode bodies are arranged on a smooth surface on which some of the vertical reinforcements and horizontal reinforcements of a non-metallic formwork having horizontal reinforcements and vertical reinforcements made of non-metallic material are not provided, (b) is an AA cross-sectional view in (a), and (c) is a BB cross-sectional view in (a). [Figure 3] 1 shows another embodiment of a non-metallic formwork of a measuring device used in a non-contact height measurement method using capacitance according to the present invention, in which (a) is a schematic front view of a pair of electrode bodies arranged in a non-metallic formwork having vertical reinforcement members made of a metal material and horizontal reinforcement members made of a non-metallic material and a metal material, (b) is an AA cross-sectional view in (a), and (c) is a BB cross-sectional view in (a). [Figure 4]10 is a graph showing the change in capacitance measurement value with the distance between a pair of electrode bodies and a reinforcing steel member. [Figure 5] This shows an embodiment in which an upper formwork and a lower formwork are joined, where (a) is a front view of an embodiment in which a pair of electrode bodies are connected to each other by a connector at the connection part of the non-metallic formwork, (b) is an AA cross-sectional view of (a), and (c) is an enlarged side cross-sectional view of the connection part in (a). [Figure 6] (a) is a cross-sectional view of a center using an FRP formwork for tunnel lining, (b) is an enlarged front view of an embodiment showing the hinge portion in (a) where a metal material is used as a horizontal reinforcement at the connection portion of the electrode body, (c) is an enlarged side cross-sectional view of the connection portion between the upper formwork and the lower formwork in (b), and (d) is an enlarged side cross-sectional view showing the hinge of the connection portion in (c) in an open state. [Figure 7] (a) is an enlarged front view of a center tunnel using FRP formwork for tunnel lining, where the electrode body connection uses FRP transverse reinforcement, (b) is an enlarged cross-sectional view of the connection between the upper and lower formwork in (a), and (c) is an enlarged side view of the connection in (b) with the hinge open. [Figure 8] This is a perspective view of an FRP measurement formwork with an electrode body attached to the center. [Figure 9] FIG. 9 is an explanatory diagram showing the concrete pouring height in FIG. 8 displayed on a monitor screen. [Figure 10] FIG. 10 is a perspective view showing an embodiment in which a sensor-equipped FRP height measurement formwork, to which an electrode body is attached and integrated, is connected to another formwork. [Figure 11] FIG. 11 is an explanatory diagram showing the concrete pouring height in FIG. 10 displayed on a monitor screen. [Figure 12] (a) is a front view showing an embodiment in which a pair of electrode bodies is arranged, consisting of a long electrode body and an electrode body with an electrode whose width is increased at a predetermined position, and (b) is a graph showing the relationship between concrete height and capacitance in (a). [Figure 13] FIG. 10 is a top view showing an embodiment in which a pair of electrode bodies are waterproofed. DETAILED DESCRIPTION OF THE INVENTION

[0013] The non-contact height measurement method using capacitance of the present invention is a non-contact height measurement method in which a pair of strip-shaped electrode bodies to which conductors are connected are arranged horizontally spaced apart along the vertical direction on the outer surface of a non-metallic formwork, and the introduction height of a cementitious material introduced into a space formed inside the non-metallic formwork is measured based on the capacitance obtained by inputting an AC signal into the pair of electrode bodies.The non-metallic formwork uses a base made of a non-metallic material, a plurality of vertical reinforcements arranged at predetermined intervals on the outer surface of the base, and a plurality of horizontal reinforcements arranged at predetermined intervals on the outer surface of the base and intersecting the vertical reinforcements, and in at least one of the areas formed between adjacent vertical reinforcements on the outer surface of the base, an opening is formed including a smooth surface where no horizontal reinforcements are arranged from the upper end to the lower end of the base.

[0014] An embodiment of a non-contact height measurement method and a measurement device using capacitance according to the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an embodiment of a non-metallic formwork of a measurement device used in a non-contact height measurement method using capacitance according to the present invention. (a) is a schematic front view of a non-metallic formwork having horizontal and vertical reinforcements made of a non-metallic material, in which a pair of electrode bodies are arranged on a smooth surface where no horizontal reinforcements are provided. (b) is an AA cross-sectional view of (a), and (c) is a BB cross-sectional view of (a). FIG. 2 shows another embodiment of a non-metallic formwork of a measurement device. (a) is a schematic front view of a non-metallic formwork having horizontal and vertical reinforcements made of a non-metallic material, in which a pair of electrode bodies are arranged on a smooth surface where no vertical reinforcements or part of the horizontal reinforcements are provided. (b) is an AA cross-sectional view of (a), and (c) is a BB cross-sectional view of (a). It should be noted that the present invention is not limited to this embodiment.

[0015] First, the non-contact height measurement method using capacitance of the present invention will be described in detail. The measurement method of the present invention uses a measurement device that uses the non-metallic formwork of the above configuration in which a pair of electrodes connected to conductors are arranged at a distance, and measures the introduction height of a cementitious material introduced into a space based on the capacitance obtained by inputting an AC signal to the electrodes. The operating principle of the method is that by applying an AC current between a pair of electrodes that are separated by a distance and insulated by air, an electric field is generated between the electrodes, generating capacitance like a capacitor, and when a cementitious material with a higher dielectric constant than air is introduced into this electric field, the capacitance increases.

[0016] The cement-based material is not particularly limited as long as it has a high and measurable relative dielectric constant, and specific examples include cement-based materials such as fresh concrete and fresh mortar.

[0017] The input signal to the pair of electrodes is a measurement AC signal of a predetermined frequency, and the impedance and phase angle between the electrodes are measured to calculate the capacitive reactance.The capacitance value is then calculated using the following equation, and the height level of the cement-based material is determined from this value. X C =1 / (2πfC) (X C : capacitive reactance f: frequency of AC voltage C: electrostatic capacitance The measurement AC signal is preferably in the range of 5 mVrms to 5 Vrms, and the measurement frequency is preferably in the range of 1 kHz to 20 MHz. By setting the measurement frequency in a high frequency range, the detection sensitivity to electric field fluctuations is improved, allowing for the detection of minute changes in capacitance, and the device is relatively resistant to noise, suppressing the effects of external interference and electromagnetic noise.

[0018] As a capacitance measuring device, an LCR meter, a multimeter, an impedance analyzer, or other device capable of generating and applying an AC input signal and measuring capacitance can be suitably used. Regarding the thickness of the non-metallic formwork, since it becomes more difficult to detect capacitance as the thickness increases, it is necessary to set the thickness within a detectable range. Furthermore, the measurement data measured by the measuring device can be displayed on a display device. Furthermore, the capacitance at the start of measurement can be measured as an initial value of zero, taking into account the capacitance value due to the surrounding environment when the electrode body is installed.

[0019] A pair of electrodes connected to conductive wires are closely spaced apart and disposed on the outer periphery of the non-metallic formwork. When the cementitious material is filled into the space formed by the non-metallic formwork, the capacitance between the electrodes increases as the filling height increases. This allows the height of the cementitious material to be measured based on the capacitance value.

[0020] The electrode body may be a conductive metal plate, and lightweight thin plate or film-like electrodes made of copper, aluminum, or other materials are particularly suitable. The electrode body can be attached to the non-metallic formwork by, for example, using double-sided tape or an insulating adhesive on the outer surface of the non-metallic formwork, or by using conductive copper foil adhesive tape or conductive aluminum foil adhesive tape coated with adhesive on one side of the electrode body. It is desirable to protect the outer surface of the electrode body by covering it with insulating single-sided adhesive tape, for example.

[0021] Alternatively, a pair of electrode bodies can be formed on an insulator in advance. Specifically, for example, two plate- or film-shaped electrode bodies can be disposed at a distance from each other on one side of a film made of an insulating material, or two film-shaped electrode bodies can be disposed at a distance from each other between two films made of an insulating material, thereby forming a pair of electrode bodies integrally. Furthermore, the non-metallic mold can be made of a composite material as long as the surface that comes into contact with the electrode bodies is a non-metallic mold. Furthermore, the film-shaped electrode body can be formed on a film by printing, vapor deposition, or plating.

[0022] The conductor may be a lead wire or a coaxial cable, and the lead wire may be a solid wire or a twisted wire. However, when a lead wire is used, since the higher the frequency, the more susceptible it is to the influence of external electromagnetic waves, it is preferable to use a coaxial cable, which is used as a cable for transmitting high-frequency signals and is less susceptible to the influence of electromagnetic waves, when the transmission length is long.

[0023] For example, when non-metallic formwork is used for pouring concrete in tunnel construction, the formwork must have sufficient strength, and to provide this strength, a base body, a plurality of vertical reinforcements arranged at predetermined intervals on the outer surface of the base body, and a plurality of horizontal reinforcements arranged at predetermined intervals on the outer surface of the base body and intersecting the vertical reinforcements are provided. On the other hand, to accurately measure the capacitance, the electrode body needs to be closely and linearly arranged on the flat outer surface without any undulations in the vertical direction. However, in the case of non-metallic formwork with vertical reinforcements and horizontal reinforcements on the outer surface for reinforcement as described above, the horizontal reinforcements in particular get in the way, making it impossible to closely and linearly arrange the electrode body without any undulations in the vertical direction. Therefore, in the present invention, as illustrated in Figures 1 and 2, a non-metallic formwork 1 is used in which an opening 101 including a smooth surface 100 where no horizontal reinforcement 13 is arranged from the upper end to the lower end of the base 10 is formed in at least one of the areas formed between adjacent vertical reinforcement 11 on the outer surface of the base 10 made of a non-metallic material, and an electrode body 2 is arranged on the smooth surface 100.

[0024] In the embodiment shown in FIGS. 1 and 2, the non-metallic formwork 1 is an FRP formwork in which the main material of the base 10 is FRP (fiber-reinforced plastic), and the vertical reinforcement members 11 and horizontal reinforcement members 13 are also made of FRP. Furthermore, in the non-metallic formwork 1 of the embodiment shown in FIG. 1, an opening 101 including a smooth surface 100 is provided where the horizontal reinforcement members 13 are not arranged vertically between the two vertical reinforcement members 11. Furthermore, in the non-metallic formwork 1 of the embodiment shown in FIG. 2, the central vertical reinforcement member and the horizontal reinforcement members 13 between the two vertical reinforcement members 11 are not arranged vertically, and an opening 101 including a smooth surface 100 is provided, and a pair of electrode bodies 2 connected to conductive wires 21 are arranged vertically at a distance in the space. In the non-metallic formwork 1 of the embodiment shown in FIGS. 1 and 2, the outer surface where the reinforcement members are not arranged is a flat, smooth surface 100, allowing the electrode bodies 2 to be closely arranged in a straight line without any vertical undulations.

[0025] The material of the base 10 in the non-metallic formwork 1 used in the present invention is not particularly limited as long as it is an insulator, and in addition to the FRP of the above embodiment, organic materials such as plastic, rubber, wood, leather, etc., inorganic materials such as fine ceramics, glass, porcelain, refractories, cement-based substances, etc., or composite materials thereof can be used. Note that the non-metallic formwork in the present invention means a formwork in which the main material of the base 10 is a non-metallic substance, and formworks that partially use metallic auxiliary members are also included in the non-metallic formwork of the present invention.

[0026] Furthermore, the materials of the vertical reinforcement members 11 and horizontal reinforcement members 13 provided on the outer surface of the non-metallic formwork 1 may be the same non-metallic material as the material of the non-metallic formwork 1, or may be metals such as iron, aluminum, stainless steel, or materials containing these metals. Furthermore, the vertical reinforcement members 11 and horizontal reinforcement members 13 may be formed integrally with the non-metallic formwork 1 or formed separately and fixed thereto, and there are no limitations on the shape, etc., as long as sufficient reinforcing strength is obtained, and reinforcement materials such as solid wood, hollow tubes, and ribbed shapes can be used.

[0027] 1 and 2, when the materials of the vertical reinforcement members 11 and the horizontal reinforcement members 13 are non-metallic, it is desirable to ensure that the separation (α) between the pair of electrode bodies 2 and the adjacent vertical reinforcement members 11, i.e., the horizontal distance (α) from both outer ends of the pair of electrode bodies 2 in the width direction to the vertical reinforcement member 11, is 15 mm or more. By making the separation (α) 15 mm or more, it is possible to ensure sufficient space for arranging the electrode bodies 2 and also to suppress the effect of changes in the strength of the generated electric field.

[0028] On the other hand, if there are vertical reinforcement members 12 or horizontal reinforcement members 14 made of metal material near a pair of electrode bodies 2, they will affect the change in strength of the electric field generated by applying an alternating current to the electrode bodies 2, compared to when all reinforcement members are made of non-metallic materials, and it is expected that this will cause a change in capacitance and make height detection unstable.

[0029] Therefore, an experiment was conducted to investigate the influence of metal reinforcement materials using an FRP formwork 1 of the embodiment shown in Figure 3. In the FRP formwork 1 of the embodiment shown in Figure 3, the vertical reinforcement materials 12 are made of metal, and the horizontal reinforcement materials are horizontal reinforcement materials 13, 14 that are a mixture of FRP and metal. In addition, an opening 101 including a smooth surface 100 where the horizontal reinforcement materials 13, 14 are not arranged vertically between the two vertical reinforcement materials 12 is secured, and the distance between the two vertical reinforcement materials 12 made of metal is made adjustable.

[0030] (experiment) In air, the change in capacitance was measured by varying the distance (separation) between the outer ends of a pair of electrode bodies in the width direction of the FRP formwork 1 shown in Figure 3 and the adjacent variable longitudinal reinforcement members 12 made of a metal material from 10 mm to 50 mm in 10 mm increments. 40 mm copper foil tape was used as the electrode body 2, with the tape spacing set to 2 mm. A measurement AC signal was applied at 0.63 Vrms and a measurement frequency of 100 kHz, and the capacitance was read using an LCR meter. The capacitance readings were adjusted by subtracting the initial capacitance of 268.9 pF at spacings of 40 mm and 50 mm, where no influence of the metal material was observed, from the capacitance at each spacing from 10 mm to 50 mm. The results are shown in Table 1 and the graph in Figure 4.

[0031] [Table 1]

[0032] 4, it was confirmed that there is no effect of reinforcing materials made of metal when the separation between the vertical reinforcement 12 and the electrode body 2 is 40 mm or more. Therefore, when at least one of the vertical reinforcement 12 or the horizontal reinforcement 14 is made of a metal material or a material containing a metal material, it is desirable that the separation (β) between the pair of electrode bodies 2 and the adjacent vertical reinforcement 12, i.e., the horizontal distance (β) from both outer ends of the electrode body 2 in the width direction to the vertical reinforcement 12, be 40 mm or more.

[0033] In the non-contact height measurement method using electrostatic capacitance of the present invention, multiple non-metallic formworks 1 can be connected vertically. Specifically, the configuration of the embodiment shown in FIG. 5 can be exemplified. In the configuration shown in FIG. 5, the upper and lower electrode bodies 2 are connected to each other by connectors 22 at the connection points of the upper and lower FRP formworks 1 (15), (16). Furthermore, as a measure to prevent high-frequency noise from the external environment that may be transmitted to the electrode bodies 2, conductors 21, and connectors 22 due to the application of high frequency, a shielding sheet 24 is attached to the outer surface of the pair of electrode bodies 2 with an insulator 23 sandwiched therebetween. Furthermore, the conductors 21 and connectors 22 are covered with a shielding tube for drip-proofing. The shielding sheet may also be connected to an earth rod or the like for earthing.

[0034] For example, if the height of one FRP formwork 1 is 1.8 m, and concrete is to be poured higher than that, the upper formwork 15 and the lower formwork 16 are connected to raise the formwork and pour concrete. At this time, to measure the pouring height, the upper and lower electrode bodies 2 are connected at the formwork joint. The electrode bodies 2, which are arranged along the top and bottom of the outer surfaces of the upper formwork 15 and the lower formwork 16, are connected using connectors 22 at the cross reinforcement 13 where the upper formwork 15 and the lower formwork 16 are connected. As shown in FIG. 5(c), the electrode body 2 is connected to the vertical reinforcement 11 at the cross reinforcement 13, via a conductor 21 attached along the outer surface spanning the upper formwork 15 and the lower formwork 16, via the connector 22. In this way, the pouring height can be continuously measured even at the formwork joint. In measuring the height, since the electrode body 2 does not extend beyond the thickness of the horizontal reinforcement 13 at the connection between the upper formwork 15 and the lower formwork 16, when the pouring portion is moved from the lower formwork 16 to the upper formwork 15, the thickness of the horizontal reinforcement 13 is taken into consideration when adding to the height value at the part of the conductor 21 where the electrode body 2 is not connected, in order to increase and adjust the height of the connection part of the electrode body 2.

[0035] Furthermore, when connecting non-metallic formwork 1 above and below, if the horizontal reinforcement 13 at the lower end of the upper formwork 15 and the horizontal reinforcement 14 at the upper end of the lower formwork 16 are made of a metal material, it is preferable that the connector 22 connecting the lower end of the electrode body 2 installed in the upper formwork 15 and the upper end of the electrode body 2 installed in the lower formwork 16 is connected across the surface of the horizontal reinforcement 14. It is also possible to remove the horizontal reinforcement 14 at the connection portion and arrange the electrode body 2 closely in a straight line with no undulations in the vertical direction.

[0036] Specifically, an embodiment shown in FIG. 6 can be illustrated. FIG. 6(a) is a cross-sectional view of a center 61 using an FRP formwork 1 for tunnel lining. Two hinges 17 are provided on each side of the FRP formwork 1, one for connecting the upper and lower FRP formworks 1 and for setting and contracting the center 61. The hinges 17 are provided to change the angle of the FRP formwork 1, expand and set the center 61 when pouring concrete, and then contract and slide the center 61 to the next position after pouring the concrete. FIG. 6(b) is an enlarged front view of the hinge 17 in FIG. 6(a), and the horizontal reinforcement 14 connected by the hinge 17 is made of steel. FIG. 6(c) is an enlarged side cross-sectional view of FIG. 6(b). The connector 22 connects the conductor 21 across the horizontal reinforcement 14 at the connection between the upper formwork 15 and the lower formwork 16. The connection method is the same as in the embodiment shown in FIG. 5. FIG. 6(d) is an enlarged side cross-sectional view of the connection portion in FIG. 6(c) with the hinge open.

[0037] The embodiment shown in Fig. 7(a) shows a case where the connection of the electrode body in the center 61 in Fig. 6(a) uses FRP horizontal reinforcement 13. Fig. 7(b) is an enlarged cross-sectional view of the connection between the upper and lower formwork in Fig. 7(a). Fig. 7(c) is an enlarged side view of the connection in Fig. 7(b) with hinge 17 open.

[0038] 8 is a perspective view showing an embodiment of the measuring device of the present invention in which an electrode body 2 is attached to a center 61. The electrode body 2 is attached to the left and right inside of the center 61 along the circumferential direction, and the conductor 21 extending from the lower end of the center 61 is connected to a measuring device 3 and a display device 4 for measurement and display. Here, a pair of electrode bodies 2 are attached to the inside of the center 61 at three locations, top and bottom, left and right, on the existing side, center, and gable side, for measurement. The electrode body 2 is attached to the center 61 in close contact with the inner surface of the center 61, and the connection parts of the FRP formwork 1 and the hinges 17 are connected with connectors 22.

[0039] Figure 9 is an explanatory diagram showing the concrete pouring height of tunnel 6 of the measuring device in Figure 8 displayed on monitor 4. The upper image in Figure 9 is a view of tunnel 6 from the side, and the lower image is a cross-sectional view of tunnel 6 from the front. By displaying and illustrating the height of poured concrete in this way, the pouring status can be visually grasped in real time. In this case, since the cross-sectional shape of tunnel 6 is arch-shaped, the relationship between the length of electrode body 2 and the concrete pouring height is calculated in advance to match the arch shape, and the pouring height is then calculated.

[0040] The non-metallic formwork 1 of the present invention can also be connected to another formwork 18 that does not have a pair of electrode bodies 2 installed. Examples of the other formwork 18 that does not have the electrode bodies 2 installed include wooden formwork, transparent formwork, and plastic formwork, and these can be used in appropriate combinations. It is also preferable to prevent misalignment of the joints between the non-metallic formwork 1 and the other formwork 18. Specifically, for example, a single pipe can be fastened with a Home Tie (registered trademark). For more secure fastening, fastening holes can be provided at the connection between the non-metallic formwork 1 and the other formwork 18, and the non-metallic formwork 1 and the other formwork 18 can be fastened with bolts or clamps. To further enhance the waterproofing of the joints, waterproof tape can be applied to the joints between the non-metallic formwork 1 and the other formwork 18, or a seal can be sandwiched between the joints. In this case, it is preferable to apply a waterproof sealant to the frame portion of the non-metallic formwork 1 in advance.

[0041] FIG. 10 is a schematic perspective view showing an embodiment in which the FRP formwork 1, with electrode bodies 2 attached vertically to the outside of each side of the FRP formwork 1, is connected between other forms 18 (wooden formwork). Note that in the embodiment shown in FIG. 10, the vertical reinforcement members 11 and horizontal reinforcement members 13 of the FRP formwork 1 are omitted. In this embodiment, even when detecting the pouring height at multiple locations over a large pouring area, it is possible to simultaneously grasp the pouring height of the areas close to the FRP formwork 1. Furthermore, in cases where pouring is performed by switching valves using piping rather than by moving the boom of a ready-mixed concrete pump truck, the pouring height of the concrete at the pouring location can be known, allowing the timing of each valve switch to be grasped in a timely manner. Furthermore, data can be transmitted via a wireless communication device and displayed on a display device 4, such as a personal computer. The transmission destination may be within the pouring site or to a remote office, etc.

[0042] Figure 11 is an explanatory diagram of an embodiment in which the concrete pouring height in Figure 10 is displayed on a monitor screen. In this embodiment, the pouring height at each of four positions is displayed. By displaying this display on a large screen in the work site, those involved in the work can keep track of the progress of the concrete pouring, which can be helpful in preparing for the next job, etc.

[0043] FIG. 12(a) is a front view of another embodiment, showing a case where a pair of electrode bodies 2 is arranged, with a long electrode body 2 and a wide electrode body 25 with a wider width at a predetermined position, to measure height. In this embodiment, the wide electrode body 25 is arranged in a fixed height section at the center of the side of the FRP formwork 1, so that the gradient of increase in capacitance becomes larger when the poured concrete reaches the position of the wide electrode body 25. This allows for more accurate measurement by detecting when the concrete has been filled up to a certain height of the wide electrode body 25 and correcting the actual height. The long electrode body 2 has a width of 20 mm, and the short, wide electrode body 25 at the middle has a width of 80 mm and a length of 20 mm, and is attached at a height of 50 cm to 52 cm. This method can also be applied to pouring concrete when the proportionality constant changes due to the hardening of the poured concrete over a long period of time.

[0044] Figure 12(b) is a graph showing the relationship between the height of poured concrete and the capacitance in Figure 12(a). The measurement results show a constant rate of increase from 0 cm to approximately 50 cm in height, then a sudden increase from 50 cm to 52 cm, where the wide electrode 25 is installed, before returning to the previous rate at approximately 52 cm, past the wide electrode 25. This change in rate of increase from 50 to 52 cm confirms that concrete has been poured up to the height where the wide electrode 25 is installed. From that point on, the height can be continuously measured based on the proportionality constant. Note that the wide electrode 25 can be installed in multiple locations as needed.

[0045] FIG. 13 is a plan view showing an embodiment in which a pair of electrode bodies 2 is waterproofed. The capacitance of the pair of electrode bodies 2 increases when a dielectric substance such as water is present in the electric field outside the FRP formwork 1, potentially resulting in an error in the height value. Therefore, it is preferable to cover the periphery of the electrode body 2 with a waterproof barrier 26. The waterproof barrier 26 is positioned at a certain distance from the electrode body 2, providing an air layer, which serves as an insulator, between them. The waterproof barrier 26 also serves to prevent contact with other dielectric substances. Alternatively, instead of the waterproof barrier 26, it is also possible to attach a plate such as an acrylic plate directly to the copper sheet. In this case, double-sided tape or adhesive is preferably used for attachment. Furthermore, the waterproof effect can be further enhanced by sandwiching an insulator 23 between the pair of electrode bodies 2 and attaching a shielding sheet 24 to the outer surface, or by combining this with covering the conductors 21 and / or connectors 22 with a shielding tube.

[0046] The measuring device of the present invention is a non-contact height measuring device used in the non-contact height measuring method using electrostatic capacitance, and comprises a non-metallic formwork 1 and a pair of strip-shaped electrodes 1 connected to conductive wires 21 and arranged side by side at a horizontal interval from each other. The non-metallic formwork 1 comprises a base 10 made of a non-metallic material, a plurality of vertical reinforcements 11, 12 arranged at predetermined intervals on the outer surface of the base 10, and a plurality of horizontal reinforcements 13, 14 arranged at predetermined intervals on the outer surface of the base and intersecting the vertical reinforcements 11, 12. The outer surface of the base 10 is provided with adjacent In at least one of the regions formed between the vertical reinforcements 11, 12, an opening 101 is formed, including a smooth surface 100 on which no horizontal reinforcements 13, 14 are arranged from the upper end to the lower end of the base 10, and in the opening 101, a pair of electrode bodies 1 are closely arranged in a straight line on the smooth surface 100 without any unevenness in the vertical direction, and a separation portion (α) or (β) is formed between the outer ends of the pair of electrode bodies 2 in the width direction and the vertical reinforcements 11, 12 adjacent to this electrode body 2, which suppresses changes in the strength of the electric field of the pair of electrode bodies 2.

[0047] According to the non-contact height measuring device of the present invention having the above-described configuration, a pair of electrode bodies 2 connected to the conductive wires 21 can be easily arranged in a straight line in close contact with each other in the vertical direction of the outer part of the non-metallic formwork 1 without any unevenness, and the influence of metal reinforcing members, etc. on electrolysis can be prevented, allowing accurate height measurement. [Explanation of symbols]

[0048] 1. Non-metallic formwork (FRP formwork) 10 Base 100 Smooth surface 101 Opening 11 Non-metallic longitudinal reinforcement 12 Metal longitudinal reinforcement 13 Non-metallic lateral reinforcement 14 Metal horizontal reinforcement 15 Upper formwork 16 Lower formwork 17 Hinge 18 Other Formwork 19 Connection between non-metallic formwork (FRP formwork with sensors) and other formwork (wooden formwork) α Separation part β Separation part 2 Electrode body 21 Conductor 22 Connectors 23 Insulators 24 Shield Sheet 25 Wide electrode body 26 Waterproof enclosure 3. Measuring equipment 4. Display device (monitor) 5. Cementitious materials 6. Tunnel 61 Center 62 Pouring space

Claims

1. A non-contact height measurement method comprising: arranging a pair of strip-shaped electrodes connected to conductors at a horizontal interval along the vertical direction on the outer surface of a non-metallic formwork; and measuring the introduction height of a cementitious material introduced into a space formed inside the non-metallic formwork based on the electrostatic capacitance obtained by inputting an AC signal to the pair of electrodes; The non-metallic formwork is a substrate made of a non-metallic material; a plurality of longitudinal reinforcements arranged at predetermined intervals on the outer surface of the base body; a plurality of horizontal reinforcements disposed at predetermined intervals on the outer surface of the base body and intersecting the vertical reinforcements; Equipped with an opening is formed in the outer surface of the base in at least one of the regions formed between adjacent vertical reinforcements, the opening including a smooth surface where no horizontal reinforcement is disposed from the upper end side to the lower end side of the base, In the opening, the pair of electrode bodies are closely arranged on the smooth surface in a straight line without any undulations in the vertical direction, and a separation portion is formed between both outer ends of the pair of electrode bodies in the width direction and the vertical reinforcement member adjacent to the electrode bodies, for suppressing a change in the strength of the electric field of the pair of electrode bodies. A non-contact height measurement method using capacitance.

2. The longitudinal reinforcement or transverse reinforcement is made of a non-metallic material or a metallic material.

2. The non-contact height measurement method using capacitance according to claim 1.

3. the longitudinal reinforcement members are made of a non-metallic material, and the horizontal distance between the outer ends of the pair of electrode bodies in the width direction and the longitudinal reinforcement members adjacent to the electrode bodies is 15 mm or more; 3. The non-contact height measurement method using capacitance according to claim 2.

4. the longitudinal reinforcement members are made of a metal material, and the horizontal distance between the outer ends of the pair of electrode bodies in the width direction and the longitudinal reinforcement members adjacent to the electrode bodies is 40 mm or more; 3. The non-contact height measurement method using capacitance according to claim 2.

5. The surfaces of the pair of electrodes are covered with an insulator, and the insulator is covered with a shielding sheet.

2. The non-contact height measurement method using capacitance according to claim 1.

6. When connecting multiple non-metallic formworks in the vertical direction, Lower ends of the pair of electrode bodies installed in the upper non-metallic formwork are connected to upper ends of the pair of electrode bodies installed in the lower non-metallic formwork by a connector.

2. The non-contact height measurement method using capacitance according to claim 1.

7. The connector is covered with a shield tube.

7. The non-contact height measurement method using capacitance according to claim 6.

8. Of the non-metallic formworks adjacent to each other in the vertical direction, the non-metallic formwork located on the upper side has the horizontal reinforcement member made of a metal material at its lower end, and the non-metallic formwork located on the lower side has the horizontal reinforcement member made of a metal material at its upper end, The connector is connected across the surfaces of the horizontal reinforcement at the lower end of the non-metallic formwork located above and the horizontal reinforcement at the upper end of the non-metallic formwork located below.

7. The non-contact height measurement method using capacitance according to claim 6.

9. Of the non-metallic formworks adjacent to each other in the vertical direction, the non-metallic formwork located on the upper side has the horizontal reinforcement member made of a metal material at its lower end, and the non-metallic formwork located on the lower side has the horizontal reinforcement member made of a metal material at its upper end, The lateral reinforcement material made of the metal material of the connector portion is removed, and the pair of electrode bodies are closely arranged in a straight line without any undulations in the vertical direction.

7. The non-contact height measurement method using capacitance according to claim 6.

10. The non-metallic form is connected to another form on which the pair of electrode bodies is not installed.

2. The non-contact capacitance height measurement method of claim 1.

11. a measuring AC signal of an arbitrary measurement frequency is input as the AC signal, the impedance and phase angle between the pair of electrodes are measured to calculate the capacitive reactance, the value of the electrostatic capacitance is measured, and the introduction height of the cement-based material to be poured into the space is calculated based on the value; 2. The non-contact height measurement method using capacitance according to claim 1.

12. The measurement frequency is in the range of 1 KHz to 20 MHz, and the measurement AC signal is in the range of 5 mVrms to 5 Vrms. The method for non-contact height measurement using capacitance according to claim 11.

13. The initial capacitance value at the time of measurement is set as zero.

2. The non-contact height measurement method using capacitance according to claim 1.

14. The pair of electrode bodies are long electrode bodies, and a part of the electrode bodies in the longitudinal direction is formed to be wider.

2. The non-contact height measurement method using capacitance according to claim 1.

15. The pair of electrode bodies is waterproofed.

2. The non-contact height measurement method using capacitance according to claim 1.

16. At least one of a numerical value or a graph of the introduction height of the cement-based material poured into the space is displayed on a display device.

2. The non-contact height measurement method using capacitance according to claim 1.

17. The base of the non-metallic formwork is an FRP formwork made of FRP.

2. The non-contact height measurement method using capacitance according to claim 1.

18. A non-contact height measurement device used in the non-contact height measurement method using capacitance according to claim 1, Non-metallic formwork; a pair of strip-shaped electrode bodies connected to conductors and arranged side by side with a gap in the horizontal direction; Equipped with The non-metallic formwork is a substrate made of a non-metallic material; a plurality of longitudinal reinforcements arranged at predetermined intervals on the outer surface of the base body; a plurality of horizontal reinforcements disposed at predetermined intervals on the outer surface of the base body and intersecting the vertical reinforcements; Equipped with an opening is formed in the outer surface of the base in at least one of the regions formed between adjacent vertical reinforcements, the opening including a smooth surface where no horizontal reinforcement is disposed from the upper end side to the lower end side of the base, In the opening, the pair of electrode bodies are closely arranged on the smooth surface in a straight line without any undulations in the vertical direction, and a separation portion is formed between both outer ends of the pair of electrode bodies in the width direction and the vertical reinforcement member adjacent to the electrode bodies, for suppressing a change in the strength of the electric field of the pair of electrode bodies. Non-contact height measurement device.

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