Air Permeability Measuring Device, Air Permeability Measuring Method, and Air Permeability Measuring System

Abstract

To provide an air permeance measurement device which can rapidly evaluate the air permeance of concrete, for example.SOLUTION: An air permeance measurement device (10) includes: an attachment (11) with an opening unit (11b); a cylinder (13) with an inside space (13a) leading to the opening unit (11b); a piston (14) for changing the volume of the inside space (13a); a pressure sensor (16) for detecting the pressure of the inside space (13a); and a first control unit (17). The first control unit (17) calculates the air permeance rate and specifies the air inflow amount corresponding to the air permeance rate.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a breathability measurement device, a breathability measurement method, and a breathability measurement system.

Background Art

[0002] Patent Document 1 describes a breathability measurement method using a simple air permeability test device or the like that can measure the mass transfer resistance of the surface layer of a porous material.

[0003] Non-Patent Document 1 describes a single-chamber method in which the inside of a chamber attached to the concrete surface is depressurized, and then the time required for the air pressure inside the chamber to return to atmospheric pressure is measured to obtain a breathability index.

[0004] Non-Patent Document 2 describes a method in which a desiccator lid is closely attached to the concrete surface and the inside is depressurized, and then the time for the degree of vacuum to decrease due to the inflow of air from the concrete surface is measured to calculate the air suction rate.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Non-Patent Documents

[0006]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] One aspect of the present disclosure aims to provide a gas permeability measuring device, a gas permeability measuring method, and a gas permeability measuring system capable of evaluating the gas permeability of concrete or the like in a short time.

Means for Solving the Problems

[0008] In order to solve the above problems, a gas permeability measuring device according to one aspect of the present disclosure includes an attachment that is disposed on the surface of an object to be measured and has an opening facing the object to be measured, a cylinder that has an internal space communicating with the opening of the attachment and is fixed to the attachment, a piston that changes the volume of the internal space by sliding on the inner peripheral surface of the cylinder, a pressure sensor that detects the pressure of the internal space through the opening of the attachment, and a control unit. The control unit calculates the pressure difference between a first pressure, which is the pressure of the internal space at a certain time after reducing the pressure by applying a tensile force to the piston in a state where the attachment is in close contact with the surface of the object to be measured, and a second pressure, which is the pressure of the internal space after a predetermined measurement time has elapsed since the first pressure was detected, and calculates a gas permeability rate, which is an index for evaluating the gas permeability of the object to be measured, by dividing the pressure difference by the measurement time. The control unit specifies the air inflow amount corresponding to the gas permeability rate by referring to the correlation between the calculated gas permeability rate and the air inflow amount, which is the amount of air flowing into the internal space when the internal space is depressurized.

Effects of the Invention

[0009] According to one aspect of the present disclosure, the gas permeability of concrete or the like can be evaluated in a short time.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0011] 〔Embodiment 1〕 Hereinafter, the air permeability measuring device 10 and the air permeability measuring system 100 in Embodiment 1 of the present disclosure will be described with reference to FIGS. 1 to 8. FIG. 1 is a block diagram showing the configuration of the air permeability measuring system 100. FIG. 2 is a diagram showing the overall configuration of the air permeability measuring device 10.

[0012] As shown in FIG. 1, the air permeability measuring system 100 includes an air permeability measuring device 10 and a communication device 20 that can communicate with the air permeability measuring device 10. The air permeability measuring device 10 is for measuring the air permeability of the surface layer of the measurement object.

[0013] Examples of the measurement object include concrete. However, the measurement object is not limited to concrete and may be mortar, cement paste, etc.

[0014] Here, air permeability is a property indicating the ease of air penetration through the object to be measured. The air permeability is affected by the moisture content of the object to be measured, and the higher the moisture content, the lower the air permeability. By measuring the air permeability of the object to be measured, it is possible to evaluate the quality such as the denseness of the surface layer of the object to be measured.

[0015] As shown in FIG. 2, the air permeability measuring device 10 includes an attachment 11, a gasket 12, a cylinder 13, a piston 14, a stopper 15, a pressure sensor 16, and a control device 101. As shown in FIG. 1, the control device 101 has a first control unit 17, a storage unit 18, and a communication unit 19.

[0016] The attachment 11 is made of, for example, metal and is a member for arranging the cylinder 13. The attachment 11 is disposed in close contact with the surface of the object to be measured via the gasket 12.

[0017] As shown in FIG. 2, the attachment 11 has a contact portion 11a, an opening portion 11b, a cylindrical portion 11c, a mounting portion 11d, and a communication hole 11e. The contact portion 11a is made of, for example, a circular plate-like member. The contact portion 11a contacts the surface of the object to be measured via the gasket 12.

[0018] The opening portion 11b is formed on the central side of the contact portion 11a and has, for example, a circular outer shape. When measuring the air permeability of the object to be measured by the air permeability measuring device 10, the opening portion 11b is disposed to face the object to be measured. Further, in a state where the cylinder 13 is fixed to the attachment 11, the opening portion 11b is configured to communicate with the connection hole 13b of the cylinder 13.

[0019] The cylindrical portion 11c is provided so as to protrude from the contact portion 11a on the side opposite to the object to be measured. The cylinder 13 is disposed in the cylindrical portion 11c. The outer peripheral surface of the cylinder 13 fits on the inner peripheral surface of the cylindrical portion 11c.

[0020] Further, a mounting portion 11d is formed on a part of the outer peripheral surface of the cylindrical portion 11c. The mounting portion 11d has, for example, a triangular prism shape. The pressure sensor 16 and the control device 101 are attached to the mounting portion 11d by screws or the like. Note that the shape of the mounting portion 11d and the location where the mounting portion 11d is disposed can be changed as appropriate.

[0021] The mounting portion 11d is provided with a communication hole 11e that communicates with the opening 11b of the attachment 11. The pressure sensor 16 is connected to the communication hole 11e and communicates with the internal space 13a of the cylinder 13 through the opening 11b and the connection hole 13b.

[0022] The gasket 12 is made of, for example, low-hardness silicon and is configured to adhere to the surface of the object to be measured. The gasket 12 is disposed between the surface of the object to be measured and the attachment 11 so as to surround the periphery of the opening 11b of the attachment 11, and seals the space between the surface of the object to be measured and the opening 11b of the attachment 11.

[0023] Note that the material of the gasket 12 may be any material that can ensure sealing performance. In addition to low-hardness silicon, a gel-like member or the like may be used. Further, when the attachment 11 itself is configured to be able to adhere well to the surface of the object to be measured, the gasket 12 may not be provided.

[0024] The cylinder 13 is, for example, a cylindrical container. The cylinder 13 has an internal space 13a and a connection hole 13b. The internal space 13a communicates with the opening 11b of the attachment 11 through the connection hole 13b. The cylinder 13 is made of, for example, a transparent container and is configured such that the user can visually recognize the state inside the cylinder 13. A plurality of scales (not shown) are engraved on the outer peripheral surface of the cylinder 13.

[0025] The piston 14 has a piston rod 141, a piston head 142, an engaging convex portion 143, and a handle 144. The piston rod 141 is a rod-shaped member and is disposed so as to be reciprocally movable along the longitudinal direction of the cylinder 13 (the vertical direction in FIG. 2).

[0026] A piston head 142 is provided at the end of the piston rod 141 on the attachment 11 side. The piston head 142 is, for example, a cylindrical member made of rubber. The piston head 142 is fitted inside the cylinder 13.

[0027] The piston head 142 is disposed so as to be slidably movable along the longitudinal direction of the cylinder 13 on the inner peripheral surface 130 of the cylinder 13. When the piston head 142 slides on the inner peripheral surface 130 of the cylinder 13, the volume of the internal space 13a of the cylinder 13 changes.

[0028] An engaging convex portion 143 is provided on the piston head 142 side of the piston rod 141. The engaging convex portion 143 protrudes on both sides in the radial direction of the cylinder 13 (the left-right direction in FIG. 2). The engaging convex portion 143 engages with an engaging portion 15b of a stopper 15 described later.

[0029] A handle 144 is provided at the end of the piston rod 141 opposite to the piston head 142. The handle 144 is a member for the user of the air permeability measuring device 10 to grip and move the piston 14 when operating the piston 14.

[0030] A stopper 15 is provided at the end of the cylinder 13 opposite to the attachment 11. The stopper 15 is a member for regulating the operation of the piston 14. The stopper 15 has a hole portion 15a and an engaging portion 15b.

[0031] The hole portion 15a is a hole for passing through the piston rod 141 and the engaging convex portion 143. The engaging portion 15b engages with the engaging convex portion 143 that has passed through the hole portion 15a. When the engaging convex portion 143 engages with the engaging portion 15b, the position of the piston head 142 in the longitudinal direction of the cylinder 13 is restricted, and the piston 14 can be maintained in a stopped state.

[0032] The pressure sensor 16 is, for example, a digital pressure gauge. The pressure sensor 16 can detect a pressure in the range of, for example, -100 to 100 [kPa]. The pressure sensor 16 has a display unit 16a. The pressure value detected by the pressure sensor 16 is displayed on the display unit 16a.

[0033] The pressure sensor 16 is attached to the attachment portion 11d of the attachment 11 and connected to the communication hole 11e. The pressure sensor 16 detects the pressure in the internal space 13a of the cylinder 13 via the communication hole 11e and the opening 11b. The pressure sensor 16 displays the detected pressure value of the internal space 13a on the display unit 16a. Further, the pressure sensor 16 outputs a signal corresponding to the detected pressure value of the internal space 13a to the first control unit 17 (see FIG. 1).

[0034] As shown in FIG. 1, the first control unit 17 of the control device 101 controls the air permeability measuring device 10. The first control unit 17 is an example of a control unit. The first control unit 17 is composed of a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), etc.

[0035] The first control unit 17 calculates the air permeability rate and specifies the air inflow amount corresponding to the calculated air permeability rate. Here, the air permeability rate is an index for evaluating the air permeability of the measurement object. The air inflow amount is the amount of air that flows into the internal space 13a of the cylinder 13 from the measurement object due to a pressure difference when the internal space 13a of the cylinder 13 is depressurized with the attachment 11 in close contact with the surface of the measurement object.

[0036] Further, the first control unit 17 determines the presence or absence of air leakage in the attachment 11. The first control unit 17 transmits information regarding the air permeation rate, the air inflow rate, and the presence or absence of air leakage, etc., to the transmission / reception unit 23 of the communication device 20 via the communication unit 19.

[0037] The storage unit 18 is an auxiliary storage device such as a hard disk drive, for example. In the storage unit 18, data regarding the correlation between the air permeation rate and the air inflow rate, for example, is stored.

[0038] The communication unit 19 communicates with the transmission / reception unit 23 of the communication device 20. As the communication method between the communication unit 19 and the transmission / reception unit 23, for example, Bluetooth (registered trademark) can be used. In addition, as the above communication method, Wi-Fi (registered trademark) or the like may also be used.

[0039] The communication unit 19 transmits data for causing the communication device 20 to display information regarding the pressure in the internal space 13a of the cylinder 13 detected by the pressure sensor 16, the air permeation rate calculated by the first control unit 17, and the air inflow rate specified by the first control unit 17.

[0040] The communication device 20 is a portable terminal such as a smartphone, for example, and is a device capable of communicating with the air permeability measurement device 10. It is assumed that the user installs an application dedicated to pressure measurement in the communication device 20 in advance. Note that the communication device 20 is not limited to a portable terminal, and may be a personal computer, a tablet terminal, or the like.

[0041] The communication device 20 includes a second control unit 21, a second display unit 22, and a transmission / reception unit 23. The second control unit 21 is composed of a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), etc. The second control unit 21 is an example of a control unit. The second display unit 22 displays the information transmitted from the communication unit 19 of the air permeability measurement device 10.

[0042] For example, on the second display unit 22, information regarding the air permeability calculated by the first control unit 17, information regarding the air inflow rate specified by the first control unit 17, and the like are displayed. Note that information regarding the pressure detected by the pressure sensor 16 may be displayed on the second display unit 22.

[0043] [Air Permeability Measurement Method] Next, a method for measuring air permeability using the air permeability measuring device 10 will be described with reference to FIGS. 3 to 6. FIG. 3 is a flowchart showing the flow of evaluating the air permeability of the object to be measured by the air permeability measuring device 10. FIG. 4 is a diagram showing the state of measuring the air permeability of the concrete C by the air permeability measuring device 10. Hereinafter, the concrete C shown in FIG. 4 will be used as an example of the object to be measured described above to continue the explanation. Note that the concrete C is used for bridge piers and the like.

[0044] In the air permeability measurement method using the air permeability measuring device 10, an arrangement step (S1), a pressure reduction step (S2), a standby start step (S3), a first measurement step (S4), a second measurement step (S5), a calculation step (S6), a specification step (S7), a display step (S8), and a standby end step (S9) are performed in this order.

[0045] First, the user of the air permeability measuring device 10 connects the pressure sensor 16 to the attachment portion 11d of the attachment 11. Then, the user starts a pressure measurement dedicated application by operating the communication device 20. Hereinafter, the application will be referred to as the "pressure measurement application A".

[0046] Subsequently, in the arrangement step (S1), as shown in FIG. 4, the user abuts the contact portion 11a of the attachment 11 against the surface of the concrete C and attaches the attachment 11 to the surface of the concrete C in close contact via the gasket 12.

[0047] After the configuration process (S1), the user operates the communication device 20 to execute the start of measurement in the pressure measurement application A. When the start of measurement is executed in the pressure measurement application A, the detection of the pressure in the internal space 13a of the cylinder 13 by the pressure sensor 16 and the counting of the elapsed time are started.

[0048] Note that before executing the start of measurement in the pressure measurement application A, the type, material, size, usage purpose, etc. of the measurement object may be recorded in a database (not shown) via the pressure measurement application A. Thereby, it becomes possible to easily perform data management and the like of the measurement by the air permeability measurement device 10.

[0049] Next, in the pressure reduction process (S2), the user grips the handle 144 and applies a tensile force to the side opposite to the surface of the concrete C (the right side in FIG. 4) to the piston head 142, and relatively moves the piston 14 with respect to the cylinder 13. Thereby, the volume of the internal space 13a of the cylinder 13 is increased, and the pressure in the internal space 13a is reduced according to Boyle's law.

[0050] After the pressure reduction process (S2), the user passes the engagement convex portion 143 of the piston 14 through the hole portion 15a of the stopper 15, and then rotates the handle 144 around the axial center of the piston rod 141 to engage the engagement convex portion 143 with the engagement portion 15b, thereby fixing the position of the piston 14.

[0051] Then, the user performs a standby start process (S3) of waiting for a predetermined time with the piston 14 fixed at a predetermined position. The predetermined time is, for example, 60 seconds (see FIG. 5). Note that the elapsed time from the start of measurement of the air permeability of the concrete C by the air permeability measurement device 10 may be displayed on the display unit 16a.

[0052] FIG. 5 is a graph showing the pressure change in the internal space 13a of the cylinder 13 during the measurement of the air permeability of the concrete C by the air permeability measuring device 10. As shown in FIG. 5, after the pressure reduction step (S2), the pressure in the internal space 13a of the cylinder 13 is reduced to -90 [kPa], and as air flows into the internal space 13a from the concrete C, the pressure recovers to -70 [kPa].

[0053] After the standby start step (S3), in the first measurement step (S4), the first pressure P1, which is the pressure in the internal space 13a of the cylinder 13 at time t1, is detected by the pressure sensor 16. As shown in FIG. 5, the first pressure P1 at time t1 is -86 [kPa].

[0054] After the first measurement step (S4), in the second measurement step (S5), the second pressure P2, which is the pressure in the internal space 13a at time t2 after a predetermined measurement time T has elapsed since the first measurement step (S4) was executed, is detected by the pressure sensor 16. The measurement time T is, for example, 30 seconds. As shown in FIG. 5, the second pressure P2 is -77 [kPa].

[0055] After the second measurement step (S5), in the calculation step (S6), the first control unit 17 calculates the air permeability by dividing the pressure difference ΔP obtained by subtracting the first pressure P1 from the second pressure P2 by the measurement time T. The air permeability is {-77 - (-86)} / 30 = 0.30 [kPa / s].

[0056] Subsequently, in the specifying step (S7), the first control unit 17 specifies the air inflow amount corresponding to the calculated air permeability by referring to the air permeability calculated in the calculation step (S6) and the correlation stored in the storage unit 18.

[0057] Here, the correlation relationship stored in the memory unit 18 will be described. FIG. 6 is a diagram showing the correlation relationship between the air permeability rate and the air inflow rate stored in the memory unit 18. In the example shown in FIG. 6, the results of experiments in which the air permeability rate and the air inflow rate were measured while maintaining the depressurized state for 30 seconds are shown under a plurality of conditions. The plurality of conditions include the water-cement ratio W / C, the fine aggregate ratio s / a, the amount of AE material, etc. Note that it is not limited to 30 seconds, and it may be a correlation relationship when depressurized for, for example, 10 seconds. Also, the object to be measured in the experiment of FIG. 6 is not limited to concrete, and it may be made of any material such as mortar. However, it is limited to the data in the region where the pressure change shown in FIG. 5 is linear (the range of t1 to t3 in FIG. 5).

[0058] The air permeability rate is the air permeability rate at the time when the piston 14 is fixed at a predetermined position and maintained for 30 seconds. Also, the air inflow rate is the value read from the scale of the cylinder 13 for the air inflow rate when the depressurized state is maintained for 30 seconds.

[0059] As shown in FIG. 6, the coefficient of determination R 2 = 0.985, and it was found that the air permeability rate and the air inflow rate show a strong correlation. Thereby, it becomes possible to measure the air inflow rate from the air permeability rate without reading the scale of the cylinder 13.

[0060] When an approximate straight line is obtained from the correlation relationship in FIG. 6, a relational expression of y = 61.1x + 0.166 is obtained. Hereinafter, the said relational expression will be referred to as "relational expression X". Here, y represents the air inflow rate, and x represents the air permeability rate. It is assumed that the relational expression X representing the correlation relationship in FIG. 6 is stored in the memory unit 18. Thereby, when the air permeability rate is calculated, the air inflow rate is uniquely specified by inputting the calculated air permeability rate into x of the relational expression X.

[0061] Returning again to the description of the air permeability measurement method using the air permeability measurement device 10. In the above-described calculation step S6, since the air permeability was calculated to be 0.30 [kPa / s], the air inflow rate is specified as y = 61.1 × 0.30 + 0.166 = 18.5 [ml]. In this way, the first control unit 17 specifies the air inflow rate corresponding to the calculated air permeability by referring to the relational expression X (S7: specification step).

[0062] Here, conventionally, when obtaining the air inflow rate, it was necessary to read the air inflow rate in the internal space 13a of the cylinder 13 during the pressure recovery. This reading of the air inflow rate is performed by visually observing the memory engraved on the cylinder 13. Therefore, in order to reduce the reading error, it is preferable that the air inflow rate during the pressure reduction is large. That is, it is preferable that the period from the pressure reduction to the pressure recovery is as long as possible.

[0063] On the other hand, according to the air permeability measurement device 10 of the present embodiment, since the first pressure P1 and the second pressure P2 are detected by the pressure sensor 16, although it depends on the accuracy of the pressure sensor 16, even if the difference between the first pressure P1 and the second pressure P2 is small, each detection error is much smaller than the visual reading of the above-described air inflow rate. That is, it is possible to shorten the time between the detection of the first pressure P1 and the detection of the second pressure P2.

[0064] After the specification step (S7), the communication unit 19 transmits the first pressure P1 detected by the pressure sensor 16 in the first measurement step (S4), the second pressure P2 detected by the pressure sensor 16 in the second measurement step (S5), the air permeability calculated by the first control unit 17 in the calculation step (S6), and the air inflow rate specified by the first control unit 17 to the transmission / reception unit 23 of the communication device 20.

[0065] Next, in the display step (S8), the first pressure P1 and the second pressure P2 are displayed on the display unit 16a of the pressure sensor 16. Also, the air permeability and the air inflow rate are displayed on the second display unit 22. Note that only one of the air permeability or the air inflow rate may be displayed on the second display unit 22. By checking the air permeability or the air inflow rate displayed on the second display unit 22, the user can evaluate the air permeability of the concrete C.

[0066] After the display step (S8), in the standby end step (S9), the user operates the handle 144 to disengage the engaging convex portion 143 of the piston 14 from the engaging portion 15b of the stopper 15, releasing the tensile force on the piston 14.

[0067] As a result, the piston 14 moves toward the concrete C side, and as the volume of the internal space 13a of the cylinder 13 decreases, the pressure in the internal space 13a increases according to Boyle's law, and recompression occurs as shown in the pressure change after time t3 in FIG. 5.

[0068] After the standby end step (S9), the user operates the communication device 20 to execute measurement stop in the pressure measurement application A. When the measurement stop is executed in the pressure measurement application A, the detection of the pressure in the internal space 13a by the pressure sensor 16 stops, and the counting of the elapsed time stops.

[0069] Note that before executing the measurement stop in the pressure measurement application A, the measurement results such as the air permeability and the air inflow rate may be recorded in a database (not shown) via the pressure measurement application A. Thereby, it becomes possible to manage the measurement results by the air permeability measurement device 10.

[0070] Also, in the present embodiment, between S3 and S9 in FIG. 3, the first control unit 17 determines in parallel the presence or absence of air leakage in the attachment 11. Here, FIG. 7 is a flowchart showing the flow of the air leakage detection process by the air permeability measurement device 10.

[0071] As shown in FIG. 7, the first control unit 17 determines whether or not the calculated air permeability is equal to or greater than a predetermined threshold value (S11). When the air permeability is equal to or greater than the threshold value (S11: YES), the first control unit 17 determines that there is an air leak near the attachment 11.

[0072] Here, FIG. 8 is a graph showing the pressure change during measurement by the air permeability measuring device 10 when gaskets 12 made of different materials are used. In FIG. 8, silicon A, silicon B, silicon C, and silicon D show the case where high-hardness silicon is used as the material of the gasket 12. Each high-hardness silicon has different hardness, thickness, etc.

[0073] Also, low hardness A, low hardness B, low hardness C, and low hardness D show the case where low-hardness silicon is used as the material of the gasket 12. Each low-hardness silicon has different hardness, thickness, etc. Further, gel A, gel B, gel C, and gel D show the case where a urethane gel gasket 12 is used. Each urethane gel has different hardness, thickness, etc.

[0074] As shown in FIG. 8, when (1) silicon A to D, low hardness D, and gel D are used as the material of the gasket 12, it can be seen that the pressure rapidly increases immediately after the start of measurement, and an air leak occurs near the attachment 11.

[0075] On the other hand, when (2) low hardness C and gel C are used as the material of the gasket 12, the pressure recovery is completed in about 40 seconds. In contrast, when (3) low hardness A, low hardness B, gel A, and gel B are used as the material of the gasket 12, the depressurized state can be maintained for about 60 seconds.

[0076] When the pressure in the internal space 13a of the cylinder 13 rapidly increases as in the case of (1) described above, the air permeability obtained by dividing the pressure change by the measurement time becomes equal to or greater than the threshold value. When the air permeability becomes equal to or greater than the threshold value (S11: YES), the first control unit 17 transmits an error signal to the transmission / reception unit 23 of the communication device 20 via the communication unit 19.

[0077] When the error signal is received by the transceiver unit 23, the second control unit 21 causes the second display unit 22 to display a predetermined error display (S12). By confirming that the error display is shown on the second display unit 22, the user can quickly grasp that air is leaking from around the contact portion 11a of the attachment 11 or the like. As a result, the user can re-perform the measurement by the air permeability measuring device 10.

[0078] 〔Effect of Embodiment 1〕 According to the air permeability measuring device 10 described above, the first control unit 17 divides the pressure difference ΔP between the first pressure P1 detected by the pressure sensor 16 in the first measurement step (S4) and the second pressure P2 detected by the pressure sensor 16 in the second measurement step (S5) by the measurement time T to calculate the air permeability (S6: calculation step).

[0079] Then, the first control unit 17 can identify the air inflow rate by referring to the data regarding the correlation between the air permeability and the air inflow rate stored in the storage unit 18, and can evaluate the air permeability of the concrete C which is the measurement object.

[0080] On the other hand, in a conventional air permeability measuring device, after the inside of the cylinder is depressurized and waited for a predetermined time (for example, 60 seconds), the amount of air flowing into the inside of the cylinder is obtained by reading the scale of the cylinder.

[0081] In contrast, according to the air permeability measuring device 10, after the second measurement step (S5), without reading the scale of the cylinder 13, by referring to the data regarding the correlation stored in advance in the storage unit 18, the air inflow rate corresponding to the calculated air permeability can be immediately identified. Therefore, the measurement time by the air permeability measuring device 10 can be reduced to about half (about 30 seconds) of the conventional time, and the air permeability of the concrete C can be evaluated in a short time.

[0082] Also, in the display step (S8), the first control unit 17 displays the first pressure P1 detected in the first measurement step (S4) and the second pressure P2 detected in the second measurement step (S5) on the display unit 16a. Further, the second display unit 22 of the communication device 20 displays the air permeability calculated in the calculation step (S6) and the air inflow rate specified in the specification step (S7). Thereby, the user can quickly grasp the air inflow rate by visually recognizing the second display unit 22 of the communication device 20 without reading the scale of the cylinder 13.

[0083] Also, since the air permeability measuring device 10 is not a device that performs depressurization using a vacuum pump or the like, it does not require a power source for driving a vacuum pump or the like, and can evaluate the air permeability of the surface layer of the concrete C with an inexpensive and simple configuration.

[0084] Also, in the placement step (S1), the attachment 11 can be placed in close contact with the surface of the concrete C, which is the measurement object, via the gasket 12, so that the air permeability measuring device 10 can satisfactorily evaluate the air permeability of the concrete C.

[0085] Also, the pressure sensor 16 is attached to the attachment portion 11d of the attachment 11 and connected to the communication hole 11e communicating with the internal space 13a of the cylinder 13 and the opening 11b of the attachment 11, so that the pressure sensor 16 can be stably arranged and the pressure in the internal space 13a of the cylinder 13 can be accurately detected.

[0086] Also, since data regarding the correlation between the air permeability and the air inflow rate is stored in advance in the storage unit 18, after the first control unit 17 calculates the air permeability, by referring to the above data, the air inflow rate corresponding to the calculated air permeability can be quickly specified.

[0087] Also, the first control unit 17 determines in parallel the presence or absence of air leakage in the attachment 11 between S3 and S9 in FIG. 3. When the air permeability is equal to or higher than a predetermined threshold value (S11: YES), it is determined that air leakage has occurred, and an error is displayed on the second display unit 22 (S12). After the user confirms the error display, by restarting the measurement of air permeability by the air permeability measuring device 10 from the placement step (S1), it becomes possible to appropriately evaluate the air permeability of the object to be measured.

[0088] In addition, since the first measurement step (S4) and the second measurement step (S5) are performed before the standby end step (S9), the measurement time T can be shortened.

[0089] The communication unit 19 of the air permeability measuring device 10 transmits information regarding the pressure in the internal space 13a of the cylinder 13 detected by the pressure sensor 16, the air permeability calculated by the first control unit 17, and the air inflow amount specified by the first control unit 17 to the transmission / reception unit 23 of the communication device 20. The second display unit 22 displays each piece of information transmitted from the communication unit 19. Thereby, the user can quickly grasp the measurement result by visually recognizing the second display unit 22 of the communication device 20.

[0090] 〔Embodiment 2〕 Next, Embodiment 2 of the present disclosure will be described with reference to FIG. 9. For convenience of explanation, members having the same functions as those described in Embodiment 1 above are denoted by the same reference numerals, and the description thereof will not be repeated. FIG. 9 is a block diagram showing the configuration of an air permeability measuring device 10A according to Embodiment 2.

[0091] As shown in FIG. 9, the air permeability measuring device 10A includes a pressure sensor 16, a control device 101A, and a first display unit 102. The control device 101A has a first control unit 17 and a storage unit 18. In Embodiment 2, instead of displaying the air permeability and the air inflow amount on the second display unit 22 of the communication device 20, the air permeability and the air inflow amount are displayed on the first display unit 102 of the air permeability measuring device 10A.

[0092] The air permeability measuring device 10A includes an attachment 11, a gasket 12, a cylinder 13, a piston 14, and a stopper 15, similar to the air permeability measuring device 10 of Embodiment 1 (see FIG. 2). Note that the air permeability measuring device 10A is not configured to be communicable with the communication device 20.

[0093] The first display unit 102 is separate from the pressure sensor 16 and is a dedicated display for displaying the measurement results by the air permeability measuring device 10A. The first display unit 102 is constituted by a liquid crystal display device (LCD; Liquid Crystal Display), an organic EL (Electro-Luminescence) display, or the like.

[0094] The first display unit 102 is connected to the first control unit 17 via wired communication or wireless communication. The air permeability and the air inflow amount calculated by the first control unit 17 are displayed on the first display unit 102. Note that a plurality of first display units 102 may be provided.

[0095] Also in the air permeability measuring device 10A of Embodiment 2 described above, the same effects as those of the air permeability measuring device 10 of Embodiment 1 can be obtained. In particular, even when the user does not carry the communication device 20, the user can evaluate the air permeability of the concrete C in a short time by visually recognizing the first display unit 102.

[0096] 〔Other Embodiments〕 In the air permeability measuring device 10 of Embodiment 1 described above, the air permeability and the air inflow amount are displayed on the second display unit 22 of the communication device 20, but the present invention is not limited to this. A first display unit separate from the pressure sensor 16 may be provided in the air permeability measuring device 10, and the air permeability and the air inflow amount may be displayed on both the first display unit and the second display unit 22.

[0097] In the above-described Embodiments 1 and 2, as the method for fixing the piston 14, a configuration in which the engaging convex portion 143 of the piston rod 141 is engaged with the hole portion 15a of the stopper 15 is adopted, but the present invention is not limited thereto. For example, a concave portion may be provided in the piston rod 141 and a convex portion may be provided in the stopper 15, and the convex portion of the stopper 15 may be engaged with the concave portion of the piston rod 141.

[0098] Further, in the above-described Embodiments 1 and 2, the user operates the handle 144 to relatively move the piston 14 with respect to the cylinder 13, but the present invention is not limited thereto. For example, an actuator that moves the handle 144 along the longitudinal direction of the cylinder 13 may be provided in the air permeability measuring device 10. In this case, the actuator is remotely operated to move the piston 14 with respect to the cylinder 13 by controlling the first control unit 17 via the communication unit 19 by the communication device 20.

[0099] Further, in the above-described Embodiment 1, the first control unit 17 calculates the air permeability and specifies the air inflow amount corresponding to the calculated air permeability, but the present invention is not limited thereto. For example, the pressure value detected by the pressure sensor 16 may be transmitted to the communication device 20 via the communication unit 19, and the second control unit 21 of the communication device 20 may calculate the air permeability and specify the air inflow amount. The second display unit 22 displays the air permeability calculated by the second control unit 21 and the air inflow amount specified by the second control unit 21.

[0100] The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present disclosure.

Description of Reference Numerals

[0101] 10 Air permeability measuring device 10A Air permeability measuring device 11 Attachment 11a Contact portion 11b Opening 11e Communication hole 12 Gasket 13 Cylinder 13a Internal space 14 Piston 16 Pressure sensor 17 First control unit 18 Memory unit 19 Communication unit 20 Communication device 21 Second control unit 22 Second display unit 100 Air permeability measurement system 102 First display unit

Claims

1. An attachment disposed on the surface of an object to be measured and having an opening facing the object to be measured, a cylinder having an internal space communicating with the opening of the attachment and fixed to the attachment, a piston that slides on the inner peripheral surface of the cylinder to change the volume of the internal space, a pressure sensor that detects the pressure of the internal space through the opening of the attachment, a control unit, comprising: The control unit: In a state where the attachment is in close contact with the surface of the object to be measured, a first pressure which is the pressure of the internal space at a certain time after applying a tensile force to the piston to decompress, and a second pressure which is the pressure of the internal space after a predetermined measurement time has elapsed from the time when the first pressure was detected are calculated, and by dividing the pressure difference by the measurement time, a ventilation rate which is an index for evaluating the air permeability of the object to be measured is calculated, By referring to the correlation between the calculated ventilation rate and the air inflow amount which is the amount of air flowing into the internal space when the internal space is decompressed, the air inflow amount corresponding to the ventilation rate is specified, The predetermined measurement time is a time when the correlation is shown based on measurement data between the ventilation rate and the air inflow amount, The correlation is determined based on measurement data acquired in advance, A ventilation measuring device characterized by the above.

2. The ventilation measuring device according to claim 1, further comprising a first display unit that displays information regarding at least one of the pressure of the internal space detected by the pressure sensor, the ventilation rate calculated by the control unit, and the air inflow amount specified by the control unit.

3. Further comprising a gasket disposed between the surface of the object to be measured and the attachment and in close contact with the surface of the object to be measured, The attachment is disposed in close contact with the surface of the object to be measured via the gasket. The ventilation measuring device according to claim 1.

4. The attachment has a communication hole communicating with the opening on its outer peripheral surface, The pressure sensor is connected to the communication hole of the attachment. The ventilation measuring device according to claim 1.

5. The ventilation measuring device according to claim 1, further comprising a storage unit in which data regarding the correlation is stored.

6. The ventilation measurement device further includes a communication unit that transmits information regarding at least one of the pressure of the internal space, the ventilation rate, and the air inflow rate detected by the pressure sensor to a communication device. The ventilation measurement device according to claim 1, wherein the communication unit transmits data for causing the communication device to display the information to the communication device.

7. The control unit further determines that there is an air leak when the calculated ventilation rate is equal to or greater than a predetermined threshold value. The ventilation measurement device according to claim 1.

8. A ventilation measurement method using the ventilation measurement device according to any one of claims 1 to 7, an arrangement step of arranging the attachment on the surface of the object to be measured, a depressurization step of depressurizing the internal space of the cylinder by applying the tensile force to the piston and slidingly moving the piston, a standby start step of starting to standby with the piston fixed at a predetermined position after the execution of the depressurization step, a first measurement step of detecting, by the pressure sensor, a first pressure that is the pressure of the internal space at a certain time after the standby start step, a second measurement step of detecting, by the pressure sensor, a second pressure that is the pressure of the internal space when the measurement time has elapsed after the execution of the first measurement step after the standby start step, a calculation step of calculating the ventilation rate by dividing the pressure difference, which is the difference between the second pressure and the first pressure, by the measurement time by the control unit, a specifying step of specifying the air inflow rate corresponding to the ventilation rate by referring to the correlation between the ventilation rate calculated by the control unit and the air inflow rate, which is the amount of air flowing into the internal space due to the depressurization of the internal space, characterized by including. The ventilation measurement method.

9. The ventilation measurement method according to claim 8, further including a display step of displaying information regarding at least one of the pressure detected in the first measurement step and the second measurement step, the ventilation rate calculated in the calculation step, and the air inflow rate specified in the specifying step on a first display unit.

10. The ventilation measurement method according to claim 8, further including a standby end step of releasing the fixation of the piston after the standby start step, wherein the first measurement step and the second measurement step are performed before the standby end step. The ventilation measurement method according to claim 8.

11. The air permeability measuring device according to any one of claims 1 to 7, A communication device capable of communicating with the air permeability measuring device, Comprising, The air permeability measuring device further includes a communication unit that transmits information regarding at least one of the pressure in the internal space detected by the pressure sensor, the air permeability calculated by the control unit, and the air inflow amount specified by the control unit to the communication device. The communication device has a second display unit that displays the information transmitted from the communication unit, and is characterized by an air permeability measurement system.

12. An attachment disposed on the surface of the object to be measured and having an opening facing the object to be measured, A cylinder having an internal space communicating with the opening of the attachment and fixed to the attachment, A piston that changes the volume of the internal space by sliding on the inner peripheral surface of the cylinder, A pressure sensor that detects the pressure in the internal space through the opening of the attachment, An air permeability measuring device comprising, A communication device capable of communicating with the air permeability measuring device, Comprising, The air permeability measuring device further includes a communication unit that transmits information regarding the pressure in the internal space detected by the pressure sensor to the communication device. The communication device, A control unit, A second display unit, Having, The control unit, In a state where the attachment is in close contact with the surface of the object to be measured, a first pressure that is the pressure in the internal space at a certain time after applying a tensile force to the piston to reduce the pressure and a second pressure that is the pressure in the internal space after a predetermined measurement time has elapsed from the time when the first pressure was detected are calculated, and the pressure difference between them is calculated. By dividing the pressure difference by the measurement time, the air permeability, which is an index for evaluating the air permeability of the object to be measured, is calculated. By referring to the correlation between the calculated air permeability and the air inflow amount, which is the amount of air flowing into the internal space when the internal space is depressurized, the air inflow amount corresponding to the air permeability is specified. The second display unit displays information regarding the air permeability calculated by the control unit and the air inflow amount specified by the control unit. The predetermined measurement time is a time when the correlation is shown based on measurement data between the air permeability and the air inflow amount. The correlation is determined based on measurement data acquired in advance. Characterized by an air permeability measurement system.

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