Inspection method

Abstract

An inspection apparatus (10) according to the present disclosure comprises a control unit (13) for inspecting the state of being filled with a repairing material in a crack depth direction, on the basis of the propagation speed of ultrasonic waves that are emitted by a transmission probe (2) into concrete C, that are diffracted by a crack C sandwiched between the transmission probe (2) and a reception probe (3) which are equidistant from the crack C, and that are received by the reception probe (3).

Description

Testing method

[0001] This disclosure relates to an inspection method.

[0002] To repair cracks in concrete, a repair material is filled into the cracks. While the degree of repair material filling in the width and length of the cracks can be inspected visually, it is difficult to visually inspect the degree of repair material filling in the depth of the cracks.

[0003] One method for inspecting the filling of repair material in the depth direction of cracks is destructive testing (see Non-Patent Literature 1). In this method, the filling of repair material in the depth direction of cracks can be inspected by taking core samples from the concrete.

[0004] Naito et al., "Study on a method for evaluating filling after crack injection using small-diameter cores," Proceedings of the 8th Annual Scientific Conference of the Japan Society of Civil Engineers, V-390 (September 2013).

[0005] The technology described in Non-Patent Document 1 requires the destructive removal (core drilling) of concrete. However, from the standpoint of work efficiency, there is a need for a non-destructive technology to inspect the state of filling of repair material in the depth direction of cracks.

[0006] In light of the problems described above, the purpose of this disclosure is to provide an inspection method that can non-destructively inspect the state of filling of concrete cracks with repair material in the depth direction.

[0007] An inspection method according to one embodiment is an inspection method performed by an inspection device for inspecting the depth-direction filling state of a repair material into a crack in concrete, wherein the inspection method is performed based on the propagation speed of ultrasonic waves diffracted by the crack, which are radiated into the interior of the concrete by a transmitting probe and received by a receiving probe positioned equidistant from the transmitting probe across the crack, and the depth-direction filling state of the repair material into the crack is inspected.

[0008] According to this disclosure, the state of filling of repair material in the depth direction of concrete cracks can be inspected non-destructively.

[0009] This figure shows an example of the configuration of an inspection system including an inspection device according to one embodiment of the present disclosure. This figure shows an example of the inspection flow using the inspection system shown in Figure 1. This figure is for explaining the inspection of the state of filling of repair material in the depth direction of a crack using the inspection device shown in Figure 1. This figure shows an example of the distribution of the relative ultrasonic propagation velocity coefficient.

[0010] Embodiments of this disclosure will be described below with reference to the drawings.

[0011] Figure 1 is a diagram showing an example of the configuration of an inspection system 1 including an inspection device 10 according to one embodiment of the present disclosure.

[0012] As shown in Figure 1, the inspection system 1 according to this disclosure comprises a transmitting probe 2, a receiving probe 3, and an inspection device 10.

[0013] As shown in Figure 1, the transmitting probe 2 is positioned on the concrete surface at a distance d from the crack C and emits ultrasonic waves into the concrete.

[0014] As shown in Figure 1, the receiving probe 3 is positioned on the concrete surface at an equidistant distance (i.e., distance d) from the transmitting probe 2, with a crack C in between. The receiving probe 3 receives ultrasonic waves emitted by the transmitting probe 2 and diffracted by the crack C.

[0015] The ultrasonic waves emitted from the transmitting transducer 2 cannot propagate through the cavity formed by the crack C, and instead diffract at the boundary between the cavity formed by the crack C and the concrete, as shown in Figure 1. Here, the angle of incidence of the ultrasonic waves that reach the boundary between the cavity formed by the crack C and the concrete is perpendicular to the angle of reflection of the ultrasonic waves diffracted (reflected) at the boundary. Hereafter, the ultrasonic waves diffracted by the crack C may be referred to as "orthogonal diffracted waves".

[0016] As described above, the ultrasonic waves that reach crack C are reflected with their direction of propagation bent by 90°. Therefore, as shown in Figure 1, by arranging the transmitting probe 2 and the receiving probe 3 at equal distances across crack C, when ultrasonic waves emitted from the transmitting probe 2 at an incident angle of 45° reach the boundary between the cavity formed by crack C and the concrete, the ultrasonic waves diffracted at the boundary (orthogonal diffracted waves) can be received by the receiving probe 3.

[0017] The inspection device 10 is a device for inspecting the filling state of repair materials such as acrylic emulsion, epoxy, polyurea, and acrylic in the depth direction of cracks C that have occurred in concrete. As shown in Figure 1, the inspection device 10 comprises a storage unit 11, a communication unit 12, and a control unit 13.

[0018] The storage unit 11 includes at least one semiconductor memory, at least one magnetic memory, at least one optical memory, or any combination thereof. The semiconductor memory is, for example, RAM (Random Access Memory), ROM (Read Only Memory), or flash memory. The RAM is, for example, SRAM (Static Random Access Memory) or DRAM (Dynamic Random Access Memory). The ROM is, for example, EEPROM (Electrically Erasable Programmable Read Only Memory). The flash memory is, for example, an SSD (Solid-State Drive). The magnetic memory is, for example, an HDD (Hard Disk Drive). The storage unit 11 functions, for example, as a main memory, an auxiliary memory, or a cache memory. The storage unit 11 stores information used for the operation of the inspection device 10 and information obtained by the operation of the inspection device 10.

[0019] The communication unit 12 includes at least one communication module. The communication module is, for example, a module compatible with a LAN communication standard such as Ethernet®. The communication unit 12 receives information used for the operation of the inspection device 10 and transmits information obtained by the operation of the inspection device 10.

[0020] The control unit 13 includes at least one processor, at least one programmable circuit, at least one dedicated circuit, or any combination thereof. The processor is a general-purpose processor such as a CPU (Central Processing Unit) or GPU (Graphics Processing Unit), or a dedicated processor specialized for a specific process. The programmable circuit is, for example, an FPGA (Field-Programmable Gate Array). The dedicated circuit is, for example, an ASIC (Application Specific Integrated Circuit). The control unit 13 controls each part of the inspection device 10 and executes processes related to the operation of the inspection device 10. For example, the control unit 13 inspects the state of filling of the repair material in the depth direction of the crack C based on the propagation speed of ultrasonic waves diffracted by the crack C, which are radiated into the concrete by the transmitting probe 2 and received by the receiving probe 3, which is positioned equidistant from the transmitting probe 2 across the crack C.

[0021] The functions of the inspection device 10 are realized by executing the program according to this embodiment on the processor, which acts as the control unit 13. In other words, the functions of the inspection device 10 are realized by software. The program causes the computer to perform the operations of the inspection device 10, thereby causing the computer to function as the inspection device 10. That is, the computer operates as the inspection device 10 by performing the operations of the inspection device 10 according to the program.

[0022] The program can be stored on a non-temporary computer-readable medium. Examples of non-temporary computer-readable mediums include flash memory, magnetic recording devices, optical discs, magneto-optical recording media, or ROM. The program can be distributed, for example, by selling, transferring, or leasing portable media such as SD (Secure Digital) cards, DVDs (Digital Versatile Discs), or CD-ROMs (Compact Disc Read Only Memory) on which the program is stored. The program may also be distributed by storing it in server storage and transferring it from the server to other computers. The program may also be provided as a program product.

[0023] A computer, for example, stores a program stored on a portable medium or a program transferred from a server in its main memory. Then, the computer reads the program stored in the main memory with its processor and executes the processing according to the read program. The computer may also read the program directly from the portable medium and execute the processing according to the program. The computer may also execute the processing according to the received program sequentially each time a program is transferred to it from a server. Processing may also be performed by a so-called ASP (Application Service Provider) type service, which does not transfer programs from the server to the computer, but realizes its function only through execution instructions and result retrieval. A program includes information used for processing by an electronic computer that is equivalent to a program. For example, data that is not a direct instruction to the computer but has the nature of defining the computer's processing falls under "equivalent to a program".

[0024] Some or all of the functions of the inspection device 10 may be implemented by a programmable circuit or a dedicated circuit as the control unit 13. In other words, some or all of the functions of the inspection device 10 may be implemented by hardware.

[0025] Next, the inspection of the filling state of the repair material into the crack C by the inspection system 1 according to the present embodiment will be described. FIG. 2 is a diagram showing an example of an inspection flow of the filling state of the repair material into the crack C by the inspection system 1, and is a diagram for explaining an inspection method executed by the inspection device 10 according to the present embodiment.

[0026] First, the width and length of the crack C generated in the concrete are measured by an inspection by an operator or the like (step S11).

[0027] Next, the depth of the crack C is measured (step S12). When the repair material is not filled in the crack C, when the ultrasonic wave radiated by the transmission probe 2 reaches the end in the depth direction of the crack C, it diffracts at a right angle and becomes an orthogonal diffracted wave. Here, as shown in FIG. 1, by installing the transmission probe 2 and the reception probe 3 at a position separated from the crack C by a distance d so that the ultrasonic wave radiated at an incident angle of 45° by the transmission probe 2 reaches the end in the depth direction of the crack C, the orthogonal diffracted wave diffracted at the end in the depth direction of the crack C can be received by the reception probe 3. Since the distance d can be measured, the depth of the crack C can be measured from the distance d when the orthogonal diffracted wave is received by the reception probe 3.

[0028] When the width, length, and depth of the crack C are measured, the repair material to be filled in the crack C and the filling amount are determined (step S13). The filling amount of the repair material can be determined based on the measured width, length, and depth of the crack C.

[0029] The determined repair material is filled into the crack C by the determined filling amount, and the crack C is repaired (step S14).

[0030] After the repair of the crack C is carried out, the inspection device 10 inspects the filling state of the repair material in the depth direction of the crack C (step S15). The inspection device 10 (control unit 13) irradiates the inside of the concrete with the transmitting probe 2 and is received by the receiving probe 3 arranged at an equal distance from the transmitting probe 2 across the crack C. Based on the propagation speed of the ultrasonic wave diffracted by the crack C, the filling state of the repair material in the depth direction of the crack C is inspected. The details of inspecting the filling state of the repair material in the crack C will be described later.

[0031] Based on the inspection result by the inspection device 10, for example, it is determined by the operator whether the crack C is sufficiently filled with the repair material (step S16).

[0032] If it is determined that the crack C is not sufficiently filled with the repair material (step S16: No), the process returns to the process of step S14, and the crack C is filled with the repair material again. If it is determined that the crack C is sufficiently filled with the repair material (step S16: Yes), the repair of the crack C is considered completed, and the process ends.

[0033] Next, the details of the inspection by the control unit 13 of the inspection device 10 for the filling state of the repair material in the depth direction of the crack C will be described.

[0034] The control unit 13 calculates the propagation speed V of the ultrasonic wave when the inspection location of the filling state is irradiated with the ultrasonic wave. ｉ It is calculated by the following formula (1). V ｉ = L / T Formula (1)

[0035] In formula (1), L is the propagation distance of the ultrasonic wave, which is the distance from the transmitting probe 2 to the receiving probe 3 through the diffraction position of the ultrasonic wave. T is the propagation time of the ultrasonic wave, which is the time from when the ultrasonic wave is radiated from the transmitting probe 2 until the orthogonal diffracted wave is received at the receiving probe 3. Generally, when the repair material is sufficiently filled and the ultrasonic wave is irradiated on the location where the filled repair material has hardened (filled completion location), since the repair material is in an integrated state with the concrete, the propagation speed V ｉIt becomes equivalent to the ultrasonic propagation speed in sound concrete. On the other hand, when ultrasonic waves are irradiated on a portion where the repair material is not sufficiently filled or a portion where the filled repair material has not hardened (uncompleted filling portion), the propagation speed Vi becomes slower compared to the case where ultrasonic waves are irradiated on the completed filling portion.

[0036] The control unit 13 calculates the ultrasonic propagation speed V ｉ Based on this, the relative ultrasonic propagation speed coefficient R ｖ at the inspection location of the filling state is calculated by the following formula (2). R ｖ = V ｉ ２ / V ０ ２ Formula (2)

[0037] In formula (2), V ０ is the maximum ultrasonic propagation speed and is the ultrasonic propagation speed in sound concrete. That is, the control unit 13 sets the ultrasonic propagation speed in sound concrete as V ０ and sets the ultrasonic propagation speed when ultrasonic waves are irradiated on the measurement location of the filling state as V ｉ Then, the relative ultrasonic propagation speed coefficient R ｖ is calculated by the above-mentioned formula (2). And the control unit 13 inspects the filling state of the repair material at the measurement location based on the calculated relative ultrasonic propagation speed coefficient R ｖ .

[0038] As described above, when ultrasonic waves are irradiated on the completed filling portion, the propagation speed V ｉ becomes equivalent to the maximum ultrasonic propagation speed V ０ . On the other hand, when ultrasonic waves are irradiated on the uncompleted filling portion, the propagation speed Vi becomes slower compared to the case where ultrasonic waves are irradiated on the completed filling portion. That is, when ultrasonic waves are irradiated on the completed filling portion, the relative ultrasonic propagation speed coefficient R ｖ becomes larger. Also, when ultrasonic waves are irradiated on the uncompleted filling portion, the relative ultrasonic propagation speed coefficient R ｖ becomes smaller. Therefore, the control unit 13 can inspect the filling state of the repair material at the measurement location based on the relative ultrasonic propagation speed coefficient R ｖ .

[0039] A specific example of inspecting the filling state in the depth direction of crack C will be explained with reference to Figure 3. As mentioned above, the depth of crack C is measurable. Therefore, for example, as shown in Figure 3, when ultrasonic waves emitted from the transmitting probe 2 at an incident angle of 45° reach the end of crack C, the transmitting probe 2 and the receiving probe 3 are moved equidistantly toward crack C, and ultrasonic waves are emitted by the transmitting probe 2. At the locations where the repair material has been filled, the emitted ultrasonic waves diffract, and the orthogonal diffracted waves are received by the receiving probe 3. Therefore, while the transmitting probe 2 and the receiving probe 3 are moved equidistant toward crack C, the propagation speed V ｉ The relative ultrasonic propagation velocity coefficient R is measured. ｖ By calculating this, it is possible to inspect the filling state of the repair material along the depth direction of crack C.

[0040] The control unit 13 determines the relative ultrasonic wave propagation velocity coefficient R for multiple locations in the concrete. ｖ We determine the relative ultrasonic propagation velocity coefficient R, as shown in Figure 4. ｖ The distribution of these can also be output. This allows us to identify areas where the repair material is sufficiently filled and areas where it is insufficient throughout the entire concrete structure. For example, in the example shown in Figure 4, it can be seen that the repair material is insufficiently filled in the upper part of the paper.

[0041] Furthermore, the control unit 13 controls the relative ultrasonic propagation velocity coefficient R ｖ Based on this, the hardening state of the repair material injected into crack C may be further inspected. As described above, when ultrasonic waves are irradiated onto areas where the repair material filled in crack C has not hardened sufficiently, the propagation speed of the ultrasonic waves V ｉ The propagation speed V of the ultrasonic waves irradiated to the area will be slower as the filled repair material hardens. ｉ It becomes larger (i.e., the relative ultrasonic propagation velocity coefficient R ｖ (The relative ultrasonic propagation velocity coefficient R becomes larger). Therefore, for example, when ultrasound is irradiated to the same location at intervals, the control unit 13 determines the relative ultrasonic propagation velocity coefficient R ｖ Based on the changes, it may be determined whether or not the repair material has been filled, and whether or not the filled repair material has hardened.

[0042] As described above, the inspection device 10 according to this embodiment includes a control unit 13. The control unit 13 inspects the state in which the repair material fills the crack C in the depth direction based on the propagation speed of ultrasonic waves diffracted by the crack C, which are radiated into the concrete by the transmitting probe 2 and received by the receiving probe 3 which is positioned equidistant from the transmitting probe 2 across the crack C.

[0043] The propagation speed of ultrasonic waves changes depending on the state in which the repair material is filled into the crack C. Therefore, based on the propagation speed of ultrasonic waves diffracted by the crack C, which are radiated into the concrete by the transmitting probe 2 and received by the receiving probe 3, it is possible to non-destructively inspect the state in which the repair material is filled into the crack C in the concrete in the depth direction.

[0044] The following additional information is disclosed regarding the embodiments described above.

[0045] [Addendum 1] An inspection method performed by an inspection device for inspecting the depth-direction filling state of a repair material into a crack in concrete, wherein the inspection method involves radiating ultrasonic waves into the interior of the concrete by a transmitting probe and receiving them with respect to the crack, and based on the propagation speed of ultrasonic waves diffracted by the crack, the depth-direction filling state of the crack.

[0046] [Note 2] In the inspection method described in Note 1, the propagation speed of ultrasonic waves in sound concrete is V ０ Let V be the propagation speed of the ultrasonic waves when the ultrasonic waves are irradiated onto the measurement point of the filled state. ｉ Therefore, according to equation (2) above, the relative ultrasonic propagation velocity coefficient R ｖ The relative ultrasonic propagation velocity coefficient R calculated above is then used to calculate the relative ultrasonic propagation velocity coefficient R. ｖ An inspection method for inspecting the filling state at the measurement point based on the above.

[0047] [Note 3] In the inspection method described in Note 2, the relative ultrasonic wave propagation velocity coefficient R ｖ An inspection method for further examining the hardening state of the repair material injected into the cracks, based on the above.

[0048] [Appendix 4] An inspection device for inspecting the depth-direction filling state of a repair material into a crack in concrete, comprising a control unit, wherein the control unit is configured to inspect the depth-direction filling state of the repair material into the crack based on the propagation speed of ultrasonic waves diffracted by the crack, which are radiated into the interior of the concrete by a transmitting probe and received by a receiving probe positioned equidistant from the transmitting probe across the crack.

[0049] [Note 5] A program that causes the computer to operate as the testing device described in Note 4.

[0050] [Appendix 6] A non-temporary storage medium storing a program executable by a computer, the non-temporary storage medium storing a program that causes the computer to operate as the inspection device described in Appendix 4.

[0051] Although the embodiments described above are representative examples, it will be apparent to those skilled in the art that many modifications and substitutions are possible within the spirit and scope of this disclosure. Therefore, the present invention should not be construed as being limited by the embodiments described above, and various modifications or changes are possible without departing from the claims. For example, it is possible to combine multiple component blocks shown in the configuration diagram of the embodiments into one, or to divide one component block.

[0052] 10 Inspection device 11 Storage unit 12 Communication unit 13 Control unit

Claims

1. An inspection method performed by an inspection device for inspecting the depth-direction filling state of a repair material into a crack in concrete, the inspection method comprising: inspecting the depth-direction filling state of the repair material into the crack based on the propagation speed of ultrasonic waves diffracted by the crack, which are radiated into the interior of the concrete by a transmitting probe and received by a receiving probe positioned equidistant from the transmitting probe across the crack.

2. In the inspection method according to claim 1, the ultrasonic propagation speed in sound concrete is V ０ and when the ultrasonic wave is irradiated to the measurement location of the filling state, the ultrasonic propagation speed is V ｉ Then, the relative ultrasonic propagation speed coefficient R ｖ is calculated by the following formula (1), and based on the calculated relative ultrasonic propagation speed coefficient R ｖ the inspection method for inspecting the filling state at the measurement location is as follows. R ｖ = V ｉ ２ / V ０ ２ Formula (1) 3. In the inspection method according to claim 2, the relative ultrasonic propagation velocity coefficient R ｖ An inspection method for further examining the hardening state of the repair material injected into the cracks, based on the above.

Images