Integrity evaluation method and integrity evaluation device

Abstract

To provide an integrity evaluation method and an integrity evaluation device that are capable of relatively easily verifying the integrity between a reinforced member and a reinforcing portion.SOLUTION: A reinforced column 1 comprises an existing column portion 3 and a reinforcing portion 5 mounted on a surface of the existing column portion 3 so as to be integrated with the existing column portion 3. An integrity evaluation method for evaluating the integrity between the existing column portion 3 and the reinforcing portion 5 in the reinforced column comprises: a measurement step of using optical fiber sensors 11, 12 mounted on either the existing column portion 3 or the reinforcing portion 5 to measure vibration response and / or strain at sites where the optical fiber sensors 11, 12 are mounted; and an integrity determination step of determining the integrity between the existing column portion 3 and the reinforcing portion 5 based on the measurement results obtained in the measurement step.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for evaluating integrity and an apparatus for evaluating integrity.

Background Art

[0002] Conventionally, as an example of a reinforcement method for installing a reinforcing part on the surface of a member to be reinforced, for example, a winding method is known (see, for example, Patent Document 1 below). The winding method aims to address the aging deterioration of existing structures and ensure seismic performance, and involves winding the periphery of an existing member with reinforced concrete or mortar to improve ductility and enhance load-bearing capacity. Further, as another example of the above reinforcement method, there is a cross-section repair method.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Reinforced structures by this type of reinforcement method are designed based on the assumption that the member to be reinforced and the reinforcing part behave integrally. Therefore, it is necessary to confirm the integrity between the member to be reinforced and the reinforcing part. For example, the integrity between the member to be reinforced and the reinforcing part can also be confirmed by micro-destruction inspection or non-destructive inspection of the reinforced structure. However, various sensors, devices, systems, etc. are required for these inspections, and the inspection work is also significant. In view of this problem, an object of the present invention is to provide a method for evaluating integrity and an apparatus for evaluating integrity that can relatively easily confirm the integrity between the member to be reinforced and the reinforcing part.

Means for Solving the Problems

[0005] The gist of the present invention resides in the following [1] to [8].

[0006] 〔1〕In a reinforcing structure including a member to be reinforced and a reinforcing portion provided on the surface of the member to be reinforced so as to be integrated with the member to be reinforced, an integrality evaluation method for evaluating the integrality between the member to be reinforced and the reinforcing portion, the method comprising: a measurement step of measuring the vibration response and / or strain of a portion where an optical fiber sensor is installed by using the optical fiber sensor installed on the member to be reinforced or the reinforcing portion; and an integrality determination step of determining the integrality based on the measurement result obtained in the measurement step.

[0007] 〔2〕In the measurement step, the vibration response and / or strain of the member to be reinforced is measured by using the optical fiber sensor installed on the member to be reinforced, and the method further comprises a second measurement step of measuring the vibration response and / or strain of the reinforcing portion by using a second optical fiber sensor installed on the reinforcing portion and extending along the optical fiber sensor. In the integrality determination step, the integrality is determined based on a comparison between the measurement result obtained in the measurement step and the measurement result obtained in the second measurement step. The integrality evaluation method according to 〔1〕.

[0008] 〔3〕The integrality evaluation method according to 〔2〕, further comprising: a first optical fiber sensor installation step of installing the optical fiber sensor on the surface of the member to be reinforced in a reinforcement work of reinforcing the member to be reinforced with the reinforcing portion to construct the reinforcing structure; and a second optical fiber sensor installation step of installing the second optical fiber sensor on a reinforcing material embedded in the reinforcing portion in the reinforcement work.

[0009] 〔4〕In the measurement step, the vibration response and / or strain of the member to be reinforced is measured by using the optical fiber sensor installed on the member to be reinforced. In the integrality determination step, the integrality is determined based on a comparison between the measurement result obtained in the measurement step and the measurement result of the vibration response and / or strain of the member to be reinforced before reinforcement, which was measured in advance by using the optical fiber sensor before the reinforcing portion is constructed. The integrality evaluation method according to 〔1〕.

[0010] 〔5〕In the integrity determination step, the integrity is determined based on a comparison between the measurement result obtained in the measurement step and the measurement result of the vibration response and / or strain measured using the optical fiber sensor in the past, in the integrity evaluation method according to 〔1〕.

[0011] 〔6〕An integrity evaluation device for evaluating the integrity between a member to be reinforced and a reinforcing portion provided on the surface of the member to be reinforced so as to be integrated with the member to be reinforced, the integrity evaluation device including: a vibration response measurement unit that is connected to a first optical fiber sensor provided on the member to be reinforced and measures the vibration response of the member to be reinforced using the first optical fiber sensor, and that is connected to a second optical fiber sensor provided on the reinforcing portion and measures the vibration response of the reinforcing portion using the second optical fiber sensor; and an arithmetic unit that determines the integrity based on a comparison between the vibration response of the member to be reinforced and the vibration response of the reinforcing portion obtained from the vibration response measurement unit.

[0012] 〔7〕An integrity evaluation method for evaluating the integrity between a member to be reinforced and a reinforcing portion provided on the surface of the member to be reinforced so as to be integrated with the member to be reinforced, the integrity evaluation method including: a first measurement step of measuring the vibration response of the member to be reinforced using a first optical fiber sensor provided on the member to be reinforced; a second measurement step of measuring the vibration response of the reinforcing portion using a second optical fiber sensor provided on the reinforcing portion and extending along the first optical fiber sensor; and an integrity determination step of determining the integrity based on a comparison between the measurement result obtained in the first measurement step and the measurement result obtained in the second measurement step.

[0013] In the integration determination step, when the vibration response of the member to be reinforced obtained in the first measurement step and the vibration response of the reinforcing part obtained in the second measurement step are substantially the same, it is determined that the member to be reinforced and the reinforcing part are integrated. When the vibration response of the member to be reinforced obtained in the first measurement step and the vibration response of the reinforcing part obtained in the second measurement step are different, it is determined that the integration of the member to be reinforced and the reinforcing part has deteriorated. The integration evaluation method according to [7].

Advantages of the Invention

[0014] According to the present invention, it is possible to provide an integration evaluation method and an integration evaluation device capable of relatively easily confirming the integration between a member to be reinforced and a reinforcing part.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0016] 〔First Embodiment〕 Hereinafter, a first embodiment of the integrity evaluation method and the integrity evaluation apparatus according to the present invention will be described in detail with reference to the drawings. FIG. 1(a) is a perspective view of a reinforced column 1 (reinforced structure) which is the object of the integrity evaluation method of the present embodiment, and FIG. 1(b) is a perspective view showing the removal of the reinforcement part 5 from the reinforced column 1. In FIG. 1(a), the concrete part 9 of the reinforcement part 5 is shown by a broken line. FIG. 2(a) is a vertical sectional view showing an enlarged view of the vicinity of the reinforcement part 5 of the reinforced column 1, and FIG. 2(b) is a horizontal sectional view thereof.

[0017] The reinforced column 1 is a column reinforced by the winding method and is, for example, a pier of a road bridge. The reinforced column 1 is erected on the footing 2 and includes an existing column part 3 (member to be reinforced) and a reinforcement part 5 (reinforcement part) installed on the surface of the existing column part 3. The existing column part 3 is an existing column made of reinforced concrete. The reinforcement part 5 is, for example, for the purpose of seismic reinforcement of the existing column part 3 and reinforces the existing column part 3 by winding it, and is provided over the entire circumference of the existing column part 3. The reinforcement part 5 is made of reinforced concrete and has axial steel bars 7 extending in the axial direction (vertical direction) of the reinforced column 1, hoop steel bars 8 extending in the circumferential direction of the reinforced column 1, and a concrete part 9 embedding these steel bars (reinforcement materials).

[0018] Further, the reinforced column 1 is provided with a first optical fiber sensor 11 (FIG. 1(b)) installed on the existing column part 3. Although details will be described later, the first optical fiber sensor 11 functions as a sensor for measuring the vibration response or strain of the existing column part 3. The first optical fiber sensor 11 is adhered to the surface of the existing column part 3 in the region where the reinforcement part 5 is provided and expands and contracts following the expansion and contraction of the existing column part 3. Note that the first optical fiber sensor 11 is located inside the reinforcement part 5 and also contacts the concrete part 9 of the reinforcement part 5. However, the first optical fiber sensor 11 is insulated from the expansion and contraction behavior of the concrete part 9 by a predetermined process and expands and contracts following the expansion and contraction of the existing column part 3 as described above.

[0019] A plurality of first optical fiber sensors 11 may be provided on the surface of the existing column portion 3. Each of the first optical fiber sensors 11 on the surface of the existing column portion 3 may extend in the axial direction of the reinforcing column 1, or may extend in the circumferential direction of the reinforcing column 1. Also, those extending in the axial direction and those extending in the circumferential direction may be provided in combination. In the example of Fig. 1(b), three first optical fiber sensors 11 are provided on the surface of the existing column portion 3. When distinguishing these three, they are respectively called first optical fiber sensors 11a, 11b, and 11c. The first optical fiber sensor 11a extends in the axial direction of the reinforcing column 1. The first optical fiber sensors 11b and 11c extend in the circumferential direction of the reinforcing column 1 at positions with different heights from each other.

[0020] Furthermore, the reinforcing column 1 includes a second optical fiber sensor 12 (Fig. 1(a)) installed in the reinforcing portion 5. Although details will be described later, the second optical fiber sensor 12 functions as a sensor for measuring the vibration response or strain of the reinforcing portion 5. The second optical fiber sensor 12 is embedded in the concrete portion 9 in a state of being installed on the axial steel bar 7 or the strip steel bar 8, and expands and contracts following the expansion and contraction of the reinforcing portion 5. A plurality of second optical fiber sensors 12 may be provided in the reinforcing portion 5. The second optical fiber sensor 12 may extend in the axial direction of the reinforcing column 1, or may extend in the circumferential direction of the reinforcing column 1. Also, those extending in the axial direction and those extending in the circumferential direction may be provided in combination. In the example of Fig. 1(a), three second optical fiber sensors 12 are provided in the reinforcing portion 5. When distinguishing these three, they are respectively called second optical fiber sensors 12a, 12b, and 12c.

[0021] The second optical fiber sensor 12 is disposed at a position along the first optical fiber sensor 11. That is, each second optical fiber sensor 12 is positioned slightly away from the first optical fiber sensor 11 in the thickness direction of the reinforcing portion 5 and extends parallel to the first optical fiber sensor 11. More specifically, as understood from FIGS. 1 and 2, a second optical fiber sensor 12a is provided in parallel in the immediate vicinity of the first optical fiber sensor 11a, a second optical fiber sensor 12b is provided in parallel in the immediate vicinity of the first optical fiber sensor 11b, and a second optical fiber sensor 12c is provided in parallel in the immediate vicinity of the first optical fiber sensor 11c.

[0022] Note that the present invention is not limited to the example of FIG. 1, and a larger number of first optical fiber sensors 11 and second optical fiber sensors 12 may be provided. The number of stages, range, and intervals for arranging the first optical fiber sensor 11 and the second optical fiber sensor 12 can be appropriately set according to the dimensions of the existing column portion 3 and the reinforcing portion 5 and the measurement purpose.

[0023] The first optical fiber sensor 11 and the second optical fiber sensor 12 may be as shown in FIG. 3. FIG. 3 is a perspective view schematically showing the first optical fiber sensor 11 and the second optical fiber sensor 12 existing in the reinforcing column 1. In the form of FIG. 3, one optical fiber cable 13 extends on the surface of the existing column portion 3 while bending and along a path passing through each installation location of the first optical fiber sensors 11a to 11c. The first optical fiber sensors 11a, 11b, and 11c are each constituted by a part of one optical fiber cable 13. Similarly, the second optical fiber sensors 12a, 12b, and 12c are also each constituted by a part of one optical fiber cable 14.

[0024] In addition, the optical fiber cable 13 and the optical fiber cable 14 are connected in series. In this case, the optical fiber cable 13 and the optical fiber cable 14 are connected to form one optical fiber cable 15, and it can be said that all the optical fiber sensors 11a, 11b, 11c, 12a, 12b, 12c installed on the reinforcing column 1 are respectively constituted by parts of one optical fiber cable 15. One end or both ends of the optical fiber cable 15 are drawn out from the reinforcing part 5 and can be connected to a measuring instrument for vibration response measurement or strain measurement.

[0025] In the reinforcing column 1 of the present embodiment, it is assumed that the first optical fiber sensor 11 and the second optical fiber sensor 12 as described above shown in FIG. 3 are adopted.

[0026] The reinforcement work for the existing column part 3 for constructing such a reinforcing column 1 is carried out by the following first optical fiber sensor installation process, steel bar installation process, second optical fiber sensor installation process, and concrete placing process. (First optical fiber sensor installation process) First, the surface of the existing column part 3 to be reinforced is roughened, and the optical fiber cable 13 is laid and adhered while bending along a predetermined path on the surface of the existing column part 3, so that the first optical fiber sensors 11a, 11b, 11c are installed. (Steel bar installation process) Subsequently, the axial steel bars 7 and the hoop bars 8 are installed around the existing column part 3. (Second optical fiber sensor installation process) Thereafter, the optical fiber cable 14 is attached to the axial steel bars 7 and the hoop bars 8 so as to extend along the optical fiber cable 13, so that the second optical fiber sensors 12a, 12b, 12c are installed. Here, the second optical fiber sensor 12a is attached to the axial steel bar 7, and the second optical fiber sensors 12a, 12b are respectively attached to the hoop bars 8, 8 having different heights from each other. And the optical fiber cable 14 is connected in series to the optical fiber cable 13. (Concrete placing process) Thereafter, a formwork is installed so as to surround the axial reinforcement bars 7 and the stirrups 8, and the concrete portion 9 is placed.

[0027] Through such reinforcement work, a reinforced column 1 having the existing column portion 3 and the reinforcement portion 5 is constructed. In the reinforced column 1, the existing column portion 3 and the reinforcement portion 5 are integrated and behave integrally, so that the ductility and load-bearing capacity are improved as compared with the existing column portion 3. However, in this type of reinforcement work, the integrity between the existing column portion 3 and the reinforcement portion 5 may not be sufficient due to insufficient surface treatment of the existing column portion 3 or the like. Also, cracks or the like may occur during use, and the reinforcement portion 5 may peel off, resulting in a decrease in the integrity between the existing column portion 3 and the reinforcement portion 5. If the integrity between the existing column portion 3 and the reinforcement portion 5 is reduced, the reinforcement effect as designed cannot be exerted. Therefore, in order to confirm the integrity between the existing column portion 3 and the reinforcement portion 5 and to confirm the validity of the design, the integrity evaluation method of the present embodiment is implemented for the reinforced column 1.

[0028] The integrity evaluation method of the present embodiment uses the first optical fiber sensor 11 and the second optical fiber sensor 12 to evaluate the integrity between the existing column portion 3 and the reinforcement portion 5. For example, the integrity evaluation method of the present embodiment can be implemented to confirm the integrity between the existing column portion 3 and the reinforcement portion 5 after the completion of the reinforced column 1 or after an earthquake occurs. The integrity evaluation method of the present embodiment is implemented by an evaluation device 91 shown in FIG. 4. FIG. 4 is a block diagram showing the components of the evaluation device 91 and the reinforced column 1. The evaluation device 91 includes a DAS measuring instrument 21 that is detachably connected to the optical fiber cable 15 as necessary, and an arithmetic device 23 (for example, a computer) that is connected to the DAS measuring instrument 21 and performs arithmetic operations based on the information input from the DAS measuring instrument 21. The integrity evaluation method of the present embodiment includes a first measurement step, a second measurement step, an integrity determination step, and an evaluation result presentation step, which will be described below.

[0029] (First Measurement Step) As shown in FIG. 4, in the first measurement step, a DAS measuring device 21 and a computing device 23 are connected to one or both ends of the optical fiber cable 15. Then, the vibration response of the existing column part 3 is measured by DAS measurement (Distributed Acoustic Sensing) using the first optical fiber sensor 11 on the existing column part 3. DAS measurement may also be called "distributed vibration measurement method", "distributed acoustic sensing", "distributed vibration sensing", etc.

[0030] The DAS measurement is based on the following principle. Pulse light is incident from the DAS measuring device 21 on the optical fiber cable 15, and the scattered light from each part (each measurement point) in the longitudinal direction of the optical fiber cable 15 returns to the DAS measuring device 21. Since the scattered light from each measurement point of the optical fiber cable 15 changes due to the strain generated at that measurement point, by analyzing the change in the scattered light with the DAS measuring device 21, the dynamic strain of each measurement point of the optical fiber cable 15 can be known. That is, the vibration waveform of each measurement point of the optical fiber cable 15 can be known. DAS measurement may also be called "distributed vibration measurement method", "distributed acoustic sensing", "distributed vibration sensing", etc. In this embodiment, the interval between measurement points in the DAS measurement is, for example, about 0.2 m. In DAS measurement, it is possible to measure a minute strain of 1 μ or less at a high sampling frequency of about 1 kHz.

[0031] In the first measurement step, when the reinforced column 1 vibrates due to an external force applied from the outside, the vibration is transmitted to the first optical fiber sensor 11 at each measurement point P1 of the existing column portion 3, and the first optical fiber sensor 11 dynamically expands and contracts (vibrates). The external force may be, for example, an impact load intentionally applied to the reinforced column 1 by hitting it with a hammer, or may be a traffic load or the like acting on the reinforced column 1. At this time, in the DAS measuring device 21, based on the scattered light from each measurement point P1 of the first optical fiber sensor 11 on the optical fiber cable 15, the vibration response of each measurement point P1 of the first optical fiber sensor 11 is obtained. The information on the vibration response of each measurement point P1 detected by the DAS measuring device 21 is transmitted to the arithmetic unit 23. Since the vibration response of each measurement point P1 of the first optical fiber sensor 11 reflects the vibration response of the existing column portion 3 in the vicinity of the measurement point P1, in the arithmetic unit 23, the distribution of the vibration response of the existing column portion 3 along the first optical fiber sensor 11 is recognized.

[0032] (Second measurement step) In the second measurement step, the vibration response of the reinforcement portion 5 is measured by DAS measurement using the second optical fiber sensor 12 installed in the reinforcement portion 5. This second measurement step is executed simultaneously with the above-described first measurement step. Specifically, when an external force is applied to the reinforced column 1 as described above, the reinforcement portion 5 vibrates and the second optical fiber sensor 12 dynamically expands and contracts (vibrates). At this time, in the DAS measuring device 21, not only the scattered light from the first optical fiber sensor 11 on the optical fiber cable 15 but also the scattered light from each measurement point P2 of the second optical fiber sensor 12 is obtained. Therefore, in the DAS measuring device 21, based on the scattered light in the same manner as in the first measurement step, the vibration response of each measurement point P2 of the second optical fiber sensor 12 is obtained, and in the arithmetic unit 23, the distribution of the vibration response of the reinforcement portion 5 along the second optical fiber sensor 12 is recognized. Each measurement point P2 on the second optical fiber sensor 12 is set at a position immediately adjacent to each measurement point P1 on the first optical fiber sensor 11.

[0033] (Integrity judgment step) In the integrity determination step, based on the comparison between the measurement result obtained in the first measurement step and the measurement result obtained in the second measurement step by the arithmetic unit 23, the integrity between the existing column portion 3 and the reinforcement portion 5 is determined. Here, if it is assumed that the existing column portion 3 and the reinforcement portion 5 are integrated, since the existing column portion 3 and the reinforcement portion 5 behave as a unit, it is considered that the vibration responses of the existing column portion 3 and the reinforcement portion 5 to the above external force are substantially the same. And if it is assumed that the integrity between the existing column portion 3 and the reinforcement portion 5 is reduced, it is considered that the vibration responses of the existing column portion 3 and the reinforcement portion 5 to the above external force are different.

[0034] Based on this finding, in the integrity determination step, the arithmetic unit 23 compares the distribution of the vibration response of the existing column portion 3 obtained in the first measurement step and the distribution of the vibration response of the reinforcement portion 5 obtained in the second measurement step. If the vibration responses of the measurement point P1 of the existing column portion 3 and the measurement point P2 of the reinforcement portion 5 closest to it are substantially the same, the arithmetic unit 23 determines that the existing column portion 3 and the reinforcement portion 5 are integrated in the vicinity of these measurement points P1 and P2. Also, if the vibration responses of the measurement point P1 of the existing column portion 3 and the measurement point P2 of the reinforcement portion 5 closest to it are different, the arithmetic unit 23 determines that the integrity between the existing column portion 3 and the reinforcement portion 5 is reduced in the vicinity of these measurement points P1 and P2. The arithmetic unit 23 executes the above comparison and determination for each pair of measurement points P1 and P2. Note that the above "vibration responses are substantially the same" means that the amplitudes and frequencies of the waveforms of the vibration responses to be compared are substantially the same. That is, "vibration responses are substantially the same" means that the difference or ratio between the amplitudes of the vibration response waveforms to be compared is equal to or less than a predetermined value, and the difference or ratio between the frequencies is equal to or less than a predetermined value. Alternatively, whether the "vibration responses are substantially the same" may be determined by a comprehensive judgment considering the amplitudes, frequencies, etc. of the waveforms of the vibration responses to be compared.

[0035] (Evaluation result presentation step) By performing the integrity determination as described above between each pair of measurement points P1 and P2, the arithmetic unit 23 recognizes the distribution of the integrity between the existing column portion 3 and the reinforcing portion 5 along the first optical fiber sensor 11 and the second optical fiber sensor 12. The arithmetic unit 23 may visualize the information on the integrity distribution state thus obtained and display it on a screen of a display device or the like provided in the arithmetic unit 23 as an evaluation result of the integrity between the existing column portion 3 and the reinforcing portion 5 and present it to the user.

[0036] In the integrity evaluation method of the present embodiment described above, if a DAS measuring instrument 21 or the like is connected to the optical fiber cable 15 installed in the reinforcing column 1, the integrity between the existing column portion 3 and the reinforcing portion 5 of the reinforcing column 1 can be confirmed. Therefore, compared with other inspections using various sensors, devices, systems, etc., for example, the integrity between the existing column portion 3 and the reinforcing portion 5 can be easily confirmed after the construction of the reinforcing column 1 or after an earthquake occurs. Also, it is more economical compared to other inspections and maintenance management is relatively easy.

[0037] 〔Second Embodiment〕 Subsequently, the integrity evaluation method according to the second embodiment will be described in detail. In this embodiment, in the reinforcement work of the existing column portion 3 for constructing the reinforcing column 1, the following pre-reinforcement measurement process is executed. Also, the integrity determination process in the integrity evaluation method of the present embodiment is different from that of the first embodiment as described later. Regarding the same points as those in the first embodiment in the present embodiment, redundant explanations will be omitted.

[0038] (Pre-reinforcement Measurement Process) The pre-reinforcement measurement process is executed after the above-described first optical fiber sensor installation process and before the concrete placement process. The pre-reinforcement measurement process measures the vibration response or strain of the existing column portion 3 using the first optical fiber sensor 11 before the reinforcing portion 5 is constructed. Specifically, in the step of installing the first optical fiber sensor, the DAS measuring instrument 21 and the computing device 23 are connected to the optical fiber cable 13 installed on the existing column portion 3, and DAS measurement is performed in the same manner as in the above-described first measurement step. Here, in the computing device 23, the distribution of the vibration response of the existing column portion 3 before reinforcement along the first optical fiber sensor 11 is recognized. The distribution of the vibration response of the existing column portion 3 before reinforcement obtained here is stored in the storage unit of the computing device 23.

[0039] After that, when the integrity evaluation method of the present embodiment is implemented after the completion of the reinforced column 1, the first measurement step and the second measurement step are executed in the same manner as in the first embodiment. The integrity determination step executed after the first measurement step and the second measurement step is as follows.

[0040] (Integrity determination step) In the integrity determination step of the present embodiment, the integrity between the existing column portion 3 and the reinforcement portion 5 is determined based on a comparison between the measurement result obtained in the first measurement step and the measurement result obtained in the pre-reinforcement measurement step. Here, when the existing column portion 3 is appropriately reinforced by the reinforcement portion 5, it is considered that the bending rigidity increases compared to before reinforcement, and accordingly, the vibration characteristics of the existing column portion 3 also change. That is, assuming that the existing column portion 3 and the reinforcement portion 5 are integrated, it is considered that the vibration response of the existing column portion 3 to an external force changes compared to before the construction of the reinforcement portion 5. Specifically, it is considered that the frequency of the vibration waveform increases and the amplitude decreases compared to before the construction of the reinforcement portion 5. Further, assuming that the integrity between the existing column portion 3 and the reinforcement portion 5 is insufficient, it is considered that the changes in the frequency and amplitude as described above are small.

[0041] Based on this finding, in the integrity determination process, the arithmetic unit 23 compares the distribution of the vibration response of the existing column part 3 after reinforcement obtained in the first measurement process with the distribution of the vibration response of the existing column part 3 before reinforcement obtained in the pre-reinforcement measurement process and stored in the storage unit of the arithmetic unit 23. Then, when there is an increase in frequency and a decrease in amplitude of more than a predetermined amount between the vibration waveforms before and after reinforcement at the same measurement point P1, the arithmetic unit 23 determines that the existing column part 3 and the reinforcement part 5 are integrated in the vicinity of this measurement point P1. Also, when there is no increase in frequency and a decrease in amplitude of more than a predetermined amount between the vibration waveforms before and after reinforcement at the same measurement point P1, the arithmetic unit 23 determines that the integrity between the existing column part 3 and the reinforcement part 5 is insufficient in the vicinity of this measurement point P1. Alternatively, it may be determined whether the existing column part 3 and the reinforcement part 5 are integrated by a comprehensive determination considering the amplitude, frequency, etc. of the compared vibration waveforms. By the arithmetic unit 23, the above-described comparison and determination are executed at each measurement point P1, and the distribution of the integrity between the existing column part 3 and the reinforcement part 5 along the first optical fiber sensor 11 is recognized.

[0042] Also, according to the integrity evaluation method of the present embodiment described above, similar to the first embodiment, it is possible to easily confirm the integrity between the existing column part 3 and the reinforcement part 5 after the construction of the reinforced column 1 or the like. And it is possible to know whether the reinforcement work of the existing column part 3 was appropriate. In the present embodiment, the second measurement process may be omitted. Also, in the present embodiment, the second optical fiber sensor installation process in the reinforcement work of the existing column part 3 may be omitted, that is, the second optical fiber sensor 12 in the reinforced column 1 may be omitted.

[0043] 〔Third Embodiment〕 Next, the integrity evaluation method according to the third embodiment will be described in detail. In the integrity evaluation method of this embodiment, in addition to the integrity evaluation method of the first embodiment, the first measurement step is also executed at the start of service after the completion of the reinforcing column 1. Here, in the arithmetic unit 23, the distribution of the vibration response of the existing column portion 3 at the start of service along the first optical fiber sensor 11 is recognized. The distribution of the vibration response of the existing column portion 3 at the start of service obtained here is stored in the storage unit of the arithmetic unit 23. Also, the integrity determination step in the integrity evaluation method of this embodiment is different from that of the first embodiment as will be described later. Regarding the same points as in the first embodiment in this embodiment, overlapping explanations will be omitted.

[0044] For example, when the integrity evaluation method of this embodiment is implemented after an earthquake occurs in the reinforcing column 1, the first measurement step and the second measurement step are executed in the same manner as in the first embodiment. The integrity determination step executed thereafter is as follows.

[0045] (Integrity determination step) In the integrity determination step of this embodiment, the integrity between the existing column portion 3 and the reinforcing portion 5 is determined based on a comparison between the measurement result obtained in the first measurement step at the current time (when the integrity evaluation method is implemented) and the measurement result obtained in the first measurement step at the start of service of the reinforcing column 1. Here, if it is assumed that the integrity between the existing column portion 3 and the reinforcing portion 5 has decreased between the start of service and the current time, it is considered that the bending rigidity of the reinforcing column 1 has decreased due to this, and as a result, the vibration characteristics of the existing column portion 3 also change. Specifically, it is considered that due to the decrease in the integrity between the existing column portion 3 and the reinforcing portion 5, the frequency of the vibration waveforms of the existing column portion 3 and the reinforcing portion 5 decreases and the amplitude increases.

[0046] Based on this finding, in the integrity determination step, the arithmetic unit 23 compares the distribution of the vibration response of the existing column portion 3 at the current time obtained in the first measurement step with the distribution of the vibration response of the existing column portion 3 at the start of service stored in the storage unit of the arithmetic unit 23. Then, if the vibration responses at the same measurement point P1 at the current time and at the start of service are substantially the same, the arithmetic unit 23 determines that the existing column portion 3 and the reinforcement portion 5 are integrated in the vicinity of this measurement point P1. Also, if the vibration responses at the same measurement point P1 at the current time and at the start of service are different, the arithmetic unit 23 determines that the integrity between the existing column portion 3 and the reinforcement portion 5 has deteriorated in the vicinity of this measurement point P1. By the arithmetic unit 23, the above-described comparison and determination are executed at each measurement point P1, and the distribution of the integrity between the existing column portion 3 and the reinforcement portion 5 along the first optical fiber sensor 11 is recognized. Note that the meaning of "the vibration responses are substantially the same" may be the same as the meaning in the integrity determination step of the first embodiment described above.

[0047] Also, according to the integrity evaluation method of the present embodiment described above, similar to the first embodiment, for example, the integrity between the existing column portion 3 and the reinforcement portion 5 can be easily confirmed after an earthquake occurs in the reinforced column 1. In the present embodiment, the second measurement step may be omitted. Also, in the present embodiment, the second optical fiber sensor installation step in the reinforcement work of the existing column portion 3 may be omitted, that is, the second optical fiber sensor 12 in the reinforced column 1 may be omitted.

[0048] In addition, in this embodiment, the vibration response of the existing column portion 3 using the first optical fiber sensor 11 is measured at the start of service and at the current time, but this may be replaced with the measurement of the vibration response of the reinforcement portion 5 using the second optical fiber sensor 12. That is, in this embodiment, the integrity between the existing column portion 3 and the reinforcement portion 5 may be determined based on the comparison between the distribution of the vibration response of the reinforcement portion 5 obtained in the second measurement step at the current time and the distribution of the vibration response of the reinforcement portion 5 obtained in the second measurement step performed at the start of service. In this case, the first measurement step may be omitted. Also in this case, the first optical fiber sensor installation step in the reinforcement work of the existing column portion 3 may be omitted, that is, the first optical fiber sensor 11 in the reinforced column 1 may be omitted.

[0049] In this embodiment, the distribution of the vibration response of the existing column portion 3 at the current time and the distribution of the vibration response of the existing column portion 3 at the start of service are compared, but it is not limited to this. For example, based on the comparison between the distribution of the vibration response of the existing column portion 3 measured before the earthquake and the distribution of the vibration response of the existing column portion 3 at the current time after the earthquake, the integrity evaluation method of this embodiment after the earthquake may be implemented.

[0050] 〔Fourth Embodiment〕 Subsequently, the integrity evaluation method according to the fourth embodiment will be described in detail. In the integrity evaluation method of this embodiment, the strain distribution measurement of the existing column portion 3 using the first optical fiber sensor 11 is performed in the first measurement step, and the strain distribution measurement of the reinforcement portion 5 using the second optical fiber sensor 12 is performed in the second measurement step. Also, the integrity determination step in the integrity evaluation method of this embodiment is different from that of the first embodiment as described later. Duplicate explanations for the same points as in the first embodiment in this embodiment are omitted.

[0051] (First Measurement Step) In the first measurement step of this embodiment, instead of the aforementioned DAS measuring instrument 21, a strain measuring instrument (not shown) is connected to the optical fiber cable 15. Then, based on the result of strain measurement using the first optical fiber sensor 11 as a strain sensor, the distribution of the vertical strain of the existing column portion 3 in the horizontal cross-section is acquired. For example, here, as shown in FIG. 5(a), on each of the two side surfaces parallel to the Y direction on the surface of the existing column portion 3 having a rectangular cross-section, the first optical fiber sensors 11, 11 extending in the Z direction (vertical direction) are installed. Based on the strain measured by this pair of first optical fiber sensors 11, 11, in the arithmetic unit 23, as shown in FIG. 5(b), the linear distribution 33 of the Z strain of the existing column portion 3 in the X direction is acquired.

[0052] (Second measurement step) In the second measurement step of this embodiment, in the same manner as in the first measurement step, based on the result of strain measurement using the pair of second optical fiber sensors 12, 12 as strain sensors, the distribution of the Z strain of the reinforcement portion 5 in the horizontal cross-section is acquired. For example, here, as shown in FIG. 5(c), the linear distribution 35 of the Z strain of the reinforcement portion 5 in the X direction is acquired.

[0053] (Integrity determination step) In the integrity determination step, the arithmetic unit 23 determines the integrity between the existing column portion 3 and the reinforcement portion 5 based on a comparison between the measurement result obtained in the first measurement step and the measurement result obtained in the second measurement step. Here, if it is assumed that the existing column portion 3 and the reinforcement portion 5 are integrated, since the existing column portion 3 and the reinforcement portion 5 behave as a single entity, as shown in FIG. 5(d), it is considered that the strain distribution 33 of the existing column portion 3 and the strain distribution 35 of the reinforcement portion 5 coincide and are continuous. And if it is assumed that the integrity between the existing column portion 3 and the reinforcement portion 5 is reduced, as shown in FIG. 5(e), it is considered that the strain distribution 33 and the strain distribution 35 become discontinuous at the boundary portion between the existing column portion 3 and the reinforcement portion 5.

[0054] Based on this finding, when the strain distribution 33 of the existing column part 3 obtained in the first measurement step and the strain distribution 35 of the reinforcement part 5 obtained in the second measurement step are continuous, the arithmetic unit 23 determines that the existing column part 3 and the reinforcement part 5 are integrated within this horizontal cross-section. Further, when the strain distribution 33 and the strain distribution 35 are discontinuous, the arithmetic unit 23 determines that the integrity between the existing column part 3 and the reinforcement part 5 has decreased within this horizontal cross-section. In the arithmetic unit 23, by performing the above-described comparison and determination for each horizontal cross-section including each measurement point P1, P2, the distribution of the integrity between the existing column part 3 and the reinforcement part 5 is recognized.

[0055] Also, according to the integrity evaluation method of the present embodiment described above, similar to the first embodiment, for example, it is possible to easily confirm the integrity between the existing column part 3 and the reinforcement part 5 after the construction of the reinforced column 1 or after an earthquake occurs.

[0056] The present invention can be implemented in various forms with various changes and improvements based on the knowledge of those skilled in the art, starting from the above-described embodiments. Also, it is possible to configure the following modification examples by using the technical matters described in the above-described embodiments. The configurations of each embodiment etc. may be used in appropriate combination.

[0057] For example, the integrity evaluation method of the present invention is not limited to the winding method and can also be applied to a reinforced column reinforced by a cross-section repair method. As an example of a reinforced column by a cross-section repair method, a reinforced column 51 is shown in FIG. 6(a). The reinforced column 51 includes an existing column part 53 (member to be reinforced) formed by chipping off a part of the cover concrete of an existing reinforced concrete column, and a reinforcement part 55 made of high-strength concrete (for example, ultra-high-strength fiber-reinforced concrete (UFC)) placed in the part where the cover concrete has been chipped off. According to such a cross-section repair method, it is possible to improve the deformation performance without increasing the cross-sectional dimensions and self-weight of the reinforced column 51.

[0058] Further, a crack-inducing joint 57 is embedded in the reinforcing portion 55. The crack-inducing joint 57 is composed of a pair of angle members 58, 58 with their outer surfaces in close contact. The angle members 58, 58 are each fixed to the existing column portion 53 with an anchor (not shown), and the outer surfaces of the angle members 58, 58 are not joined. The tip portions of the angle members 58, 58 are exposed on the side surface of the reinforcing column 51. When excessive bending deformation occurs in the reinforcing column 51, cracks are induced by the expansion of the distance between the angle members 58, 58.

[0059] In the reinforcement work for the existing column portion 53 for constructing the reinforcing column 51, the first optical fiber sensor 11 is adhered to the exposed surface of the existing column portion 53 where the cover concrete has been chiseled off. Also, a second optical fiber sensor 12 is attached to the angle member 58, and the second optical fiber sensor 12 is embedded in the high-strength concrete of the reinforcing portion 55. When reinforcing bars are installed in the reinforcing portion 55, the second optical fiber sensor 12 may be attached to the reinforcing bars. In such a reinforcing column 51, when evaluating the integrity between the existing column portion 53 and the reinforcing portion 55, the integrity evaluation method of the present invention can be applied following the integrity evaluation methods in the first to fourth embodiments.

[0060] Further, for example, the integrity evaluation method of the present invention can also be applied to a reinforcing column reinforced by the steel plate erection method. In the steel plate erection method, as shown in FIG. 6(b), a steel plate 64 is arranged around the existing column portion 3, and a curable filling material 65 (for example, non-shrink mortar, epoxy resin, etc.) is filled in the gap between the existing column portion 3 and the steel plate 64. In this case, when no reinforcing bars are installed in the reinforcing portion, the second optical fiber sensor 12 may be attached to the inner surface of the steel plate 64. Also, the integrity evaluation method of the present invention can be applied to a reinforcing column reinforced by the PC erection method, the precast panel erection method, the fiber sheet erection method, etc.

[0061] In addition, although the vibration response measurement in each of the above-described embodiments is performed by DAS measurement, it is not limited thereto. For example, if strain measurement can be performed at a sampling frequency of several Hz to 100 Hz, vibration response measurement may be performed by other optical fiber measurement methods (e.g., FBG-OFDR). Further, the present invention can also be applied to the integrity evaluation for repair and reinforcement by surface repair or thickening of the floor slab as well as reinforcement of the column member.

[0062] In the first to third embodiments described above, the judgment material for judging the integrity between the member to be reinforced and the reinforcing portion is the vibration response of each portion measured using the optical fiber sensors 11 and 12. Instead of this, the strain of each portion measured using the optical fiber sensors 11 and 12 may be used as the judgment material. In this case, the strain measurement of each portion using the optical fiber sensors 11 and 12 may be performed in the same manner as the first and second measurement steps described in the fourth embodiment. Further, comprehensive judgment may be made using both the vibration response and the strain of each portion measured using the optical fiber sensors 11 and 12 as the judgment material. That is, in the integrity judgment step in the first to third embodiments, not only the comparison result of the vibration response but also the comparison result of the strain may be taken into consideration and the integrity may be comprehensively judged.

Explanation of Reference Numerals

[0063] 1... Reinforced column (reinforcing structure), 3... Existing column portion (member to be reinforced), 5... Reinforcing portion, 7... Axial reinforcement (reinforcement), 8... Stirrup (reinforcement), 11, 11a, 11b, 11c... First optical fiber sensor (optical fiber sensor), 12, 12a, 12b, 12c... Second optical fiber sensor, 21... DAS measuring device (vibration response measuring portion), 23... Arithmetic device (arithmetic portion), 91... Evaluation device (integrity evaluation device).

Claims

1. An integrality evaluation method for evaluating the integrality between a member to be reinforced and a reinforcing part provided on the surface of the member to be reinforced so as to be integrated with the member to be reinforced, comprising: a measuring step of measuring the vibration response and / or strain of the site where the optical fiber sensor is installed by using the optical fiber sensor installed on the member to be reinforced or the reinforcing part; an integrality determination step of determining the integrality based on the measurement result obtained in the measuring step.

2. In the measuring step, the vibration response and / or strain of the member to be reinforced are measured by using the optical fiber sensor installed on the member to be reinforced, further comprising a second measuring step of measuring the vibration response and / or strain of the reinforcing part by using a second optical fiber sensor installed on the reinforcing part and extending along the optical fiber sensor; In the integrality determination step, the integrality is determined based on a comparison between the measurement result obtained in the measuring step and the measurement result obtained in the second measuring step. The integrality evaluation method according to Claim 1.

3. a first optical fiber sensor installation step of installing the optical fiber sensor on the surface of the member to be reinforced in a reinforcement work of constructing the reinforced structure by reinforcing the member to be reinforced with the reinforcing part; a second optical fiber sensor installation step of installing the second optical fiber sensor on a reinforcing material embedded in the reinforcing part in the reinforcement work. The integrality evaluation method according to Claim 2.

4. In the measuring step, the vibration response and / or strain of the member to be reinforced are measured by using the optical fiber sensor installed on the member to be reinforced, In the integrality determination step, the integrality is determined based on a comparison between the measurement result obtained in the measuring step and the measurement result of the vibration response and / or strain of the member to be reinforced before reinforcement measured in advance by using the optical fiber sensor before the reinforcing part is constructed. The integrality evaluation method according to Claim 1.

5. In the integrality determination step, the integrality is determined based on a comparison between the measurement result obtained in the measuring step and the measurement result of the vibration response and / or strain measured by using the optical fiber sensor in the past. The integrality evaluation method according to Claim 1.

6. In a reinforcing structure including a member to be reinforced and a reinforcing portion installed on the surface of the member to be reinforced so as to be integrated with the member to be reinforced, an integrality evaluation apparatus for evaluating the integrality between the member to be reinforced and the reinforcing portion, a vibration response measurement unit that is connected to a first optical fiber sensor installed on the member to be reinforced and measures the vibration response of the member to be reinforced using the first optical fiber sensor, and that is connected to a second optical fiber sensor installed on the reinforcing portion and measures the vibration response of the reinforcing portion using the second optical fiber sensor; an integrality evaluation apparatus including an arithmetic unit that determines the integrality based on a comparison between the vibration response of the member to be reinforced and the vibration response of the reinforcing portion obtained from the vibration response measurement unit.

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