Determination method, determination device, and program

Abstract

A determination method according to the present disclosure is executed by a determination device (1) that determines the necessity of repair of a reinforced concrete structure (2), which comprises reinforcing bars (21) and concrete (22) covering the reinforcing bars (21), and which defines an interior space (IS). The determination method includes: a stress degree calculation step for calculating a deterioration stress strain relationship indicating a correspondence relationship between stress degree and strain of a deteriorated reinforced concrete structure (2-B), using a deterioration model representing a deteriorated reinforced concrete structure, which is a reinforced concrete structure from which a concrete cover on the interior space (IS) side has peeled off; and a determination step for determining whether or not repair of the reinforced concrete structure is necessary, on the basis of the deterioration stress strain relationship and an assumed stress level (fw) that is expected to occur in the environment where the reinforced concrete structure (2) is installed.

Description

Technical Field

[0001] The present disclosure relates to a determination method, a determination device, and a program.

Background Art

[0002] Conventionally, manholes made of reinforced concrete (RC) are known to deteriorate. The deterioration of manholes includes external forces, alkali-silica reaction (ASR) (see Non-Patent Document 1), poor concrete material or poor construction, or concrete peeling and cracking due to progress of carbonation or reinforcement corrosion caused by salt damage.

[0003] Such deterioration of manholes is generally confirmed by visually observing cracks, concrete peeling, exposed reinforcement, etc. Further, it is also known that the deterioration of manholes is monitored by methods using strain gauges (see Non-Patent Document 2), methods using optical fiber sensors (see Non-Patent Document 3), and methods for electrochemically detecting reinforcement corrosion (see Non-Patent Document 4), etc.

[0004] In addition, the criteria and timing for repairing concrete structures such as manholes are determined by the administrator of the concrete structure, and the administrator repairs the concrete so as to prevent the progress of corrosion of the reinforcement contained in the concrete structure. For example, in order to repair a concrete structure, it is known to perform surface coating, cathodic protection, etc. according to deterioration factors, deterioration states, etc. (see Non-Patent Document 5).

[0005] Furthermore, since the deterioration sites, sizes, and types (cracks, concrete peeling, reinforcement exposure, etc.) differ for each concrete structure, it is also known to perform structural analysis individually (see Non-Patent Document 6).

Prior Art Documents

Non-Patent Documents

[0006]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

Non-Patent Document 6

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, reinforced concrete structures such as manholes are expected to deteriorate and are designed based on a safety factor to maintain their integrity even after a certain degree of deterioration. Therefore, even if cracks or spalling occur in the concrete due to external forces, ASR, or defects in the concrete material or construction, if the remaining load-bearing capacity is sufficient when considering the predetermined safety factor, prompt repair may not be necessary. In contrast, if repairs are carried out each time cracks or spalling are confirmed in the concrete using the aforementioned technology, without load-bearing capacity assessment through structural analysis, it becomes difficult to control the management costs required to maintain the safety of reinforced concrete structures. Furthermore, if cracks or spalling are confirmed and structural analysis is performed, using the design drawings used when the reinforced concrete structure was constructed makes it difficult to appropriately assess the current deterioration of the reinforced concrete structure.

[0008] Furthermore, as mentioned above, technologies that individually determine whether or not repairs are necessary for structures have difficulty comprehensively determining whether or not repairs are necessary for structures in various conditions. As a result, the processing load becomes high, making it difficult to efficiently determine whether or not repairs are necessary for structures.

[0009] In view of these circumstances, the purpose of this disclosure is to provide a determination method, determination device, and program that can efficiently determine whether or not repairs are necessary for reinforced concrete structures, while suppressing management costs for maintaining the safety of reinforced concrete structures. [Means for solving the problem]

[0010] To solve the above problems, the determination method according to the present disclosure is a determination method performed by a determination device for determining whether or not to repair a reinforced concrete structure comprising reinforcing bars and concrete covering the reinforcing bars, which defines an internal space, and includes a stress calculation step of calculating a deterioration stress-strain relationship showing the correspondence between stress and strain of the deteriorated reinforced concrete structure using a deterioration model representing the deteriorated reinforced concrete structure, which is the reinforced concrete structure in which the concrete cover on a predetermined surface on the internal space side has peeled off; and a determination step of determining whether or not to repair the reinforced concrete structure based on the deterioration stress-strain relationship and assumed stress that is expected to occur in the environment in which the reinforced concrete structure is installed.

[0011] Furthermore, in order to solve the above problems, the determination device according to the present disclosure is a determination device for determining whether or not repair is necessary for a reinforced concrete structure that defines an internal space, comprising reinforcing bars and concrete covering the reinforcing bars, and comprising: a stress calculation unit that calculates a deterioration stress-strain relationship showing the correspondence between stress and strain of the deteriorated reinforced concrete structure using a deterioration model that represents a deteriorated reinforced concrete structure in which the concrete cover on a predetermined surface on the internal space side has peeled off; and a determination unit that determines whether or not repair is necessary for the reinforced concrete structure based on the deterioration stress-strain relationship and assumed stress that is expected to occur in the environment in which the reinforced concrete structure is installed.

[0012] Furthermore, in order to solve the above-mentioned problems, the program relating to this disclosure causes a computer to execute the degradation determination method described above. [Effects of the Invention]

[0013] The determination method, determination device, and program described herein make it possible to efficiently determine whether or not repairs are necessary for reinforced concrete structures while suppressing management costs for maintaining the safety of reinforced concrete structures. [Brief explanation of the drawing]

[0014] [Figure 1] This is a schematic perspective view showing an example of a determination device according to the first embodiment of this disclosure. [Figure 2A] Figure 1 is a schematic diagram showing an example of a reinforced concrete structure in which a determination device determines whether or not repairs are necessary. [Figure 2B] Figure 2A is a cross-sectional view of a reinforced concrete structure. [Figure 2C] Figure 2B is a magnified view of a portion of the reinforced concrete structure shown. [Figure 3A] This figure shows an example of a sound, deteriorated reinforced concrete structure. [Figure 3B] This figure shows an example of a deteriorated reinforced concrete structure. [Figure 4] This figure shows the stress-strain curves for a sound, deteriorated reinforced concrete structure and a deteriorated reinforced concrete structure, respectively. [Figure 5] Figure 1 is a flowchart showing an example of the operation performed by the determination device. [Figure 6] This is a schematic diagram showing an example of a determination device according to the second embodiment of this disclosure. [Figure 7] Figure 6 is a flowchart showing an example of the operation performed by the determination device. [Figure 8] Figure 1 shows an example of the hardware configuration of the judgment device. [Modes for carrying out the invention]

[0015] <<First Embodiment>> <Configuration of the judgment device> The determination device 1 of the first embodiment will be described with reference to Figure 1. Figure 1 is a schematic diagram showing an example of the determination device 1 according to the first embodiment.

[0016] The determination device 1, as shown in Figures 2A and 2B, comprises reinforcing bars 2a and concrete 2b covering the reinforcing bars 2a, and determines whether or not repairs are necessary for the reinforced concrete structure 2 that defines the internal space IS.

[0017] In this example, the reinforced concrete structure 2 defines the internal space IS by an upper member 21, a side member 22, and a lower member 23. For example, the upper member 21 is the upper floor slab, the side member 22 is the side wall, and the lower member 23 is the lower floor slab. Furthermore, the upper member 21 has a hole HL defined for people to enter and exit the internal space IS. The upper member 21, side member 22, and lower member 23 are each composed of reinforcing bars 2a and concrete 2b covering the reinforcing bars 2a (in Figure 2B, the reinforcing bars 2a are shown on the upper member 21). Also, as shown in Figure 2C, cracks 2c and spalling 2d may occur in the concrete 2b of the reinforced concrete structure 2, and the spalling 2d may become large enough to expose the reinforcement 2e. In this example, the reinforced concrete structure 2 is a rectangular parallelepiped, but this is not limited to this.

[0018] There are multiple standards for reinforced concrete structures 2, and the size of the reinforced concrete structures 2 differs for each standard. Furthermore, reinforced concrete structures 2 in some standards are similar in shape to each other. For example, in the case where the reinforced concrete structure 2 is a manhole, a manhole of one standard, straight type 1 (S-1), and a manhole of another standard, straight type 2 (S-2), are similar in shape to each other.

[0019] As shown in Figure 1, the determination device 1 comprises an input unit 11, a stress calculation unit 12, a determination unit 13, and an output unit 14. The input unit 11 is configured by an input interface. The input interface may be a communication interface. For example, standards such as Ethernet®, FDDI (Fiber Distributed Data Interface), and Wi-Fi® may be used for the communication interface. The stress calculation unit 12 and the determination unit 13 are configured by a controller. The controller may be configured by dedicated hardware such as an ASIC (Application Specific Integrated Circuit) or FPGA (Field-Programmable Gate Array), or by a processor, or by including both. The output unit 14 is configured by an output interface. The output interface may be a communication interface.

[0020] The input unit 11 receives input of rust stain information relating to rust stains or rust stains on the reinforced concrete structure 2. The rust stain information may also be information indicating whether or not there are rust stains or rust stains on the reinforced concrete structure 2. For example, the rust stain information may be information based on observations by an inspector, stored in an inspection device including a database, and input from the inspection device to the input unit 11. Alternatively, the rust stain information may be image information showing an image of the reinforced concrete structure 2 captured by an imaging device such as a camera, and input from the imaging device to the input unit 11.

[0021] The stress calculation unit 12 uses a deterioration model representing deteriorated reinforced concrete structure 2-B (see Figure 3B), which is a reinforced concrete structure 2 in which the concrete cover has been peeled off on a predetermined surface on the internal space IS side, to calculate the deterioration stress-strain relationship showing the correspondence between stress and strain in deteriorated reinforced concrete structure 2-B. In deteriorated reinforced concrete structure 2-B, the concrete cover has been peeled off over the entire surface on a predetermined surface on the internal space IS side. In the example shown in Figure 3B, the predetermined surface is the surface of the upper member 21.

[0022] The deterioration model is a model (see Figure 3B) that represents a deteriorated reinforced concrete structure 2-B, in which the concrete cover on a predetermined surface on the internal space IS side of one surface member (for example, the upper surface member 21) has peeled off, compared to a sound reinforced concrete structure 2-A, which is a reinforced concrete structure 2 in which no deterioration has occurred, as shown in Figure 3A. The deterioration model can be a solid model.

[0023] Here, the stress calculation unit 12 will be described in detail. As shown in Figure 1, the stress calculation unit 12 includes a cover element number setting unit 121, a finite element model construction unit 122, a finite element analysis unit 123, and a calculation unit 124.

[0024] The cover element setting unit 121 sets the size and number of meshes for constructing a deterioration model using the finite element method. Specifically, as shown in Figure 3B, the cover element setting unit 121 sets the size and number of meshes that can be set using the finite element method so that the length of the concrete peeling of concrete 2b is maximized in the range where the concrete cover on a predetermined surface on the internal space IS side of the reinforced concrete structure 2 is peeled off and the reinforcing bars 2a are not exposed. For example, the cover element setting unit 121 sets the size and number of meshes so that the length Ly (see Figure 2C) of the peeled concrete 2b in the direction normal to the surface of the upper surface member 21 is shorter than the length d (see Figure 2C) from the surface on the internal space IS side of the upper surface member 21 to the reinforcing bars 2a, and is the maximum value that can be set using the finite element method.

[0025] The finite element model construction unit 122 can construct a deterioration model using the finite element method with a mesh of the size and number determined by the cover element number setting unit 121. Since the cover element number setting unit 121 sets the mesh size and number as described above, the finite element model construction unit 122 can construct a deterioration model representing the deteriorated reinforced concrete structure 2-B in which the concrete cover on a predetermined surface on the internal space IS side of the reinforced concrete structure 2-B is peeled off, and the length of the peeled concrete 2b is the longest in the area where the reinforcement 2a is not exposed. As a result, the finite element model construction unit 122 can construct a deterioration model that comprehensively represents the reinforced concrete structure 2 in various deterioration states of varying magnitudes in the early stages of the deterioration process caused by corrosion, external forces, etc.

[0026] Furthermore, the finite element model construction unit 122 may construct a sound model representing the sound reinforced concrete structure 2-A using the finite element method.

[0027] The finite element analysis unit 123 uses a deterioration model to calculate a deterioration stress-strain relationship showing the correspondence between stress and strain in a deteriorated reinforced concrete structure 2-B. Alternatively, the finite element analysis unit 123 may use a sound model to calculate a sound stress-strain relationship showing the correspondence between stress and strain in a sound reinforced concrete structure 2-A.

[0028] The stress-strain relationship in degraded structures and the stress-strain relationship in sound structures may be represented by stress-strain curves, as shown in Figure 4. Figure 4 shows the design value X of stress for sound reinforced concrete structure 2-A. A , and the design value X of the stress of deteriorated reinforced concrete structure 2-B B This is shown. The design value for stress is the maximum stress in the range where stress and strain have a roughly linear relationship. Roughly linear means that the rate of change of stress with respect to strain (the slope of the curve shown in Figure 4) is roughly constant (the rate of change is below a threshold).

[0029] The calculation unit 124 calculates the design value X of the stress of deteriorated reinforced concrete structure 2-B, which is shown by the deterioration stress-strain relationship.B Based on the stress level and the safety factor α, the allowable stress f of the deteriorated reinforced concrete structure 2-B is calculated. The safety factor α is the ratio of the allowable stress to the breaking stress in the materials used for the reinforced concrete structure 2, and is a value greater than 1 determined when designing the reinforced concrete structure 2. Specifically, the calculation unit 124 calculates the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. Bα Based on the stress level and the safety factor α, the allowable stress f of the deteriorated reinforced concrete structure 2-B is calculated. The safety factor α is the ratio of the allowable stress to the breaking stress in the materials used for the reinforced concrete structure 2, and is a value greater than 1 determined when designing the reinforced concrete structure 2. Specifically, the calculation unit 124 calculates the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. B Based on the stress level and the safety factor α, the allowable stress f of the deteriorated reinforced concrete structure 2-B is calculated. The safety factor α is the ratio of the allowable stress to the breaking stress in the materials used for the reinforced concrete structure 2, and is a value greater than 1 determined when designing the reinforced concrete structure 2. Specifically, the calculation unit 124 calculates the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. Bα Based on the stress level and the safety factor α, the allowable stress f of the deteriorated reinforced concrete structure 2-B is calculated. The safety factor α is the ratio of the allowable stress to the breaking stress in the materials used for the reinforced concrete structure 2, and is a value greater than 1 determined when designing the reinforced concrete structure 2. Specifically, the calculation unit 124 calculates the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. B2 Based on the stress level and the safety factor α, the allowable stress f of the deteriorated reinforced concrete structure 2-B is calculated. The safety factor α is the ratio of the allowable stress to the breaking stress in the materials used for the reinforced concrete structure 2, and is a value greater than 1 determined when designing the reinforced concrete structure 2. Specifically, the calculation unit 124 calculates the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. B3 Based on the stress level and the safety factor α, the allowable stress f of the deteriorated reinforced concrete structure 2-B is calculated. The safety factor α is the ratio of the allowable stress to the breaking stress in the materials used for the reinforced concrete structure 2, and is a value greater than 1 determined when designing the reinforced concrete structure 2. Specifically, the calculation unit 124 calculates the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively.

[0030] Furthermore, the calculation unit 124 may calculate the allowable stress f of the sound reinforced concrete structure 2-A represented by the sound model based on the design value X of the stress level of the sound reinforced concrete structure 2-A shown by the sound stress-strain relationship and the safety factor α. Specifically, the calculation unit 124 may calculate the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. A Furthermore, the calculation unit 124 may calculate the allowable stress f of the sound reinforced concrete structure 2-A represented by the sound model based on the design value X of the stress level of the sound reinforced concrete structure 2-A shown by the sound stress-strain relationship and the safety factor α. Specifically, the calculation unit 124 may calculate the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. Aα Furthermore, the calculation unit 124 may calculate the allowable stress f of the sound reinforced concrete structure 2-A represented by the sound model based on the design value X of the stress level of the sound reinforced concrete structure 2-A shown by the sound stress-strain relationship and the safety factor α. Specifically, the calculation unit 124 may calculate the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. A Furthermore, the calculation unit 124 may calculate the allowable stress f of the sound reinforced concrete structure 2-A represented by the sound model based on the design value X of the stress level of the sound reinforced concrete structure 2-A shown by the sound stress-strain relationship and the safety factor α. Specifically, the calculation unit 124 may calculate the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. Aα Furthermore, the calculation unit 124 may calculate the allowable stress f of the sound reinforced concrete structure 2-A represented by the sound model based on the design value X of the stress level of the sound reinforced concrete structure 2-A shown by the sound stress-strain relationship and the safety factor α. Specifically, the calculation unit 124 may calculate the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. A2 Furthermore, the calculation unit 124 may calculate the allowable stress f of the sound reinforced concrete structure 2-A represented by the sound model based on the design value X of the stress level of the sound reinforced concrete structure 2-A shown by the sound stress-strain relationship and the safety factor α. Specifically, the calculation unit 124 may calculate the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively. A3 Furthermore, the calculation unit 124 may calculate the allowable stress f of the sound reinforced concrete structure 2-A represented by the sound model based on the design value X of the stress level of the sound reinforced concrete structure 2-A shown by the sound stress-strain relationship and the safety factor α. Specifically, the calculation unit 124 may calculate the value obtained by dividing the design value X of the stress level by the safety factor α as the allowable stress f. In FIG. 4, as an example, the allowable stress f when the safety factor α is 2, and the allowable stress f when the safety factor α is 3 are shown respectively.

[0031] The determination unit 13 may determine whether repair of the reinforced concrete structure 2 is necessary based on the rust juice information. If there is rust juice or rust juice marks on the reinforced concrete structure 2, the reinforcing bar 2a is exposed, and therefore, it is expected that the deterioration is progressing. On the other hand, if there is no rust juice or rust juice marks on the reinforced concrete structure 2, the reinforcing bar 2a is not exposed to the atmosphere, and therefore, it is expected that the deterioration may not be progressing. <00​​Therefore, the determination unit 13 may determine whether or not there is rust stain or rust stain on the reinforced concrete structure. If the determination unit 13 determines that there is rust stain or rust stain on the reinforced concrete structure, it may determine that repair of the reinforced concrete structure 2 is necessary. If the determination unit 13 determines that there is no rust stain or rust stain on the reinforced concrete structure 2, it may determine the deterioration stress-strain relationship and the assumed stress f, as will be explained in detail below. w Based on this, it may be determined whether or not repairs to reinforced concrete structure 2 are necessary.

[0033] The determination unit 13 determines the relationship between deterioration stress and strain, and the assumed stress f that is expected to occur in the environment in which the reinforced concrete structure 2 is installed. w Based on this, it is determined whether or not repairs are necessary for reinforced concrete structure 2.

[0034] Specifically, the determination unit 13 determines the design value X of the stress of the deteriorated reinforced concrete structure 2-B, which is shown in the deterioration stress-strain relationship. B The allowable stress f is obtained by dividing this by the safety factor α of the reinforced concrete structure. Bα However, the assumed stress f that is expected to occur in an environment where reinforced concrete structure 2 is installed w The determination unit 13 determines whether or not the allowable stress f Bα The assumed stress f w If it is determined that the above is true, it is determined that repair of the reinforced concrete structure 2 is not necessary. In addition, the determination unit 13 determines the allowable stress f Bα The assumed stress f w If it is determined to be less than [a certain value], it is determined that repairs to reinforced concrete structure 2 are necessary.

[0035] As described above, in a configuration where rust stain information is image information showing an image of the reinforced concrete structure 2, the determination unit 13 determines whether or not there is rust stain or rust stain on the reinforced concrete structure 2 based on the image information. Specifically, if the determination unit 13 detects an image of rust stain or rust stain within the image of the reinforced concrete structure 2 using arbitrary image processing, it determines that there is rust stain or rust stain on the reinforced concrete structure 2. Conversely, if the determination unit 13 does not detect an image of rust stain or rust stain within the image of the reinforced concrete structure 2 using the same image processing, it determines that there is no rust stain or rust stain on the reinforced concrete structure 2.

[0036] The output unit 14 outputs the determination result determined by the determination unit 13. For example, the output unit 14 may display the determination result on a display device configured as an integral part of or separately from the determination device 1. Alternatively, the output unit 14 may output the determination result to another device via a communication network, or it may output the determination result by any method such as voice.

[0037] <Operation of the Judgment Device> Here, the operation of the determination device 1 according to the first embodiment will be described with reference to Figure 5. Figure 5 is a flowchart showing an example of the operation of the determination device 1 according to the first embodiment. The operation of the determination device 1 described with reference to Figure 5 corresponds to an example of the determination method executed by the determination device 1 according to the first embodiment.

[0038] In step S11, the input unit 11 receives input of rust stain information relating to rust stains or rust stain traces on the reinforced concrete structure 2 (input step).

[0039] In step S12, the determination unit 13 determines, based on the rust stain information, whether or not there is rust stain or rust stain on the reinforced concrete structure 2 (determination step).

[0040] If, in step S12, it is determined that there is rust stain or rust stain on the reinforced concrete structure 2, then in step 16, the determination unit 13 determines that repair of the reinforced concrete structure 2 is necessary (determination step).

[0041] If, in step 12, it is determined that there is no rust stain or rust stain on the reinforced concrete structure 2, then in step S13, the stress calculation unit 12 calculates the deterioration stress-strain relationship (stress calculation step), and in steps S14 to S16, the determination unit 13 determines the deterioration stress-strain relationship and the assumed stress f w Based on this, it is determined whether or not repairs are necessary for reinforced concrete structure 2 (determination step).

[0042] Specifically, in step S13, the stress calculation unit 12 calculates a deterioration stress-strain relationship showing the correspondence between stress and strain of deteriorated reinforced concrete structure 2-B, which is a deteriorated reinforced concrete structure 2 in which the concrete cover has peeled off on a predetermined surface on the internal space IS side (stress calculation step). At this time, the stress calculation unit 12 determines the size and number of meshes for constructing the deterioration model by the finite element method, and can construct the deterioration model by the finite element method using the meshes of the specified size and number.

[0043] In step S14, the determination unit 13 determines the design value X of the stress of the deteriorated reinforced concrete structure 2-B, which is shown by the deterioration stress-strain relationship. B The allowable stress f is obtained by dividing this by the safety factor α of the reinforced concrete structure 2. Bα The assumed stress f w Determine whether or not the value is greater than or equal to the above (determination step).

[0044] In step S14, the allowable stress f Bα The assumed stress f w If it is determined that the above conditions are met, in step S15, the determination unit 13 determines that repair of the reinforced concrete structure 2 is not necessary (determination step).

[0045] In step S14, the allowable stress f Bα The assumed stress f wIf it is determined that the value is less than the specified value, in step S16, the determination unit 13 determines that the reinforced concrete structure 2 requires repair (determination step).

[0046] In step S17, the output unit 14 outputs the determination result (output step).

[0047] As described above, the determination method according to the first embodiment is a determination method executed by a determination device 1 that determines whether or not repair is necessary for a reinforced concrete structure 2 comprising reinforcing bars 2a and concrete 2b covering the reinforcing bars 2a, which defines an internal space IS. Furthermore, the determination method according to the first embodiment includes a stress calculation step that uses a deterioration model representing a deteriorated reinforced concrete structure 2-B, which is a reinforced concrete structure 2 in which the concrete cover on a predetermined surface on the internal space IS side has peeled off, to calculate a deterioration stress-strain relationship showing the correspondence between stress and strain of the deteriorated reinforced concrete structure 2-B, and the deterioration stress-strain relationship and the assumed stress f that is assumed to occur in the environment in which the reinforced concrete structure 2 is installed. w The method includes a determination step of determining whether or not repairs are necessary for the reinforced concrete structure 2 based on the above.

[0048] This allows for an accurate determination of whether or not repairs are necessary for reinforced concrete structure 2. Therefore, even if cracks or other damage are visually detected, repairs to reinforced concrete structure 2 that still possesses the necessary structural strength can be postponed. Consequently, management costs for maintaining the safety of reinforced concrete structures can be reduced.

[0049] Furthermore, if structural analysis were performed using a model that reflects the actual deterioration state of reinforced concrete structure 2, the processing load would increase, making it difficult to make an efficient determination. In contrast, in the determination method according to the first embodiment, the deterioration model can comprehensively represent reinforced concrete structures in various deterioration states, so it is possible to efficiently determine whether or not repairs are necessary for the reinforced concrete structure.

[0050] Furthermore, the determination method according to the first embodiment further includes an input step for receiving input of rust stain information relating to rust stains or rust stains on the reinforced concrete structure 2. The determination step determines, based on the rust stain information, whether or not there are rust stains or rust stains on the reinforced concrete structure 2. If it is determined that there are rust stains or rust stains on the reinforced concrete structure 2, it is determined that repair of the reinforced concrete structure 2 is necessary. If it is determined that there are no rust stains or rust stains on the reinforced concrete structure 2, it is determined that the deterioration stress-strain relationship and the assumed stress f w The method includes a step of determining whether or not repairs are necessary for the reinforced concrete structure 2 based on the above. Thus, according to the determination method of the first embodiment, repairs can be carried out immediately for reinforced concrete structures 2 that are determined to have rust stains and rust stains without performing a determination using the stress-strain relationship, and the processing load can be reduced because a determination using the stress-strain relationship is performed for reinforced concrete structures 2 that are determined to have no rust stains and rust stains.

[0051] <<Second Embodiment>> <Configuration of the judgment device> The determination device 1-1 of the second embodiment will be described with reference to Figure 6. Figure 6 is a schematic diagram showing an example of the determination device 1-1 according to this embodiment. In the second embodiment, the same reference numerals are used for functional parts that are the same as in the first embodiment, and their descriptions are omitted.

[0052] The determination device 1-1 comprises an input unit 11, a stress calculation unit 12-1, a determination unit 13-1, and an output unit 14. The stress calculation unit 12-1 and the determination unit 13-1 are configured by a controller.

[0053] The stress calculation unit 12-1 includes a cover element number setting unit 121, a finite element model construction unit 122, a finite element analysis unit 123-1, a calculation unit 124-1, and a deterioration ratio calculation unit 125.

[0054] The finite element analysis unit 123-1 uses a deterioration model representing the deteriorated reinforced concrete structure 2-B of the first standard, which is a reinforced concrete structure 2 of the first standard, where the concrete cover has peeled off on a predetermined surface on the internal space IS side, to calculate the deterioration stress-strain relationship showing the correspondence between stress and strain of the deteriorated reinforced concrete structure 2-B of the first standard. This process corresponds to the process by which the finite element analysis unit 123-1 calculates the deterioration stress-strain relationship in the first embodiment described above. In other words, the deteriorated reinforced concrete structure in the first embodiment is the deteriorated reinforced concrete structure of the first standard in the second embodiment.

[0055] Furthermore, the finite element analysis unit 123-1 uses a sound model representing a sound reinforced concrete structure 2-A of the first standard, which is a reinforced concrete structure 2 of the first standard that has not deteriorated, to calculate a first sound stress-strain relationship that shows the correspondence between stress and strain in the sound reinforced concrete structure 2-A of the first standard.

[0056] The deterioration ratio calculation unit 125 calculates the deterioration ratio β. The deterioration ratio β is the design value X of the stress of a sound reinforced concrete structure 2-A of the first standard, as shown by the first sound stress-strain relationship. A The design value X of stress for deteriorated reinforced concrete structure 2-B of the first standard, as shown by the deterioration stress-strain relationship. B This is the ratio.

[0057] Furthermore, the finite element analysis unit 123-1 uses a sound model representing a sound reinforced concrete structure 2-A of the second standard, which is similar in shape to the first standard but different in size, to calculate a second sound stress-strain relationship that shows the correspondence between stress and strain in a sound reinforced concrete structure 2-A of the second standard.

[0058] Furthermore, the calculation unit 124-1 calculates the allowable stress f of a sound reinforced concrete structure 2-A of the second standard, based on the second sound stress-strain relationship. A’α The value obtained by multiplying by the deterioration ratio β is the allowable stress f for deteriorated reinforced concrete structures 2-B of the second standard. B’αThe calculation is performed as follows: Here, the calculation unit 124-1 calculates the design value X of the stress of a reinforced concrete structure of the second standard, as shown by the second sound stress-strain relationship. A’ The allowable stress f is obtained by dividing this value by the safety factor α of the reinforced concrete structure 2. A’α It can be calculated as follows.

[0059] The determination unit 13-1 determines the allowable stress f of the deteriorated reinforced concrete structure 2-B of the second standard. B’α However, the assumed stress f w’ Based on whether or not the above conditions are met, it is determined, in the same manner as in the first embodiment, whether or not repair of the reinforced concrete structure 2 conforming to the second standard is necessary.

[0060] Specifically, the determination unit 13-1 determines the allowable stress f of the deteriorated reinforced concrete structure 2-B of the second standard. B’α However, the assumed stress f that is expected to occur in an environment where a reinforced concrete structure of the second standard 2 is installed w’ The determination unit 13-1 then determines whether the value is greater than or equal to the above. B’α The assumed stress f w’ If it is determined that the above is true, it is determined that repair of the reinforced concrete structure 2 of the second standard is not necessary. The determination unit 13-1 is the allowable stress f B’α The assumed stress f w’ If it is determined to be less than the specified value, it is determined that repairs to the reinforced concrete structure 2 of the second standard are necessary.

[0061] Furthermore, the stress calculation unit 12-1 can similarly calculate the allowable stress of a deteriorated reinforced concrete structure 2-B of a k-th standard (where k is an integer of 3 or more) that is similar in shape to the first and second standards but differs in size, based on the deterioration ratio β. In this case, the determination unit 13-1 can similarly determine whether or not repair is necessary for the reinforced concrete structure 2 of the k-th standard.

[0062] Generally, due to dimensional effects, reinforced concrete structures 2 are more likely to fail at a lower strength than expected as their size increases. For this reason, the representative model representing the deteriorated reinforced concrete structure 2-B of the first standard is preferably the model representing the deteriorated reinforced concrete structure 2-B of the standard with the largest size. In this configuration, the deterioration stress-strain relationship of reinforced concrete structures 2 of the standard with a smaller size than the reinforced concrete structure 2 represented by the representative model is calculated using the deterioration ratio β, as described above. In this way, by using the largest-sized structure, which is most likely to have low strength, as the representative model, it becomes possible to safely evaluate (evaluate for a state that is less likely to become dangerous) the concrete structure 2 represented by each model.

[0063] <Operation of the Judgment Device> Here, the operation of the determination device 1-1 according to the second embodiment will be described with reference to Figure 7. Figure 7 is a flowchart showing an example of the operation of the determination device 1-1 according to the second embodiment. The operation of the determination device 1-1 described with reference to Figure 7 corresponds to an example of the determination method of the determination device 1-1 according to the second embodiment, which determines whether or not repair is necessary for a reinforced concrete structure 2 comprising reinforcing bars 2a and concrete 2b covering the reinforcing bars 2a, and defining an internal space IS.

[0064] The operation in which the determination device 1-1 performs a determination on the reinforced concrete structure 2 conforming to the first standard is the same as the operation of the determination device 1 in the first embodiment, as described with reference to Figure 5. Hereafter, the operation in which the determination device 1-1 performs a determination on the reinforced concrete structure 2 conforming to the second standard will be described.

[0065] In step S21, the stress calculation unit 12-1 uses a sound model representing a sound reinforced concrete structure 2-A, which is a first-standard reinforced concrete structure that has not deteriorated, to calculate a first sound stress-strain relationship showing the correspondence between stress and strain of the first-standard sound reinforced concrete structure 2-A. This operation corresponds to the operation in step S13 in the first embodiment described above. Therefore, after the operation of the first embodiment has been performed, the operation in step S21 does not need to be performed.

[0066] In step S22, the stress calculation unit 12-1 uses a sound model representing a sound reinforced concrete structure 2-A, which is a first standard reinforced concrete structure that has not deteriorated, to calculate a first sound stress-strain relationship that shows the correspondence between stress and strain of the first standard sound reinforced concrete structure 2-A (stress calculation step).

[0067] In step S23, the deterioration ratio calculation unit 125 calculates the design value X of the stress of a sound reinforced concrete structure 2-A of the first standard, as shown by the first sound stress-strain relationship. A The design value X of stress for deteriorated reinforced concrete structure 2-B of the first standard, as shown by the deterioration stress-strain relationship. B The degradation ratio β, which is the ratio of (degradation ratio calculation step), is calculated.

[0068] In step 24, the input unit 11 receives input of rust stain information relating to rust stains or rust stain traces of the reinforced concrete structure 2 conforming to the second standard (input step).

[0069] In step S25, the determination unit 13-1 determines, based on the rust stain information, whether or not there is rust stain or rust stain marks on the reinforced concrete structure conforming to the second standard (determination step).

[0070] If, in step S25, it is determined that there is rust stain or rust stain on the reinforced concrete structure conforming to the second standard, then in step 31, the determination unit 13-1 determines that repair of the reinforced concrete structure 2 conforming to the second standard is necessary (determination step).

[0071] If, in step 25, it is determined that there is no rust stain or rust stain on the reinforced concrete structure conforming to the second standard, then in step S26, the stress calculation unit 12-1 calculates the deterioration stress-strain relationship (stress calculation step), and in steps S27 to S31, the determination unit 13-1 determines the deterioration stress-strain relationship and the assumed stress f w Based on this, it is determined whether or not repairs are necessary for the reinforced concrete structure 2 of the second standard (determination step).

[0072] Specifically, in step S26, the stress calculation unit 12-1 uses a sound model representing a sound reinforced concrete structure 2-A of the second standard, which is similar in shape to the first standard but different in size, to calculate a second sound stress-strain relationship showing the correspondence between stress and strain of the sound reinforced concrete structure 2-A of the second standard (stress calculation step).

[0073] Then, the stress calculation unit 12-1 calculates the allowable stress f of a sound reinforced concrete structure 2-A of the second standard, based on the sound stress-strain relationship of the second standard. A’α The value obtained by multiplying this by the deterioration ratio β is the allowable stress f for deteriorated reinforced concrete structure 2-B of the second standard. B’α This is calculated as (stress calculation step).

[0074] Specifically, in step S27, the stress calculation unit 12-1 calculates the design value X of the stress. A’ The allowable stress f is the value obtained by dividing this by the safety factor α. A’α This is calculated as (stress calculation step).

[0075] In step S28, the stress calculation unit 12-1 calculates the allowable stress f A’α The value obtained by multiplying by the deterioration ratio β is the allowable stress f for deteriorated reinforced concrete structures 2-B of the second standard. B’αThis is calculated as (stress calculation step).

[0076] In step S29, the determination unit 13-1 determines the allowable stress f of the deteriorated reinforced concrete structure 2-B of the second standard. B’α However, the assumed stress f that is expected to occur in an environment where a reinforced concrete structure of the second standard 2 is installed w’ Determine whether or not the value is greater than or equal to the above (determination step).

[0077] In step S29, the allowable stress f B’α The assumed stress f w’ If it is determined that the above conditions are met, in step S30, the determination unit 13-1 determines that repair of the reinforced concrete structure 2 conforming to the second standard is not necessary (determination step).

[0078] In step S29, the allowable stress f B’α The assumed stress f w’ If it is determined that the value is less than the specified value, in step S31, the determination unit 13-1 determines that repair of the reinforced concrete structure conforming to the second standard is necessary (determination step).

[0079] In step S32, the output unit 14 outputs the determination result (output step).

[0080] In addition, in the operation described above, the determination device 1-1 may use the deterioration ratio β calculated in step S23 to repeatedly execute the processes from step S24 onward to determine whether or not repair is necessary for the deteriorated reinforced concrete structure 2-B of the kth standard (where k is an integer of 3 or more). In this case, the determination device 1-1 does not need to repeatedly execute the processes from step S21 to step S23 described above.

[0081] As described above, the determination method according to the second embodiment further includes a deterioration ratio calculation step. The stress calculation step also includes a step of calculating a first sound stress-strain relationship that shows the correspondence between stress and strain of the sound reinforced concrete structure 2-A of the first standard, using a sound model that represents a sound reinforced concrete structure 2-A which is a first standard reinforced concrete structure 2 in which no deterioration has occurred. Furthermore, the deterioration ratio calculation step includes a step of calculating the design value X of the stress of the sound reinforced concrete structure 2-A of the first standard, as shown by the first sound stress-strain relationship. A The design value X of stress for deteriorated reinforced concrete structure 2-B of the first standard, as shown by the deterioration stress-strain relationship. B The process includes a step to calculate the deterioration ratio β, which is the ratio of the stress. The stress calculation step also includes calculating the second sound stress-strain relationship using a sound model representing a sound reinforced concrete structure 2-A of the second standard, which is similar in shape to the first standard but different in size, and calculating the allowable stress f of the sound reinforced concrete structure 2-A of the second standard based on the sound stress-strain relationship of the second standard. A’α The value obtained by multiplying by the deterioration ratio β is the allowable stress f for deteriorated reinforced concrete structures 2-B of the second standard. B’α This includes a step to calculate the allowable stress f of deteriorated reinforced concrete structure 2-B of the second standard. B’α However, the assumed stress f that is expected to occur in an environment where a reinforced concrete structure conforming to the second standard is installed w The procedure includes a step of determining whether or not the above is true. This allows the determination device 1-1 to determine the allowable stress f by performing structural analysis using a degradation model. B’α Compared to calculating the allowable stress f of deteriorated reinforced concrete structure 2-B of the second standard, it is easier to calculate the allowable stress f B’α Since it can be calculated, the processing load on the determination device 1-1 is reduced.

[0082] <Program> The determination device 1 and determination device 1-1 described above can each be implemented by a computer 301. A program may also be provided to cause the computer 301 to function as the determination device 1 or determination device 1-1. This program may be stored on a storage medium or provided via a network. Figure 8 is a block diagram showing the schematic configuration of a computer 301 functioning as determination device 1. The schematic configuration of a computer functioning as determination device 1-1 is similar. Here, computer 301 may be a general-purpose computer, a dedicated computer, a workstation, a PC (Personal Computer), an electronic notepad, etc. Program instructions may be program code, code segments, etc., for executing the required tasks.

[0083] As shown in Figure 8, the computer 301 comprises a processor 310, a ROM (Read Only Memory) 320, a RAM (Random Access Memory) 330, storage 340, an input unit 350, an output unit 360, and a communication interface (I / F) 370. Each component is connected to the others via a bus 380 so as to be able to communicate with each other. The processor 310 is specifically a CPU (Central Processing Unit), MPU (Micro Processing Unit), GPU (Graphics Processing Unit), DSP (Digital Signal Processor), SoC (System on a Chip), etc., and may be composed of multiple processors of the same or different types.

[0084] The processor 310 controls each component and performs various arithmetic operations. Specifically, the processor 310 reads a program from the ROM 320 or storage 340 and executes the program using the RAM 330 as a working area. The processor 310 controls each component and performs various arithmetic operations according to the program stored in the ROM 320 or storage 340. In the embodiment described above, the program according to this disclosure is stored in the ROM 320 or storage 340.

[0085] The program may be stored on a storage medium readable by computer 301. Using such a storage medium, the program can be installed on computer 301. Here, the storage medium on which the program is stored may be a non-transitory storage medium. The non-transitory storage medium is not particularly limited, but may include, for example, a CD-ROM, DVD-ROM, or USB (Universal Serial Bus) memory. Alternatively, the program may be downloaded from an external device via a network.

[0086] ROM320 stores various programs and data. RAM330 temporarily stores programs or data as a working area. Storage340 consists of an HDD (Hard Disk Drive) or SSD (Solid State Drive) and stores various programs and data, including the operating system.

[0087] The input unit 350 is an interface for receiving information, and the output unit 360 is an interface for outputting information.

[0088] The communication interface 370 is an interface for communicating with external devices.

[0089] The following additional information is disclosed regarding the embodiments described above. [Additional note 1] A determination method performed by a determination device for determining whether or not a reinforced concrete structure comprising reinforcing bars and concrete covering the reinforcing bars, which defines an internal space, requires repair, A stress calculation step to calculate a deterioration stress-strain relationship showing the correspondence between stress and strain of the deteriorated reinforced concrete structure, using a deterioration model that represents the deteriorated reinforced concrete structure in which the concrete cover on a predetermined surface on the internal space side has peeled off, A determination step of determining whether or not repair of the reinforced concrete structure is necessary, based on the aforementioned stress-strain relationship of deterioration and the assumed stress expected to occur in the environment in which the reinforced concrete structure is installed. A determination method that includes this. [Additional note 2] The method further includes an input step for receiving input of rust stain information relating to rust stains or rust stains on the reinforced concrete structure, The determination method according to Appendix 1, wherein the determination step includes determining whether or not there is rust stain or rust stain on the reinforced concrete structure based on the rust stain information, determining that repair of the reinforced concrete structure is necessary if it is determined that there is rust stain or rust stain on the reinforced concrete structure, and determining whether or not repair of the reinforced concrete structure is necessary based on the deterioration stress-strain relationship and the assumed stress if it is determined that there is no rust stain or rust stain on the reinforced concrete structure. [Additional note 3] The determination method according to Appendix 1 or 2, which includes the steps of determining whether the allowable stress, obtained by dividing the design value of the stress of the deteriorated reinforced concrete structure shown in the deterioration stress-strain relationship by the safety factor of the reinforced concrete structure, is greater than or equal to the assumed stress expected to occur in the environment in which the reinforced concrete structure is installed; determining that if the allowable stress is greater than or equal to the assumed stress, it is determined that repair of the reinforced concrete structure is not necessary; and determining that if the allowable stress is less than the assumed stress, it is determined that repair of the reinforced concrete structure is necessary. [Additional note 4] The aforementioned deteriorated reinforced concrete structure is a deteriorated reinforced concrete structure conforming to the first standard, Further including a step for calculating the degradation ratio, The stress calculation step includes a step of calculating a first sound stress-strain relationship showing the correspondence between stress and strain of the sound reinforced concrete structure of the first standard, using a sound model representing a sound reinforced concrete structure of the first standard that has not deteriorated, The deterioration ratio calculation step includes calculating a deterioration ratio which is the ratio of the design value of the stress of a deteriorated reinforced concrete structure according to the first standard, as shown by the deteriorated stress-strain relationship, to the design value of the stress of a sound reinforced concrete structure according to the first standard, as shown by the first sound stress-strain relationship. The stress calculation step includes a step of using a sound model representing a sound reinforced concrete structure of a second standard, which is similar in shape to the first standard but different in size, to calculate a second sound stress-strain relationship showing the correspondence between stress and strain of a sound reinforced concrete structure of the second standard, and calculating the allowable stress of the deteriorated reinforced concrete structure of the second standard by multiplying the allowable stress of the sound reinforced concrete structure of the second standard, based on the sound stress-strain relationship of the second standard, by the deterioration ratio, as the allowable stress of the deteriorated reinforced concrete structure of the second standard. The determination method according to any one of the appendices 1 to 3, wherein the determination step includes determining whether the allowable stress of the deteriorated reinforced concrete structure according to the second standard is equal to or greater than the assumed stress that is expected to occur in the environment in which the reinforced concrete structure according to the second standard is installed. [Additional note 5] The stress calculation step described above is: A step of determining the size and number of meshes for constructing the degradation model using the finite element method, The steps include constructing the degradation model using the finite element method with the aforementioned size and number of meshes, The determination method described in any one of the appendices 1 to 4, further including the method described in any one of appendices 1 to 4. [Additional note 6] A determination device for determining whether or not repair is necessary for a reinforced concrete structure that defines an internal space, comprising reinforcing bars and concrete covering the reinforcing bars, The controller is equipped with a controller, Using a deterioration model representing a deteriorated reinforced concrete structure in which the concrete cover on a predetermined surface on the internal space side has peeled off, the deterioration stress-strain relationship showing the correspondence between stress and strain of the deteriorated reinforced concrete structure is calculated. A determination device that determines whether or not repair of the reinforced concrete structure is necessary, based on the aforementioned stress-strain relationship of deterioration and the assumed stress expected to occur in the environment in which the reinforced concrete structure is installed. [Additional note 7] 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 execute the determination method described in any one of the appendices 1 to 5.

[0090] All documents, patent applications, and technologies described herein are incorporated by reference to the same extent as if each individual document, patent application, and technology were specifically and individually described as being incorporated by reference.

[0091] 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. [Explanation of Symbols]

[0092] 1, 1-1 Judgment device 2. Reinforced concrete structures 2-A Sound reinforced concrete structure 2-B Deteriorated reinforced concrete structures 2a Reinforcement bars 2b Concrete 2c crack 2D peeling 2e exposed muscle 11 Input section 12, 12-1 Stress Calculation Section 13, 13-1 Judgment section 14 Output section 21 Upper surface member 22 Side members 23 Bottom member 121 Setting section for the number of overlapping elements 122 Finite Element Model Construction Section 123, 123-1 Finite element analysis department 124, 124-1 Calculation section 125 Degradation ratio calculation unit 301 Computer 310 Processor 320 ROM 330 RAM 340 storage 350 Input section 360 Output section 370 Communication Interfaces 380 bus

Claims

1. A determination method performed by a determination device for determining whether or not a reinforced concrete structure comprising reinforcing bars and concrete covering the reinforcing bars, which defines an internal space, requires repair, A stress calculation step to calculate a deterioration stress-strain relationship showing the correspondence between stress and strain of the deteriorated reinforced concrete structure, using a deterioration model that represents the deteriorated reinforced concrete structure in which the concrete cover on a predetermined surface on the internal space side has peeled off, A determination step of determining whether or not repair of the reinforced concrete structure is necessary, based on the aforementioned stress-strain relationship of deterioration and the assumed stress expected to occur in the environment in which the reinforced concrete structure is installed. A determination method that includes this.

2. The method further includes an input step for receiving input of rust stain information relating to rust stains or rust stains on the reinforced concrete structure, The determination method according to claim 1, wherein the determination step includes determining whether or not there is rust stain or rust stain on the reinforced concrete structure based on the rust stain information, determining that repair of the reinforced concrete structure is necessary if it is determined that there is rust stain or rust stain on the reinforced concrete structure, and determining whether or not repair of the reinforced concrete structure is necessary based on the deterioration stress-strain relationship and the assumed stress if it is determined that there is no rust stain or rust stain on the reinforced concrete structure.

3. The determination method according to claim 1 or 2, further comprising the steps of: determining whether the allowable stress obtained by dividing the design value of the stress of the deteriorated reinforced concrete structure, as shown in the deterioration stress-strain relationship, by the safety factor of the reinforced concrete structure is greater than or equal to the assumed stress expected to occur in the environment in which the reinforced concrete structure is installed; determining that repair of the reinforced concrete structure is not necessary if the allowable stress is determined to be greater than or equal to the assumed stress; and determining that repair of the reinforced concrete structure is necessary if the allowable stress is determined to be less than the assumed stress.

4. The aforementioned deteriorated reinforced concrete structure is a deteriorated reinforced concrete structure conforming to the first standard, Further including a step for calculating the degradation ratio, The stress calculation step includes a step of calculating a first sound stress-strain relationship showing the correspondence between stress and strain of the sound reinforced concrete structure of the first standard, using a sound model representing a sound reinforced concrete structure of the first standard that has not deteriorated, The deterioration ratio calculation step includes calculating a deterioration ratio which is the ratio of the design value of the stress of a deteriorated reinforced concrete structure according to the first standard, as shown by the deteriorated stress-strain relationship, to the design value of the stress of a sound reinforced concrete structure according to the first standard, as shown by the first sound stress-strain relationship. The stress calculation step includes a step of using a sound model representing a sound reinforced concrete structure of a second standard, which is similar in shape to the first standard but different in size, to calculate a second sound stress-strain relationship showing the correspondence between stress and strain of a sound reinforced concrete structure of the second standard, and calculating the allowable stress of the deteriorated reinforced concrete structure of the second standard by multiplying the allowable stress of the sound reinforced concrete structure of the second standard, based on the sound stress-strain relationship of the second standard, by the deterioration ratio, as the allowable stress of the deteriorated reinforced concrete structure of the second standard. The determination method according to claim 1 or 2, wherein the determination step includes determining whether the allowable stress of the deteriorated reinforced concrete structure according to the second standard is equal to or greater than the assumed stress that is expected to occur in the environment in which the reinforced concrete structure according to the second standard is installed.

5. The stress calculation step described above is: A step of determining the size and number of meshes for constructing the degradation model using the finite element method, The steps include constructing the degradation model using the finite element method with the aforementioned size and number of meshes, The determination method according to claim 1 or 2, further comprising:

6. A determination device for determining whether or not repair is necessary for a reinforced concrete structure that defines an internal space, comprising reinforcing bars and concrete covering the reinforcing bars, A stress calculation unit calculates a deterioration stress-strain relationship showing the correspondence between stress and strain of a deteriorated reinforced concrete structure, using a deterioration model that represents a deteriorated reinforced concrete structure in which the concrete cover on a predetermined surface on the internal space side has been peeled off. A determination unit that determines whether or not repair of the reinforced concrete structure is necessary based on the aforementioned stress-strain relationship of deterioration and the assumed stress expected to occur in the environment in which the reinforced concrete structure is installed, A determination device equipped with the following features.

7. A program for causing a computer to execute the determination method described in claim 1 or 2.

Images