Expansion joint monitoring system, expansion joint monitoring device, expansion joint monitoring method, and program

Abstract

To enable monitoring of the fatigue life of expandable pipe joints regardless of the magnitude of expansion or contraction. [Solution] In the control unit 11 of the management server 10 that constitutes the expansion joint monitoring system, the information acquisition unit 111 acquires deformation information regarding the deformation of the expandable pipe joints that connect the pipes, the stress calculation unit 113 calculates the stress of the pipe joints from the acquired deformation information, the damage degree calculation unit 114 calculates the degree of damage accumulated in the pipe joints from the history of the calculated stress of the pipe joints, and the lifespan calculation unit 115 calculates the fatigue life of the pipe joints from the calculated degree of damage.

Description

[Technical Field]

[0001] The present invention relates to an expansion joint monitoring system, an expansion joint monitoring device, an expansion joint monitoring method, and a program. [Background technology]

[0002] A technique is known for calculating the remaining lifespan of a bellows-type expansion joint, which is a flexible pipe joint that absorbs expansion and contraction and deformation caused by temperature changes in overhead pipes such as gas pipes, thereby reducing thermal stress on the overhead pipes (see Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Patent No. 3782863 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Conventional technology calculates the remaining lifespan of a bellows-type expansion joint from the number of expansions and contractions. Therefore, if the magnitude of expansion and contraction is not constant, the accuracy of the remaining lifespan calculation decreases. Furthermore, because the number of expansions and contractions is counted based on a predetermined magnitude of expansion and contraction, the accuracy of the remaining lifespan calculation also decreases if small expansions and contractions that do not reach the count are repeated.

[0005] The objective of this invention is to enable monitoring of the fatigue life of an expandable pipe joint regardless of the magnitude of expansion or contraction of the pipe joint. [Means for solving the problem]

[0006] The invention described in claim 1 is an expansion joint monitoring system comprising: an acquisition means for acquiring deformation information relating to the deformation of an expandable pipe joint connecting pipes; a stress calculation means for calculating the stress of the pipe joint from the acquired deformation information; a damage degree calculation means for calculating the degree of accumulated damage to the pipe joint from the calculated stress history; and a life calculation means for calculating the fatigue life of the pipe joint from the calculated degree of damage. The invention described in claim 2 is an expansion joint monitoring system according to claim 1, wherein the acquisition means acquires the amount of deformation of the pipe joint in the pipe axis direction, measured by a displacement meter installed on the pipe joint, as deformation information. The invention described in claim 3 is the expansion joint monitoring system according to claim 2, wherein the displacement meter is installed at a plurality of positions in the circumferential direction of the pipe joint. The invention described in claim 4 is an expansion joint monitoring system according to claim 2, wherein the acquisition means acquires temperature information relating to the temperature of the pipe joint measured by a thermometer installed near the displacement meter, and the stress calculation means calculates thermal stress as the stress of the pipe joint based on the deformation information relating to the displacement of the pipe joint due to the thermal expansion of the pipe and the temperature information. The invention described in claim 5 is the expansion joint monitoring system according to claim 1, wherein the pipe joint is a bridge-mounted bellows type expansion joint that connects the pipes capable of supplying gas. The invention described in claim 6 is an expansion joint monitoring device comprising: an acquisition means for acquiring deformation information relating to the deformation of an expandable pipe joint connecting pipes; a stress calculation means for calculating the stress of the pipe joint from the acquired deformation information; a damage degree calculation means for calculating the degree of accumulated damage to the pipe joint from the calculated stress history; and a life calculation means for calculating the fatigue life of the pipe joint from the calculated degree of damage. The invention described in claim 7 is an expansion joint monitoring method comprising the steps of: acquiring deformation information relating to the deformation of an expandable pipe joint connecting pipes; calculating the stress of the pipe joint from the acquired deformation information; calculating the degree of accumulated damage to the pipe joint from the calculated stress history; and calculating the fatigue life of the pipe joint from the calculated degree of damage. The invention described in claim 8 is a program for a computer to implement control processing that includes a function to acquire deformation information relating to the deformation of an expandable pipe joint connecting pipes; a function to calculate the stress of the pipe joint from the acquired deformation information; a function to calculate the degree of accumulated damage to the pipe joint from the calculated stress history; and a function to calculate the fatigue life of the pipe joint from the calculated degree of damage. [Effects of the Invention]

[0007] According to the present invention, the fatigue life of an expandable pipe joint can be monitored regardless of the magnitude of expansion or contraction of the pipe joint. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows an example of the external configuration of a bellows-type expansion joint, which is a pipe fitting subject to monitoring. [Figure 2] (A) and (B) are conceptual diagrams illustrating the expansion and contraction of the bellows-type expansion joint in Figure 1. [Figure 3] Figures (A) through (C) show specific examples of a bellows cover installed on a bellows-type expansion joint, and measuring devices, displacement gauges, and thermometers installed on the bellows cover. [Figure 4] This figure shows an example of the overall configuration of the expansion joint monitoring system to which this embodiment is applied. [Figure 5] This figure shows an example of the hardware configuration of the management server that makes up the expansion joint monitoring system shown in Figure 4. [Figure 6] This figure shows an example of the functional configuration of the control unit of the management server shown in Figure 5. [Figure 7]It is a flowchart showing an example of the processing flow of the management server. [Figure 8] It is a conceptual diagram showing a specific example of the positional relationship of a combination of a measuring device, a displacement meter, and a thermometer installed on the outer peripheral surface of the bellows cover. [Figure 9] It is a diagram showing a specific example of deformation information and temperature information of the bellows expansion and contraction pipe. [Figure 10] It is a diagram showing a specific example of the calculation result of the thermal stress of the bellows expansion and contraction pipe. [Figure 11] It is a diagram showing a specific example of the calculation result of the degree of damage accumulated in the bellows expansion and contraction pipe.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. <Configuration of the bellows expansion and contraction pipe 100> FIG. 1 is a diagram showing an example of the external configuration of a bellows expansion and contraction pipe 100 which is a pipe joint to be monitored. FIGS. 2(A) and (B) are conceptual diagrams showing how the bellows expansion and contraction pipe 100 in FIG. 1 expands and contracts. FIGS. 3(A) to (C) are diagrams showing specific examples of a bellows cover 300 installed on the bellows expansion and contraction pipe 100, a measuring device 30, a displacement meter 40, and a thermometer 50 installed on the bellows cover 300.

[0010] The bellows expansion pipe 100 shown in Fig. 1 is a bridge erection bellows expansion pipe joint that connects a gas pipe 200, which is a pipe capable of supplying gas, in the pipe axis direction. The bellows expansion pipe 100 is capable of expanding and contracting in the pipe axis direction when the gas pipe 200 is connected. Specifically, as shown in Fig. 2(A), for example, when the gas pipe 200 expands in the pipe axis direction during a rise in temperature, the bellows expansion pipe 100 contracts in the pipe axis direction to absorb the amount by which the gas pipe 200 has expanded. Also, as shown in Fig. 2(B), for example, when the gas pipe 200 contracts in the pipe axis direction during a drop in temperature, the bellows expansion pipe 100 expands in the pipe axis direction to absorb the amount by which the gas pipe 200 has contracted. Thus, the bellows expansion pipe 100 absorbs the displacement in the pipe axis direction of the gas pipe 200 during a change in temperature, thereby relieving the thermal stress of the gas pipe 200.

[0011] As shown in Fig. 3(A), a pipe-shaped bellows cover 300 that changes its position in the pipe axis direction together with the bellows expansion pipe 100 is installed on the outer periphery of the bellows expansion pipe 100. That is, in Figs. 1 and 2 described above, only the bellows expansion pipe 100 connected to the gas pipe 200 is shown, but in reality, a bellows cover 300 that covers the bellows expansion pipe 100 is installed. For this reason, the bellows expansion pipe 100 is not exposed during normal times. Protrusions 310 are formed on the bellows cover 300, and as shown in Fig. 3(A), a measuring device 30 is installed on the protrusions 310. The protrusions 310 have functions such as preventing the outer peripheral surface of the bellows cover 300 from coming into contact with the bridge and wearing out.

[0012] Furthermore, as shown in Figure 3(B), a displacement gauge 40 capable of measuring the deformation of the bellows-type expansion joint 100 in the axial direction is installed on the bellows cover 300. A thermometer 50 capable of measuring the ambient temperature and the temperature of the bellows-type expansion joint 100 is also installed near the displacement gauge 40. An example of the thermometer 50 is shown in an enlarged view in Figure 3(C). The displacement gauge 40 and thermometer 50 are not particularly limited, and conventional types can be used. The displacement gauge 40 and thermometer 50 are installed at multiple locations on the outer surface of the bellows cover 300. Specific examples of the positions of multiple displacement gauges 40 and thermometers 50 installed at multiple locations on the outer surface of the bellows cover 300 will be described later with reference to Figure 8.

[0013] The measuring device 30 acquires the amount of deformation in the axial direction of the bellows-type expansion joint 100, measured by the displacement meter 40, and the temperature of the bellows-type expansion joint 100, measured by the thermometer 50, via wired or wireless connection. The measuring device 30 then transmits the acquired information to the management server 10 via the network 90 (see Figure 4), which will be described later, at a predetermined timing. The measuring device 30 is installed near the displacement meter 40 and the thermometer 50. For example, if the gas pipe 200 is installed along a bridge spanning a river, the bellows-type expansion joint 100 may be installed on both the bank side of the river and the other bank side. In this case, the combination of the measuring device 30, displacement meter 40, and thermometer 50 for monitoring the bellows-type expansion joint 100 will also be installed on both the bank side of the river and the other bank side.

[0014] <Configuration of Expansion Slot Monitoring System 1> Figure 4 shows an example of the overall configuration of the expansion joint monitoring system 1 to which this embodiment is applied. The expansion joint monitoring system 1 shown in Figure 4 is a system that enables monitoring of the fatigue life of the bellows-type expansion joint 100, regardless of the magnitude of expansion and contraction in the axial direction of the bellows-type expansion joint 100 shown in Figure 1. In this embodiment, "fatigue life" refers to the theoretical number of years until the bellows-type expansion joint 100 is subjected to stress and fails.

[0015] As shown in Figure 4, the expansion joint monitoring system 1 is configured by connecting a management server 10, measuring devices 30-1 to 30-n (where n is an integer value of 1 or more), and a user terminal 70 via a network 90. ​​The network 90 is, for example, a LAN (Local Area Network), the Internet, etc. Hereafter, unless it is necessary to explain each of the measuring devices 30-1 to 30-n individually, they will be collectively referred to as "measuring device 30".

[0016] The management server 10 is an information processing device that acts as a server for managing the entire expansion joint monitoring system 1, and functions as the expansion joint monitoring device of the present invention. The management server 10 is managed, for example, by a person who monitors the bellows-type expansion joint 100. The management server 10 transmits various types of information to the measuring device 30, the user terminal 70, and external sources, and enables the execution of various processes. The management server 10 also acquires various types of information transmitted from the measuring device 30, the user terminal 70, and external sources, and enables the execution of various processes.

[0017] For example, the management server 10 acquires information regarding the deformation of the bellows-type expansion joint 100 that connects the gas pipe 200 (hereinafter referred to as "deformation information"). The deformation information is the amount of deformation in the pipe axis direction of the bellows-type expansion joint 100 transmitted from the measuring device 30 installed on the bellows-type expansion joint 100, and specifically, it is the measured value from the displacement gauge 40 installed on the bellows cover 300. The management server 10 makes it possible to calculate the stress of the bellows-type expansion joint 100 from the acquired deformation information.

[0018] Furthermore, the management server 10 acquires information regarding the temperature of the bellows-type expansion joint 100 (hereinafter referred to as "temperature information") transmitted from the measuring device 30. Based on the deformation information regarding the displacement of the bellows-type expansion joint 100 due to the thermal expansion of the gas pipe 200 and the temperature information, the management server 10 is able to calculate the thermal stress as stress on the bellows-type expansion joint 100.

[0019] The management server 10 calculates the degree of accumulated damage to the bellows-type expansion joint 100 from the calculated stress history, and further calculates the fatigue life of the bellows-type expansion joint 100 from the calculated degree of damage. The management server 10 transmits information indicating the calculated fatigue life of the bellows-type expansion joint 100 to the user terminal 70. Details of the processing by the management server 10 will be described later.

[0020] The user terminal 70 is an information processing device, such as a smartphone, tablet, or personal computer, operated by a user who manages the bellows-type expansion joint 100 using the expansion joint monitoring system 1. The user terminal 70 is capable of transmitting various types of information to the management server 10 and external sources. The user terminal 70 is also capable of receiving various types of information transmitted from the management server 10 and external sources and performing various processes. For example, the user terminal 70 can receive information from the management server 10 indicating the fatigue life of the bellows-type expansion joint 100 and display it on a display or the like.

[0021] The configuration of the expansion joint monitoring system 1 described above is just one example; the expansion joint monitoring system 1 as a whole only needs to have the functionality to perform the processing described above. For this reason, some or all of the functions that perform the processing described above may be shared or performed collaboratively within the expansion joint monitoring system 1. In other words, some or all of the functions of the management server 10 that constitutes the expansion joint monitoring system 1 may be functions of other devices. Alternatively, some or all of the functions of other devices may be functions of the management server 10. Furthermore, some or all of the functions of the management server 10 or other devices that constitute the expansion joint monitoring system 1 may be transferred to other servers, etc. (not shown). This will facilitate the processing of the expansion joint monitoring system 1 as a whole, and also allow for the processing to be complemented by each other.

[0022] <Hardware Configuration> [Hardware configuration of management server 10] Figure 5 shows an example of the hardware configuration of the management server 10 that constitutes the expansion joint monitoring system 1 shown in Figure 4. The management server 10 includes a control unit 11, a memory 12, a storage unit 13, a communication unit 14, an operation unit 15, and a display unit 16. These units are connected by a data bus, an address bus, a PCI (Peripheral Component Interconnect) bus, etc.

[0023] The control unit 11 is a processor that controls the functions of the management server 10 through the execution of various software such as the OS (operating system) and application software. In this embodiment, various processes are executed on any computer. This computer may be implemented as a processor as hardware, a program as software, or a combination thereof. This computer may be a general-purpose computer, a computer for a specific purpose, a workstation, or any other system capable of executing various processes.

[0024] The processor is configured to perform various processes in cooperation with the program. The processor can function as each unit or each means in this embodiment. The execution order of the processes performed by the processor is not limited to the order described in this embodiment and can be changed as needed.

[0025] A processor can be composed of one or more hardware components. The types of hardware that make up a processor are not limited to any particular type. For example, a processor may be a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a programmable logic device such as an FPGA (Field Programmable Gate Array), a dedicated circuit for performing specific processing such as an ASIC (Application Specific Integrated Circuit), a GPU (Graphics Processing Unit), or a hardware component such as an NPU (Neural Processing Unit).

[0026] A processor can be configured not only with a combination of multiple hardware components of the same type, but also with a combination of multiple hardware components of different types. When multiple hardware components are configured to perform one or more processes of a given processor, these components may reside in physically separate devices or in the same device. Hardware is composed of electrical circuits, etc., which are combinations of circuit elements such as semiconductor devices.

[0027] In any embodiment, the execution order of various processes by the processor is not limited to the order described in each embodiment and can be changed as necessary. The program may be firmware or software such as microcode. The program may also be, for example, a group of program modules. Each function constituting the group of program modules may be implemented by a processor configured to execute each function. The program in each embodiment may be program code or multiple code segments stored in one or more non-temporary computer-readable media (e.g., semiconductor memory, magnetic or optical storage media, or other storage).

[0028] A program may be divided and stored on multiple non-temporary computer-readable media located on devices that are physically separated from each other. Program code and multiple code segments may be represented by any combination of procedures, functions, subprograms, routines, subroutines, modules, software packages, classes, instructions, data structures, and program statements. Program code and multiple code segments may be connected to other code segments or hardware circuits by sending and receiving information, data, arguments, parameters, or memory contents.

[0029] Memory 12 is a memory area that stores various software and data used for its execution, and is used as a work area during calculations. Memory 12 is composed of, for example, RAM (Random Access Memory).

[0030] The memory unit 13 is a memory area that stores input data for various software and output data from various software. The memory unit 13 is composed of, for example, an HDD (Hard Disk Drive), an SSD (Solid State Drive), or semiconductor memory used to store programs and various setting data. The memory unit 13 is provided with a database for storing various types of information. The database provided in the memory unit 13 stores various types of information, such as deformation information of the bellows-type expansion joint 100, temperature information, stress calculation results, damage degree calculation results, and fatigue life calculation results.

[0031] The communication unit 14 transmits and receives data between the measuring device 30, the user terminal 70, and the outside world via the network 90. ​​The operation unit 15 consists of, for example, a keyboard, mouse, mechanical buttons, and switches, and accepts input operations.

[0032] The operation unit 15 also includes a touch sensor that forms a touch panel integrally with the display unit 16. The display unit 16 is composed of, for example, a liquid crystal display or an organic EL (Electro-Luminescence) display used for displaying information, and displays image and text data. The display unit 16 displays a user interface, etc.

[0033] [Hardware configuration of user terminal 70] The user terminal 70 includes a control unit, memory, storage unit, communication unit, operation unit, and display unit, respectively, corresponding to the control unit 11, memory 12, storage unit 13, communication unit 14, operation unit 15, and display unit 16 shown in Figure 5 above.

[0034] <Functional Configuration> [Functional configuration of the control unit 11 of the management server 10] Figure 6 shows an example of the functional configuration of the control unit 11 of the management server 10 shown in Figure 5. The control unit 11 of the management server 10 functions as an information acquisition unit 111 for acquiring various types of information and an information management unit 112 for managing various types of information. The control unit 11 also functions as a stress calculation unit 113 for calculating the stress of the bellows-type expansion joint 100 and as a damage degree calculation unit 114 for calculating the degree of damage accumulated in the bellows-type expansion joint 100. The control unit 11 also functions as a lifespan calculation unit 115 for calculating the fatigue life of the bellows-type expansion joint 100 and as a transmission control unit 116 for controlling the transmission of various types of information.

[0035] The information acquisition unit 111 acquires various types of information transmitted from the measuring device 30, the user terminal 70, and external sources via the communication unit 14 (see Figure 5). For example, the information acquisition unit 111 acquires deformation information and temperature information transmitted from the measuring device 30.

[0036] The information management unit 112 stores and manages various types of information in the database of the storage unit 13 (see Figure 5). For example, the information management unit 112 stores and manages deformation information and temperature information of the bellows-type expansion joint 100 acquired by the information acquisition unit 111 in the database. The information management unit 112 also stores and manages the calculation results of the stress calculation unit 113, the damage degree calculation unit 114, and the lifespan calculation unit 115, which will be described later, in the database. Specific examples of deformation information and temperature information of the bellows-type expansion joint 100 will be described later with reference to Figure 9.

[0037] The stress calculation unit 113 enables the calculation of the stress of the bellows-type expansion joint 100 from the deformation information acquired by the information acquisition unit 111. Furthermore, the stress calculation unit 113 enables the calculation of thermal stress as stress of the bellows-type expansion joint 100 from the deformation information and temperature information acquired by the information acquisition unit 111.

[0038] For example, the stress calculation unit 113 makes it possible to calculate the stress of the bellows-type expansion joint 100 using the Kellogg formula (Annex JB.3.5 of JIS B 2352), which is an equation for calculating the total amount of expansion and contraction that the bellows-type expansion joint should absorb. When the gas pipe 200 (see Figure 1) deforms, the bellows-type expansion joint 100 may expand and contract in the direction of the pipe axis, or deform in a direction different from the direction of the pipe axis. The Kellogg formula makes it possible to replace these complex movements with expansion and contraction in the direction of the pipe axis and calculate them as the stress applied to the bellows-type expansion joint 100. A specific example of the calculation result of the thermal stress of the bellows-type expansion joint 100 will be described later with reference to Figure 10.

[0039] The damage calculation unit 114 calculates the degree of accumulated damage to the bellows-type expansion joint 100 from the stress history of the bellows-type expansion joint 100 calculated by the stress calculation unit 113. For example, the damage calculation unit 114 calculates the total value of the damage degree for each stress amplitude as the degree of damage. Here, "stress amplitude" is an index for evaluating the susceptibility of the bellows-type expansion joint 100 to fatigue failure, and indicates how much repeated stress the bellows-type expansion joint 100 is subjected to by the amplitude of the oscillation.

[0040] The damage calculation unit 114 may, for example, calculate the degree of damage accumulated in the bellows-type expansion joint 100 using the following formula 1. In formula 1, "D" represents the degree of damage accumulated in the bellows-type expansion joint 100. i " indicates the number of cycles actually applied to the bellows-type expansion joint 100 at stress level i, and "N i This indicates the allowable number of cycles that the bellows-type expansion joint 100 can withstand before fatigue failure occurs at stress level i. A specific example of the calculation result for the degree of accumulated damage to the bellows-type expansion joint 100 will be described later with reference to Figure 11.

[0041]

number

[0042] The lifespan calculation unit 115 calculates the fatigue life of the bellows-type expansion joint 100 from the degree of damage accumulated in the bellows-type expansion joint 100, which is calculated by the damage degree calculation unit 114. For example, when calculating the fatigue life in years, the fatigue life (years) can be expressed by the following formula 2. In formula 2, "LT" represents the fatigue life (years), and "D" represents the degree of damage accumulated in the bellows-type expansion joint 100, which is calculated by the damage degree calculation unit 114.

[0043]

number

[0044] The transmission control unit 116 controls the transmission of various types of information to the measuring device 30, the user terminal 70, and externally via the communication unit 14. For example, the transmission control unit 116 controls the transmission of the calculated fatigue life of the bellows-type expansion joint 100 as fatigue information to the user terminal 70.

[0045] <Processing flow of management server 10> Figure 7 is a flowchart showing an example of the processing flow of the management server 10. In Figure 7, "S" indicates a "step". When deformation information is transmitted from the measuring device 30 (YES in step 1), the management server 10 acquires the transmitted deformation information (step 2) and proceeds to the decision process in step 3. Conversely, if no deformation information is transmitted from the measuring device 30 (NO in step 1), the management server 10 repeats the decision process in step 1.

[0046] When the management server 10 receives temperature information from the measuring device 30 (YES in step 3), it acquires the transmitted temperature information (step 4) and proceeds to the process in step 5. Conversely, if no temperature information is transmitted from the measuring device 30 (NO in step 3), the management server 10 repeats the decision process in step 3.

[0047] The management server 10 calculates the stress of the bellows-type expansion joint 100 based on the deformation information obtained in step 2 and the temperature information obtained in step 4 (step 5), and proceeds to the processing in step 6. Specifically, in the processing of step 5, the management server 10 calculates the thermal stress as the stress of the bellows-type expansion joint 100 based on the deformation information and temperature information.

[0048] The management server 10 records the stress of the bellows-type expansion joint 100 calculated in step 5, calculates the degree of accumulated damage to the bellows-type expansion joint 100 from that history (step 6), and proceeds to the process in step 7.

[0049] The management server 10 calculates the fatigue life of the bellows-type expansion joint 100 based on the degree of damage accumulated to the bellows-type expansion joint 100 calculated in step 6 (step 7), and proceeds to the process in step 8.

[0050] The management server 10 sends the fatigue life of the bellows-type expansion joint 100, calculated in step 7, as fatigue information to the user terminal 70 (step 8), and terminates the process (END).

[0051] <Specific example> [Specific example of the arrangement of the measuring device 30, displacement meter 40, and thermometer 50] Figure 8 is a conceptual diagram showing a specific example of the positional relationship between the measuring device 30, the displacement meter 40, and the thermometer 50, which are installed on the outer surface of the bellows cover 300. Figure 8 shows a cross-sectional view of a bellows-type expansion joint 100 and bellows cover 300, which are installed along the bridge 500 together with the gas pipe 200 (see Figure 1), cut in a direction perpendicular to the pipe axis.

[0052] As shown in Figure 8, the outer surface of the bellows cover 300 has multiple protrusions 310 formed at various locations. Furthermore, a measuring device 30, displacement gauges 40-1 to 40-3, and a thermometer 50 are arranged on the outer surface of the bellows cover 300. The displacement gauges 40-1 to 40-3 are spaced apart as shown in Figure 8, thereby improving the reliability of the measurement results and the accuracy of the calculation results.

[0053] Each of the displacement gauges 40-1 to 40-3 measures the amount of deformation of the bellows-type expansion joint 100 in the axial direction at its respective position. The thermometer 50 is capable of measuring the ambient temperature and the temperature of the bellows-type expansion joint 100. The measuring device 30 acquires the measurement results from the displacement gauges 40-1 to 40-3 and the measurement results from the thermometer 50 via wired or wireless connection. The measuring device 30 then transmits the acquired measurement results to the management server 10 via the network 90 (see Figure 4) at a predetermined timing.

[0054] [Specific examples of deformation information and temperature information] Figure 9 shows specific examples of deformation information and temperature information for the bellows-type expansion joint 100. Figure 9 shows a graph illustrating specific examples of deformation and temperature information for a bellows-type expansion joint 100 (see Figure 1) installed as a joint for a gas pipe 200 (see Figure 1) that is installed along a bridge spanning a river.

[0055] The graph shown in Figure 9 has time on the horizontal axis and "displacement (mm)" and "temperature (°C)" on the vertical axis. The measured values ​​of "displacement (mm)" as deformation information are shown as dotted lines, and the measured values ​​of "temperature (°C)" as temperature information are shown as solid lines. As shown in the graph in Figure 9, measurements were taken over approximately 5 months (September 4, 2024 to January 31, 2025) with the deformation information acquired on September 4, 2024 set to 0 (zero).

[0056] As shown in Figure 9, the bellows-type expansion joint 100 is displaced in response to changes in temperature. Specifically, a maximum displacement of approximately 80 mm is observed during the measurement period shown in the figure.

[0057] [Specific examples of thermal stress calculation results] Figure 10 shows a specific example of the calculation results for the thermal stress of a bellows-type expansion joint 100. Figure 10 shows a specific example of thermal stress calculated from deformation and temperature information obtained on the first side, illustrated in a graph. The graph in Figure 10 has time on the horizontal axis and "bellows thermal stress σa (Mpa)" on the vertical axis.

[0058] The graph in Figure 10 shows the thermal stress amplitude S of the bellows. a This is shown. Bellows thermal stress amplitude S a This is the range of stress fluctuation caused by the expansion and contraction of the bellows-type expansion joint 100 in the axial direction due to changes in temperature. (Bellows thermal stress amplitude S) a This is calculated using the Kellogg formula described above from the measured value of the displacement (mm) in the axial direction of the bellows-type expansion joint 100. The bellows-type expansion joint 100 undergoes fatigue because it repeatedly expands and contracts in response to the temperature rise and fall of the gas pipe 200 (see Figure 1). Therefore, the thermal stress amplitude S of the bellows a This serves as an important indicator for calculating the degree of cumulative damage to the bellows-type expansion joint 100.

[0059] [Specific examples of calculation results for the cumulative degree of damage] Figure 11 shows a specific example of the calculation result of the degree of damage accumulated in the bellows-type expansion joint 100. The degree of damage accumulated in the bellows expansion joint 100 is calculated from the stress history of the bellows expansion joint 100. For example, the degree of damage accumulated in the bellows expansion joint 100 is calculated by the above-mentioned formula (1). In FIG. 11, a specific example of the degree of damage accumulated in the bellows expansion joint 100 is shown graphically. The graph shown in FIG. 11 has the horizontal axis as " f (number of cycles) N a " and the vertical axis as "bellows thermal stress amplitude S

[0060] (Mpa)". f "

[0061] <Other embodiments> As described above, the present embodiment has been described, but the present invention is not limited to the above-described present embodiment. Also, the effects of the present invention are not limited to those described in the above-described present embodiment. For example, the external appearance configuration and functions of the bellows expansion joint 100 shown in FIGS. 1 and 2, and the configurations of the bellows cover 300, the measuring device 30, the displacement meter 40, and the thermometer 50 shown in FIG. 3 are merely examples for achieving the object of the present invention and are not particularly limited. Also, the overall configuration of the expansion joint monitoring system 1 shown in FIG. 4, the hardware configuration of the management server 10 shown in FIG. 5, and the functional configuration of the management server 10 in FIG. 6 are merely examples for achieving the object of the present invention and are not particularly limited. That is, it is sufficient that the expansion joint monitoring system 1 in FIG. 4 has a function capable of executing the above-described processing as a whole, and the hardware configuration and functional configuration used to realize this function are not limited to the above examples.

[0062] Furthermore, the order of the processing steps of the management server 10 shown in the flowchart of Figure 7 is merely illustrative and not particularly limiting. Processing is not limited to being performed chronologically according to the illustrated step order; it may also be performed in parallel or individually, not necessarily chronologically. For example, in Figure 7, deformation information is acquired before temperature information, but this order is arbitrary, and the deformation information and temperature information may be transmitted and acquired as a set. Also, the arrangement of the measuring device 30, displacement meter 40, and thermometer 50 shown in Figure 8 is merely an example and not particularly limiting. In addition, specific examples of deformation information and temperature information shown in Figure 9, the calculation results of thermal stress shown in Figure 10, and the calculation results of the cumulative degree of damage shown in Figure 11 are also examples and not particularly limiting.

[0063] Furthermore, the above-mentioned formulas 1 and 2 are merely examples of methods used to calculate the degree of accumulated damage to the bellows-type expansion joint 100 and the fatigue life of the bellows-type expansion joint 100, respectively, and are not particularly limited.

[0064] Furthermore, while the above-described embodiment assumes that the pipe to which the bellows-type expansion joint 100, as an expandable pipe joint, is connected is a gas pipe 200, it is not limited to this. Any pipe that can be connected to the expandable pipe joint is acceptable, so for example, it may be piping for water, steam, oil, chemicals, etc.

[0065] In summary, the expansion joint monitoring system 1 of the present invention only needs to have the following configuration and can take on various forms. In other words, the expansion joint monitoring system 1 is an expansion joint monitoring system having an acquisition means (for example, an information acquisition unit 111 in Figure 6) for acquiring deformation information relating to the deformation of an expandable pipe joint (for example, a bellows-type expansion joint 100 in Figure 1) that connects a pipe (for example, a gas pipe 200 in Figure 1), a stress calculation means (for example, a stress calculation unit 113 in Figure 6) for calculating the stress of the pipe joint from the acquired deformation information, a damage degree calculation means (for example, a damage degree calculation unit 114 in Figure 6) for calculating the degree of accumulated damage to the pipe joint from the calculated stress history of the pipe joint, and a lifespan calculation means (for example, a lifespan calculation unit 115 in Figure 6) for calculating the fatigue life of the pipe joint from the calculated degree of damage. This allows monitoring of the fatigue life of pipe joints regardless of the magnitude of expansion or contraction of the expandable pipe joint.

[0066] Here, the acquisition means may be to acquire the amount of deformation of the pipe joint in the pipe axis direction as deformation information, measured by a displacement meter installed on the pipe joint (for example, the displacement meter 40 shown in Figure 3(B)). This makes it possible to monitor the fatigue life of pipe joints based on the amount of deformation in the pipe axis direction.

[0067] Furthermore, displacement sensors may be installed at multiple locations in the circumferential direction of the pipe joint. This allows for handling cases where the pipe joint is bent.

[0068] Alternatively, the acquisition means may acquire temperature information regarding the temperature of the pipe joint measured by a thermometer (for example, the thermometer 50 shown in Figure 3(C)) installed near the displacement meter, and the stress calculation means may calculate the thermal stress as the stress of the pipe joint based on the deformation information regarding the displacement of the pipe joint due to the thermal expansion of the pipe and the temperature information. This makes it possible to monitor the fatigue life of pipe joints based on the amount of deformation in the pipe axis direction of the pipe joint due to the thermal expansion of the pipe.

[0069] Furthermore, the pipe joint may be a bridge-mounted bellows-type expansion joint that connects pipes capable of supplying gas. This makes it possible to monitor the fatigue life of bridge-mounted bellows-type expansion joints based on the amount of deformation in the pipe axis direction of the bridge-mounted bellows-type expansion joint due to the thermal expansion of gas pipes.

[0070] Furthermore, the management server 10, which is an example of the expansion joint monitoring device of the present invention, only needs to have the following configuration and can take on various forms. In other words, the management server 10 is an expansion joint monitoring device having an acquisition means for acquiring deformation information relating to the deformation of an expandable pipe joint connecting pipes, a stress calculation means for calculating the stress of the pipe joint from the acquired deformation information, a damage degree calculation means for calculating the degree of damage accumulated in the pipe joint from the calculated stress history, and a lifespan calculation means for calculating the fatigue life of the pipe joint from the calculated degree of damage. This allows monitoring of the fatigue life of pipe joints regardless of the magnitude of expansion or contraction of the expandable pipe joint.

[0071] Furthermore, the expansion joint monitoring method of the present invention only requires the following configuration, and various embodiments can be adopted. In other words, the expansion joint monitoring method of the present invention is an expansion joint monitoring method that includes the steps of: acquiring deformation information relating to the deformation of an expandable pipe joint connecting pipes; calculating the stress of the pipe joint from the acquired deformation information; calculating the degree of accumulated damage to the pipe joint from the calculated stress history; and calculating the fatigue life of the pipe joint from the calculated degree of damage. This allows monitoring of the fatigue life of pipe joints regardless of the magnitude of expansion or contraction of the expandable pipe joint.

[0072] Furthermore, the program of the present invention only needs to have the following configuration and can take on various embodiments. In other words, the program of the present invention is a program for a computer to implement control processing that includes a function to acquire deformation information relating to the deformation of an expandable pipe joint connecting pipes, a function to calculate the stress of the pipe joint from the acquired deformation information, a function to calculate the degree of accumulated damage to the pipe joint from the calculated stress history, and a function to calculate the fatigue life of the pipe joint from the calculated degree of damage. This allows monitoring of the fatigue life of pipe joints regardless of the magnitude of expansion or contraction of the expandable pipe joint. [Explanation of Symbols]

[0073] 1... Expansion joint monitoring system, 10... Management server, 11... Control unit, 12... Memory, 13... Storage unit, 14... Communication unit, 15... Operation unit, 16... Display unit, 30... Measuring device, 40... Displacement meter, 50... Thermometer, 70... User terminal, 90... Network, 100... Bellows-type expansion joint, 111... Information acquisition unit, 112... Information management unit, 113... Stress calculation unit, 114... Damage degree calculation unit, 115... Lifespan calculation unit, 116... Transmission control unit, 200... Gas pipe, 300... Bellows cover, 310... Protrusion, 500... Bridge

Claims

1. A means for acquiring deformation information regarding the deformation of expandable pipe joints that connect pipes, A stress calculation means for calculating the stress of the pipe joint from the acquired deformation information, Damage degree calculation means for calculating the degree of accumulated damage to the pipe joint from the calculated stress history, A life calculation means for calculating the fatigue life of the pipe joint from the calculated degree of damage, It has, The acquisition means acquires the amount of deformation of the pipe joint in the pipe axis direction, measured by a displacement meter installed on the pipe joint, as the deformation information. The acquisition means further acquires temperature information relating to the temperature of the pipe joint, which is measured by a thermometer installed near the displacement meter. The stress calculation means calculates the thermal stress as the stress of the pipe joint based on the deformation information relating to the displacement of the pipe joint due to the thermal expansion of the pipe and the temperature information. Expansion joint monitoring system.

2. The aforementioned pipe joint is a bridge-mounted bellows-type expansion joint that connects the aforementioned pipes capable of supplying gas. The expansion joint monitoring system according to claim 1.

3. A means for acquiring deformation information regarding the deformation of expandable pipe joints that connect pipes, A stress calculation means for calculating the stress of the pipe joint from the acquired deformation information, Damage degree calculation means for calculating the degree of accumulated damage to the pipe joint from the calculated stress history, A life calculation means for calculating the fatigue life of the pipe joint from the calculated degree of damage, It has, The acquisition means acquires the amount of deformation of the pipe joint in the pipe axis direction, measured by a displacement meter installed on the pipe joint, as the deformation information. The acquisition means further acquires temperature information relating to the temperature of the pipe joint, which is measured by a thermometer installed near the displacement meter. The stress calculation means calculates the thermal stress as the stress of the pipe joint based on the deformation information relating to the displacement of the pipe joint due to the thermal expansion of the pipe and the temperature information. Expansion joint monitoring device.

4. A step of obtaining deformation information regarding the deformation of an expandable pipe joint that connects pipes, A step of calculating the stress of the pipe joint from the acquired deformation information, A step of calculating the degree of damage accumulated in the pipe joint from the calculated stress history, A step of calculating the fatigue life of the pipe joint from the calculated degree of damage, Includes, In the step of acquiring the deformation information, the amount of deformation of the pipe joint in the pipe axis direction, measured by a displacement meter installed on the pipe joint, is acquired as the deformation information. Further temperature information regarding the temperature of the pipe joint, measured by a thermometer installed near the displacement meter, is acquired. In the step of calculating the stress of the pipe joint, the thermal stress is calculated as the stress of the pipe joint based on the deformation information relating to the displacement of the pipe joint due to the thermal expansion of the pipe and the temperature information. Expansion joint monitoring method.

5. On the computer, A function to acquire deformation information regarding the deformation of expandable pipe joints that connect pipes, A function to calculate the stress of the pipe joint from the acquired deformation information, A function to calculate the degree of damage accumulated in the pipe joint from the calculated stress history, A function to calculate the fatigue life of the pipe joint from the calculated degree of damage, A function to acquire the amount of deformation of the pipe joint in the pipe axis direction, measured by a displacement meter installed on the pipe joint, as deformation information, A function to acquire temperature information regarding the temperature of the pipe joint, measured by a thermometer installed near the displacement sensor, A function to calculate thermal stress as the stress on the pipe joint based on deformation information relating to the displacement of the pipe joint due to the thermal expansion of the pipe and temperature information, A program for implementing control processing that includes this.

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