Jacking pipe joint stress monitoring method based on mechanoluminescent material

Abstract

The invention discloses a jacking pipe joint stress monitoring method based on a mechanoluminescent material. The jacking pipe joint stress monitoring method comprises the following steps: step A, obtaining a stress-wavelength curve graph of the mechanoluminescent material; step B, spraying a mechanoluminescent material on the inner wall of the pipe joint along the circumferential direction; and C, in the pipe jacking construction process, the wavelength of light emitted by the mechanoluminescent material on the inner wall of the pipe joint is collected and analyzed, and the stress size corresponding to the wavelength of the light is determined in combination with the stress-wavelength curve graph obtained in the step A. In the jacking process of the pipe joint, the mechanoluminescent material can emit light due to stress, the wavelength of light emitted by the mechanoluminescent material on the inner wall of the pipe joint is collected and analyzed by means of an optical analysis system, data are transmitted to a computer, and the stress corresponding to the wavelength of light can be determined by combining a stress-wavelength curve graph obtained previously. According to the method, the stress state of each position of the pipe joint is judged, the stress of the pipe joint in the jacking process is monitored, the error is small, and the pipe clamping position can be rapidly determined.

Description

Technical Field

[0001] The invention relates to the technical field of pipe jacking construction monitoring, and in particular to a method for monitoring the stress of a pipe jacking section based on a mechanoluminescent material. Background Art

[0002] With the acceleration of urbanization, the demand for underground infrastructure construction is increasing. As a trenchless construction method, pipe jacking technology has the advantages of short construction period, small disturbance to the ground environment and high construction safety. It is widely used in urban pipeline laying, traffic tunnel construction and other underground engineering projects.

[0003] With the continuous innovation and development of pipe jacking technology, the conditions for pipe jacking construction are becoming increasingly complex, and more and more construction problems are faced. Especially in long-distance pipe jacking construction, it is easy to get stuck, resulting in abnormal jacking force. In severe cases, excessive jacking force may cause pipe joints to rupture, resulting in engineering accidents. When the pipe is stuck, you should first try to increase the jacking force instantly. If it is increased to the maximum value that the pipe joint can withstand under normal use conditions and still cannot be pushed smoothly, it is necessary to monitor the pipe jacking construction during jacking to determine the location of the stuck pipe and adopt other measures to deal with the pipe jacking problem.

[0004] At present, the method to determine the location of the stuck pipe is mainly to obtain data by pre-burying sensors inside or at local locations on the surface of several pipe sections, and inferring the stress state of the entire pipe section based on these sensor data, and then determining the location of the stuck pipe. However, burying and arranging sensors is not only complicated, but also has a low survival rate. In addition, the data obtained by the sensors can only determine the stress state of the local position of the pipe section. The stress state of other positions of the pipe section or even the entire pipe section needs to be determined by speculation, lacking specific stress values, and resulting in large errors. Summary of the invention

[0005] The purpose of the present invention is to provide a method for monitoring the stress of pipe joints in pipe jacking based on mechanoluminescent materials in order to solve the problem that the existing methods for judging the stress state of pipe joints in pipe jacking construction have large errors. The method can monitor the stress state of pipe joints during normal jacking to ensure that each pipe joint is in a safe state. The method not only has a small error, but also can quickly determine the position of the stuck pipe after it occurs so as to take corresponding measures.

[0006] The present invention is achieved through the following technical solutions:

[0007] The present invention provides a method for monitoring the stress of a pipe joint based on a mechanoluminescent material, comprising the following steps:

[0008] Step A, obtaining a stress-wavelength curve of a mesoluminescent material;

[0009] Step B, spraying the mesoluminescent material onto the inner wall of the pipe section along the circumferential direction;

[0010] Step C: During the pipe jacking construction process, the wavelength of light emitted by the mechanoluminescent material on the inner wall of the pipe segment is collected and analyzed, and then combined with the stress-wavelength curve obtained in step A to determine the stress size corresponding to the wavelength of light.

[0011] As a preferred embodiment of the present invention, obtaining the stress-wavelength curve of the mechanoluminescent material in step A specifically includes the following steps:

[0012] Step A1, prepare a test block with the same material as the pipe segment, and spray the mechanoluminescent material on its surface;

[0013] Step A2, applying a linearly varying pressure to the test block, collecting and analyzing the wavelength of light emitted by the mechanoluminescent material in real time, and obtaining a compressive stress-light wavelength curve of the mechanoluminescent material;

[0014] Step A3, applying a linearly varying tensile force to the test block, collecting and analyzing the wavelength of light emitted by the mechanoluminescent material in real time, and obtaining a tensile stress-light wavelength curve of the mechanoluminescent material;

[0015] Step A4: combine the compressive stress-light wavelength curve obtained in step A2 with the tensile stress-light wavelength curve obtained in step A3 to obtain a stress-wavelength curve of the mesoluminescent material.

[0016] As a preferred embodiment of the present invention, in step A, the wavelength and stress value corresponding to the cracks in the test block are marked, and are appropriately reduced as warning values ​​for cracks in the pipe joint during actual pipe jacking construction.

[0017] As a preferred embodiment of the present invention, in step B, the mesoluminescent material is sprayed at three locations on the inner wall of the pipe segment, and the three spraying locations are respectively located at the inner wall of the pipe segment near the two end joints and the middle part of the pipe segment.

[0018] As a preferred embodiment of the present invention, after the force-induced luminescent material sprayed on the inner wall of the pipe segment in step B is cured, a layer of transparent resin material is sprayed on the force-induced luminescent material, and after curing, a transparent protective layer is formed outside the force-induced luminescent material.

[0019] As a preferred embodiment of the present invention, in step C, the wavelength of light emitted by the mechanoluminescent material on the inner wall of the pipe segment is collected and analyzed in real time along the circumferential direction at a certain rotational angular velocity to generate a wavelength-circumferential angle curve graph, and then the pipe segment stress-circumferential angle curve graph is obtained in combination with the stress-wavelength curve graph, thereby realizing real-time monitoring of the pipe segment stress.

[0020] As a preferred embodiment of the present invention, in step C, an optical probe is installed on the inner wall of the pipe segment, and the optical probe is used to collect light emitted by the mesoluminescent material and transmit it to an optical analysis system to analyze the wavelength of the light.

[0021] As a preferred embodiment of the present invention, in step C, a fixture is installed on the inner wall of the pipe segment, the fixture has a turntable, the rotation axis of the turntable is along the axial direction of the pipe segment, and the optical probe is installed on the turntable.

[0022] As a preferred solution of the present invention, the optical probe and the mechanoluminescent material to be collected are located in the same section of the tube segment.

[0023] As a preferred solution of the present invention, the fixture is connected to a computer via an angular velocity controller, and the angular velocity of the optical probe driven by the turntable on the fixture is controlled by the computer.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] 1. In the present invention, the stress of the pipe joint is monitored by spraying the mechanoluminescent material inside the pipe joint. The spraying operation is safe and simple, which saves the tedious process of installing the sensor and does not need to consider the survival rate like the sensor;

[0026] 2. The present invention can monitor the stress state of the pipe section during the normal jacking process of the jacking pipe, so as to timely adjust the grouting of the jacking pipe construction, ensure that each pipe section is in a safe state, and ensure the smooth completion of the construction. In addition, the present invention sprays the force-induced luminescent material on the entire cross-section of the inner wall of the pipe section, which can monitor the stress of the entire cross-section of the pipe section. Not only is the error small, but the friction resistance of the pipe section can also be obtained according to the stress difference before and after the pipe section. If necessary, the force-induced luminescent material can even be sprayed on the inner wall of the entire pipe section to monitor the entire pipe section.

[0027] 3. Especially for the problem of pipe jamming which is very easy to occur during long-distance pipe jacking construction, the present invention can not only quickly determine the position of the stuck pipe after it occurs so as to take corresponding measures to avoid excessive delays in the construction period, but also ensure that the stress on the pipe section is lower than the warning value during the process of increasing the jacking force, thereby ensuring construction safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0029] Figure 1 It is a flow chart of the method for monitoring the stress of the pipe joint based on the mechanoluminescent material in the present invention;

[0030] Figure 2 A schematic diagram of the installation and connection of related equipment for obtaining a curve of the relationship between the wavelength of light emitted by a mechanoluminescent material and the pressure exerted on a concrete test block in the present invention;

[0031] Figure 3 A schematic diagram of spraying a mechanoluminescent material on one side of a concrete test block in the present invention;

[0032] Figure 4 It is a schematic diagram of spraying the mechanoluminescent material and the resin material on the inner wall of the top pipe section in the present invention;

[0033] Figure 5 This is a schematic diagram of the installation and connection of related equipment for monitoring pipe segment stress during pipe jacking construction in the present invention.

[0034] Marks and corresponding parts names in the attached drawings:

[0035] 1- uniaxial compression testing machine, 2- mechanical sensor, 3- optical analysis system, 4- computer, 5- test block, 6- mechanoluminescent material, 7- optical probe, 8- pipe section, 9- resin material, 10- fixture, 11- angular velocity controller. DETAILED DESCRIPTION

[0036] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0038] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0039] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0040] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists, A and B exist at the same time, and B exists. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0041] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0042] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces), unless otherwise clearly and specifically defined.

[0043] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0044] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0045] At present, the method of determining the location of a stuck pipe in pipe jacking construction is mainly to obtain data by pre-burying sensors inside or at local locations on the surface of several pipe sections, and inferring the stress state of the entire pipe section based on these sensor data, and then determining the location of the stuck pipe. However, burying and arranging sensors is not only a complicated process, but also has a low survival rate. In addition, the data obtained by the sensors can only determine the stress state of the local position of the pipe section. The stress state of other positions of the pipe section or even the entire pipe section needs to be determined by speculation, lacking specific stress values, and resulting in large errors.

[0046] To this end, the inventors have conducted in-depth research and invented a method for monitoring the stress of pipe joints based on mechanoluminescent materials. This method involves spraying the mechanoluminescent material on the inner wall section of the pipe joint. During the pipe jacking process, the wavelength of light emitted by the mechanoluminescent material on the inner wall of the pipe joint is collected and analyzed. Combined with the pre-obtained stress-wavelength curve, the stress corresponding to the wavelength of light can be determined, thereby judging the stress state of each position of the pipe joint and realizing the monitoring of the pipe joint stress during the jacking process.

[0047] Please refer to Figures 1 to 5 A method for monitoring the stress of a pipe joint based on a mechanoluminescent material provided in an embodiment of the present application comprises the following steps:

[0048] Step A, obtaining a stress-wavelength curve diagram of the mesoluminescent material 6;

[0049] Step B, spraying the mesoluminescent material 6 onto the inner wall of the pipe section 8 along the circumferential direction;

[0050] Step C: During the pipe jacking construction process, the wavelength of light emitted by the mesoluminescent material 6 on the inner wall of the pipe segment 8 is collected and analyzed, and then combined with the stress-wavelength curve obtained in step A to determine the stress size corresponding to the wavelength of light.

[0051] The present application sprays the mechanoluminescent material 6 onto the inner wall section of the pipe segment 8. During the process of pipe jacking, the wavelength of light emitted by the mechanoluminescent material 6 on the inner wall of the pipe segment 8 is collected and analyzed. Combined with the stress-wavelength curve of the mechanoluminescent material 6 obtained in advance, the stress corresponding to the wavelength of light can be determined, thereby judging the stress state of each position of the pipe segment 8 and realizing the monitoring of the stress state of the pipe segment 8 during the jacking process. This method can ensure that each pipe segment 8 is in a safe state, not only with a small error, but also with the ability to quickly determine the position of the stuck pipe after it occurs, so as to take corresponding measures.

[0052] According to some embodiments of the present application, the stress-wavelength curve of the mechanoluminescent material 6 is obtained in step A, taking the concrete pipe jacking project as an example, and specifically includes the following steps:

[0053] Step A1: prepare a concrete test block 5 with the same material ratio as the jacking pipe segment 8, and spray the surface of the concrete test block 5 with a mesoluminescent material 6. The mesoluminescent material 6 will emit light of different wavelengths under different pressures.

[0054] Step A2, placing the concrete test block 5 on the uniaxial compression testing machine 1, the uniaxial compression testing machine 1 is connected to a mechanical sensor 2, which is used to collect and record in real time the magnitude of the force applied by the uniaxial compression testing machine 1 during the pressurization of the concrete test block 5, and transmit the collected and recorded data to the computer 4.

[0055] When the uniaxial compression testing machine 1 applies pressure to the concrete test block 5, the mechanoluminescent material 6 sprayed on the surface of the concrete test block 5 will emit light, and the optical probe 7 of the optical analysis system 3 will detect and receive the light emitted by the mechanoluminescent material 6 in real time, and then collect and transmit it through the optical fiber. The wavelength of the light is measured by the optical analysis system 3, so as to obtain the wavelength of the light emitted by the mechanoluminescent material 6 under different pressures, and finally transmit the data to the computer 4.

[0056] Step A3, after the test starts, the pressure applied by the uniaxial compression testing machine 1 increases linearly with time, which will cause the wavelength of the light emitted by the mechanoluminescent material 6 to gradually change. The mechanical sensor 2 collects and records the magnitude of the applied force in real time. At the same time, the optical probe 7 detects and collects the light emitted by the mechanoluminescent material 6 in real time and transmits it to the optical analysis system 3 through the optical fiber to analyze the wavelength of the light. Finally, the data of the mechanical sensor 2 and the optical analysis system 3 are transmitted to the computer 4, and the relationship curve between the wavelength of the light emitted by the mechanoluminescent material 6 under pressure and the pressure on the concrete test block is obtained on the computer, that is, the compressive stress-light wavelength curve of the mechanoluminescent material 6 is obtained.

[0057] Step A4, replace the uniaxial compression testing machine 1 with a tensile testing machine, repeat the above process, draw a curve of the relationship between the wavelength of the light emitted by the mesoluminescent material 6 under tension and the tensile force exerted on the concrete test block 5, that is, obtain the tensile stress-light wavelength curve of the mesoluminescent material 6, and combine it with the compressive stress-light wavelength curve obtained in step A3 to obtain the (tensile and compressive) stress-wavelength curve of the mesoluminescent material 6.

[0058] According to some embodiments of the present application, in step A, the wavelength and stress value corresponding to the occurrence of cracks in the concrete test block 5 are marked, and are appropriately reduced as warning values ​​for the occurrence of cracks in the concrete pipe section during actual pipe jacking construction.

[0059] According to some embodiments of the present application, in step B, three locations of the electroluminescent material 6 are sprayed on the inner wall of the pipe segment, and the three spraying locations are respectively located on the inner wall of the pipe segment near the two end joints and in the middle of the pipe segment.

[0060] During the actual pipe jacking construction, since the joints at both ends of the concrete pipe segment 8 are very likely to crack due to stress concentration, the force-induced luminescent material 6 is sprayed on the inner wall of the concrete pipe segment 8 near the joints at both ends, and then the force-induced luminescent material 6 is sprayed on the middle part of the pipe segment 8 to form a contrast with the joints at both ends, so as to better analyze the stress condition of the pipe segment.

[0061] According to some embodiments of the present application, after the force-induced luminescent material 6 sprayed on the inner wall of the pipe segment 8 in step B is cured, a layer of transparent resin material 9 is sprayed on the force-induced luminescent material 6, and a transparent protective layer is formed outside the force-induced luminescent material 6 after the resin material 9 is cured.

[0062] In order to ensure that the mechanoluminescent material 6 sprayed on the inner wall of the pipe section 8 is not damaged during the jacking process, a layer of flexible and transparent resin material 9 is sprayed on the upper layer of the mechanoluminescent material after the mechanoluminescent material 6 is sprayed. The resin material 9 has a certain strength and high light transmittance after curing, which can not only ensure that the mechanoluminescent material 6 is not damaged during the construction process, but also does not affect the collection of the wavelength of light emitted by the mechanoluminescent material 6 (Note: Figure 4 In order to more clearly express the situation of spraying two materials on the inner wall of the pipe segment, only the partial figure of the spraying resin material 9 is shown).

[0063] According to some embodiments of the present application, in step C, the wavelength of light emitted by the mesoluminescent material 6 on the inner wall of the pipe segment 8 is collected and analyzed in real time along the circumferential direction at a certain rotational angular velocity to generate a wavelength-circumferential angle curve graph, and then the pipe segment stress-circumferential angle curve graph is obtained in combination with the stress-wavelength curve graph, thereby achieving real-time monitoring of the pipe segment stress.

[0064] Specifically, during construction, a fixture 10 is fixed near the section where the electroluminescent material 6 is sprayed on the inner wall of the pipe segment, and the fixture 10 is mainly used to install the optical probe 7. The fixture 10 has a turntable, the rotation axis of the turntable is along the axial direction of the pipe segment, and the optical probe 7 is installed on the turntable.

[0065] The fixture 10 is equipped with a battery for power supply, one end of which is fixed to the inner wall of the pipe section, and the turntable at the other end can rotate at a constant angular velocity. The turntable of the fixture 10 is fixed to the optical probe 7 by threads and can drive the optical probe 7 to rotate. During installation, it is necessary to ensure that the optical probe 7 and the sprayed mechanoluminescent material 6 are located in the same section of the pipe section.

[0066] The fixture 10 is connected to the computer 4 via the angular velocity controller 11, and the angular velocity of the optical probe 7 driven by the fixture 10 can be controlled by the computer 4, and the rotation angle of the fixture 10 at a certain moment can be recorded in real time on the computer, with 360° as a cycle. The optical probe 7 is connected to the optical analysis system 3, and the optical analysis system is connected to the computer 4.

[0067] During normal jacking, the angular velocity of the rotating table of the fixture 10 is first set by the computer 4. The light emitted by the mechanoluminescent material 6 will emit different wavelengths due to the change in the stress on the pipe joint. The optical probe 7 rotates at the set angular velocity and collects the wavelength of the light emitted by the mechanoluminescent material 6 of a certain section. After the optical analysis system 3 collects and analyzes the wavelength of the light, the data is transmitted to the computer 4. The wavelength-clamp rotation angle curve is first generated on the computer, and then the pipe joint stress-clamp rotation angle curve can be obtained with the help of the previously obtained (tension and compression) stress-wavelength curve and the computer. In this way, the purpose of real-time monitoring of the stress of the jacking pipe joint during the construction process can be achieved to ensure that the stress on the pipe joint is lower than the warning value, and the friction resistance on the pipe joint can also be obtained according to the stress difference before and after the pipe joint.

[0068] When a pipe gets stuck during pipe jacking construction, the jacking force is gradually increased when determining the stuck pipe position. The wavelength of the force-induced luminescent material 6 sprayed on the inner wall of the pipe segment between the oil cylinder and the stuck pipe position gradually approaches the warning value, while the wavelength of the force-induced luminescent material 6 sprayed on the inner wall of the pipe segment in front of the stuck pipe position remains almost unchanged, and the data features are obviously differentiated. Based on this, the pipe segment where the wavelength emitted by the force-induced luminescent material 6 gradually approaches the warning value can be judged as the stuck pipe position, and the next treatment measure can be taken.

[0069] In the process of pipe joint jacking, the force-induced luminescent material will emit light due to the force. With the help of an optical analysis system, the wavelength of light emitted by the force-induced luminescent material on the inner wall of the pipe joint is collected and analyzed, and the data is transmitted to a computer. Combined with the previously obtained stress-wavelength curve, the stress size corresponding to the wavelength of light can be determined, thereby judging the stress state of each position of the pipe joint and realizing the monitoring of the pipe joint stress during the jacking process. In particular, after the pipe jamming phenomenon occurs, the jacking force is increased, and the wavelength emitted by the force-induced luminescent material sprayed on the inner wall of the pipe joint between the oil cylinder and the pipe jamming position gradually approaches the warning value, while the wavelength of the force-induced luminescent material sprayed on the inner wall of the pipe joint in front of the pipe jamming position remains almost unchanged, based on which the position of the pipe jamming can be judged.

[0070] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for monitoring the stress of a pipe joint based on a mechanoluminescent material, characterized in that: The following steps are involved: Step A, obtaining a stress-wavelength curve of a mesoluminescent material; Step B, spraying the mesoluminescent material onto the inner wall of the pipe section along the circumferential direction; Step C: During the pipe jacking construction process, the wavelength of light emitted by the mechanoluminescent material on the inner wall of the pipe segment is collected and analyzed, and then combined with the stress-wavelength curve obtained in step A to determine the stress size corresponding to the wavelength of light.

2. The method for monitoring the stress of a pipe joint based on a mechanoluminescent material according to claim 1, characterized in that: The step A of obtaining the stress-wavelength curve of the mechanoluminescent material specifically includes the following steps: Step A1, prepare a test block with the same material as the pipe segment, and spray the mechanoluminescent material on its surface; Step A2, applying a linearly varying pressure to the test block, collecting and analyzing the wavelength of light emitted by the mechanoluminescent material in real time, and obtaining a compressive stress-light wavelength curve of the mechanoluminescent material; Step A3, applying a linearly varying tensile force to the test block, collecting and analyzing the wavelength of light emitted by the mechanoluminescent material in real time, and obtaining a tensile stress-light wavelength curve of the mechanoluminescent material; Step A4: combine the compressive stress-light wavelength curve obtained in step A2 with the tensile stress-light wavelength curve obtained in step A3 to obtain a stress-wavelength curve of the mesoluminescent material.

3. The method for monitoring stress of pipe joints based on mechanoluminescent materials according to claim 2, characterized in that: In step A, the wavelength and stress value corresponding to the cracks on the test block are marked, and are appropriately reduced as warning values ​​for cracks on the pipe joint during actual pipe jacking construction.

4. The method for monitoring stress of pipe joints based on mechanoluminescent materials according to claim 1, characterized in that: In step B, the mesoluminescent material is sprayed at three locations on the inner wall of the pipe segment, and the three spraying locations are respectively located at the inner wall of the pipe segment near the two end joints and the middle part of the pipe segment.

5. The method for monitoring stress of pipe joints based on mechanoluminescent materials according to claim 1, characterized in that: After the force-induced luminescent material sprayed on the inner wall of the pipe segment in step B is cured, a layer of transparent resin material is sprayed on the force-induced luminescent material, and after curing, a transparent protective layer is formed outside the force-induced luminescent material.

6. The method for monitoring the stress of a pipe joint based on a mechanoluminescent material according to claim 1, characterized in that: In the step C, the wavelength of light emitted by the mechanoluminescent material on the inner wall of the pipe segment is collected and analyzed in real time along the circumferential direction at a certain rotational angular velocity to generate a wavelength-circumferential angle curve graph, and then the pipe segment stress-circumferential angle curve graph is obtained in combination with the stress-wavelength curve graph, thereby achieving real-time monitoring of the pipe segment stress.

7. The method for monitoring the stress of a pipe joint based on a mechanoluminescent material according to claim 6, characterized in that: In step C, an optical probe is installed on the inner wall of the pipe segment, and the optical probe is used to collect the light emitted by the mesoluminescent material and transmit it to the optical analysis system to analyze the wavelength of the light.

8. The method for monitoring the stress of a pipe joint based on a mechanoluminescent material according to claim 7, characterized in that: In the step C, a fixture is installed on the inner wall of the pipe segment, the fixture has a turntable, the rotation axis of the turntable is along the axial direction of the pipe segment, and the optical probe is installed on the turntable.

9. The method for monitoring stress of pipe joints based on mechanoluminescent materials according to claim 8, characterized in that: The optical probe and the mechanoluminescent material to be collected are located in the same section of the tube segment.

10. The method for monitoring the stress of a pipe joint based on a mechanoluminescent material according to claim 9, characterized in that: The fixture is connected to a computer via an angular velocity controller, and the computer controls the angular velocity of the optical probe driven by the turntable on the fixture.

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