Dry type splicing node interface force transmission sensing unit, system and method

Abstract

The invention belongs to the field of structural stress monitoring, and particularly relates to a dry type splicing node interface force transmission sensing unit, system and method, and the interface force transmission sensing unit comprises a base material, a first distributed optical fiber and a second distributed optical fiber; one side of the base material is a coupling surface; the first distributed optical fiber and the second distributed optical fiber are arranged in the base material along the length direction of the base material; the base material is provided with a cavity in the length direction, and the cavity surrounds the three faces, away from the coupling face, of the second distributed optical fiber. According to the interface force transmission sensing unit provided by the invention, the superimposed strain of the strain caused by the normal contact stress of the to-be-monitored interface and the tangential strain caused by the bending moment can be monitored through the first distributed optical fiber, and the tangential strain caused by the monitoring bending moment on the to-be-monitored interface can be monitored through the second distributed optical fiber; strain results monitored by the two optical fibers are calculated to obtain real normal and tangential contact stress distribution conditions.

Description

Technical Field

[0001] The present invention belongs to the field of structural stress monitoring, and in particular relates to a dry-type splicing node interface force transmission sensing unit, system and method. Background Art

[0002] Prefabricated structures have developed rapidly due to their significant advantages in energy conservation, emission reduction, and improved construction efficiency. As a key technology in prefabricated structures, accurate monitoring of the force transmission performance of dry-jointed nodes is essential to ensure the safety and functionality of the structure. However, unlike continuous section components that transmit stress through bending, dry-jointed nodes rely on contact at the node interface to transmit stress. This contact transmission method results in complex stress distribution on the interfaces of the node, and stress concentration is prone to occur in the node area.

[0003] Traditional strain gauges are large in size and can only monitor the stress state of a single measuring point, which cannot meet the needs of multi-interface stress sensing of dry splicing nodes. The emergence of distributed fiber optic sensing technology provides a new possibility to solve this problem. This technology uses optical fiber as a sensor, which can continuously monitor temperature and strain along the entire length of the fiber, and realize multi-point, distributed real-time monitoring of the structure. Distributed fiber optic sensing technology has the advantages of small size, strong anti-electromagnetic interference ability, corrosion resistance, and flexible installation. It is particularly suitable for multi-interface stress monitoring of complex structures such as dry splicing nodes.

[0004] At present, there are pressure sensors based on distributed optical fiber sensing technology. The strain monitored by these pressure sensors cannot accurately reflect the actual force transmission situation of the node interface. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a dry-type splicing node interface force transmission sensing unit, system and method which can still feedback the actual force transmission situation when subjected to axial force and bending moment force.

[0006] The present invention provides a dry-type splicing node interface force transmission sensing unit, comprising a substrate, a first distributed optical fiber and a second distributed optical fiber; One side of the substrate is a coupling surface, and the coupling surface is used to couple with the interface to be monitored; The first distributed optical fiber and the second distributed optical fiber are arranged in the substrate along the length direction of the substrate; A cavity is arranged on the substrate along the length direction, and the cavity surrounds three sides of the second distributed optical fiber away from the coupling surface.

[0007] Furthermore, the first distributed optical fiber and the second distributed optical fiber are at the same distance from the coupling surface.

[0008] Furthermore, the cavity penetrates through both ends of the substrate in the length direction.

[0009] Furthermore, the cross-section of the cavity is in a "U" shape, the opening side of the "U" shape faces the coupling surface, and the second distributed optical fiber is arranged in the middle of the "U" shape.

[0010] Furthermore, the coupling surface is a serrated structure.

[0011] Furthermore, the first distributed optical fiber and the second distributed optical fiber are two segments of the same optical fiber.

[0012] The present invention also provides an interface force transmission sensing system, including the above dry splicing joint interface force transmission sensing unit; Both the first distributed optical fiber and the second distributed optical fiber of the dry splicing joint interface force transmission sensing unit are connected with a distributed optical fiber demodulator, and the distributed optical fiber demodulator is connected with a data processing device.

[0013] Furthermore, when two or more dry splicing joint interface force transmission sensing units are connected in series, the first distributed optical fiber and the second distributed optical fiber of two or more dry splicing joint interface force transmission sensing units are connected in series in sequence, and the first distributed optical fiber and the second distributed optical fiber of the end dry splicing joint interface force transmission sensing unit are connected with the distributed optical fiber demodulator; When two or more groups of dry splicing joint interface force transmission sensing units are connected in parallel, the first distributed optical fiber and the second distributed optical fiber of each end dry splicing joint interface force transmission sensing unit are respectively connected with the distributed optical fiber demodulator; or, the first distributed optical fiber and the second distributed optical fiber of each end dry splicing joint interface force transmission sensing unit are connected end to end, and the first distributed optical fiber and the second distributed optical fiber at the terminal are connected with the distributed optical fiber demodulator.

[0014] The present invention also provides an interface force transmission sensing method, using the above interface force transmission sensing system; S1, install all dry splicing joint interface force transmission sensing units on the interface to be monitored; S2, the distributed optical fiber demodulator collects the strain data of the first distributed optical fiber and the second distributed optical fiber in all dry splicing joint interface force transmission sensing units; S3, the data processing device calculates the obtained strain data through a stress calculation model to obtain the normal contact stress and tangential contact stress of each dry splicing joint interface force transmission sensing unit. S4, obtain the normal stress distribution of the interface to be monitored according to the spatial position relationship between each normal contact stress and the corresponding dry splicing node interface force transmission sensing unit, obtain the tangential stress distribution of the interface to be monitored according to the spatial position relationship between each tangential contact stress and the corresponding dry splicing node interface force transmission sensing unit, and obtain the contact state of the interface to be monitored according to the normal stress distribution and the tangential stress distribution.

[0015] Furthermore, the stress calculation model includes a normal contact stress calculation model and a tangential contact stress calculation model; The normal contact stress calculation model is: ; In the formula, is the normal contact stress, For the first distributed optical fiber strain monitoring, is the strain monitored by the second distributed optical fiber, E is the elastic modulus of the substrate, is the substrate Poisson’s ratio; The tangential contact stress calculation model is: ; In the formula, is the tangential contact stress.

[0016] The beneficial effect of the present invention is that the dry-type splicing node interface force transmission sensing unit provided by the present invention arranges a first distributed optical fiber and a second distributed optical fiber in a substrate, and arranges a cavity in three directions of the second distributed optical fiber, so that the superimposed strain of the strain caused by the normal contact stress of the interface to be monitored and the tangential strain caused by the bending moment can be monitored by the first distributed optical fiber, and the tangential strain caused by the bending moment on the interface to be monitored can be monitored by the second distributed optical fiber. The strain results monitored by the two optical fibers are calculated to obtain the real normal contact stress, and the contact state and tangential stress of the interface to be monitored are obtained at the same time.

[0017] In addition, the dry splicing node interface force transmission sensing units can be networked, and by coordinating the coordinate positions of multiple dry splicing node interface force transmission sensing units, the contact status of each interface, the interface normal contact stress distribution and the interface tangential stress distribution on a large area of ​​the monitored interface can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Attached Figure 1 It is a structural schematic diagram of the dry-type splicing node interface force transmission sensing unit in the present invention; Attached Figure 2 It is a front view of the dry-type splicing node interface force transmission sensing unit in the present invention; Attached Figure 3 It is a schematic diagram of the network layout structure of the interface force transmission sensing system in the present invention; Attached Figure 4 It is a schematic diagram of the interface stress and strain of the interface to be monitored under the action of axial force in the present invention; Attached Figure 5 It is a schematic diagram of interface stress and strain of the interface to be monitored under the synergistic action of axial force and bending moment in the present invention; Attached Figure 6 A schematic diagram of complex stress distribution at the interface of a dry-jointed node in the present invention; Attached Figure 7 It is a structural schematic diagram of the interface force transmission sensing system in the present invention; Attached Figure 8 It is a schematic diagram of the flow of the interface force transmission sensing method in the present invention.

[0019] In the figure, 1-dry splicing node interface force transmission sensing unit; 101-substrate; 1011-coupling surface; 102-first distributed optical fiber; 103-second distributed optical fiber; 104-cavity; 2-distributed optical fiber demodulator; 3-data processing device; 4-interface to be monitored; 401-first component; 402-second component; 5-transmission optical fiber; 6-data transmission device; 7-computer; 8-mobile terminal. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0022] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0025] As attached Figure 1 -Attached Figure 8 As shown, the present invention provides a dry-type splicing node interface force transmission sensing unit 1, comprising a substrate 101, a first distributed optical fiber 102 and a second distributed optical fiber 103; One side of the substrate 101 is a coupling surface 1011, and the coupling surface 1011 is used to couple with the interface 4 to be monitored, so that the tangential stress of the interface 4 to be monitored can be transferred to the substrate 101; The first distributed optical fiber 102 and the second distributed optical fiber 103 are arranged in the substrate 101 along the length direction of the substrate 101. The first distributed optical fiber 102 and the second distributed optical fiber 103 are both used to monitor the strain in the substrate 101, wherein the first distributed optical fiber 102 is in close contact with the inner wall of the substrate 101, and is used to monitor the tangential strain generated by the substrate 101 when subjected to normal and tangential actions, and further can feedback the superimposed tangential strain generated by the interface 4 to be monitored when subjected to normal and tangential actions; A cavity 104 is provided on the substrate 101 along the length direction. The cavity 104 surrounds and is arranged on three sides of the second distributed optical fiber 103 away from the coupling surface 1011. The cavity 104 is arranged in this way to shield the strain caused by the normal action of the substrate 101 on the second distributed optical fiber 103, so that the substrate 101 only transmits the strain caused by the tangential action to the second distributed optical fiber 103, so that the second distributed optical fiber 103 monitors the substrate 101 when it is subjected to normal and tangential actions, shields the tangential strain generated after the normal action, and further can feedback the tangential strain generated by the interface 4 to be monitored when it is subjected to normal and tangential actions.

[0026] The dry splicing joint interface force transmission sensing unit 1 provided by the present invention arranges the first distributed optical fiber 102 and the second distributed optical fiber 103 in the base material 101, and arranges cavities 104 in three directions of the second distributed optical fiber 103. Furthermore, the first distributed optical fiber 102 can monitor the superimposed strain caused by the normal contact stress and the tangential strain caused by the bending moment on the interface 4 to be monitored, and the second distributed optical fiber 103 monitors the tangential strain caused by the monitoring bending moment on the interface 4 to be monitored. By calculating the strain results monitored by the two optical fibers, the true normal contact stress can be obtained, and at the same time, the contact state and tangential stress of the interface 4 to be monitored can be obtained.

[0027] In addition, the dry splicing joint interface force transmission sensing unit 1 can be networked, and in combination with the coordinate positions of multiple dry splicing joint interface force transmission sensing units 1, the contact states of each interface, the distribution of interface normal contact stress, and the distribution of interface tangential stress on a large area of the interface 4 to be monitored can be obtained.

[0028] In one embodiment, the first distributed optical fiber 102 and the second distributed optical fiber 103 are at the same distance from the coupling surface 1011, so as to ensure that the tangential strain data caused by the bending moment on the interface 4 to be monitored received by the first distributed optical fiber 102 and the second distributed optical fiber 103 are the same, and thus ensure the accuracy of the monitoring.

[0029] In one embodiment, the cavity 104 penetrates through both ends of the base material 101 in the length direction. With such a setting, the strain caused by the normal action in the entire length direction of the base material 101 on the second distributed optical fiber 103 can be completely shielded, the shielding effect can be improved, and thus the accuracy of the tangential stress feedback by the second distributed optical fiber 103 can be ensured.

[0030] Exemplarily, the cross-section of the cavity 104 continuously surrounds the upper left and right three sides of the second distributed optical fiber 103 (the lower side is the side close to the coupling surface 1011), such as a semi-circular arc. Any structure that can achieve the above is within the scope of the technical solutions protected by the embodiments of the invention. In one preferred embodiment, the cross-section of the cavity 104 is in a "U" shape, the opening side of the "U" shape faces the coupling surface 1011, and the second distributed optical fiber 103 is arranged in the middle of the "U" shape. With such a setting, the influence of the cavity 104 structure on the tangential strain caused by the bending moment can be reduced.

[0031] In one embodiment, the coupling surface 1011 is a serrated structure to enhance the friction between the base material 101 and the interface 4 to be monitored and improve the coupling effect. During specific installation, the coupling surface 1011 is bonded to the interface 4 to be monitored with glue. At this time, the serrated structure can improve the bonding effect of the glue. Taking the interface 4 to be monitored as a concrete material as an example, the serrated structure and the microporous structure of the concrete can greatly improve the bonding effect of the glue.

[0032] In one embodiment, the first distributed optical fiber 102 and the second distributed optical fiber 103 are two sections of the same optical fiber, which can simplify the connection with the distributed optical fiber demodulator 2. Of course, the first distributed optical fiber 102 and the second distributed optical fiber 103 can also be two independent optical fibers to simplify installation.

[0033] In one embodiment, the longitudinal length of the dry-type splicing node interface force transmission sensing unit 1 along the first distributed optical fiber 102 and the second distributed optical fiber 103 can be adjusted according to the size of the interface 4 to be monitored, and the width of the dry-type splicing node interface force transmission sensing unit 1 is much smaller than the width of the interface 4 to be monitored to ensure the monitoring effect; The present invention also provides an interface force transmission sensing system, comprising at least one dry splicing node interface force transmission sensing unit 1 as described above; The first distributed optical fiber 102 and the second distributed optical fiber 103 of the dry-type splicing node interface force transmission sensing unit 1 are both connected to a distributed optical fiber demodulator 2, which collects strain data of the first distributed optical fiber 102 and the second distributed optical fiber 103 in the dry-type splicing node interface force transmission sensing unit 1. Preferably, the first distributed optical fiber 102 and the second distributed optical fiber 103 are connected to the distributed optical fiber demodulator 2 through a transmission optical fiber 5, and the distributed optical fiber demodulator 2 is connected to a data processing device 3. The data processing device 3 is used to calculate and process the strain data collected by the distributed optical fiber demodulator 2 to obtain the normal contact stress and tangential contact stress of the interface 4 to be monitored; When the dry splicing node interface force transmission sensing unit 1 is networked, the normal stress distribution, tangential stress distribution and contact state can be obtained based on the normal contact stress and tangential contact stress of each dry splicing node interface force transmission sensing unit 1 and their corresponding spatial distribution relationship.

[0034] In one embodiment, the interface force transmission sensing system further includes a data transmission device 6 that is communicatively connected to the data processing device 3, and the data transmission device 6 is communicatively connected to the computer 7 and / or the mobile terminal 8. The acquired data can then be fed back to the user quickly and intuitively. The normal contact stress, tangential contact stress, normal stress distribution, tangential stress distribution and contact state of the interface 4 to be monitored are displayed on the terminal display device such as the computer 7 and / or the mobile terminal 8.

[0035] In one of the embodiments, when more than two dry-type splicing node interface force transmission sensing units 1 are arranged in series, the first distributed optical fibers 102 and the second distributed optical fibers 103 of the more than two dry-type splicing node interface force transmission sensing units 1 are sequentially connected in series, and the first distributed optical fibers 102 and the second distributed optical fibers 103 of the dry-type splicing node interface force transmission sensing units 1 at the ends are connected to the distributed optical fiber demodulator 2; When more than two groups of dry-type splicing node interface force transmission sensing units 1 are arranged in parallel, the first distributed optical fiber 102 and the second distributed optical fiber 103 of the dry-type splicing node interface force transmission sensing unit 1 at the end of each group are respectively connected to the distributed optical fiber demodulator 2; or, the first distributed optical fiber 102 and the second distributed optical fiber 103 of the dry-type splicing node interface force transmission sensing unit 1 at the end of each group are connected end to end, and the first distributed optical fiber 102 and the second distributed optical fiber 103 of the terminal are connected to the distributed optical fiber demodulator 2; At this time, when multiple dry-splicing node interface force transmission sensing units 1 are arranged in series and multiple groups are arranged in parallel, they are combined to form a network monitoring of the interface to be monitored 4, forming a surface monitoring network, covering the entire interface to be monitored 4. At this time, the interface to be monitored 4 can be a special-shaped surface or multiple interconnected or independent sections.

[0036] In one of the embodiments, the distributed optical fiber sensing technology used is optical frequency domain reflection technology, which can achieve a minimum spatial resolution of 0.68 mm, which is conducive to the monitoring of continuous stress and strain in space.

[0037] The present invention also provides an interface force transmission sensing method, using the above-mentioned networked interface force transmission sensing system; S1, installing all dry-type splicing node interface force transmission sensing units 1 on the interface to be monitored 4; S2, the distributed optical fiber demodulator 2 collects strain data of the first distributed optical fiber 102 and the second distributed optical fiber 103 in all dry-type splicing node interface force transmission sensing units 1; S3, the data processing device 3 calculates the obtained strain data through a stress calculation model to obtain the normal contact stress and the tangential contact stress of each dry splicing node interface force transmission sensing unit 1; S4, obtain the normal stress distribution of the interface 4 to be monitored according to the spatial position relationship between each normal contact stress and the corresponding dry splicing node interface force transmission sensing unit 1, obtain the tangential stress distribution of the interface 4 to be monitored according to the spatial position relationship between each tangential contact stress and the corresponding dry splicing node interface force transmission sensing unit 1, and obtain the contact state of the interface 4 to be monitored according to the normal stress distribution and the tangential stress distribution.

[0038] In one embodiment, the stress calculation model includes a normal contact stress calculation model and a tangential contact stress calculation model; The normal contact stress calculation model is: ; In the formula, is the normal contact stress, For the first distributed optical fiber strain monitoring, is the strain monitored by the second distributed optical fiber, E is the elastic modulus of the substrate, is the substrate Poisson’s ratio; The normal contact stress calculation model can be used to offset the tangential strain caused by the bending moment contained in the monitoring strain of the first distributed optical fiber 102, and obtain the normal contact stress; The tangential contact stress calculation model is: ; In the formula, is the tangential contact stress.

[0039] In one of the embodiments, when forming a network monitoring, a distributed optical fiber demodulator 2 is used to collect strain data of the first distributed optical fiber 102 and the second distributed optical fiber 103 in all dry-type splicing node interface force transmission sensing units 1; The data processing device 3 obtains the strain data of all dry splicing node interface force transmission sensing units 1, and calculates all normal contact stresses and tangential contact stresses according to the normal contact stress calculation model and the tangential contact stress calculation model, and stores the stress distribution data as normal contact stress distribution data according to the spatial correspondence between the corresponding measuring points and the points of the interface 4 to be monitored when all dry splicing node interface force transmission sensing units 1 are installed. and tangential stress distribution , and obtain the stress state of each interface.

[0040] In one embodiment, obtaining the contact state of the interface 4 to be monitored according to the normal stress distribution and the tangential stress distribution includes: Contact state is distributed through normal contact stress Discrimination, set the judgment threshold k, The value is lower than the threshold k, and the upper and lower interfaces of the interface 4 to be monitored are judged to be out of contact. The value greater than the threshold value k determines that the upper and lower interfaces of the monitored interface 4 are in contact and transmit contact stress.

[0041] Exemplarily, the force transmission sensing monitoring is performed on the dry-jointed node interface as the interface to be monitored 4, the interface to be monitored 4 includes a first component 401 and a second component 402 that are dry-jointed and bonded to each other, and the bonding surface of the first component 401 and the second component 402 is the interface to be monitored 4, specifically including the following steps: S11, according to the design of the dry splicing node, determine the specific size of the interface 4 to be monitored, specifically, refer to the attached Figure 6 , take the interface 4 to be monitored as an example with five interfaces connected in sequence, refer to the attached Figure 3 , a plurality of dry-type splicing node interface force transmission sensing units 1 are arranged at a spacing d to form a planar monitoring network, and the monitoring network covers all five interfaces; S12, installing the dry-type splicing node interface force transmission sensing unit 1 in the groove reserved for the dry-type splicing node interface to be tested; and networking the dry-type splicing node interface force transmission sensing unit 1 according to monitoring requirements to cover the interface to be tested; S21: using the distributed optical fiber demodulator 2 to collect strain data of the first distributed optical fiber 102 and the second distributed optical fiber 103 in all dry-type splicing node interface force transmission sensing units 1; S31: the data processing device 3 calculates the obtained strain data through a stress calculation model to obtain the normal contact stress and the tangential contact stress of each dry splicing node interface force transmission sensing unit 1; S41: obtaining the normal stress distribution of the interface 4 to be monitored according to the spatial position relationship between each normal contact stress and the corresponding dry splicing node interface force transmission sensing unit 1, obtaining the tangential stress distribution of the interface 4 to be monitored according to the spatial position relationship between each tangential contact stress and the corresponding dry splicing node interface force transmission sensing unit 1, and obtaining the contact state of the interface 4 to be monitored according to the normal stress distribution and the tangential stress distribution; S51: transmitting the data processed in S42 to a terminal display device (computer 7 or mobile terminal 8) via a data transmission device 6, and displaying the contact state of each node interface of the dry-joined node, the normal contact stress distribution of each node interface, and the tangential stress distribution of each node interface on the terminal display device; Furthermore, step S11 also includes: the height of the dry-type splicing node interface force transmission sensing unit 1 is slightly higher than the depth of the groove reserved for the dry-type splicing node interface, so as to ensure that the stress on the interface after the dry-type splicing node is assembled can be fully transmitted to the dry-type splicing node interface force transmission sensing unit 1; When the dry-type splicing node interface force transmission sensing unit 1 is installed, quick-drying glue is applied to one side of the coupling surface 1011 of the substrate 101, so that the dry-type splicing node interface force transmission sensing unit 1 is fully coupled with the concrete material of the dry-type splicing node; Furthermore, the normal contact stress in step S41 is and tangential stress The stress distribution data output after one-to-one correspondence with the interface space points is stored as normal contact stress distribution and tangential stress distribution ; Furthermore, the contact state of each interface of the node in step S41 is obtained by the normal contact stress distribution. Discrimination, set the judgment threshold k, If the value is lower than the threshold k, it is judged that the upper and lower interfaces of the dry splicing node at this point are out of contact. When the value is greater than the threshold k, it is determined that the upper and lower interfaces of the dry splicing node at this point are in contact and transmit contact stress.

[0042] Furthermore, in step S51, the contact result can be displayed on the terminal display device according to the contact determination result of each point on the interface, such as: the contact area is displayed in blue and the non-contact area is displayed in gray; Further, in step S51, the interface contact state of the dry assembly node is determined by the distribution of contact and non-contact areas and the stress distribution, such as: State 1: only one side of the interface is a non-contact area and the normal contact stress is concentrated on the other side, which can be determined as the interface is open on the side of the non-contact area; State 2: there are non-contact areas on both adjacent sides of the interface and the normal contact stress of the contact area is evenly distributed, which can be determined as the presence of misalignment on the interface; Furthermore, in step S51, the normal contact stress of each node interface and the tangential stress of each node interface can be displayed in different color levels to facilitate intuitive understanding of the interface stress state. Through the visual interface, monitoring personnel can intuitively observe the stress changes of the nodes during the assembly process, and whether there is any opening or misalignment.

[0043] The above is only an embodiment and does not limit the present invention in any way. Any person skilled in the art can use the above disclosed technical contents to make many possible changes, modifications or modifications to the technical solutions of the present invention into equivalent embodiments of equivalent changes without departing from the scope of the technical solutions of the present invention. Therefore, any simple modification, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the scope of protection of the technical solutions of the present invention.

Claims

1. A dry-type splicing node interface force transmission sensing unit, characterized in that it includes: A base material (101), a first distributed optical fiber (102), and a second distributed optical fiber (103); One side of the base material (101) is a coupling surface (1011), and the coupling surface (1011) is used for coupling with the interface to be monitored (4); The first distributed optical fiber (102) and the second distributed optical fiber (103) are arranged in the base material (101) along the length direction of the base material (101); A cavity (104) is arranged on the base material (101) along the length direction, and the cavity (104) surrounds three sides of the second distributed optical fiber (103) facing away from the coupling surface (1011).

2. The dry-type splicing node interface force transmission sensing unit according to claim 1 is characterized in that: The first distributed optical fiber (102) and the second distributed optical fiber (103) are at the same distance from the coupling surface (1011).

3. The dry-type splicing node interface force transmission sensing unit according to claim 1 is characterized in that: The cavity (104) penetrates through both ends of the base material (101) in the length direction.

4. The dry-type splicing node interface force transmission sensing unit according to claim 1 is characterized in that: The cross-section of the cavity (104) is in a "U" shape; The opening side of the "U" shape faces the coupling surface (1011), and the second distributed optical fiber (103) is arranged in the middle of the "U" shape.

5. The dry-type splicing node interface force transmission sensing unit according to claim 1 is characterized in that: The coupling surface (1011) is a serrated structure.

6. The dry-type splicing node interface force transmission sensing unit according to claim 1, characterized in that: The first distributed optical fiber (102) and the second distributed optical fiber (103) are two segments of the same optical fiber.

7. An interface force transmission sensing system, characterized in that: Comprising at least one dry splicing node interface force transmission sensing unit (1) as described in any one of claims 1-6; Distributed optical fiber demodulators (2) are connected to both the first distributed optical fiber (102) and the second distributed optical fiber (103) of the dry splicing node interface force transmission sensing unit (1), and the distributed optical fiber demodulators (2) are connected to a data processing device (3).

8. The interface force transmission sensing system according to claim 7, characterized in that When two or more dry splicing node interface force transmission sensing units (1) are connected in series, the first distributed optical fiber (102) and the second distributed optical fiber (103) of two or more dry splicing node interface force transmission sensing units (1) are connected in series in sequence, and the first distributed optical fiber (102) and the second distributed optical fiber (103) of the end dry splicing node interface force transmission sensing unit (1) are connected to the distributed optical fiber demodulator (2); When two or more groups of dry splicing node interface force transmission sensing units (1) are connected in parallel, the first distributed optical fiber (102) and the second distributed optical fiber (103) of each end dry splicing node interface force transmission sensing unit (1) are respectively connected to the distributed optical fiber demodulator (2); or, the first distributed optical fiber (102) and the second distributed optical fiber (103) of each end dry splicing node interface force transmission sensing unit (1) are connected end to end, and the first distributed optical fiber (102) and the second distributed optical fiber (103) at the terminal are connected to the distributed optical fiber demodulator (2).

9. A method for sensing interface force transmission, characterized in that: Using the interface force transmission sensing system as described in claim 8; S1, installing all the dry splicing node interface force transmission sensing units (1) on the interface to be monitored (4); S2, the distributed optical fiber demodulator (2) collects the strain data of the first distributed optical fiber (102) and the second distributed optical fiber (103) in all the dry splicing node interface force transmission sensing units (1); S3, the data processing device (3) calculates the obtained strain data through a stress calculation model to obtain the normal contact stress and the tangential contact stress of each dry splicing node interface force transmission sensing unit (1); S4, obtaining the normal stress distribution of the interface to be monitored (4) according to the spatial position relationship between each normal contact stress and the corresponding dry splicing node interface force transmission sensing unit (1), obtaining the tangential stress distribution of the interface to be monitored (4) according to the spatial position relationship between each tangential contact stress and the corresponding dry splicing node interface force transmission sensing unit (1), and obtaining the contact state of the interface to be monitored (4) according to the normal stress distribution and the tangential stress distribution.

10. The interface force sensing method according to claim 9, characterized in that: The stress calculation model includes a normal contact stress calculation model and a tangential contact stress calculation model; The normal contact stress calculation model is: ； In the formula, is the normal contact stress, For the first distributed optical fiber strain monitoring, is the strain monitored by the second distributed optical fiber, E is the elastic modulus of the substrate, is the substrate Poisson’s ratio; The tangential contact stress calculation model is: ； In the formula, is the tangential contact stress.

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