A simulation monitoring method for a non-contact array distributed optical fiber device

Abstract

The present invention discloses a non-contact array-type distributed optical fiber device, including a mounting base, the mounting base including a shock-absorbing base and a supporting device, at least one supporting device is arranged on the shock-absorbing base, and a plurality of connection winding points are arranged in a linear array along the axis of the supporting device above; it also includes a monitoring device, the monitoring device includes a sensing optical fiber and a Brillouin optical time-domain reflectometer device, the sensing optical fiber is arranged between two spaced, parallel, and opposite mounting bases, and is sequentially arranged at each connection winding point on the supporting device, forming a continuous layered structure; one end of the sensing optical fiber is electrically connected to the Brillouin optical time-domain reflectometer device. The present invention also discloses a simulation monitoring method of the device; the present application can effectively solve the problem of simulation monitoring of non-contact array distributed optical fiber acoustic wave testing technology, construct a database of voiceprint information of building structural components during the fracture process, and prepare for its application in safety monitoring of building structural components.

Description

Technical Field

[0001] The invention belongs to the technical field of structural health monitoring, and in particular relates to a simulation monitoring method for a non-contact array-type distributed optical fiber device. Background Art

[0002] With the planning and construction of a large number of urban infrastructure, people's requirements for the quality of construction projects are constantly increasing. Modern engineering is faced with many difficulties, high difficulty and large investment. The building structure is developing towards super-high-rise, large space and large span; therefore, people's safety requirements are gradually increasing. However, during the use of the building, due to many factors such as force, fatigue effect, environmental temperature and humidity, aging and corrosion, many safety accidents have shown many signs before they occur. Structural damage and reduced resistance performance will lead to catastrophic accidents.

[0003] Modern building structure monitoring is an important means of structural safety early warning, which is of great significance to civil engineering disciplines and engineering practice. On the one hand, monitoring of major projects is very effective in ensuring the safety and risk control of engineering projects. A large number of engineering accidents show that abnormalities can be found from monitoring data before accidents occur, so that early warning can be achieved. On the other hand, the development of civil engineering structure tests also requires continuous advancement of monitoring technology to meet more abundant and rigorous research needs.

[0004] In recent years, with the improvement of the full-life design requirements for building structures, new tasks and requirements have been put forward for the health monitoring of building structural components. The current building structural component health monitoring technology can be classified into contact monitoring equipment and non-contact monitoring equipment based on whether the monitoring equipment needs to contact the structure being tested. Among them, traditional contact monitoring methods, such as patch strain and vibration monitoring, have the disadvantages of difficult deployment, discrete monitoring points, and poor long-term monitoring reliability. For this reason, non-contact monitoring methods have emerged and become a hot spot in the research of structural monitoring technology. Traditional monitoring technologies such as ultrasonic flaw detection monitoring of steel structures and reflected wave low strain method for measuring pile foundation strength belong to the category of non-contact monitoring equipment. At present, ultrasonic testing is the most widely used non-destructive testing technology. The basic principle of ultrasonic testing of building structures is that when ultrasonic waves propagate in the material being tested, they will be affected by the acoustic properties and internal organizational changes of the material. The degree of damage to the test material can be understood by detecting the degree of influence of ultrasonic waves. However, traditional non-contact monitoring equipment such as ultrasound cannot detect the fracture and damage of components in progress in a timely manner, and cannot realize real-time monitoring of the condition of building components; and the measurement accuracy of its monitoring method is not high, and it cannot complete the accurate measurement of the fracture and damage of building components.

[0005] At present, there is no device or monitoring method for applying non-contact array distributed fiber optic acoustic wave testing technology to the monitoring of building structural components. In order to further promote the application of non-contact array distributed fiber optic acoustic wave testing technology in building structures, solve the problem of simulation monitoring of non-contact array distributed fiber optic acoustic wave testing technology, and build a database of acoustic wave frequencies and vibration soundprint information when different building materials are damaged or broken, it is necessary to design a non-contact array distributed fiber optic device. In addition, it is necessary to design a simulation monitoring method to guide the experiment and obtain the vibration soundprint information when different building materials are damaged or broken. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the main purpose of the present invention is to provide a non-contact array-type distributed optical fiber device with simple structure, strong anti-interference and high measurement accuracy. The present invention also provides a simulation monitoring method for the non-contact array-type distributed optical fiber device.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] In a first aspect, a non-contact array-type distributed optical fiber device comprises an installation base, wherein the installation base comprises a shock-absorbing base and a supporting device, wherein at least one supporting device is arranged on the shock-absorbing base, and a plurality of connection winding points are arranged above the supporting device in a linear array along its axis; further comprising a monitoring device, wherein the monitoring device comprises a sensing optical fiber and a Brillouin optical time-domain reflectometer device, wherein the sensing optical fiber is arranged between two spaced, parallel, and opposite installation bases, and is sequentially wound around each connection winding point arranged on the supporting device, forming a continuous layered structure; one end of the sensing optical fiber is electrically connected to the Brillouin optical time-domain reflectometer device.

[0009] Preferably, the supporting device is formed by connecting a plurality of threaded straight rods, a screw rod is arranged at the lower end of the threaded straight rod, a thread is arranged around the inner wall of the upper end, and adjacent threaded straight rods are fixedly connected by the screw rod and the thread.

[0010] Preferably, the shock-absorbing base comprises an upper fixing plate and a lower fixing plate, and a shock-absorbing layer is fixedly arranged between the upper fixing plate and the lower fixing plate.

[0011] Preferably, a plurality of shock absorbing devices are arranged inside the shock absorbing layer, and the shock absorbing devices are damping spring shock absorbers.

[0012] Preferably, the upper fixing plate, the shock absorbing layer and the lower fixing plate are all rectangular plates, the upper end surface of the upper fixing plate is provided with a plurality of threaded holes and is threadedly connected to the supporting device, the shock absorbing layer is provided with a plurality of through holes, the shock absorbing device is penetrated through the through holes, and the upper end of the shock absorbing device is fixedly connected to the upper fixing plate, and the lower end is fixedly connected to the lower fixing plate, and the lower end surface of the lower fixing plate is also evenly provided with a plurality of rubber pads.

[0013] Preferably, the upper part of the supporting device is also provided with a clamping mechanism matching the connection winding point, and the clamping mechanism includes a plurality of fixed brackets arranged at intervals from top to bottom, and the fixed brackets are provided with optical fiber card slots whose width directly matches the sensing optical fiber, and the sensing optical fiber is fixed on the supporting device through the fixed brackets.

[0014] Preferably, the number of the supporting devices is 1-6, the number of the fixing brackets is 1-60, the number of the shock absorbing devices is 2-8, and the number of the rubber pads is 2-8.

[0015] A second aspect: A simulation monitoring method according to the above-mentioned non-contact array distributed optical fiber device comprises the following steps:

[0016] 1) A non-contact array-type distributed optical fiber device is arranged around the structural component to be measured, and the sensing optical fiber on the non-contact array-type distributed optical fiber device is 5 cm-200 cm away from the structural component to be measured;

[0017] 2) Pressurize the structural component to be tested, and the structural component to be tested will break after being subjected to the pressure, and vibration soundprint information will be generated during the fracture process. The vibration soundprint information will be transmitted to the sensing optical fiber of the non-contact array distributed optical fiber device placed around the structural component to be tested. The sensing optical fiber will collect the vibration soundprint signal and transmit and store it to the Brillouin optical time domain reflectometer equipment.

[0018] Preferably, the arrangement method includes placing the structural component to be measured parallel to the outside of the sensing optical fiber, and the structural component to be measured is placed parallel to the sensing optical fiber.

[0019] Preferably, the arrangement method further comprises placing the structural component to be measured parallel to the middle of the sensing optical fiber, and the structural component to be measured is placed perpendicular to the sensing optical fiber.

[0020] Compared with the prior art, the present invention has at least the following advantages:

[0021] 1) The non-contact array-type distributed optical fiber device provided by the present invention avoids the pre-embedding of monitoring equipment during construction, reduces the construction difficulty, and avoids the change of the performance of the structural components due to the embedding of monitoring equipment, thereby improving the safety of the structural components and saving construction costs and time;

[0022] 2) The non-contact array-type distributed optical fiber device provided by the present invention can monitor the external data of existing building structures. By setting up the non-contact array-type distributed optical fiber device on the outside of the building components, the health monitoring of the existing building structure components can be realized without changing the internal structure of the building components. The monitoring device is of great significance to the safe service of the existing building structure components;

[0023] 3) The non-contact array-type distributed optical fiber device provided by the present invention can perform long-term real-time monitoring of the external data of existing building structures. When the signal of the vibration soundprint information in the non-contact array-type distributed optical fiber device changes, it can be determined that the structural component to be tested has an abnormal state (such as cracks, damage, and fractures), thereby realizing the monitoring of the safety service of the structural component to be tested.

[0024] 4) The simulation monitoring method of the non-contact array distributed optical fiber device provided by the present invention is distributed, high-precision, easy to test, low-cost, and highly practical. It collects and stores the vibration soundprint information of structural components when they are damaged or broken through the Brillouin optical time-domain reflectometer equipment, and conducts corresponding simulation monitoring experiments on different building materials. Through the simulation monitoring experiments, the actual situation on site is simulated to seek the correspondence between the vibration soundprint information and different materials, and construct a vibration soundprint information database, so as to prepare for the actual use of subsequent building components. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0026] Figure 1 This is a schematic diagram of the overall structure of the non-contact array-type distributed optical fiber device in this application;

[0027] Figure 2 This is a schematic diagram of the structure of the installation base in the non-contact array-type distributed optical fiber device in this application;

[0028] Figure 3 A layout state diagram of a non-contact array-type distributed optical fiber device in this application;

[0029] Figure 4 Another layout state diagram of the non-contact array-type distributed optical fiber device in this application;

[0030] Figure 5 Another layout state diagram of the non-contact array-type distributed optical fiber device in this application;

[0031] Figure 6 Another layout state diagram of the non-contact array-type distributed optical fiber device in this application;

[0032] Figure 7 Another layout state diagram of the non-contact array-type distributed optical fiber device in this application;

[0033] Figure 8 A graph of the soundprint of ambient (white) noise during the experiment provided in the embodiment of this application;

[0034] Fig. 9 This is a soundprint curve diagram of a 10 mm steel bar (model HRB500E) during the fracture process in the experiment provided in the embodiment of this application;

[0035] Fig.10 This is a soundprint curve diagram of a 12mm steel bar (model HRB500E) during the fracture process in the experiment provided in the embodiment of this application;

[0036] Fig.11 This is a soundprint curve diagram of a 10mm steel bar (model HRB400E) during the fracture process in the experiment provided in the embodiment of this application. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0038] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0039] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) 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.

[0040] In the present invention, the descriptions of "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.

[0041] In the description of the present invention, “plurality” means at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0042] 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 or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, 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.

[0043] In the following embodiments, the Brillouin optical time-domain reflectometer device used is the Brillouin optical time-domain reflectometer Ada-5034 developed by China Metallurgical Construction Research Institute Co., Ltd. and Beijing University of Posts and Telecommunications;

[0044] The sensing optical fiber used is FC (APC) - FC (APC) 30m single-mode optical fiber patch cord, which can be expanded to 10km according to the measurement range in the future. A single optical fiber is required to be continuous and uninterrupted;

[0045] The steel material fatigue testing machine used is a Sinco Tec 25-ton fatigue testing machine. The damage and fracture soundprint collection of different building materials is carried out in accordance with the national mandatory standard "Hot-rolled ribbed steel bars for reinforced concrete" (GB1499);

[0046] The present invention provides a non-contact array-type distributed optical fiber device, comprising an installation base, wherein the installation base comprises a shock-absorbing base and a supporting device, wherein at least one supporting device is arranged on the shock-absorbing base, and a plurality of connection winding points are arranged in a linear array along the axis of the supporting device above; the present invention also includes a monitoring device, wherein the monitoring device comprises a sensing optical fiber and a Brillouin optical time-domain reflectometer device, wherein the sensing optical fiber is arranged between two spaced, parallel, and opposite installation bases, and is sequentially wound around each connection winding point arranged on the supporting device, forming a continuous layered structure; and one end of the sensing optical fiber is electrically connected to the Brillouin optical time-domain reflectometer device.

[0047] Among them, the Brillouin optical time-domain reflectometer equipment has the ability to measure temperature and strain simultaneously. This is because a certain form of vibration exists inside the medium molecules, causing the medium's refractive index to fluctuate periodically with time and space, thereby generating a spontaneous acoustic wave field; when light is directed into the optical fiber medium, it is affected by the acoustic wave field and produces Brillouin scattering. Brillouin scattering in the optical fiber is manifested by the generation of Stokes waves that are down-shifted relative to the frequency of the incident pump wave, which can be regarded as a parametric interaction between the pump wave and the Stokes wave and the acoustic wave. The amount of Brillouin frequency shift produced by scattering is proportional to the speed of sound in the optical fiber:

[0048] f B =2nV A / η 1.1

[0049] The refractive index and sound velocity of the optical fiber are related to the temperature and stress of the optical fiber, which makes the Brillouin frequency shift f B As these parameters change, temperature and fiber strain will cause a linear shift in the Brillouin frequency, namely:

[0050]

[0051] Experiments have found that the Brillouin scattered light power increases linearly with the increase of temperature and decreases linearly with the increase of strain, that is, the Brillouin power can be expressed as:

[0052]

[0053] where f B (0) and P0 are the Brillouin frequency shift and power when T = 0℃ and strain is 0 (με), respectively. Since the effect of strain on the Brillouin scattered light power is much smaller than that of temperature, it can generally be ignored, and it is believed that the Brillouin scattered light power is only related to temperature. From equations 1.2 and 1.3, it can be seen that by detecting the optical power and frequency of Brillouin scattered light, the distribution information of temperature and strain along the sensing optical fiber can be obtained.

[0054] Therefore, the present application adopts Brillouin optical time domain reflectometer equipment to measure the strain of building structural components. The non-contact array distributed optical fiber device inherits the advantages of distributed optical fiber sensors and has high accuracy and spatial resolution for the measurement of a single distributed parameter.

[0055] Among them, for the collection of vibration soundprints of different building materials, the main focus is on collecting characteristic soundprints of different building materials when they are damaged or fractured, which include peak-to-average ratio / zero-crossing rate / signal duty cycle / average amplitude difference / kurtosis coefficient / skewness coefficient / peak ratio / trough ratio / ratio of long and short windows / ratio of primary and secondary peaks / center frequency / bandwidth / signal power / signal energy / inverted spectral coefficient 1 / inverted spectral coefficient 2 / shape parameter / effective value, etc.; or the empirical mode decomposition method is used to decompose the vibration mode of the composite material, and the features of the mode with a higher energy proportion of the fracture signal are expanded, and the features include modal frequency and intrinsic mode function.

[0056] The collected vibration soundprint information of different building materials will be used to form a feature database of the vibration soundprint information of different building materials when they are damaged or fractured, preparing for the application of the device in building components.

[0057] The shock-absorbing base includes an upper fixing plate and a lower fixing plate, and a shock-absorbing layer is fixedly arranged between the upper fixing plate and the lower fixing plate. The upper fixing plate, the shock-absorbing layer and the lower fixing plate are all rectangular plates, the upper end surface of the upper fixing plate is provided with a plurality of threaded holes and is threadedly connected to the supporting device, the shock-absorbing layer is provided with a plurality of through holes, the shock-absorbing device is penetrated and arranged in the through holes, and the upper end of the shock-absorbing device is fixedly connected to the upper fixing plate, and the lower end is fixedly connected to the lower fixing plate, and the lower end surface of the lower fixing plate is also evenly provided with a plurality of rubber pads; further, a plurality of shock-absorbing devices are also arranged inside the shock-absorbing layer, and the shock-absorbing device is a damping spring shock absorber.

[0058] The setting of the shock-absorbing base in this application reduces the influence of the base movement caused by environmental vibration on the upper monitoring equipment, thereby improving the accuracy of monitoring; assuming that the base motion equation is u g (t) = u g0 sinωt, due to the damping spring shock absorber set in the shock-absorbing layer, the displacement transmission rate of the shock-absorbing base movement to the upper monitoring equipment can be derived from formulas 1.11-1.17 Acceleration Transmittance Therefore, the total displacement of the monitoring device due to the movement of the shock-absorbing base It can be deduced from the formula that the damping spring shock absorber set in the shock-absorbing layer can be used to reduce the natural frequency of the monitoring equipment to achieve a better vibration isolation effect, thereby reducing the displacement error of the upper monitoring equipment and improving the accuracy of the monitoring data.

[0059] Basic displacement:

[0060] u g (t) = u g0 sinωt 1.11

[0061]

[0062] Displacement transmissibility:

[0063]

[0064] Acceleration transmissibility:

[0065]

[0066] Total displacement of upper monitoring device equipment:

[0067]

[0068] That is, the shock-absorbing base in the present application has a good vibration isolation effect.

[0069] The support device is formed by connecting a plurality of threaded straight rods, the lower end of the threaded straight rods is provided with a screw rod, the inner wall ring of the upper end is provided with a thread, and the adjacent threaded straight rods are fixedly connected by the screw rod and the thread. In the present application, the rigidity of the support device can be improved by adopting a combination of threaded straight rods. According to N cr =π 2 EA / λ 2 , the Euler critical force of the compressed rod system can be obtained, and the P-Δ second-order effect is considered at the same time. After calculation, it can be obtained that the compression effect of the upper monitoring equipment on the support device meets the measurement accuracy requirements. At the same time, considering the pre-tension between the sensing optical fibers, there are certain requirements for the stiffness of the support device. Therefore, threaded connection is used to improve the overall stiffness of the support device, reduce the displacement error of the top monitoring equipment, and thus improve the accuracy of the measurement results;

[0070] A simulation monitoring method according to the above-mentioned non-contact array distributed optical fiber device comprises the following steps:

[0071] 1) A non-contact array-type distributed optical fiber device is arranged around the structural component to be measured, and the sensing optical fiber on the non-contact array-type distributed optical fiber device is 5 cm-200 cm away from the structural component to be measured;

[0072] Specifically, the arrangement method includes placing the structural component to be measured parallel to the outside of the sensing optical fiber, and the structural component to be measured is placed parallel to the sensing optical fiber;

[0073] Or the arrangement method further includes placing the structural component to be measured parallel to the middle of the sensing optical fiber, and the structural component to be measured and the sensing optical fiber are placed vertically;

[0074] 2) Pressurize the structural component to be tested, and the structural component to be tested will break after being subjected to the pressure, and vibration soundprint information will be generated during the fracture process. The vibration soundprint information will be transmitted to the sensing optical fiber of the non-contact array distributed optical fiber device placed around the structural component to be tested. The sensing optical fiber will collect the vibration soundprint signal and transmit and store it to the Brillouin optical time domain reflectometer equipment.

[0075] Example 1

[0076] like Figure 1 and Figure 2 As shown, a non-contact array type distributed optical fiber device comprises a mounting base, the mounting base comprises a shock absorbing base 11 and a supporting device 12, at least one supporting device 12 is arranged on the shock absorbing base 11, and a plurality of connection winding points are evenly arranged in a linear array along the axis of the supporting device 12 above; and a monitoring device is also included, the monitoring device comprises a sensing optical fiber 21 and a Brillouin optical time domain reflectometer device 22, the sensing optical fiber 21 is arranged between two spaced, parallel and opposite mounting bases, and is sequentially wound around each connection winding point arranged on the supporting device 12, forming a continuous layered structure; specifically, the sensing optical fiber 21 is continuously and evenly wound back and forth around each connection winding point above the supporting device 12 (i.e., the winding points on the left and right sides) A line formed by the winding point is regarded as a detection point, and a sensing optical fiber wound back and forth is two detection points), and each sensing optical fiber 21 between the two mounting bases is a detection point; therefore, the non-contact array-type distributed optical fiber device of the present application forms multiple detection points in a continuous layered structure by setting the sensing optical fiber between two spaced, parallel, and opposite mounting bases, and winding each connection winding point set on the supporting device in sequence. The specific number of winding passes back and forth can be set by itself according to the actual monitoring needs and comprehensive consideration of cost control. The more passes are set, that is, the more detection points, the more accurate the data obtained by monitoring. One end of the sensing optical fiber 21 is electrically connected to the Brillouin optical time domain reflectometer device 22. When used specifically, a large amount of vibration soundprint information of different building materials is collected through the non-contact array-type distributed optical fiber device, and then a database of vibration soundprint information of different building materials is formed, which provides technical support for realizing dynamic and visual monitoring of building structural components and achieving information-based construction. It can be widely used in the monitoring and monitoring of various building structural components.

[0077] Preferably, again refer to Figure 1 and Figure 2In a preferred technical solution of this embodiment, the support device 12 is formed by connecting a plurality of threaded straight rods, a screw rod is provided at the lower end of the threaded straight rod, and a thread is provided on the inner wall ring of the upper end, and adjacent threaded straight rods are fixedly connected by the screw rod and the thread. Specifically, the support device is mainly composed of a plurality of threaded straight rods, and adjacent threaded straight rods are combined and connected by the screw rod and the thread; and then the length of the threaded straight rod is changed to adjust the support device, thereby adjusting the height of the monitoring equipment on the upper part of the support device, and then monitoring the building structure components of different heights.

[0078] Preferably, again refer to Figure 1 and Figure 2 In another preferred technical solution of the present embodiment, the shock-absorbing base 11 includes an upper fixing plate 111 and a lower fixing plate 112, and a shock-absorbing layer 113 is fixedly arranged between the upper fixing plate 111 and the lower fixing plate 112, wherein the upper fixing plate 111, the shock-absorbing layer 113 and the lower fixing plate 112 are all rectangular plates, and the upper end surface of the upper fixing plate 111 is provided with a plurality of threaded holes and is threadedly connected to the support device 12, and the upper fixing plate 111 is threadedly connected to the support device 12, so that the overall rigidity of the support device 12 is improved and the stiffness is reduced. The displacement error of the upper monitoring device is reduced, thereby improving the accuracy of the measurement results; a plurality of through holes are provided in the shock absorbing layer 113, and the shock absorbing device 1131 is provided through the through holes, and the upper end of the shock absorbing device 1131 is fixedly connected to the upper fixed plate 111, and the lower end is fixedly connected to the lower fixed plate 112, and a plurality of rubber pads (not shown in the figure) are evenly provided on the lower end surface of the lower fixed plate 112; wherein a plurality of shock absorbing devices 1131 are also provided inside the shock absorbing layer 113, and the shock absorbing device 1131 is a damping spring shock absorber. This setting reduces the natural frequency of the monitoring device to achieve a better vibration isolation effect by providing a damping spring shock absorber inside the shock absorbing layer, thereby reducing the displacement error of the monitoring device and improving the accuracy of the monitoring data; by evenly providing a plurality of rubber pads on the lower end surface of the lower fixed plate, the natural frequency of the monitoring device is further reduced, providing technical support for further improving the accuracy of the monitoring data.

[0079] Example 2

[0080] Based on Example 1, refer again to Figure 1 and Figure 2, wherein the upper part of the support device 12 is also provided with a clamping mechanism that matches the connection winding point, and the clamping mechanism includes a plurality of fixed brackets 31 arranged at intervals from top to bottom, and the fixed brackets 31 are provided with optical fiber slots 32 whose width directly matches the sensing optical fiber 21, and the sensing optical fiber 21 is fixedly arranged on the support device 12 through the fixed brackets 31. Specifically, the sensing optical fiber is fixed to the support device through the fixed bracket, and the sensing optical fiber can be combed to avoid the entanglement of the sensing optical fiber; and the setting of the optical fiber slot can avoid the loose connection due to its own gravity, thereby ensuring that the sensing optical fiber maintains a certain tension between the support devices, thereby providing technical support for further improving the accuracy of the monitoring data.

[0081] Preferably, in a preferred technical scheme in the present embodiment, the number of supporting devices 12 is 1-6, the number of fixed brackets 31 is 1-60, the number of shock absorbing devices 1131 is 2-8, and the number of rubber pads is 2-8; further preferably, the number of supporting devices 12 is 2-4, the number of fixed brackets 31 is 3-30, the number of shock absorbing devices 1131 is 4-6, and the number of rubber pads is 4-6. This arrangement can maintain the non-contact array distributed optical fiber device at a lower production cost while ensuring the accuracy of the monitoring data.

[0082] The simulation monitoring method based on a non-contact array distributed optical fiber device comprises the following steps:

[0083] 1) A non-contact array-type distributed optical fiber device is arranged around the structural component to be measured, and the sensing optical fiber on the non-contact array-type distributed optical fiber device is 5 cm-200 cm away from the structural component to be measured;

[0084] 2) Pressurize the structural component to be tested, and the structural component to be tested will break after being subjected to the pressure, and vibration soundprint information will be generated during the fracture process. The vibration soundprint information will be transmitted to the sensing optical fiber of the non-contact array distributed optical fiber device placed around the structural component to be tested. The sensing optical fiber will collect the vibration soundprint signal and transmit and store it to the Brillouin optical time domain reflectometer equipment.

[0085] Specifically, the non-contact array-type distributed optical fiber device in the present application can be adjusted accordingly according to the needs of actual use, including the number of mounting bases, the number of support devices provided on the shock-absorbing base, and the number of fixed brackets provided on the axial surface of the upper part of the support device; specifically, for some long strip-shaped structural members to be tested, such as the cable dome of a large public building and the prestressed steel strand grid of a large glass curtain wall, the structural member to be tested can be placed parallel to the outside of the sensing optical fiber, and the structural member to be tested can be placed parallel to the sensing optical fiber; specifically, Figure 3 , Figure 4 and Figure 5 As shown, the sensing optical fiber is wound between two spaced, parallel, and opposite mounting bases, where the mounting bases are generally rectangular frames with short sides relatively parallel to each other, and passes through the connection and winding points at the upper ends of the two supporting devices on the mounting bases to form an array linear structure, thus forming a monitoring sensor network;

[0086] For some structural components to be tested that occupy a large space, such as the steel strand cables of a cable-stayed bridge, the structural components to be tested can be placed parallel to the sensing optical fibers, and the structural components to be tested and the sensing optical fibers can be placed vertically. Figure 6 and Figure 7 As shown, the sensing optical fiber is wound between two spaced, parallel, and opposite mounting bases, where the mounting bases are generally rectangular frames with their long sides relatively parallel, and passes through the connection winding points at the upper ends of multiple supporting devices on the mounting bases to form an array linear structure, constituting a monitoring sensor network; the present application conducts laboratory and field verification of the non-contact array distributed optical fiber device, specifically:

[0087] Laboratory Experiment 1:

[0088] In the laboratory, the non-contact array-type distributed optical fiber device provided by the present application is subjected to a simulation test in the laboratory: specifically, a 10mm steel bar (model HRB500E) is fixed on a steel bar material fatigue testing machine, and the non-contact array-type distributed optical fiber device of the present application is placed on the side of the steel bar material fatigue testing machine, and the distance between the structural component (steel bar) to be tested and the side sensing optical fiber is 10cm (that is, the steel bar is placed on the side of the sensing optical fiber), and the power device of the steel bar material fatigue testing machine is turned on to drive the steel bar to be pulled in the upward and downward directions. The steel bar breaks after being subjected to pressure, and energy (vibration / sound) is released during the fracture to generate vibration soundprint information at the time of fracture. The vibration is transmitted to the sensing optical fiber on the side of the steel bar, and the sensing optical fiber collects the vibration / sound signal, transmits and stores it to the Brillouin optical time domain reflectometer equipment. The curve of the steel bar at the moment of fracture is as shown in FIG. Fig. 9 As shown, Figure 8 is the ambient (white) noise curve. By comparison Figure 8 and Fig. 9 It can be seen that there is an obvious signal change in the fracture process, and the process is reproducible and repeatable, with a consistency of up to 98% during repetition.

[0089] The supporting device of the non-contact array type distributed optical fiber device used in the experiment is provided with 6 connection winding points, and each mounting base is provided with a supporting device, as shown in FIG. Figure 3 shown.

[0090] The same test method was used to conduct simulation tests on 12mm steel bars (model HRB500E) and 10mm steel bars (model HRB400E). The results are as follows: Fig.10 and Fig.11 As shown, by comparison Figure 8 and Fig.10 , Fig.11 It can be seen that there is an obvious signal change in the fracture process, and the process is reproducible and repeatable, with a consistency of up to 98% during repetition.

[0091] Laboratory Experiment 2:

[0092] The non-contact array-type distributed optical fiber device provided by the present application was subjected to a simulation test in a laboratory: 10 mm steel bars (model HRB500E), 12 mm steel bars (model HRB500E), and 10 mm steel bars (model HRB400E) were fixed on a steel bar material fatigue testing machine, and the non-contact array-type distributed optical fiber device of the present application was placed on the side of the steel bar material fatigue testing machine, and the distance between the structural member (steel) to be tested and the sensing optical fiber on both sides was 10 cm (that is, the steel bar was placed in the middle of the sensing optical fiber), and the power device of the steel bar material fatigue testing machine was turned on. , so that it drives the steel bar to be pulled in both upward and downward directions. The steel bar breaks after being subjected to pressure, and the energy (vibration / sound) released during the fracture produces vibration soundprint information at the time of fracture. The vibration is transmitted to the sensing optical fiber on the side of the steel bar. The sensing optical fiber will collect the vibration / sound signal, transmit and store it to the Brillouin optical time domain reflectometer device; the curve of the steel bar at the moment of fracture is basically consistent with the vibration soundprint information generated by the 10mm steel bar (model HRB500E), 12mm steel bar (model HRB500E), and 10mm steel bar (model HRB400E) in laboratory experiment 1 when they break.

[0093] The non-contact array type distributed optical fiber device used in this experiment is provided with 6 connection winding points on the support device, and each mounting base is provided with 2 support devices, as shown in the following figure. Figure 6 shown.

[0094] Laboratory comparative example 1

[0095] The experimental method in this comparative example 1 is the same as that in the laboratory experiment 1. The non-contact array-type distributed optical fiber device in this comparative example is basically the same as that in the laboratory experiment 1, except that no shock-absorbing layer is provided in the shock-absorbing base of the non-contact array-type distributed optical fiber device. The test results are as follows: the steel bars (10mm steel bars (model HRB500E), 12mm steel bars (model HRB500E), 10mm steel bars (model HRB400E) have signal changes during the fracture process, but the amplitude of the signal change is significantly lower than that of the shock-absorbing base with a shock-absorbing layer, and the environmental vibration transmitted from the base is not effectively filtered, and it is difficult to effectively detect the non-contact vibration soundprint signal. Therefore, it is not suitable for monitoring when the structural member to be tested is damaged or cracked.

[0096] Laboratory Comparative Example 2

[0097] The experimental method in this comparative example 1 is the same as that in the laboratory experiment 1. The non-contact array-type distributed optical fiber device in this comparative example is basically the same as that in the laboratory experiment 1, except that only 1, 2, 3, 4, and 5 connection and winding points are set on the supporting device of the non-contact array-type distributed optical fiber device; the detection results are as follows: the steel bars (10mm steel bars (model HRB500E), 12mm steel bars (model HRB500E), and 10mm steel bars (model HRB400E) have signal changes during the fracture process, and with the increase of the connection and winding points (the increase of the detection points), the detection signal range of the vibration signal monitored on the Brillouin optical time domain reflectometer device is wider, and the intensity is enhanced to a certain extent. The results reflect the sensitivity and effectiveness of the array optical fiber in collecting non-contact vibration signals compared with a single unwound optical fiber (single detection point).

[0098] Through the above simulation experiments, it is verified that the non-contact array-type distributed optical fiber device is capable of collecting vibration soundprint information of different building materials (rebars, steel strands, etc.) during damage and fracture processes, and the collection information of the vibration soundprint information for different building materials is repeatable, indicating that the scheme of using the non-contact array-type distributed optical fiber device to monitor different building materials is feasible and reliable; at the same time, the non-contact array-type distributed optical fiber device provides technical support for establishing a comprehensive and complete failure soundprint database (vibration soundprint information of different building materials in abnormal states such as cracks, damage and fracture).

[0099] The above are only preferred specific embodiments of the present invention, but the protection scope of the invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for simulating monitoring of a non-contact array distributed optical fiber device, characterized in that: The method comprises the following steps: 1) arranging a non-contact array-type distributed optical fiber device around the structural component to be measured, wherein the sensing optical fiber on the non-contact array-type distributed optical fiber device is 5 cm to 200 cm away from the structural component to be measured; 2) Pressurizing the structural component to be tested, the structural component to be tested will break after being subjected to the pressure, and vibration soundprint information will be generated during the breaking process, and the vibration soundprint information will be transmitted to the sensing optical fiber of the non-contact array distributed optical fiber device placed around the structural component to be tested, and the sensing optical fiber will collect the vibration soundprint signal and transmit and store it to the Brillouin optical time domain reflectometer device; The non-contact array-type distributed optical fiber device comprises a mounting base, wherein the mounting base comprises a shock-absorbing base and a supporting device, wherein at least one supporting device is arranged on the shock-absorbing base, and a plurality of connection and winding points are arranged above the supporting device in a linear array along its axis; the non-contact array-type distributed optical fiber device comprises a monitoring device, wherein the monitoring device comprises a sensing optical fiber and a Brillouin optical time-domain reflectometer device, wherein the sensing optical fiber is arranged between two spaced, parallel, and opposite mounting bases, and is sequentially wound around each connection and winding point arranged on the supporting device, forming a continuous layered structure; and one end of the sensing optical fiber is electrically connected to the Brillouin optical time-domain reflectometer device.

2. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 1, characterized in that: The support device is formed by connecting a plurality of threaded straight rods, wherein a screw rod is arranged at the lower end of the threaded straight rod, and a thread is arranged around the inner wall of the upper end, and adjacent threaded straight rods are fixedly connected by the screw rod and the thread.

3. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 1 or 2, characterized in that: The shock-absorbing base comprises an upper fixing plate and a lower fixing plate, and a shock-absorbing layer is fixedly arranged between the upper fixing plate and the lower fixing plate.

4. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 3, characterized in that: A plurality of shock absorbing devices are also arranged inside the shock absorbing layer, and the shock absorbing devices are damping spring shock absorbers.

5. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 4, characterized in that: The upper fixing plate, the shock absorbing layer and the lower fixing plate are all rectangular plates. The upper end surface of the upper fixing plate is provided with a plurality of threaded holes and is threadedly connected to the supporting device. The shock absorbing layer is provided with a plurality of through holes. The shock absorbing device is penetrated through the through holes. The upper end of the shock absorbing device is fixedly connected to the upper fixing plate, and the lower end is fixedly connected to the lower fixing plate. The lower end surface of the lower fixing plate is also evenly provided with a plurality of rubber pads.

6. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 5, characterized in that: The upper part of the support device is also provided with a clamping mechanism matching the connection winding point, and the clamping mechanism includes a plurality of fixed brackets arranged at intervals from top to bottom, and the fixed brackets are provided with optical fiber card slots whose width directly matches the sensing optical fiber, and the sensing optical fiber is fixed on the support device through the fixed brackets.

7. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 6, characterized in that: The number of the supporting devices is 1-6, the number of the fixing brackets is 1-60, the number of the shock absorbing devices is 2-8, and the number of the rubber pads is 2-8.

8. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 1, characterized in that: The arrangement method includes placing the structural component to be measured parallel to the outer side of the sensing optical fiber, and the structural component to be measured is placed parallel to the sensing optical fiber.

9. The simulation monitoring method of the non-contact array distributed optical fiber device according to claim 1, characterized in that: The arrangement method further includes placing the structural component to be measured parallel to the middle of the sensing optical fiber, and the structural component to be measured is placed vertically to the sensing optical fiber.

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