Mine filling body health monitoring system and monitoring method based on carbon fiber composite material sensor

Abstract

The invention relates to the technical field of mine safety and filling mining, in particular to a mine filling body health monitoring system and method based on a carbon fiber composite material sensor. According to the method, the carbon fibers are doped into the filling material to manufacture the carbon fiber composite material sensor, the resistivity condition of the filling body is monitored through the signal transmission system, and then the damage condition of the filling body is obtained based on the established relation between the resistivity and the damage coefficient. The problem caused by implanting a traditional sensor into the filling body is solved, and the stability and strength of the filling body are basically not affected. The carbon fiber doping process and the filling material preparation process are unified, and the filling operation difficulty cannot be increased; and sensor installation work does not need to be carried out behind the working face, so that efficiency is improved, normal production is not hindered, production safety is guaranteed, and health monitoring of the underground coal mine filling materials is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of mine safety and filling mining, and in particular to a mine filling body health monitoring system and a monitoring method based on a carbon fiber composite material sensor. Background Art

[0002] Backfill mining has been widely used in the field of coal mining because of its remarkable effects in controlling the movement of overburden and reducing damage to surface buildings and water bodies. However, the structure and integrity of the backfill material are often affected by the preparation process and technology, resulting in defects such as voids and microcracks inside the backfill material, which in turn affects its overall strength. In particular, when the backfill material bears a large load from the overburden strata and is superimposed with the vibration dynamic load caused by rock strata breakage and blasting, the backfill material is very likely to become damaged and unstable, posing a serious threat to mine safety production. Therefore, monitoring the structural health of the backfill body and preventing disasters caused by sudden damage to the backfill material are extremely important for ensuring coal mine safety production.

[0003] At present, stress sensors and displacement sensors are mainly used for health monitoring of underground filling materials. These devices are mainly composed of resistive sensors and attached communication networks. By fixing resistive sensors inside or on the surface of the filling materials, parameters such as stress, displacement and deformation of the rock mass can be measured to evaluate the health of the filling materials. However, the underground environment is in a state of high stress, high heat and humidity for a long time, which can easily change the material and device performance of the sensor, causing a certain deviation between the sensor output signal and the actual value, making it difficult to obtain real and effective data during long-term measurements.

[0004] In addition, the installation of monitoring equipment is mainly carried out behind the working face. Since the filling material needs a certain amount of time to solidify, it is difficult to install it directly when pouring the filling material. Coal miners need to enter the goaf to install it after the filling material solidifies. As the coal mine working face continues to work, the longer the installation time is delayed, the greater the distance the workers will enter the goaf when installing the equipment, and the greater the safety risks they face.

[0005] The existing health monitoring methods for underground filling materials have obvious shortcomings and deficiencies: there is a risk of failure of monitoring equipment after long-term use, and due to the limitation of sensor size, the monitoring range is small, making it difficult to monitor the health of the entire filling material; the installation of monitoring equipment includes multiple processes such as drilling, installation, and plugging holes, and construction drilling will destroy the integrity of the filling material; in addition, special personnel need to be arranged to install monitoring equipment behind the working face, which is cumbersome to operate, affects production efficiency, and poses certain safety risks.

[0006] Therefore, the prior art needs to be further improved and developed. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a mine filling body health monitoring system and monitoring method based on carbon fiber composite material sensors to monitor the stability of underground filling materials and prevent safety accidents caused by damage and instability of underground filling materials.

[0008] In order to solve the above technical problems, the solution of the present invention includes:

[0009] A mine filling body health monitoring system based on a carbon fiber composite material sensor comprises a carbon fiber composite material sensor and a signal transmission system arranged underground; the carbon fiber composite material sensor comprises carbon fiber, filling material, an inert electrode IN1, an inert electrode IN2, an armored cable and a data collector; the inert electrode IN1 and the inert electrode IN2 are arranged in the carbon fiber filling body; the tails of the inert electrode IN1 and the inert electrode IN2 are connected to the armored cable, and the armored cable is connected to the data collector; the data collector comprises a bridge circuit, a signal amplification module, an analog-to-digital conversion module, and an RS485 communication module connected in sequence; the signal transmission system comprises an underground ring network switch, a ground ring network switch, and a monitoring host; the underground ring network switch is connected to the data collector, and the data collector converts a voltage signal into a digital signal and communicates with the underground ring network switch; the ground ring network switch is connected to the underground ring network switch; the monitoring host is communicatively connected to the ground ring network switch.

[0010] Preferably, the circuit bridge includes a first socket, a second socket, a first resistor, a second resistor, a third resistor and an AC power supply; the inert electrode IN1 is connected to the second socket, and the inert electrode IN2 is connected to the first socket; the second resistor is connected in series with the first socket and the second socket to form a first branch, the first resistor is connected in series with the third resistor to form a second branch, the first branch and the second branch are connected in parallel, and the connection points of the first branch and the second branch are respectively connected to the AC power supply AC; a first connecting line is provided on the first branch between the second resistor and the second socket, and the first connecting line is connected to the corresponding end circuit of the signal amplification module, and a second connecting line is provided on the second branch between the first resistor and the third resistor, and the second connecting line is connected to the corresponding end circuit of the signal amplification module.

[0011] Preferably, the signal amplification module is powered by an AC power supply VCC and is connected to a ground GND, and the output terminal V_IN is connected to ports b1 - b8 of the analog-to-digital conversion module.

[0012] Preferably, the analog-to-digital conversion module is powered by an AC power supply VCC and is connected to a ground GND; the analog-to-digital conversion module converts a voltage signal into a digital signal and is communicatively connected to an RS485 communication module.

[0013] Preferably, the RS485 communication module is powered by an AC power supply VCC, and is connected to a ground GND, and transmits resistance information to an underground ring network switch.

[0014] Preferably, the signal transmission system also includes a monitoring standby machine and a Web publishing machine; the monitoring standby machine and the Web publishing machine are communicatively connected to a ground ring network switch.

[0015] The present invention provides a mine filling body health monitoring method based on a carbon fiber composite material sensor, using the mine filling body health monitoring system based on a carbon fiber composite material sensor as described above, comprising the following steps:

[0016] Step 1: Fully mix carbon fiber, fly ash, gangue powder and cement materials to prepare carbon fiber composite filling material slurry;

[0017] Step 2: The carbon fiber composite filling material slurry is transported to a predetermined position underground through a pipeline for pouring. After pouring, multiple sets of inert electrodes IN1 and IN2 are arranged in the monitoring area; the multiple sets of inert electrodes IN1 and IN2 are connected to the data collector through armored cables;

[0018] After the carbon fiber filling body is cured for a certain age, the resistivity of the carbon fiber filling body is automatically collected through the data collector, and the data collector transmits the collected resistivity information to the monitoring host through the underground ring network switch and the ground ring network switch;

[0019] Step 3: While pouring the carbon fiber composite filling material slurry, take part of the carbon fiber composite filling material slurry to make a carbon fiber filling body sample, and carry out physical and mechanical tests after a certain curing period, record the resistivity of the carbon fiber filling body when it is not damaged and the resistivity when it is completely damaged, and use acoustic emission technology to monitor the cumulative ringing coefficient of acoustic emission, based on which the damage coefficient of the carbon fiber filling body is calculated, and the relationship between the damage coefficient and resistivity of the carbon fiber filling body is established;

[0020] Step 4: The monitoring host receives resistivity information in real time, and converts the resistivity into a corresponding damage coefficient based on the carbon fiber filler damage coefficient-resistivity relationship established in step 3; and determines the degree of damage to the carbon fiber filler based on the damage coefficient.

[0021] Preferably, in step 1, the water content information of the goaf is obtained, and the carbon fiber content is determined based on the water content information of the goaf, so that the influence of conductive ions on the resistivity is much smaller than that of carbon fibers, even if the influence of water on the resistivity of the carbon fiber filling body can be almost ignored.

[0022] Preferably, in step 2, multiple groups of inert electrodes IN1 and inert electrodes IN2 are arranged in a straight line, and the number of inert electrodes IN1 and inert electrodes IN2 is selected according to the monitoring accuracy requirement.

[0023] Preferably, in step 4, the damage degree of the carbon fiber filler is judged based on the damage coefficient and it is determined whether to issue an early warning instruction, and the threshold of the early warning instruction is set at the front of the resistivity surge area of ​​the carbon fiber filler damage coefficient-resistivity relationship curve.

[0024] Beneficial technical effects of the present invention: The present invention solves the problem of implanting traditional sensors into the filling body (reduced destructive strength of the filling body), and basically does not affect the stability and strength of the filling body. The process of doping carbon fiber is unified with the process of preparing the filling material, which will not increase the difficulty of the filling operation; and there is no need to install sensors behind the working surface, which improves efficiency, does not hinder normal production, ensures production safety, and realizes the health monitoring of filling materials in coal mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the principle of the carbon fiber composite material sensor in the present invention;

[0026] Figure 2 It is a schematic diagram of the internal structure of the carbon fiber composite material sensor of the present invention;

[0027] Figure 3 This is a schematic diagram of the transmission of the filling material health self-sensing information in the present invention;

[0028] Figure 4 It is a schematic diagram of the process of the method for monitoring the structural health of filling materials in underground coal mines using the carbon fiber composite material sensor of the present invention;

[0029] Figure 5 It is a structural schematic diagram of an embodiment of health monitoring of lane filling materials in the present invention;

[0030] In the figure: carbon fiber composite material sensor-A, signal transmission system-B, filling body / tunnel side support wall-101, armored cable-102, first inert electrode-IN1, second inert electrode-IN2, data collector-2, first socket-J1, second socket-J2, circuit bridge-201, first resistor-R1, second resistor-R2, third resistor-R3, AC power supply-AC, signal amplification module-202, analog-to-digital conversion module-203, RS485 communication module-204, AC power-VCC, ground-GND, output end-V_IN, underground ring network switch-3, ground ring network switch-4, monitoring host-5, monitoring standby machine-6, Web publishing-7, goaf-8, hydraulic support-9, coal seam-10. DETAILED DESCRIPTION

[0031] In order to better understand the technical content of the present invention, specific embodiments are cited and described as follows in conjunction with the accompanying drawings. In the present invention, various aspects of the present invention are described with reference to the accompanying drawings, in which many illustrative embodiments are shown. The embodiments of the present invention are not limited to those described in the accompanying drawings. It should be understood that the present invention is implemented by any of the various concepts and embodiments introduced above, as well as the concepts and implementations described in detail below, because the concepts and embodiments disclosed in the present invention are not limited to any implementation. In addition, some aspects disclosed in the present invention can be used alone or in any appropriate combination with other aspects disclosed in the present invention.

[0032] The monitoring principle of carbon fiber composite material sensor is as follows Figure 1 As shown in the figure, the conductive paths inside the filling material include ionic conduction, electronic conduction and hole conduction, with ionic conduction being the main one; however, the ionic conduction path is greatly affected by factors such as water and temperature, which will cause the resistivity of the filling material to be unstable. When a sufficient amount of carbon fiber is added to the filling material, the carbon fiber conductive path formed inside it will replace the original ionic conductive path; when cracks appear in the carbon fiber filling material, the carbon fiber near the cracks is broken or the carbon fiber overlap point is detached, destroying the original carbon fiber conductive path and causing its resistivity to rise rapidly; therefore, groups of electrodes can be arranged in the filling body and the resistivity changes in the filling area can be monitored to achieve structural health monitoring of the filling body.

[0033] Based on this, the present invention proposes a mine filling body health monitoring system based on carbon fiber composite material sensors, such as Figure 2-Figure 3 As shown, it includes a carbon fiber composite material sensor A and a signal transmission system B arranged underground;

[0034] The carbon fiber composite material sensor A comprises carbon fiber, filling material, inert electrode IN1, inert electrode IN2, armored cable 102 and data collector 2; the filling material doped with carbon fiber is poured in the area to be monitored to form a carbon fiber filling body 101, and the inert electrode IN1 and inert electrode IN2 are arranged at different positions of the predetermined monitoring area of ​​the carbon fiber filling body 101; the tails of the inert electrode IN1 and inert electrode IN2 are connected to the armored cable 102, and the armored cable 102 is connected to the data collector 2;

[0035] The data collector 2 includes a bridge circuit 201, a signal amplification module 202, an analog-to-digital conversion module 203, and an RS485 communication module 204;

[0036] The circuit bridge 201 includes a first socket J1, a second socket J2, a first resistor R1, a second resistor R2, a third resistor R3 and an AC power source AC; the inertial electrode IN1 and the inertial electrode IN2 are connected to the bridge circuit 201 through the armored cable 102, wherein the inertial electrode IN1 is connected to the second socket J2, and the inertial electrode IN2 is connected to the first socket J1; the second resistor R2 is connected in series with the first socket J1 and the second socket J2 to form a first branch, the first resistor R1 is connected in series with the third resistor R3 to form a second branch, the first branch and the second branch are connected in parallel, and the connection points of the first branch and the second branch are respectively connected to the AC power source AC; a first connecting line is provided on the first branch between the second resistor R2 and the second socket J2, and the first connecting line is connected to the corresponding end circuit of the signal amplification module 202, and a second connecting line is provided on the second branch between the first resistor R1 and the third resistor R3, and the second connecting line is connected to the corresponding end circuit of the signal amplification module 202;

[0037] The signal amplification module 202 is powered by an AC power source VCC and connected to the ground GND, and the output terminal V_IN is connected to the analog-to-digital conversion module ports b1-b8;

[0038] The analog-to-digital conversion module 203 is powered by an AC power source VCC and is connected to a ground GND; the analog-to-digital conversion module 203 converts the voltage signal into a digital signal and is connected to the RS485 communication module 204 for communication;

[0039] The RS485 communication module 204 is powered by an AC power source VCC and is connected to the ground GND, and transmits the resistivity information to the underground ring network switch 3;

[0040] The signal transmission system B includes an underground ring network switch 3, a ground ring network switch 4, a monitoring host 5, a monitoring standby machine 6, and a Web publishing 7;

[0041] The downhole ring network switch 3 is connected to the data collector 2 in the carbon fiber composite material sensor A, and the data collector 2 converts the voltage signal into a digital signal and communicates with the downhole ring network switch 3;

[0042] The ground ring network switch 4 is connected to the underground ring network switch 3, and the signal is transmitted from the underground ring network switch 3 to the ground ring network switch 4 through the optical fiber communication network, so as to realize the data transmission between the underground and the surface;

[0043] The monitoring host 5, the monitoring standby machine 6, and the Web publishing 7 are connected to the ground ring network switch 4 for communication, thus realizing real-time online monitoring of data.

[0044] like Figure 4As shown, the present invention provides a mine filling body health monitoring method based on a carbon fiber composite material sensor, using the mine filling body health monitoring system based on a carbon fiber composite material sensor as described above, comprising the following steps:

[0045] Step 1: Fully mix carbon fiber and fly ash, gangue powder, cement and other materials to prepare carbon fiber composite filling material slurry. When preparing the carbon fiber composite filling material slurry, considering that the carbon fiber filling body is immersed in the water-containing goaf for a long time, the conductive ions inside it will be continuously precipitated under the influence of water, causing the resistivity of the filling body to change. However, this resistivity change is not caused by damage to the filling body. Therefore, the water in the goaf will have a greater interference with the health monitoring of the carbon fiber filling body;

[0046] To avoid interference, the concentration of carbon fiber in the carbon fiber composite filling material slurry can be increased. When the carbon fiber concentration increases to a certain value, the influence of conductive ions on the resistivity is much smaller than that of carbon fiber, and the influence of water on the resistivity of the carbon fiber filling body can be almost ignored. At the same time, considering the cost issue, the amount of carbon fiber is minimized. Therefore, based on the water inflow level of the goaf, different concentrations of carbon fiber composite filling material slurry are prepared, and the carbon fiber concentration is selected according to Table 1.

[0047] Table 1 Carbon fiber concentration corresponding to different goaf water inrush levels

[0048]

[0049] Step 2: The carbon fiber composite filling material slurry is transported to a predetermined position underground through a pipeline for pouring. After pouring, multiple groups of inert electrodes IN1 and inert electrodes IN2 are arranged in the monitoring area; multiple groups of inert electrodes IN1 and inert electrodes IN2 are arranged in a straight line, and the number of inert electrodes IN1 and inert electrodes IN2 is selected according to the monitoring accuracy requirements. The distance between each group of inert electrodes IN1 and inert electrodes IN2 should be as close as possible; multiple groups of inert electrodes IN1 and inert electrodes IN2 are connected to the data collector 2 through the armored cable 102, and the resistivity of the carbon fiber filling body 101 is automatically collected through the data collector 2 after the carbon fiber filling body 101 is cured for a certain age. The data collector 2 transmits the collected resistivity information to the monitoring host 5, the monitoring standby machine 6 and the Web publishing 7 (the monitoring standby machine 6 is activated when the monitoring host 5 fails);

[0050] Step 3: While pouring the carbon fiber composite filling material slurry, take part of the carbon fiber composite filling material slurry to make a carbon fiber filling body sample, and carry out physical and mechanical tests after a certain curing period, record the resistivity of the carbon fiber filling body when it is not damaged and the resistivity when it is completely damaged, and use acoustic emission technology to monitor the cumulative ringing coefficient of acoustic emission, based on which the damage coefficient of the carbon fiber filling body is calculated, and the relationship between the damage coefficient and resistivity of the carbon fiber filling body is established;

[0051] The damage factor (D) is defined as:

[0052]

[0053] Where: C t is the cumulative ringing coefficient of acoustic emission at time t, and C0 is the cumulative ringing coefficient of acoustic emission when the carbon fiber filling body sample is completely destroyed;

[0054] Step 4: The monitoring host 5 receives the resistivity information measured by the carbon fiber composite material sensor in real time, and converts the resistivity into the corresponding damage coefficient based on the carbon fiber filler damage coefficient-resistivity relationship established in step 3, and displays it in an image; based on the damage coefficient, the damage degree of the carbon fiber filler 101 is judged and it is determined whether to issue an early warning instruction. The threshold of the early warning instruction can be set at the front of the resistivity surge area of ​​the carbon fiber filler damage coefficient-resistivity relationship curve.

[0055] In order to further describe the present invention, more detailed embodiments are listed below for illustration.

[0056] like Figure 5As shown, the application of the mine filling body health monitoring system and monitoring method based on carbon fiber composite material sensor of the present invention in the health monitoring of the side support wall in the gob-side tunnel retaining technology; the side support wall 101 is casted with carbon fiber composite filling material, and after being cast to a predetermined height, the inert electrode IN1 and the inert electrode IN2 are arranged in the side support wall 101 along the direction at a certain interval, and the side support wall 101 is continued to be cast; the data collector 2 is arranged near the stop line of the working face, and the inert electrode IN1 and the inert electrode IN2 are connected to the data collector 2 with an armored cable 102; the data collector 2 converts the voltage signal into a digital signal and communicates with the underground ring network switch 3, and transmits it to the ground ring network switch 4 through the optical fiber communication network, and the ground ring network switch 4 is connected to the monitoring host 5, the monitoring standby machine 6, and the Web publishing 7 ; When damage occurs in the monitoring area of ​​the tunnel side support wall 101, the resistivity of the tunnel side support wall 101 between the inert electrode IN1 and the inert electrode IN2 will increase; the data analysis monitoring host 5 calculates the damage coefficient of the current tunnel side support wall 101 according to the monitored resistivity. When the damage coefficient is less than the critical value, it is determined that the tunnel side support wall 101 is only damaged and cracked but can still remain stable; the growth of the damage coefficient is obtained. When the damage coefficient continues to grow, it indicates that the tunnel side support wall 101 is in continuous destruction, and attention should be paid to possible accidents and reinforcement measures should be taken in advance; when the damage coefficient stops growing immediately, it indicates that the tunnel side support wall 101 has entered a relatively stable state; before the damage coefficient reaches the set threshold, a warning instruction is issued, and it is determined that the tunnel side support wall 101 has suffered major damage and is about to become unstable.

[0057] Of course, the above description is only a preferred embodiment of the present invention, and the present invention is not limited to the above embodiments. It should be noted that all equivalent substitutions and obvious deformation forms made by any technician familiar with the field under the guidance of this specification fall within the essential scope of this specification and should be protected by the present invention.

Claims

1. A mine filling health monitoring system based on carbon fiber composite material sensors, characterized in that: It includes a carbon fiber composite material sensor and a signal transmission system arranged underground; the carbon fiber composite material sensor includes carbon fiber, filling material, inert electrode IN1, inert electrode IN2, armored cable and data acquisition device; the inert electrode IN1 and inert electrode IN2 are arranged in the carbon fiber filling body; The tails of the inertial electrodes IN1 and IN2 are connected to the armored cables, and the armored cables are connected to the data collector; the data collector includes a bridge circuit, a signal amplification module, an analog-to-digital conversion module, and an RS485 communication module connected in sequence; the signal transmission system includes a downhole ring network switch, a ground ring network switch, and a monitoring host; the downhole ring network switch is connected to the data collector, and the data collector converts the voltage signal into a digital signal and communicates with the downhole ring network switch; the ground ring network switch is connected to the downhole ring network switch; the monitoring host is communicatively connected to the ground ring network switch.

2. The mine filling body health monitoring system according to claim 1, characterized in that: The circuit bridge includes a first socket, a second socket, a first resistor, a second resistor, a third resistor and an AC power supply; the inertial electrode IN1 is connected to the second socket, and the inertial electrode IN2 is connected to the first socket; the second resistor is connected in series with the first socket and the second socket to form a first branch, the first resistor is connected in series with the third resistor to form a second branch, the first branch and the second branch are connected in parallel, and the connection points of the first branch and the second branch are respectively connected to the AC power supply AC; a first connecting line is arranged on the first branch between the second resistor and the second socket, and the first connecting line is connected to the corresponding end circuit of the signal amplification module, and a second connecting line is arranged on the second branch between the first resistor and the third resistor, and the second connecting line is connected to the corresponding end circuit of the signal amplification module.

3. The mine filling body health monitoring system according to claim 2, characterized in that: The signal amplification module is powered by an AC power source VCC and is connected to a ground GND, and an output terminal V_IN is connected to ports b1 - b8 of the analog-to-digital conversion module.

4. The mine filling body health monitoring system according to claim 3, characterized in that: The analog-to-digital conversion module is powered by an AC power supply VCC and is connected to a ground GND; the analog-to-digital conversion module converts a voltage signal into a digital signal and is connected to a RS485 communication module for communication.

5. The mine filling body health monitoring system according to claim 4, characterized in that: The RS485 communication module is powered by an AC power supply VCC and is connected to a ground GND, and transmits resistivity information to an underground ring network switch.

6. The mine filling body health monitoring system according to claim 5, characterized in that: The signal transmission system also includes a monitoring standby machine and a Web publishing machine; the monitoring standby machine and the Web publishing machine are in communication connection with a ground ring network switch.

7. A mine filling body health monitoring method based on a carbon fiber composite material sensor, using a mine filling body health monitoring system according to any one of claims 1 to 6, characterized in that: The steps include: Step 1: Fully mix carbon fiber, fly ash, gangue powder and cement materials to prepare carbon fiber composite filling material slurry; Step 2: The carbon fiber composite filling material slurry is transported to a predetermined position underground through a pipeline for pouring. After pouring, multiple sets of inert electrodes IN1 and IN2 are arranged in the monitoring area; the multiple sets of inert electrodes IN1 and IN2 are connected to the data collector through armored cables; After the carbon fiber filling body is cured for a certain age, the resistivity of the carbon fiber filling body is automatically collected through the data collector, and the data collector transmits the collected resistivity information to the monitoring host through the underground ring network switch and the ground ring network switch; Step 3: While pouring the carbon fiber composite filling material slurry, take part of the carbon fiber composite filling material slurry to make a carbon fiber filling body sample, and carry out physical and mechanical tests after curing for a certain age, record the resistivity of the carbon fiber filling body when it is not damaged and the resistivity when it is completely damaged, and use acoustic emission technology to monitor the cumulative ringing coefficient of acoustic emission, based on which the damage coefficient of the carbon fiber filling body is calculated, and the relationship between the damage coefficient and resistivity of the carbon fiber filling body is established; Step 4: The monitoring host receives the resistivity information in real time, and converts the resistivity into the corresponding damage coefficient based on the carbon fiber filler damage coefficient-resistivity relationship established in step 3; The damage degree of the carbon fiber filling body is determined based on the damage coefficient.

8. The monitoring method according to claim 7, characterized in that: In step 1, the water content information of the goaf is obtained, and the carbon fiber content is determined based on the water content information of the goaf, so that the influence of conductive ions on the resistivity is much smaller than that of carbon fibers, and even the influence of water on the resistivity of the carbon fiber filling body can be almost ignored.

9. The monitoring method according to claim 8, characterized in that: In step 2, multiple groups of inert electrodes IN1 and inert electrodes IN2 are arranged in a straight line, and the number of inert electrodes IN1 and inert electrodes IN2 is selected according to the monitoring accuracy requirement.

10. The monitoring method according to claim 9, characterized in that: In step 4, the damage degree of the carbon fiber filler is judged based on the damage coefficient and whether to issue an early warning instruction is determined. The threshold of the early warning instruction is set at the front of the resistivity surge area of ​​the carbon fiber filler damage coefficient-resistivity relationship curve.

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