Performance Resistance Monitoring System and Method for Load-Environment Coupled Loading CFRP Components

Abstract

The present invention provides a performance resistance monitoring system and method for a CFRP component under coupled loading of load and environment, which relates to the technical field of carbon fiber composite materials. The system includes a stress loading and regulation component, a water circulation component, a radial resistance detection component, and a transverse resistance monitoring component. The present invention aims to realize the dynamic monitoring of the conductivity, water absorption rate, and damage process of the material by real-time monitoring of the resistance change law of the CFRP. The system includes a stress loading and regulation component, a radial resistance monitoring component, a water circulation component, and a transverse resistance monitoring component. Through long-term resistance monitoring, analysis of the correspondence between mechanical properties and resistance, establishment of empirical model formulas, and estimation of the degree of mechanical property attenuation, the present invention provides an efficient and non-destructive evaluation method for predicting the service life of CFRP, guiding maintenance and replacement strategies. The present invention realizes the real-time dynamic monitoring of the conductivity, water absorption rate, and damage process of CFRP under the coupled action of multiple factors of force, salt, heat, and humidity.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon fiber composite materials, and particularly to a performance resistance monitoring system and method for a CFRP component under coupled loading of load and environment. Background Art

[0002] Due to its advantages such as high specific strength, high specific modulus, low density, corrosion resistance, and strong designability, CFRP is used in fields such as aviation, aerospace, military, communication, sports, and construction. Under various working conditions of civil engineering such as in the ocean, on the ground surface, and in deep earth, pultruded CFRP rods / plates and other structures are common product forms of composite materials. Under certain working stress conditions, CFRP rods / plates are usually accompanied by certain influences such as humidity, salt, and temperature, and thus their performance deteriorates. At present, for the performance monitoring of pultruded CFRP rods / plates under the coupled action of multiple factors, especially the non-destructive on-line dynamic monitoring of water absorption rate and damage process, there is still a lack of effective monitoring means and evaluation models. Summary of the Invention

[0003] In order to solve a technical problem existing in the prior art, an embodiment of the present invention provides a performance resistance monitoring system and method for a CFRP component under coupled loading of load and environment. By real-time monitoring the resistance change law of the composite material, the dynamic monitoring of the conductivity, water absorption rate, and damage process of the carbon fiber composite material is realized, and an empirical model is established to evaluate the attenuation laws of the conductivity, water absorption rate, and mechanical properties of the material under the long-term coupled action of multiple factors. The technical solution is as follows:

[0004] A performance resistance monitoring system for a CFRP component under coupled loading of load and environment, comprising:

[0005] A stress loading and regulating component, both ends of the CFRP component are loaded on the stress loading and regulating component, and the stress loading and regulating component can perform constant stress or variable stress loading on the CFRP component. Among them, the CFRP component is a CFRP plate or a CFRP rod, and a water circulation component, a radial resistance detection component, and a transverse resistance monitoring component are installed on the stress loading and regulating component;

[0006] A water circulation component, the CFRP component passes through the water circulation component, and the water circulation component is used to simulate the use environment of the CFRP component. Among them, the water circulation component supports adjusting the salt concentration, temperature, and humidity in the use environment of the CFRP component according to the actual environment;

[0007] A radial resistance detection component, used to detect the change in the resistance value of the CFRP component in the first direction, and the first direction is parallel to the fiber direction of the CFRP component;

[0008] The transverse resistance detection component is used to detect the change of the resistance value of the CFRP member in a second direction, and the second direction is perpendicular to the fiber direction of the CFRP member.

[0009] Optionally, the stress loading regulation component includes:

[0010] A mold fixing base, wherein the mold fixing base is arranged horizontally;

[0011] A first mold fixing bracket and a second mold fixing bracket, wherein the first mold fixing bracket and the second mold fixing bracket are symmetrically mounted at two ends of the upper surface of the first mold fixing base;

[0012] A mold driving assembly, the mold driving assembly is installed on the mold fixing base and is arranged on the mold second fixing bracket side;

[0013] An anchor, one end of which is mounted on the first fixing bracket, the other end of which is mounted on the first-mold driving assembly, and both ends of the CFRP member are mounted in both ends of the anchor;

[0014] A force sensor, the force sensor being mounted on the first fixed support side of the first mold and on the anchor;

[0015] A first-mode controller, the first-mode controller is respectively connected to the force sensor and the first-mode drive assembly by telecommunication;

[0016] Wherein, the one-mold driving assembly supports and drives the anchor on the same end side to move horizontally.

[0017] Optionally, the first-mode driving component includes:

[0018] A servo motor support, the servo motor support being mounted on the surface of the first mold fixed base;

[0019] A servo motor, wherein the servo motor is mounted on the servo motor support;

[0020] A first gear and a second gear, wherein upper and lower ends of the second gear are respectively meshed with the first gear, and the second gear is connected to the servo motor through a coupling;

[0021] Screw rods, two of the screw rods are arranged in parallel, and one end of the two screw rods is respectively installed at the center of the two first gears;

[0022] A support plate, wherein two threaded holes are arranged on the support plate, and the two threaded holes are respectively adapted to the two screw rods, and an end of the anchor away from the first fixed bracket of the first mold is arranged on the end side of the support plate away from the first fixed bracket of the first mold, and the CFRP part passes through the support plate and is installed on the end of the anchor away from the first fixed bracket of the first mold;

[0023] When the servo motor drives the second gear to rotate, the second gear drives two first gears to rotate, and the two first gears respectively drive the corresponding screws to rotate. The support plate moves along the horizontal direction of the screws and drives the two ends of the anchor to approach or move away from each other accordingly.

[0024] Optionally, the water circulation assembly includes:

[0025] A target water pipe, which is arranged above the first die fixing base. One end of the target water pipe is blocked by a first silica gel plug, and the other end of the target water pipe is blocked by a third silica gel plug. The CFRP part sequentially passes through the first silica gel plug, the target water pipe and the third silica gel plug, and the target water pipe is installed in a target water pipe heat preservation sleeve;

[0026] An electric heating pipe, on the outer wall of which an electric heating tape is installed. On the outer wall of the electric heating tape, an electric heating tape heat preservation sleeve is arranged. The electric heating tape heat preservation sleeve is installed on a first fixing support and a second fixing support of the electric heating pipe, and the first fixing support and the second fixing support of the electric heating pipe are installed on the upper surface of the first die fixing base;

[0027] A three-mode controller, which is installed on a three-mode controller support. The three-mode controller support is installed on the upper surface of the first die fixing base. The three-mode controller is electrically connected to the electric heating tape and a temperature sensor, and the temperature sensor is installed in the target water pipe;

[0028] A first hose, a second hose and a third hose. One end of the first hose is connected to one end of the electric heating pipe, and the other end of the first hose is connected to a circulating water pump. The other end of the circulating water pump is connected to one end of the second hose. The other end of the second hose is connected to the end side wall of one end of the target water pipe through a first three-way joint. One end of the third hose is connected to the other end of the electric heating pipe, and the other end of the third hose is connected to the end side wall of the other end of the target water pipe through a third three-way joint;

[0029] Wherein, a first hose heat preservation sleeve is arranged on the first hose, a second hose heat preservation sleeve is arranged on the second hose, a third hose heat preservation sleeve is arranged on the third hose, and the circulating water pump is electrically connected to the three-mode controller;

[0030] A water level monitoring pipe, which is vertically installed above the target water pipe and is connected to the target water pipe through a second three-way joint. A second silica gel plug is arranged at the end of the water level monitoring pipe;

[0031] A water discharge valve and a water tank. A fourth three-way joint is arranged on the electric heating tube and on the same side as the third hose. The fourth three-way joint connects the electric heating tube and the third hose. A water discharge valve is arranged at the other end of the fourth three-way joint, and a water tank is arranged below the water discharge valve.

[0032] Optionally, the transverse resistance detection assembly:

[0033] A four-mode resistance recorder, which is installed on the four-mode resistance recorder support, and the four-mode resistance recorder support is installed on the first-mode fixed base;

[0034] A four-mode first wire and a four-mode second wire. One ends of the four-mode first wire and the four-mode second wire are respectively connected to the four-mode resistance recorder. The other end of the four-mode first wire is provided with m parallel branches, and each branch of the four-mode first wire is connected to a four-mode wet transverse resistance electrode, and the four-mode wet transverse resistance electrode is arranged on the CFRP part. The other end of the four-mode second wire is provided with m parallel branches, and each branch of the four-mode second wire is connected to a four-mode dry transverse resistance electrode, and the four-mode dry transverse resistance electrode is arranged on the CFRP part coated with a four-mode hydrophobic coating;

[0035] A four-mode silicone rubber capillary sleeve, which is installed on the four-mode first wire and the four-mode second wire.

[0036] Optionally, the radial resistance detection assembly includes:

[0037] A two-mode resistance recorder, which is installed on the two-mode resistance recorder support, and the two-mode resistance recorder support is installed on the first-mode fixed base;

[0038] A two-mode first wire, a two-mode second wire and a two-mode third wire. One end of the two-mode first wire is connected to the two-mode first electrode, the other end of the two-mode first wire is connected to the two-mode resistance recorder, one end of the two-mode second wire is connected to the two-mode second electrode, the other end of the two-mode second wire is connected to the two-mode resistance recorder, one end of the two-mode third wire is connected to the two-mode third electrode, and the other end of the two-mode third wire is connected to the two-mode resistance recorder.

[0039] Wherein, the two-mode first electrode, the two-mode second electrode and the two-mode third electrode are evenly spaced and installed on the CFRP part and inside the target water pipe, and two-mode silicone rubber capillary sleeves are arranged on the wire bodies of the two-mode first wire, the two-mode second wire and the two-mode third wire;

[0040] Wherein, a CFRP hydrophobic coating is arranged on the CFRP part between the two-mode first electrode and the two-mode second electrode;

[0041] Among them, the second-mode first electrode, the second-mode second electrode, and the second-mode third electrode have the same structure.

[0042] Optionally, the second-mode first electrode includes: a metal electrode, a highly conductive adhesive, and an electrode hydrophobic coating;

[0043] The metal electrode is installed on the CFRP part through the highly conductive adhesive;

[0044] The surface of the metal electrode is coated with an electrode hydrophobic coating.

[0045] Optionally, the electric heating tape is a glass fiber tracing tape, a carbon fiber heating tape, or a silicone rubber tracing tape.

[0046] A performance resistance monitoring method for a load environment coupled loading CFRP part includes:

[0047] Install the CFRP part on the anchor, where conductive sheets and coatings are pre-arranged on the CFRP part according to preset requirements;

[0048] After adding a solution into the target water pipe from the water level monitoring pipe until reaching the target height according to preset requirements, adjust the temperature in the target water pipe through the water circulation component;

[0049] Adjust the stress applied on the CFRP part based on the stress loading control component;

[0050] At every preset time interval, collect the resistance values on the second-mode resistance recorder and the fourth-mode resistance recorder and upload the collected values to the upper computer;

[0051] Among them, regularly detect the water level height in the water level monitoring pipe. If it is lower than the preset water level height, supplement the solution;

[0052] When the number of times of resistance value detection reaches the preset requirements, the electric heating pipe stops working, drain the solution through the drain valve, and unload the stress applied on the CFRP part through the stress loading control component;

[0053] Based on the data of the second-mode resistance recorder, the data of the fourth-mode resistance recorder, and the parameters of the solution, obtain an empirical model between the resistance, the water absorption rate of the CFRP part, and the mechanical properties of the CFRP part.

[0054] Optionally, the empirical model between the resistance, the water absorption rate of the CFRP part, and the mechanical properties of the CFRP part includes:

[0055] The influence of the water absorption rate on the conductivity of the CFRP part is formula (1):

[0056] ΔG water= G2 - G1 = L2 / (A·ρ2) - L1 / (A·ρ1); (1)

[0057] Among them, ΔG wate is the change in the conductivity of CFRP caused by moisture absorption, G1 is the conductivity of the non-moisture-absorbing section, G2 is the conductivity of the moisture-absorbing section, A is the cross-sectional area of CFRP, ρ1 is the resistivity of the non-moisture-absorbing section, ρ2 is the resistivity of the moisture-absorbing section, L1 is the length of the non-moisture-absorbing section, and L2 is the length of the moisture-absorbing section;

[0058] The change in the conductivity of the non-moisture-absorbing section composite material under the coupled action of long-term load and environment is given by Equation (2):

[0059] ΔG1 t = G1 t - G1 0 = L1 t / (A·ρ1 t ) - L1 0 / (A·ρ1 0 ); (2)

[0060] Among them, ΔG1 t is the change in the water absorption rate of the non-moisture-absorbing section CFRP part under the coupled action of long-term load and environment, G1 t is the conductivity of the non-moisture-absorbing section CFRP part at the service time t under the coupled action of long-term load and environment, G1 0 is the conductivity of the non-moisture-absorbing section CFRP part at the initial coupled loading of load and environment, L1 t is the length of the non-moisture-absorbing section CFRP part at the service time t under the coupled action of long-term load and environment, ρ1 t is the resistance of the non-moisture-absorbing section CFRP part at the service time t under the coupled action of long-term load and environment, L1 0 is the length of the non-moisture-absorbing section CFRP part at the initial coupled loading of load and environment, ρ1 0 is the resistance of the non-moisture-absorbing section CFRP part at the initial coupled loading of load and environment;

[0061] The prediction formula for the change in the conductivity of the moisture-absorbing section composite material under the coupled action of long-term load and environment is Equation (3):

[0062] ΔG2 t = G2 t - G2 0 = L2 t / (A·ρ2 t ) - L2 0 / (A·ρ2 0 ); (3)

[0063] Among them, ΔG2 tThe change in water absorption rate of the CFRP component in the moisture absorption section under the long-term combined action of load and environment, G2 t The conductivity of the CFRP component in the moisture absorption section at the service time t under the long-term combined action of load and environment, G2 0 The conductivity of the CFRP component in the moisture absorption section when the combined loading of load and environment is initially carried out, L2 t The length of the CFRP component in the moisture absorption section at the service time t under the long-term combined action of load and environment, ρ2 t The resistance of the CFRP component in the moisture absorption section at the service time t under the long-term combined action of load and environment, L2 0 The length of the CFRP component in the moisture absorption section when the combined loading of load and environment is initially carried out, ρ2 0 The resistance of the CFRP component in the moisture absorption section when the combined loading of load and environment is initially carried out.

[0064] The beneficial effects brought by the technical solution provided by the embodiment of the present invention at least include:

[0065] 1. Realize the real-time dynamic monitoring of the conductivity, water absorption rate and damage process of CFRP under the combined action of multiple factors of force, salt, heat and humidity.

[0066] 2. Establish an empirical model to provide a scientific basis for evaluating the water absorption rate and mechanical property attenuation of CFRP under the long-term combined action of multiple factors.

[0067] 3. Provide an efficient and non-destructive evaluation method for the long-term performance monitoring of CFRP.

[0068] 4. Improve the accuracy of predicting the service life of CFRP and provide guidance for the maintenance and replacement of materials. This has important practical significance for predicting the service life of materials and guiding maintenance and replacement strategies.

[0069] 5. The water circulation component adopted by the present invention consumes less solution mass, is easy to replace and adjust, and has good experimental convenience. Brief Description of the Drawings

[0070] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0071] Figure 1 It is the overall structural schematic diagram of the system provided by the embodiment of the present invention;

[0072] Figure 2 It is the schematic diagram of the stress loading and regulating component (abbreviation: one mold) provided by the embodiment of the present invention;

[0073] Figure 3 Among them, (a) is a schematic diagram of the radial resistance monitoring component (abbreviation: two-mode) provided by the embodiment of the present invention, Figure 3 and (b) is a cross-sectional view of the electrode position of the non-hygroscopic section of the CFRP radial resistance provided by the embodiment of the present invention, Figure 3 and (c) is a cross-sectional view of the composite material test section of the non-hygroscopic section of the CFRP radial resistance provided by the embodiment of the present invention;

[0074] Figure 4 is a schematic diagram of the water circulation component (abbreviation: three-mode) provided by the embodiment of the present invention;

[0075] Figure 5 Among them, (a) is a schematic diagram of the transverse resistance monitoring component (abbreviation: four-mode) provided by the embodiment of the present invention, Figure 5 and (b) is a side view of the transverse resistance electrode provided by the embodiment of the present invention, Figure 5 and (c) is a side view of the transverse resistance electrode perpendicular to the fiber cutting surface provided by the embodiment of the present invention, Figure 5 and (d) is a schematic diagram of the transverse resistance detection principle provided by the embodiment of the present invention.

[0076] Reference numerals:

[0077] 1-1, fixed base of the first mode; 1-2, first fixing bracket of the first mode; 1-3, second fixing bracket of the first mode; 1-41, servo motor support; 1-42, servo motor; 1-43, first gear; 1-44, second gear; 1-45, screw; 1-46, support plate; 1-5, anchor; 1-6, force sensor; 1-7, controller of the first mode;

[0078] 2-1, resistance recorder of the second mode; 2-2, first wire of the second mode; 2-3, second wire of the second mode; 2-4, third wire of the second mode; 2-5, first electrode of the second mode; 2-51, metal electrode; 2-52, highly conductive adhesive; 2-53, electrode hydrophobic coating; 2-6, second electrode of the second mode; 2-7, third electrode of the second mode; 2-8, CFRP hydrophobic coating;

[0079] 3-1, target water pipe; 3-2, electric heating pipe; 3-21, electric heating tape; 3-3, controller of the third mode; 3-4, first hose; 3-5, second hose; 3-6, third hose; 3-7, water level monitoring pipe; 3-8, water tank; 3-9, circulation water pump; 3-10, drain valve;

[0080] 4-1, resistance recorder of the fourth mode; 4-2, first wire of the fourth mode; 4-3, second wire of the fourth mode; 4-4, wet transverse resistance electrode of the fourth mode; 4-5, dry transverse resistance electrode of the fourth mode; 4-6, CFRP hydrophobic coating; 5, CFRP component. Detailed implementation manners

[0081] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0082] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings as understood by those of ordinary skill in the art to which the present invention pertains. The terms "first", "second" and similar words used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, the words such as "a", "an" or "the" do not denote a quantity limitation, but mean that there is at least one. The words such as "comprising" or "including" mean that the elements or items appearing before the word cover the elements or items listed after the word and their equivalents, without excluding other elements or items. The words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0083] It should be noted that the terms "upper", "lower", "left", "right", "front", "rear", etc. used in the present invention are only used to represent relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0084] As Figures 1 to 5As shown in the figure, a performance resistance monitoring system for a load environment coupled with a CFRP component includes: a stress loading and regulating component, a water circulation component, a radial resistance detection component, and a transverse resistance monitoring component. Both ends of the CFRP component 5 are mounted on the stress loading and regulating component, and the stress loading and regulating component can apply constant stress or variable stress to the CFRP component 5. Among them, the CFRP component 5 is a CFRP plate or a CFRP rod, and the water circulation component, the radial resistance detection component, and the transverse resistance monitoring component are installed on the stress loading and regulating component; the CFRP component 5 passes through the water circulation component, and the water circulation component is used to simulate the use environment of the CFRP component 5. Among them, the water circulation component supports adjusting the salt concentration, temperature, and humidity in the use environment of the CFRP component 5 according to the actual environment; the radial resistance detection component is used to detect the change in the resistance value of the CFRP component 5 in the first direction, and the first direction is parallel to the fiber direction of the CFRP component 5; the transverse resistance monitoring component is used to detect the change in the resistance value of the CFRP component 5 in the second direction, and the second direction is perpendicular to the fiber direction of the CFRP component 5.

[0085] Among them, the CFRP component is a composite material, such as carbon fiber composite material.

[0086] In a specific implementation manner, the stress loading and regulating component includes: a first fixed base 1-1, a first fixed bracket 1-2, a second fixed bracket 1-3, a driving component, an anchor 1-5, a force sensor 1-6, and a first controller 1-7; the first fixed base 1-1 is horizontally arranged; the first fixed bracket 1-2 and the second fixed bracket 1-3 are symmetrically installed at both ends of the upper surface of the first fixed base 1-1; the driving component is installed on the first fixed base 1-1 and is arranged on the side of the second fixed bracket 1-3; one end of the anchor 1-5 is installed on the first fixed bracket, the other end of the anchor 1-5 is installed on the driving component, and both ends of the CFRP component 5 are installed inside both ends of the anchor 1-5; the force sensor 1-6 is installed on the side of the first fixed bracket 1-2 and is installed on the anchor 1-5; the first controller 1-7 is respectively connected to the force sensor 1-6 and the driving component by telecommunications; the driving component supports driving the anchor 1-5 on the same end side to move in the horizontal direction.

[0087] In a specific embodiment, the first die driving assembly includes: a servo motor support 1-41, a servo motor 1-42, a first gear 1-43, a second gear 1-44, a screw 1-45, and a support plate 1-46. The servo motor support 1-41 is installed on the surface of the first die fixed base 1-1; the servo motor 1-42 is installed on the servo motor support 1-41; the upper and lower ends of the second gear 1-44 are respectively engaged with the first gear 1-43, and the second gear 1-44 is connected to the servo motor 1-42 through a coupling; the two screws 1-45 are arranged in parallel, and one ends of the two screws 1-45 are respectively installed at the centers of the two first gears 1-43; two threaded holes are provided on the support plate 1-46, and the two threaded holes are respectively adapted to the two screws 1-45. One end of the anchor 1-5 away from the first die first fixed bracket 1-2 is arranged on the side of the support plate 1-46 away from the first die first fixed bracket 1-2, and the CFRP member 5 is installed through the support plate 1-46 at one end of the anchor 1-5 away from the first die first fixed bracket 1-2; when the servo motor 1-42 drives the second gear 1-44 to rotate, the second gear 1-44 drives the two first gears 1-43 to rotate, and the two first gears 1-43 respectively drive the corresponding screws 1-45 to rotate, and the support plate 1-46 moves along the horizontal direction of the screw 1-45 while driving the two ends of the anchor 1-5 to approach or move away from each other relatively.

[0088] In a specific embodiment, the water circulation assembly includes:

[0089] A target water pipe 3-1, which is arranged above the first die fixed base 1-1. One end of the target water pipe 3-1 is blocked by a first silicone plug, and the other end of the target water pipe 3-1 is blocked by a third silicone plug. The CFRP member 5 sequentially passes through the first silicone plug, the target water pipe 3-1, and the third silicone plug, and the target water pipe 3-1 is installed in a target water pipe 3-1 heat preservation sleeve;

[0090] An electric heating pipe 3-2, on the outer wall of which an electric heating tape 3-21 is installed. An electric heating tape 3-21 heat preservation sleeve is arranged on the outer wall of the electric heating tape 3-21, and the electric heating tape 3-21 heat preservation sleeve is installed on a first fixed support of the electric heating pipe 3-2 and a second fixed support of the electric heating pipe 3-2. The first fixed support of the electric heating pipe 3-2 and the second fixed support of the electric heating pipe 3-2 are installed on the upper surface of the first die fixed base 1-1;

[0091] Three - mode controller 3 - 3, the three - mode controller 3 - 3 is installed on the three - mode controller 3 - 3 support, the three - mode controller 3 - 3 support is installed on the upper surface of the first - mode fixed base 1 - 1, the three - mode controller 3 - 3 is electrically connected to the electric heating tape 3 - 21 and the temperature sensor, and the temperature sensor is installed in the target water pipe 3 - 1; the temperature sensor supports detecting the temperature in the target water pipe. When the temperature in the target water pipe detected by the temperature sensor is higher than the required temperature, the heating tape stops heating until the temperature in the target water pipe drops to the required temperature range, then the heating tape heats and controls the temperature of the circulating water within the required temperature range. If the temperature in the target water pipe is lower than the required temperature, the heating tape heats.

[0092] The first hose 3 - 4, the second hose 3 - 5 and the third hose 3 - 6. One end of the first hose 3 - 4 is connected to one end of the electric heating pipe 3 - 2, the other end of the first hose 3 - 4 is connected to the circulating water pump 3 - 9, the other end of the circulating water pump 3 - 9 is connected to one end of the second hose 3 - 5, the other end of the second hose 3 - 5 is connected to the end side wall of one end of the target water pipe 3 - 1 through a first three - way joint, one end of the third hose 3 - 6 is connected to the other end of the electric heating pipe 3 - 2, and the other end of the third hose 3 - 6 is connected to the end side wall of the other end of the target water pipe 3 - 1 through a third three - way joint;

[0093] Among them, a first hose 3 - 4 insulation sleeve is arranged on the first hose 3 - 4, a second hose 3 - 5 insulation sleeve is arranged on the second hose 3 - 5, a third hose 3 - 6 insulation sleeve is arranged on the third hose 3 - 6, and the circulating water pump 3 - 9 is electrically connected to the three - mode controller 3 - 3;

[0094] The water level monitoring pipe 3 - 7 is vertically installed above the target water pipe 3 - 1 and is connected to the target water pipe 3 - 1 through a second three - way joint, and a second silicone plug is arranged at the end of the water level monitoring pipe;

[0095] The drain valve 3 - 10 and the water tank 3 - 8. A fourth three - way joint is arranged on the electric heating pipe 3 - 2 and on the same side as the third hose 3 - 6. The fourth three - way joint connects the electric heating pipe 3 - 2 and the third hose 3 - 6, and a drain valve 3 - 10 is arranged at the other end of the fourth three - way joint, and a water tank 3 - 8 is arranged below the drain valve 3 - 10;

[0096] A specific implementation method, the transverse resistance detection component:

[0097] Four - mode resistance recorder 4 - 1, the four - mode resistance recorder 4 - 1 is installed on the four - mode resistance recorder 4 - 1 support, and the four - mode resistance recorder 4 - 1 support is installed on the first - mode fixed base 1 - 1;

[0098] The four-mode first wire 4-2 and the four-mode second wire 4-3, one ends of the four-mode first wire 4-2 and the four-mode second wire 4-3 are respectively connected to the four-mode resistance recorder 4-1, the other end of the four-mode first wire 4-2 is provided with m parallel branches, each branch of the four-mode first wire 4-2 is connected to a four-mode wet transverse resistance electrode 4-4, the four-mode wet transverse resistance electrode 4-4 is arranged on the CFRP member 5, the other end of the four-mode second wire 4-3 is provided with m parallel branches, each branch of the four-mode second wire 4-3 is connected to a four-mode dry transverse resistance electrode 4-5, the four-mode dry transverse resistance electrode 4-5 is arranged on the CFRP member 5 coated with the four-mode hydrophobic coating 4-6;

[0099] The four-mode silicone rubber capillary sleeve is installed on the four-mode first wire 4-2 and the four-mode second wire 4-3.

[0100] In a specific embodiment, the radial resistance detection assembly includes:

[0101] The two-mode resistance recorder 2-1 is installed on the two-mode resistance recorder 2-1 support, and the two-mode resistance recorder 2-1 support is installed on the one-mode fixed base 1-1;

[0102] The two-mode first wire 2-2, the two-mode second wire 2-3 and the two-mode third wire 2-4, one end of the two-mode first wire 2-2 is connected to the two-mode first electrode 2-5, the other end of the two-mode first wire 2-2 is connected to the two-mode resistance recorder 2-1, one end of the two-mode second wire 2-3 is connected to the two-mode second electrode 2-6, the other end of the two-mode second wire 2-3 is connected to the two-mode resistance recorder 2-1, one end of the two-mode third wire 2-4 is connected to the two-mode third electrode 2-7, and the other end of the two-mode third wire 2-4 is connected to the two-mode resistance recorder 2-1,

[0103] Wherein, the two-mode first electrode 2-5, the two-mode second electrode 2-6 and the two-mode third electrode 2-7 are evenly spaced and installed on the CFRP member 5 and inside the target water pipe 3-1, and two-mode silicone rubber capillary sleeves are arranged on the wire bodies of the two-mode first wire 2-2, the two-mode second wire 2-3 and the two-mode third wire 2-4;

[0104] Wherein, a CFRP hydrophobic coating 2-8 is arranged on the CFRP member 5 between the two-mode first electrode 2-5 and the two-mode second electrode 2-6;

[0105] Wherein, the two-mode first electrode 2-5, the two-mode second electrode 2-6 and the two-mode third electrode 2-7 have the same structure.

[0106] In a specific practical manner, the second-mode first electrode 2-5 includes: a metal electrode 2-51, a highly conductive adhesive 2-52, and an electrode hydrophobic coating 2-53; the metal electrode 2-51 is mounted on the CFRP member 5 through the highly conductive adhesive 2-52; an electrode hydrophobic coating 2-53 is coated on the surface of the metal electrode 2-51. The electric heating tape 3-21 is a glass fiber heating tape, a carbon fiber heating tape, or a silicone rubber heating tape.

[0107] The force sensor 1-6 is a spoke-type sensor, the maximum range of the sensor is 5t, and the load applied to the composite material (CFRP member 5) is 25KN. The first fixing bracket 1-2 of the first mold selects an I-beam, the fixed base 1-1 of the first mold is a steel plate with a thickness of 50mm, the high-strength screw 1-45 selects a 12.9-grade semi-threaded high-strength screw 1-45, the gasket uses a die steel ring gasket, the gears and couplings are both made of stainless steel or low-carbon steel, and the servo motor 1-42 uses a high-torque AC gear reduction motor. The target water pipe 3-1 and the heating pipe can select one of the PTFE pipe, titanium pipe, quartz pipe, and stainless steel pipe with better corrosion resistance and temperature resistance according to the solution type. The above-mentioned relevant hoses can select plastic pipes with better elasticity and deformability such as silicone hoses. The electric heating tape 3-21 selects a glass fiber heating tape. The solution is a 10% sodium chloride aqueous solution.

[0108] The specific principle of the present invention includes:

[0109] The moisture content in the composite material has a direct impact on the resistivity or conductivity of the composite material. Therefore, under the multi-factor coupling action of force, salt, heat, and humidity on the CFRP sample, the length-direction resistance R 纵 and the transverse resistances R such as width and thickness 横 are monitored for a long time. The system can obtain the change process of the resistance over time t. During this process, the water absorption rate of the composite material gradually increases, and salt ions gradually penetrate into the interior of the composite material. The increase in the moisture content and salt ion concentration in the composite material can increase the conductivity or decrease the resistivity of the composite material, and there is a significant positive correlation between the two. Therefore, the long-term dynamic non-destructive monitoring of the water absorption rate of the composite material can be realized through this principle.

[0110] In addition, since the composite material is tested under the multi-factor coupling action of force, salt, heat, and humidity, especially there is a certain load level of prestress inside the composite material. Under the long-term coupling action of the load environment, the small defects generated inside the composite material are more likely to expand compared with the case without applying force. The expansion of the internal defects of the composite material will cause a sudden change in the resistivity or conductivity of the material itself. Therefore, the real-time non-destructive monitoring of the internal damage of the composite material can be realized by long-term resistance monitoring of the CFRP sample. Further, the mechanical properties M of the CFRP under different experimental conditions can be analyzed by comparison CFRP, such as the corresponding relationships between the tensile strength, tensile modulus, interlaminar shear strength, flexural strength, flexural modulus, etc. and the resistance or conductivity changes, to reveal the internal connection between the attenuation of material properties and the resistance changes. Long-term monitoring of R 纵 and R 横 variation rules, and analyze the corresponding relationships between the resistance changes and the water absorption rate and mechanical property test results, and predict the attenuation degree of the water absorption rate and mechanical properties of CFRP by measuring the resistance.

[0111] In this R x resistance system, since carbon fiber is composed of microcrystals with turbostratic graphite stacking, the water absorption rate is extremely low and the resistance can be considered constant. However, there is a certain proportion of resin in the transition layer between adjacent two carbon fibers. Under the coupled action of the long-term load environment, the water content and salt ions in the transition layer of the composite material increase, which will lead to a decrease in the resistance in the transition layer. Therefore, by long-term monitoring of the variation rule of the transverse resistance, the variation rules of the water content and salt ion concentration in the composite material can be indirectly calculated.

[0112] Furthermore, by comparing and analyzing the mutation conditions of the resistance or conductivity of the composite material longitudinally or transversely in the moisture absorption section, the variation rule of the damage in the composite material can be monitored in real time. By testing and analyzing the mechanical properties of the composite material under different experimental conditions, such as tensile strength, tensile modulus, interlaminar shear strength, flexural strength, flexural modulus, etc., analyze the corresponding relationships between the attenuation rules of the mechanical properties of the composite material after the aging experiment under the coupled action of the long-term load environment and the resistance or conductivity changes, reveal the internal connection between the attenuation of material properties and the resistance changes, and predict the attenuation degree of the mechanical properties of CFRP by measuring the resistance.

[0113] The specific operation steps are as follows:

[0114] A method for monitoring the performance resistance of a CFRP component under the coupled loading of a load environment, including:

[0115] S1. Install the CFRP component on the anchor, where conductive sheets and coatings are pre-arranged on the CFRP component according to preset requirements. Specifically, it includes:

[0116] Installation and anchoring: Cut the CFRP into a certain length, paste conductive sheets or coatings at specific positions on the surface of the CFRP, and spray a waterproof coating or wrap a water-proof film on specific parts. The CFRP rod passes through the force sensor, the water circulation component, etc. in turn, and mechanically clamp and anchor or adhesively anchor both ends of the CFRP with the anchor.

[0117] S2. After adding the solution into the target water pipe from the water level monitoring pipe until reaching the target height according to the preset requirements, adjust the temperature in the target water pipe through the water circulation component. Specifically, it includes:

[0118] Injecting solution: Prepare the types of solutions required for the aging test, and inject the solution from the water injection port at the upper end of the water level monitoring tube until it reaches a certain height in the water level monitoring tube. Set the temperature rising and falling program of the temperature controller and run it.

[0119] The working method of the water circulation component is as follows: Inject a low-temperature solution (1 degree - 10 degrees), a solution lower than the target temperature, into the water level monitoring tube of the system. Then, after entering the water circulation system of the system, the temperature sensor and the heating tube heat the solution until it reaches the target temperature (it can be judged whether the target temperature is reached by setting temperature sensors in the heating tube and the target water pipe respectively, and the temperature sensors monitor in real time). When heated to the target temperature, the temperature may continue to rise. Generally, there is also a temperature fluctuation range in the simulated internal environment temperature. As long as the target temperature is within this range, the aging process of the CFRP component under this temperature condition can be simulated.

[0120] S3. Based on the stress loading and regulating component, adjust the stress on the CFRP component, set the stress level and other parameters of the stress controller, and apply stress to the CFRP according to the set program. The relevant program control method can be manipulated by those skilled in the art according to the prior art, and will not be elaborated here.

[0121] S4. Every preset time period, collect the resistance values on the two-mode resistance recorder and the four-mode resistance recorder once and upload the collected values to the upper computer; regularly detect the water level height in the water level monitoring tube. If it is lower than the preset water level height, replenish the solution.

[0122] The specific operation is as follows: Open the relevant resistance recorder to collect the longitudinal and transverse resistance values of the CFRP. The recorder automatically stores the resistance values at regular intervals. At regular intervals, observe the water level height in the water level monitoring tube. If the water level drops, replenish the solution.

[0123] S5. When the number of times of resistance value detection reaches the preset requirement, the electric heating tube stops working, drain the solution through the drain valve, and unload the stress applied to the CFRP component through the stress loading and regulating component.

[0124] After the load environment coupling aging experiment is completed, turn off the heating program of the controller, open the drain valve 5-6, empty the solution in the water circulation component, unload the prestress, take out the CFRP, cut off the part soaked in the solution, and conduct mechanical and physical and chemical property tests on the composite material.

[0125] S6. Based on the data of the two-mode resistance recorder, the data of the four-mode resistance recorder and the parameters of the solution, obtain an empirical model between the resistance, the water absorption rate of the CFRP component and the mechanical properties of the CFRP component. The specific operation is as follows:

[0126] Data analysis: By comparing and analyzing the corresponding relationship between the mechanical properties and resistance of CFRP under the salt-thermal-humidity experimental conditions of different forces, an empirical model formula between resistance, water absorption rate and mechanical properties of CFRP is established, correlating the resistance change with the water absorption rate and the attenuation degree of mechanical properties of the material, providing a quantitative tool for performance evaluation.

[0127] Prediction of long-term service life of CFRP: Using the established empirical model formula, the prediction of the water absorption rate and the attenuation degree of mechanical properties of CFRP is realized by measuring the resistance.

[0128] As Figure 3 shown, for CFRP, two sections of CFRP with similar or the same length are selected in the length direction. The length of the left part is L1, and the left part is isolated from water by a hydrophobic coating, which is a non-moisture-absorbing section; the length of the right part is L2, and there is no hydrophobic coating on the right part, and water molecules and salt ions are in direct contact with the composite material, which is a moisture-absorbing section. The resistivity of the left part, that is, the non-moisture-absorbing section, is ρ1, and the resistivity of the right part, that is, the moisture-absorbing section, is ρ2. Except for the different moisture absorption conditions, other conditions of the two sections of materials are kept the same, aiming to test the influence of moisture absorption on the resistivity or conductivity of the composite material. The conductivity of the non-moisture-absorbing section is G1 = A / (L1·ρ1), and the conductivity of the moisture-absorbing section is G2 = A / (L2·ρ2).

[0129] Among them, the influence of the water absorption rate on the conductivity of CFRP parts is formula (1):

[0130] ΔG water = G2 - G1 = L2 / (A·ρ2) - L1 / (A·ρ1); (1)

[0131] Among them, ΔG wate is the change in the conductivity of CFRP caused by moisture absorption, G1 is the conductivity of the non-moisture-absorbing section, G2 is the conductivity of the moisture-absorbing section, A is the cross-sectional area of CFRP, ρ1 is the resistivity of the non-moisture-absorbing section, ρ2 is the resistivity of the moisture-absorbing section, L1 is the length of the non-moisture-absorbing section, and L2 is the length of the moisture-absorbing section;

[0132] The change in the conductivity of the composite material in the non-moisture-absorbing section under the coupled action of long-term load environment is formula (2):

[0133] ΔG1 t = G1 t - G1 0 = L1 t / (A·ρ1 t ) - L1 0 / (A·ρ1 0 ); (2)

[0134] Among them, ΔG1 t is the change in the water absorption rate of the CFRP parts in the non-moisture-absorbing section under the coupled action of long-term load environment, G1t The electrical conductivity of the non - moisture - absorbing CFRP component under the long - term load - environment coupling effect at service time t is G1 0 The electrical conductivity of the non - moisture - absorbing CFRP component when initially subjected to the load - environment coupling loading is L1 t The length of the non - moisture - absorbing CFRP component under the long - term load - environment coupling effect at service time t is ρ1 t The resistance of the non - moisture - absorbing CFRP component under the long - term load - environment coupling effect at service time t is L1 0 The length of the non - moisture - absorbing CFRP component when initially subjected to the load - environment coupling loading is ρ1 0 The resistance of the non - moisture - absorbing CFRP component when initially subjected to the load - environment coupling loading;

[0135] The prediction formula for the change in the electrical conductivity of the moisture - absorbing composite material under the long - term load - environment coupling effect is formula (3):

[0136] ΔG2 t =G2 t -G2 0 =L2 t / (A·ρ2 t )-L2 0 / (A·ρ2 0 ); (3)

[0137] Among them, ΔG2 t is the change in the water absorption rate of the moisture - absorbing CFRP component under the long - term load - environment coupling effect, G2 t is the electrical conductivity of the moisture - absorbing CFRP component under the long - term load - environment coupling effect at service time t, G2 0 is the electrical conductivity of the moisture - absorbing CFRP component when initially subjected to the load - environment coupling loading, L2 t is the length of the moisture - absorbing CFRP component under the long - term load - environment coupling effect at service time t, ρ2 t is the resistance of the moisture - absorbing CFRP component under the long - term load - environment coupling effect at service time t, L2 0 is the length of the moisture - absorbing CFRP component when initially subjected to the load - environment coupling loading, ρ2 0 is the resistance of the moisture - absorbing CFRP component when initially subjected to the load - environment coupling loading.

[0138] As Figures 4 - 5 shown, the resistance measured by the transverse electrode at a certain position of the composite material is expressed as R x, in the transverse direction inside the composite material, a complex series-parallel resistance system is composed of a large number of carbon fibers and resin. This resistance system consists of the resistance of the fibers and the resistance of the transition layer between adjacent fibers. Assuming the above series-parallel system is a system where n resistors are first connected in parallel and then m resistors are connected in series, the parallel resistance of the l-th row can be briefly expressed as:

[0139]

[0140] After all m resistors are connected in series, the measured total transverse resistance can be briefly expressed as:

[0141]

[0142] R nm is the resistance value of the m-th row and n-th column, R l is the resistance of the l-th row, R x is the resistance value of the overall system.

[0143] In this system:

[0144] Stress loading and regulation component: This module is designed to apply precise stress loading to CFRP. It can achieve constant stress or variable stress loading modes to simulate the stress conditions that CFRP may encounter in actual applications. By setting the controller program, this module can achieve automatic control of stress, ensuring the accuracy and repeatability of the experiment.

[0145] Water circulation component: This module provides the necessary salt, heat, and humidity environmental conditions for CFRP, simulating the complex environment in actual applications. Through the integrated temperature regulation module, the environmental conditions can be programmed and automatically controlled, thus ensuring the stability and controllability of the experimental environment.

[0146] Radial resistance monitoring component: This module focuses on monitoring the resistance change parallel to the CFRP fiber direction. Under the coupled action of multiple factors such as force, salt, heat, and humidity, this module can capture the resistance change process in real time, providing key data for evaluating material performance.

[0147] Transverse resistance monitoring component: Corresponding to the radial resistance monitoring module, this module is used to monitor the resistance change perpendicular to the CFRP fiber direction. By monitoring the resistance changes in different directions, a more comprehensive understanding of the damage and performance degradation of the material under the coupled action of multiple factors can be obtained.

[0148] In this method:

[0149] (1) Installation and anchoring: Cut the CFRP into a certain length, paste a conductive sheet or coating at specific positions on the surface, spray a waterproof coating or wrap a water-proofing film on specific parts. The CFRP rod passes through a force sensor, a water circulation component, etc. in sequence, and mechanical clamping anchoring or bonding anchoring is completed at both ends of the CFRP with an anchor.

[0150] (2) Solution injection: Prepare the solution type required for the aging test, inject the solution from the upper water injection port of the water level monitoring pipe until it reaches a certain height in the water level monitoring pipe, set the heating and cooling program of the temperature controller, and run.

[0151] (3) Programming and operation: Set the stress level and other parameters of the stress controller, apply stress to the CFRP according to the set program, and at the same time turn on the resistance recorder to collect the longitudinal and transverse resistance values of the CFRP, and automatically store the resistance value every certain period of time.

[0152] (4) Regular inspection: Observe the water level height in the water level monitoring pipe every certain period of time. If the water level drops, the solution needs to be replenished.

[0153] (5) Empty the solution: After the load environment coupling aging experiment is completed, turn off the heating program of the controller, open the drain valve, and empty the solution in the water circulation component.

[0154] (6) Unload and sample: Unload the prestress, take out the CFRP, cut the part soaked in the solution, and conduct mechanical and physical-chemical property tests on the composite material.

[0155] (7) Data analysis: By comparing and analyzing the corresponding relationship between the mechanical properties and resistance of the CFRP under different force salt heat and humidity experimental conditions, establish an empirical model formula between the resistance and the water absorption rate and mechanical properties of the CFRP, associate the resistance change with the water absorption rate and the attenuation degree of the mechanical properties of the material, and provide a quantitative tool for performance evaluation.

[0156] (8) Prediction of the long-term service life of CFRP: Use the established empirical model formula to predict the water absorption rate and the attenuation degree of the mechanical properties of the CFRP by measuring the resistance.

[0157] The present invention aims to realize the dynamic monitoring of the conductivity, water absorption rate and damage process of the material by real-time monitoring the resistance change law of the CFRP. The system includes a stress loading and regulating component, a radial resistance monitoring component, a water circulation component and a transverse resistance monitoring component. Through long-term resistance monitoring, analysis of the corresponding relationship between mechanical properties and resistance, establishment of an empirical model formula, and estimation of the attenuation degree of mechanical properties, the present invention provides an efficient and non-destructive evaluation method for predicting the service life of the CFRP, guiding maintenance and replacement strategies. The present invention realizes the real-time dynamic monitoring of the conductivity, water absorption rate and damage process of the CFRP under the multi-factor coupling action of force, salt, heat and humidity.

[0158] The present invention establishes an empirical model, providing a scientific basis for evaluating the water absorption rate and the attenuation of mechanical properties of CFRP under long-term multi-factor coupling effects. The present invention provides an efficient and non-destructive evaluation method for the long-term performance monitoring of CFRP. The present invention improves the accuracy of predicting the service life of CFRP, providing guidance for the maintenance and replacement of materials. This has important practical significance for predicting the service life of materials and guiding maintenance and replacement strategies. The water circulation component adopted in the present invention consumes less solution mass, is easy to replace and adjust, and has good experimental convenience.

[0159] The following points need to be explained:

[0160] (1) The attached drawings of the embodiments of the present invention only relate to the structures involved in the embodiments of the present invention, and other structures can refer to the general design.

[0161] (2) For clarity, in the attached drawings used to describe the embodiments of the present invention, the thickness of layers or regions is enlarged or reduced, that is, these drawings are not drawn according to the actual scale. It can be understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element can be "directly" on or under the other element or there can be intermediate elements.

[0162] (3) Without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0163] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A performance resistance monitoring system for a CFRP component with coupled loading of load and environment, characterized in that, Including: A stress loading and regulating component, with both ends of the CFRP component loaded on the stress loading and regulating component, which can apply constant stress or variable stress to the CFRP component. Wherein, the CFRP component is a CFRP plate or a CFRP rod, and a water circulation component, a radial resistance detection component, and a transverse resistance monitoring component are installed on the stress loading and regulating component; A water circulation component, which is used to simulate the usage environment of the CFRP component. Wherein, the water circulation component supports regulating the salt concentration, temperature, and humidity in the usage environment of the CFRP component according to the actual environment. The water circulation component includes a target water pipe, and the CFRP component passes through the target water pipe; A radial resistance detection component, which is used to detect the change in the resistance value of the CFRP component in the first direction, and the first direction is parallel to the fiber direction of the CFRP component; The second-mode first electrode, the second-mode second electrode, and the second-mode third electrode in the radial resistance detection component are evenly spaced and installed on the CFRP component and inside the target water pipe. A CFRP hydrophobic coating is provided on the CFRP component between the second-mode first electrode and the second-mode second electrode in the radial resistance; A transverse resistance detection component, which is used to detect the change in the resistance value of the CFRP component in the second direction, and the second direction is perpendicular to the fiber direction of the CFRP component; The transverse resistance detection component includes a four-mode wet transverse resistance electrode and a four-mode dry transverse resistance electrode. Branches of the four-mode first wire in the transverse resistance detection component are each connected to a four-mode wet transverse resistance electrode, and the four-mode wet transverse resistance electrode is provided on the CFRP component. The tail end of the four-mode second wire in the transverse resistance detection component is provided with m parallel branches, and each branch of the four-mode second wire is connected to a four-mode dry transverse resistance electrode, and the four-mode dry transverse resistance electrode is provided on the CFRP component coated with a four-mode hydrophobic coating.

2. The performance resistance monitoring system for a CFRP component with coupled load and environment loading according to claim 1, characterized in that, The stress loading and regulating component includes: A first-mode fixed base, which is horizontally arranged; A first-mode first fixed bracket and a first-mode second fixed bracket, which are symmetrically installed at both ends of the upper surface of the first-mode fixed base; A first-mode driving component, which is installed on the first-mode fixed base and is arranged on the side of the first-mode second fixed bracket; An anchor, one end of the anchor is installed on the first fixed bracket, the other end of the anchor is installed on the first-mode driving component, and both ends of the CFRP component are installed inside both ends of the anchor; A force measuring sensor, which is installed on the side of the first-mode first fixed bracket and on the anchor; A first-mode controller, which is respectively connected to the force measuring sensor and the first-mode driving component by telecommunications; Wherein, the first-mode driving component supports driving the anchor on the same end side to move in the horizontal direction.

3. The performance resistance monitoring system for CFRP components with coupled load and environment loading according to claim 2, characterized in that The first-mode driving component includes: A servo motor support, which is installed on the surface of the first-mode fixed base; Servo motor, the servo motor is installed on the servo motor support; First gear and second gear, the upper and lower ends of the second gear are respectively meshed with the first gear, and the second gear is connected to the servo motor through a coupling; Screw rods, two screw rods are arranged in parallel, and one ends of the two screw rods are respectively installed at the centers of the two first gears; Support plate, two threaded holes are arranged on the support plate, and the two threaded holes are respectively adapted to the two screw rods. One end of the anchor away from the first fixed bracket of the first die is arranged on the side of the support plate away from the first fixed bracket of the first die, and the CFRP member is installed through the support plate at one end of the anchor away from the first fixed bracket of the first die; When the servo motor drives the second gear to rotate, the second gear drives the two first gears to rotate, and the two first gears respectively drive the corresponding screw rods to rotate, and the support plate moves along the horizontal direction of the screw rods while driving the two ends of the anchor to approach or move away from each other relatively.

4. The performance resistance monitoring system for coupling and loading CFRP members under load environment according to claim 3, characterized in that The target water pipe is arranged above the fixed base of the first die. One end of the target water pipe is blocked by a first silicone plug, and the other end of the target water pipe is blocked by a third silicone plug. The CFRP member sequentially passes through the first silicone plug, the target water pipe and the third silicone plug, and the target water pipe is installed in the target water pipe heat preservation sleeve; The water circulation assembly further includes: Electric heating pipe, an electric heating tape is installed on the outer wall of the electric heating pipe, an electric heating tape heat preservation sleeve is arranged on the outer wall of the electric heating tape, the electric heating tape heat preservation sleeve is installed on the first fixed support and the second fixed support of the electric heating pipe, and the first fixed support and the second fixed support of the electric heating pipe are installed on the upper surface of the fixed base of the first die; Three-mode controller, the three-mode controller is installed on the three-mode controller support, the three-mode controller support is installed on the upper surface of the fixed base of the first die, the three-mode controller is electrically connected to the electric heating tape and the temperature sensor, and the temperature sensor is installed in the target water pipe; First hose, second hose and third hose, one end of the first hose is connected to one end of the electric heating pipe, the other end of the first hose is connected to the circulation water pump, the other end of the circulation water pump is connected to one end of the second hose, the other end of the second hose is connected to the side wall of the end of one end of the target water pipe through a first three-way joint, one end of the third hose is connected to the other end of the electric heating pipe, and the other end of the third hose is connected to the side wall of the end of the other end of the target water pipe through a third three-way joint; Wherein, a first hose heat preservation sleeve is arranged on the first hose, a second hose heat preservation sleeve is arranged on the second hose, a third hose heat preservation sleeve is arranged on the third hose, and the circulation water pump is electrically connected to the three-mode controller; Water level monitoring pipe, the water level monitoring pipe is vertically installed above the target water pipe and is connected to the target water pipe through a second three-way joint, and a second silicone plug is arranged at the end of the water level monitoring pipe; A water discharge valve and a water tank. A fourth three-way joint is arranged on the electric heating pipe and on the same side as the third hose. The fourth three-way joint connects the electric heating pipe and the third hose, and a water discharge valve is arranged at the other end of the fourth three-way joint. A water tank is arranged below the water discharge valve.

5. The performance resistance monitoring system for a CFRP component with coupled load and environment loading according to claim 4, characterized in that, The transverse resistance detection component: A four-mode resistance recorder, which is installed on a four-mode resistance recorder support, and the four-mode resistance recorder support is installed on the first-mode fixed base; The first ends of the four-mode first wire and the four-mode second wire are respectively connected to the four-mode resistance recorder, and the tail end of the four-mode first wire is provided with m parallel branches; A four-mode silicone rubber capillary sleeve, which is installed on the four-mode first wire and the four-mode second wire.

6. The performance resistance monitoring system for a CFRP component with coupled load and environment loading according to claim 5, characterized in that, The radial resistance detection component includes: A two-mode resistance recorder, which is installed on a two-mode resistance recorder support, and the two-mode resistance recorder support is installed on the first-mode fixed base; A two-mode first wire, a two-mode second wire and a two-mode third wire. One end of the two-mode first wire is connected to a two-mode first electrode, the other end of the two-mode first wire is connected to the two-mode resistance recorder, one end of the two-mode second wire is connected to a two-mode second electrode, the other end of the two-mode second wire is connected to the two-mode resistance recorder, one end of the two-mode third wire is connected to a two-mode third electrode, and the other end of the two-mode third wire is connected to the two-mode resistance recorder. Two-mode silicone rubber capillary sleeves are arranged on the wire bodies of the two-mode first wire, the two-mode second wire and the two-mode third wire; Wherein, the two-mode first electrode, the two-mode second electrode and the two-mode third electrode have the same structure.

7. The performance resistance monitoring system for a CFRP component with coupled load and environment loading according to claim 6, characterized in that, The two-mode first electrode includes: a metal electrode, a highly conductive adhesive and an electrode hydrophobic coating; The metal electrode is installed on the CFRP part through the highly conductive adhesive; The surface of the metal electrode is coated with an electrode hydrophobic coating.

8. The performance resistance monitoring system for a CFRP component with coupled load and environment loading according to claim 4, characterized in that, The electric heating tape is a glass fiber tracing tape, a carbon fiber heating tape or a silicone rubber tracing tape.

9. A performance resistance monitoring method for a CFRP component under coupled loading of load and environment, characterized in that, Applied to the performance resistance monitoring system of the load environment coupled loading CFRP part described in claim 7, including: Install the CFRP part on the anchor. Among them, conductive sheets and coatings are pre-arranged on the CFRP part according to preset requirements; After adding a solution into the target water pipe from the water level monitoring pipe until the target height is reached according to preset requirements, adjust the temperature in the target water pipe through the water circulation component; Adjust the stress on the CFRP part based on the stress loading control component; Every preset time period, collect the resistance values on the two-mode resistance recorder and the four-mode resistance recorder once and upload the collected values to the upper computer; Among them, regularly detect the water level height in the water level monitoring pipe. If it is lower than the preset water level height, supplement the solution; When the number of times of resistance value detection reaches the preset requirements, the electric heating pipe stops working, discharge the solution through the water discharge valve, and unload the stress applied on the CFRP part through the stress loading control component; An empirical model between the resistance, the water absorption rate of the CFRP component, and the mechanical properties of the CFRP component is obtained based on the data of the two-mode resistance recorder, the data of the four-mode resistance recorder, and the parameters of the solution.

10. The performance resistance monitoring method for the load environment coupled loading CFRP member according to claim 9, wherein The empirical model between the resistance, the water absorption rate of the CFRP component, and the mechanical properties of the CFRP component includes: The influence of the water absorption rate on the conductivity of the CFRP component is given by Equation (1): ∆G water = G2 - G1 = L2 / (A ∙ ρ2) - L1 / (A ∙ ρ1); (1) where ∆G wate is the change in the electrical conductivity of CFRP caused by moisture absorption, G1 is the electrical conductivity of the non-moisture-absorbing section, G2 is the electrical conductivity of the moisture-absorbing section, A is the cross-sectional area of CFRP, ρ1 is the resistivity of the non-moisture-absorbing section, ρ2 is the resistivity of the moisture-absorbing section, L1 is the length of the non-moisture-absorbing section, and L2 is the length of the moisture-absorbing section; The change in the conductivity of the composite material in the non-moisture absorption section under the coupled action of the long-term load environment is given by Equation (2): ∆G1 t =G1 t -G1 0 =L1 t / ( A ∙ρ1 t )- L1 0 / ( A ∙ρ1 0 );(2) Among them, ∆G1 t is the change in water absorption rate under the long-term load-environment coupling action of the non-hydroscopic CFRP component, G1 t is the conductivity of the non-hydroscopic CFRP component at the service time t under the long-term load-environment coupling action, G1 0 is the conductivity of the non-hydroscopic CFRP component at the initial load-environment coupling loading, L1 t is the length of the non-hydroscopic CFRP component at the service time t under the long-term load-environment coupling action, ρ1 t is the resistance of the non-hydroscopic CFRP component at the service time t under the long-term load-environment coupling action, L1 0 is the length of the non-hydroscopic CFRP component at the initial load-environment coupling loading, ρ1 0 is the resistance of the non-hydroscopic CFRP component at the initial load-environment coupling loading; The prediction formula for the change in the conductivity of the composite material in the moisture absorption section under the coupled action of the long-term load environment is given by Equation (3): ∆G2 t =G2 t -G2 0 =L2 t / ( A ∙ρ2 t )-L2 0 / ( A ∙ρ2 0 );(3) Among them, ∆G2 t is the change in water absorption rate of the CFRP component in the moisture absorption section under the long-term load-environment coupling effect, G2 t is the conductivity of the CFRP component in the moisture absorption section at the service time t under the long-term load-environment coupling effect, G2 0 is the conductivity of the CFRP component in the moisture absorption section at the initial load-environment coupling loading, L2 t is the length of the CFRP component in the moisture absorption section at the service time t under the long-term load-environment coupling effect, ρ2 t is the resistance of the CFRP component in the moisture absorption section at the service time t under the long-term load-environment coupling effect, L2 0 is the length of the CFRP component in the moisture absorption section at the initial load-environment coupling loading, ρ2 0 is the resistance of the CFRP component in the moisture absorption section at the initial load-environment coupling loading.

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