A composite material structure strength analysis method considering hollow fiber damage

Abstract

The present application relates to the technical fields of composite material mechanics and structure engineering, and discloses a composite material structure strength analysis method considering hollow fiber damage, establishes a composite material hollow fiber damage simulation model, and sets a composite material data acquisition module, a hollow fiber damage simulation module, a hollow fiber damage analysis module, a hollow fiber damage evaluation module and a composite material model upgrading module in the model, calculates the external factor damage hollow fiber probability, the internal factor damage hollow fiber probability and the composite material matrix damage degree through the hollow fiber damage analysis module, simulates the crack propagation direction and rate under different stress fields according to the hollow fiber damage simulation module, generates a crack propagation path diagram, enables the hollow fiber damage evaluation module to accurately predict the crack propagation path, the fiber fracture position and the interface debonding risk, so that maintenance measures can be taken in advance to reduce the risk of composite material structure failure caused by damage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite material mechanics and structural engineering, in particular to a composite material structure strength analysis method considering hollow fiber damage. BACKGROUND

[0002] In the field of composite material structure application, hollow fiber damage is one of the key factors affecting the strength and reliability of the structure. With the wide application of composite materials in aerospace, automobile manufacturing, wind power generation, building reinforcement and other fields, the safety and reliability of the structure are directly related to the safe operation and economic benefits of the project. Hollow fiber damage not only reduces the mechanical properties of the material, but also may cause early failure of the structure, and even cause safety accidents. Therefore, accurately evaluating the hollow fiber damage and its evolution process, and ensuring the safe and stable operation of the structure, have become key problems to be solved in the industry.

[0003] The existing damage evaluation methods have many limitations. First, these methods are difficult to comprehensively consider the influence of external loads (such as complex stress field, environmental factors) and internal defects (such as fiber diameter deviation, porosity, fiber arrangement angle, etc.) on damage. In actual application, composite material structures are often under complex working conditions and are affected by multiple factors, while the existing methods cannot accurately predict the crack propagation path, fiber fracture position and interface debonding risk, resulting in large prediction error and inability to accurately predict structure failure in advance.

[0004] Secondly, the existing simulation model does not establish a dynamic optimization mechanism. Under different working conditions, such as temperature and humidity changes, load type changes, etc., the accuracy of the model fluctuates greatly, and it is difficult to continuously and reliably support damage evaluation and design optimization. This instability makes it difficult for engineers to rely on model results to make decisions in actual application, increasing engineering risk.

[0005] In addition, the existing damage evaluation method lacks a multi-dimensional data acquisition and quantitative evaluation system. Historical damage data and real-time operation data cannot be effectively integrated, resulting in ambiguity in damage degree determination and lack of targetedness in maintenance measures. This situation not only increases maintenance costs, but also makes structure life management more extensive and cannot achieve fine management.

[0006] Therefore, there is an urgent need for a composite material structure strength analysis method that can accurately evaluate damage by considering multiple factors, dynamically optimize the model, and efficiently manage and maintain the structure. This method can solve the pain points of existing technology in damage prediction, model reliability and engineering application economy, and improve the safety and economy of the whole life cycle of the composite material structure. SUMMARY

[0007] In response to the shortcomings of the existing technology, the present invention provides a composite material structural strength analysis method taking into account hollow fiber damage. It has the advantages of multi-factor collaborative accurate prediction, dynamic adaptive optimization of the model, and multi-dimensional data-driven efficient maintenance. It solves the problems of large damage prediction errors, poor adaptability of model working conditions, and lack of targeted maintenance management in traditional methods.

[0008] To achieve the above object, the present invention provides the following technical solution: a composite material structure strength analysis method considering hollow fiber damage, comprising the following steps:

[0009] Step 1: Establish a composite hollow fiber damage simulation model, and set up a composite material data acquisition module, a hollow fiber damage simulation module, a hollow fiber damage analysis module, a hollow fiber damage assessment module, and a composite material model upgrade module in the model;

[0010] Step 2: The composite material data acquisition module is responsible for collecting historical data, current data, material structure data, structural data affecting damage, and external force data;

[0011] Step 3: The hollow fiber damage simulation module simulates the damage evolution process of the hollow fiber under external load based on the input data of the composite material data acquisition module and the composite material mechanics theory;

[0012] Step 4: Hollow fiber damage analysis module uses the simulation data of hollow fiber damage simulation module and the collected data to calculate the probability of hollow fiber damage caused by external factors. , Probability of internal factors damaging hollow fibers , the degree of damage to the composite matrix With simulation accuracy Calculation of

[0013] Step 5: Hollow fiber damage assessment module determines the probability of hollow fiber damage based on external factors. The probability of hollow fiber damage caused by internal factors Comprehensive evaluation, by simulating the crack propagation direction and rate under different stress fields, generating a crack propagation path diagram to predict the crack propagation path and fiber fracture position; according to the degree of damage to the composite material matrix , combined with the simulated fiber fracture location, to predict the risk of interface debonding;

[0014] Step 6: The composite material model upgrade module optimizes the composite material hollow fiber damage simulation model according to the simulation accuracy and damage assessment results calculated by the hollow fiber damage analysis module.

[0015] Preferably, the composite material data acquisition module includes a historical damage data unit, a monitoring data unit and a material structure data unit.

[0016] Preferably, the historical damage data unit queries the historical damage data through a database query interface or a cloud data platform.

[0017] Preferably, the monitoring data unit obtains real-time operation data of the composite material structure through a sensor network and a wireless network.

[0018] Preferably, the material structure data unit obtains the structural parameters of the composite material itself through microscope imaging analysis and a material testing machine, and records structural damage impact data.

[0019] Preferably, the hollow fiber damage analysis module calculates the probability of hollow fiber damage caused by external factors based on historical damage data and real-time operation data of the composite material structure. , and its calculation formula is:

[0020] ;

[0021] In the formula, Indicates the probability of external factors damaging the hollow fiber, Indicates the The maximum stress in the cycle, Indicates the The minimum stress in the cycle, Indicates the The critical stress in the second cycle, Indicates the The maximum strain degree in the cycle, Indicates the The minimum strain level in the cycle, Indicates the The critical strain level in the sub-cycle, Indicates the total number of cycles.

[0022] Preferably, the hollow fiber damage analysis module calculates the probability of internal factors damaging the hollow fiber based on the structural parameters of the composite material itself and the real-time operation data of the composite material structure. , and its calculation formula is:

[0023] ;

[0024] In the formula, represents the probability of damage caused by internal factors, represents the standard deviation of the fiber diameter distribution inside the composite material, Indicates the angle deviation of the fiber arrangement inside the composite material. represents the matrix elastic modulus of the composite material, represents the internal porosity of the composite material, Indicates the stress inside the hollow fiber, 、 They represent the weight coefficients of the fiber diameter and arrangement angle inside the composite material respectively.

[0025] Preferably, the hollow fiber damage analysis module is based on the probability of damage to the hollow fiber caused by internal factors. Calculating the degree of damage to composite matrix , and its calculation formula is:

[0026] ;

[0027] In the formula, Indicates the degree of damage to the composite matrix. represents the probability of damage caused by internal factors, Indicates the current plastic strain degree of the matrix, Indicates the degree of matrix failure strain, represents the damage evolution coefficient, represents the damage acceleration index, Represents the base of a natural constant.

[0028] Preferably, the hollow fiber damage analysis module calculates the simulation accuracy , and its calculation formula is:

[0029] ;

[0030] In the formula, Indicates the simulation accuracy, Indicates the The simulated crack extension length value obtained by group simulation calculation is Indicates the The crack extension length values ​​obtained from the experimental group are Indicates the number of sample groups for validation data.

[0031] Compared with the prior art, the present invention provides a composite material structural strength analysis method taking hollow fiber damage into consideration, which has the following beneficial effects:

[0032] 1. The present invention comprehensively evaluates the probability of external factors damaging the hollow fiber , Probability of internal factors damaging hollow fibers The damage degree of composite matrix , achieving the beneficial effect of accurately predicting the crack propagation path, fiber fracture location and interface debonding risk. Among them, the hollow fiber damage assessment module combines the probability of hollow fiber damage caused by external factors , Probability of internal factors damaging hollow fibers By simulating the crack propagation direction and rate under different stress fields, a crack propagation path diagram is generated to predict the crack propagation path and fiber fracture position; at the same time, according to the degree of damage to the composite matrix , combined with the simulated fiber fracture location, the risk of interface debonding is predicted. By accurately predicting the damage state, maintenance measures can be taken in advance to reduce the risk of structural failure caused by damage, thereby improving the safety and reliability of composite structures.

[0033] 2. The present invention simulates the accuracy through dynamic calculation And take corresponding optimization measures according to the accuracy range, achieving the beneficial effect of continuously improving the accuracy and reliability of the simulation model. Among them, the hollow fiber damage analysis module calculates the simulation accuracy Through small-scale simulation accuracy tests, different measures are taken according to the simulation accuracy range to dynamically optimize the simulation model to ensure that it can maintain high accuracy and high reliability under different working conditions, providing strong support for damage assessment and optimization design of composite structures.

[0034] 3. The present invention achieves the beneficial effect of efficient management and maintenance of composite material structures by establishing a composite material data acquisition module and a three-level evaluation standard. Among them, the composite material data acquisition module includes a historical damage data unit, a monitoring data unit and a material structure data unit. Through different units, historical data, current data, material structure data, structural data affecting damage and external force data are collected to provide multi-dimensional data source support for subsequent modules, and the degree of damage to the composite material matrix is ​​quantitatively evaluated. , to establish a three-level assessment standard, take targeted maintenance measures according to different degrees of damage, and ultimately achieve efficient management and maintenance of composite materials structures through multi-dimensional data collection and quantitative evaluation, so as to reduce maintenance costs and thus improve the economic benefits of engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Flow chart of the method of the present invention;

[0036] Figure 2 This is a flow chart of safety monitoring of a building composite material reinforcement structure according to Example 4 of the present invention;

[0037] Figure 3 This is a flow chart of safety monitoring of building composite material reinforcement structure in comparative example 4 of the present invention. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] See also Figure 1-Figure 3 A composite material structure strength analysis method considering hollow fiber damage includes the following steps:

[0040] Step 1: Establish a composite hollow fiber damage simulation model, and set up a composite material data acquisition module, a hollow fiber damage simulation module, a hollow fiber damage analysis module, a hollow fiber damage assessment module, and a composite material model upgrade module in the model;

[0041] Step 2: The composite material data acquisition module is responsible for collecting historical data, current data, material structure data, structural data affecting damage, and external force data, providing multi-dimensional data source support for subsequent modules;

[0042] Step 3: The hollow fiber damage simulation module simulates the damage evolution process of the hollow fiber under external load based on the input data of the composite material data acquisition module and the composite material mechanics theory;

[0043] Step 4: Hollow fiber damage analysis module uses the simulation data of hollow fiber damage simulation module and the collected data to calculate the probability of hollow fiber damage caused by external factors. , Probability of internal factors damaging hollow fibers , the degree of damage to the composite matrix With simulation accuracy The above calculations help to judge the reliability of the model and provide a basis for subsequent evaluation;

[0044] Step 5: Hollow fiber damage assessment module determines the probability of hollow fiber damage based on external factors. The probability of hollow fiber damage caused by internal factors Comprehensive evaluation, by simulating the crack propagation direction and rate under different stress fields, generating a crack propagation path diagram to predict the crack propagation path and fiber fracture position; according to the degree of damage to the composite material matrix , combined with the simulated fiber fracture location, to predict the risk of interface debonding;

[0045] Step 6: The composite material model upgrade module optimizes the composite material hollow fiber damage simulation model according to the simulation accuracy and damage assessment results calculated by the hollow fiber damage analysis module.

[0046] The composite material data acquisition module includes historical damage data unit, monitoring data unit and material structure data unit.

[0047] The historical damage data unit queries historical damage data through the database query interface or cloud data platform, including the number of fatigue cycles and damage repair records of composite materials.

[0048] The monitoring data unit obtains real-time operating data of the composite material structure through the sensor network and wireless network, including the current operating load, ambient temperature and stress / strain distribution of the composite material.

[0049] The material structure data unit obtains the structural parameters of the composite material itself through microscope imaging analysis and material testing machine, including fiber diameter, resin matrix elastic modulus and fiber / matrix interface strength, and records the impact data of structural damage, including fiber arrangement angle, porosity and interlayer thickness.

[0050] The hollow fiber damage analysis module calculates the probability of hollow fiber damage caused by external factors based on historical damage data and real-time operation data of composite structures. , and its calculation formula is:

[0051] ;

[0052] In the formula, Indicates the probability of external factors damaging the hollow fiber, Indicates the The maximum stress in the cycle, Indicates the The minimum stress in the cycle, Indicates the The critical stress in the second cycle, Indicates the The maximum strain degree in the cycle, Indicates the The minimum strain level in the cycle, Indicates the The critical strain level in the sub-cycle, Indicates the total number of cycles.

[0053] Advantages: By calculating the probability of external factors damaging the hollow fiber , taking this value as the core criterion for structural safety warning, when the probability of external factors damaging the hollow fiber When the value is between 0 and 0.3, it is a low-risk range. The model will automatically trigger the routine monitoring process. It only needs to review the damage status through ultrasonic scanning every quarter and maintain the default parameters of the model. When the probability of hollow fiber damage is high due to external factors, the model will automatically trigger the routine monitoring process. When the value is between 0.3 and 0.65, it is a medium-risk range. The model will automatically start the active protection strategy to reduce the operating load or optimize the ambient temperature control. At the same time, the model will automatically activate the "load-damage" association intensive training. When the external factors damage the hollow fiber probability When it is greater than 0.65, it belongs to the high-risk range. The model automatically executes the emergency maintenance plan, shutting down for inspection or local reinforcement. The model is forced to call the historical failure case library to reconstruct the damage evolution path, so that the simulation model's prediction error for extreme working conditions is reduced.

[0054] The hollow fiber damage analysis module calculates the probability of internal factors damaging the hollow fiber based on the structural parameters of the composite material itself and the real-time operation data of the composite material structure. , and its calculation formula is:

[0055] ;

[0056] In the formula, represents the probability of damage caused by internal factors, represents the standard deviation of the fiber diameter distribution inside the composite material, Indicates the angle deviation of the fiber arrangement inside the composite material. represents the matrix elastic modulus of the composite material, represents the internal porosity of the composite material, Indicates the stress inside the hollow fiber, and They represent the weight coefficients of the fiber diameter and arrangement angle inside the composite material respectively.

[0057] Advantages: By calculating the probability of internal factors damaging the hollow fiber , as a quantitative indicator of the intrinsic defects of the material, when the internal factors damage the hollow fiber probability In the range of 0-0.35, it belongs to the repairable range. Currently, resin penetration repair measures are used to fill it, and the mapping relationship of "fiber diameter deviation-damage threshold" in the model is adjusted synchronously. When the internal factors damage the hollow fiber probability When it is greater than 0.35, it belongs to the unrepairable range. The model will automatically trigger the structural part replacement process and input the newly collected internal diameter distribution and arrangement deviation of the composite material into the model parameter library, which greatly improves the simulation model's recognition accuracy of internal defects.

[0058] Hollow fiber damage analysis module damages the hollow fiber according to internal factors Calculating the degree of damage to composite matrix , and its calculation formula is:

[0059] ;

[0060] In the formula, Indicates the degree of damage to the composite matrix. represents the probability of damage caused by internal factors, Indicates the current plastic strain degree of the matrix, Indicates the degree of matrix failure strain, represents the damage evolution coefficient, which is determined by the material toughness. Indicates the damage acceleration index, which reflects the damage expansion rate. Represents the base of a natural constant.

[0061] Advantages: Hollow fiber damage analysis module can be used to determine the probability of hollow fiber damage based on internal factors. Calculating the degree of damage to composite matrix , conduct quantitative evaluation and establish a three-level evaluation standard. When the damage degree of the composite material matrix is ​​within the preset range of [0,0.15], it means that the current damage degree is low and can continue to be used. When the damage degree of the composite material matrix is ​​within the range of [0.15,0.45], it means that the current damage degree is medium and the composite material needs to be repaired immediately; when the damage degree of the composite material matrix is ​​within the range of [0.45,1], it means that the current damage degree is high and the composite material cannot continue to be used and needs to be replaced. The above measures enable composite materials to be better used in actual operations.

[0062] Hollow fiber damage analysis module calculation simulation accuracy , and its calculation formula is:

[0063] ;

[0064] In the formula, Indicates the simulation accuracy, Indicates the The simulated crack extension length value obtained by group simulation calculation is Indicates the The crack extension length values ​​obtained from the experimental measurements are: Indicates the number of sample groups for validation data. (For example, if 10 groups of damage data under different loads are collected, m=10).

[0065] Advantages: The simulation accuracy is calculated by the hollow fiber damage analysis module Before the simulation test, a small-scale simulation accuracy test was conducted. When the simulation results are in the range of [0.8,1], it means that the simulation results are consistent with the experimental data. The simulation is continued. When the value is in the range of [0.5, 0.8), it indicates that the simulation results have certain deviations. The following measures need to be taken to optimize the current simulation model, check and adjust the elastic modulus and Poisson's ratio of the composite material in the simulation model, eliminate abnormal parameters, and enable the simulation model to achieve high accuracy and high reliability, providing strong support for damage assessment and optimization design of composite structures.

[0066] Hollow fiber damage assessment module is based on the probability of damage to hollow fibers caused by external factors. The probability of hollow fiber damage caused by internal factors Comprehensive evaluation, by simulating the crack propagation direction and rate under different stress fields, generating a crack propagation path diagram to predict the crack propagation path and fiber fracture position; according to the degree of damage to the composite material matrix , combined with the simulated fiber fracture location, to predict the risk of interface debonding;

[0067] Composite material model upgrade module according to simulation accuracy The model is further updated and optimized based on the results of the damage assessment, and new experimental data and actual operation data are regularly added to continuously improve the accuracy and reliability of the model.

[0068] The method of the present invention was applied to four different scenarios, and the following data were obtained:

[0069] Example 1 (Aerospace Wing Structural Damage Analysis)

[0070] In the aerospace field, a certain model of passenger aircraft wings is manufactured using composite materials. The composite material data acquisition module, using a database query interface, retrieved fatigue cycle data from the wing model's past 500 flights and discovered three minor damage repairs. The monitoring data unit's sensors reported in real time that the current flight load was 8,000N, the ambient temperature was -30°C, and the strain in the stress concentration area reached 0.005. Testing of the material structure data unit revealed a fiber diameter of 7μm, a resin matrix elastic modulus of 3.5GPa, a fiber / matrix interface strength of 45MPa, a fiber arrangement angle deviation of 5°, and a porosity of 1.2%.

[0071] The hollow fiber damage simulation module combines this data to simulate the damage evolution trend of the hollow fiber under the current flight load. The hollow fiber damage analysis module calculates the probability of external damage to the hollow fiber to be 0.4, which is in the medium-risk range; the probability of internal damage to the hollow fiber is 0.25, which is in the repairable range. Based on this, the model automatically initiates an active protection strategy, reducing the flight load to 7000N and optimizing cabin temperature control. At the same time, resin infiltration is used to repair internal damage. After adjusting model parameters, the hollow fiber damage assessment module predicts that cracks may extend along the fiber arrangement direction in the stress concentration area, and formulates a maintenance plan in advance to ensure flight safety.

[0072] Comparative Example 1

[0073] In the same aerospace wing structure, traditional damage assessment methods are used to monitor the damage status only through regular ultrasonic testing and manual inspections. Due to the lack of real-time data collection and dynamic simulation, the damage risk in the stress concentration area cannot be discovered in time. During a flight, cracks propagate in the wing, resulting in an emergency grounding and maintenance, which increases maintenance costs and downtime.

[0074] Example 2 (Diagnosis and Maintenance of Wind Turbine Blade Damage)

[0075] For a large wind turbine blade at a certain wind farm, the composite material data acquisition module obtains fatigue cycle data from the cloud platform for its historical operation of 1000 hours, with no major maintenance records. The monitoring data unit monitors in real time that the current wind load borne by the blade is 5000N, the ambient temperature is 25°C, and the stress / strain distribution shows that the stress at the blade tip is relatively large. The material structure data unit detects that the fiber diameter is 8μm, the resin matrix elastic modulus is 3.2GPa, the fiber / matrix interface strength is 42MPa, the fiber arrangement angle deviation is 3°, and the porosity is 1.5%.

[0076] Calculated by the hollow fiber damage analysis module, the probability of hollow fiber damage due to external factors is 0.2, which is in the low-risk range. The model triggers the routine monitoring process and performs ultrasonic scanning every quarter. The probability of hollow fiber damage due to internal factors is 0.3, which is in the repairable range, and resin penetration repair is implemented. The hollow fiber damage assessment module predicts that under the action of long-term wind loads, there is a risk of fiber breakage at the blade tip, and maintenance personnel are arranged in advance to pay attention to it, thereby extending the service life of the wind turbine blade.

[0077] Comparative Example 2

[0078] In the same wind turbine blade, the traditional monitoring method is used to assess the damage status only through regular ultrasonic testing. Due to the lack of comprehensive assessment of internal factors, the risk of fiber breakage at the blade tip cannot be discovered in time. During a strong wind weather, fiber breakage occurred at the blade tip, causing blade damage, increasing maintenance costs and downtime.

[0079] Example 3 (Evaluation of Automobile Composite Body Structure)

[0080] In automobile manufacturing, the composite body of a certain electric vehicle has a historical damage data unit that found two minor damage repair records in previous collision tests. The monitoring data unit collects in real time the load borne by the vehicle body when driving, which is 2000N, the ambient temperature is 30°C, and the stress / strain distribution shows that the stress at the door connection is high. The material structure data unit detects that the fiber diameter is 6μm, the resin matrix elastic modulus is 3.8GPa, the fiber / matrix interface strength is 48MPa, the fiber arrangement angle deviation is 2°, and the porosity is 1.0%.

[0081] The calculated probability of damage to the hollow fiber from external factors was 0.15, placing it in the low-risk range; the probability of damage from internal factors was 0.32, placing it in the repairable range. The model was maintained according to routine monitoring procedures, while resin infiltration repairs were performed on the door joints. The hollow fiber damage assessment module predicted that crack propagation would occur at the door joints in the event of a collision. This information allowed the automaker to strengthen the structural design of this area, improving vehicle safety.

[0082] Comparative Example 3

[0083] Traditional damage assessment methods for composite vehicle body structures, using only post-crash inspections and simple ultrasonic testing to assess damage, lack a comprehensive assessment of internal factors and fail to promptly identify potential cracks at the door joint. In one crash, a crack propagated at the door joint, causing structural damage, increased repair costs, and increased safety risks.

[0084] Example 4 (Safety Monitoring of Building Composite Material Reinforced Structures)

[0085] In a building reinforcement project, a bridge was reinforced with composite materials. The historical damage data unit captured usage data from the three years following the reinforcement, showing no damage or repair history. The monitoring data unit monitored the bridge in real time, observing a vehicle load of 10,000 N at an ambient temperature of 15°C. The stress / strain distribution showed stress concentration at the pier joints. The material structure data unit determined a fiber diameter of 9 μm, a resin matrix elastic modulus of 3.0 GPa, a fiber / matrix interface strength of 40 MPa, a fiber arrangement angle deviation of 4°, and a porosity of 1.8%.

[0086] The hollow fiber damage analysis module calculated that the probability of hollow fiber damage due to external factors was 0.68, which was in the high-risk range; the probability of hollow fiber damage due to internal factors was 0.38, which was in the irreparable range. The model automatically executed the emergency maintenance plan, shut down the bridge for inspection, replaced the damaged composite structural parts, and entered the newly collected material parameters into the model parameter library. The hollow fiber damage assessment module predicted that the cracks might expand rapidly, endangering the safety of the bridge. Timely treatment avoided potential accidents.

[0087] Comparative Example 4

[0088] In the same building reinforcement structure, traditional monitoring methods were used to assess the damage status only through regular visual inspections and simple ultrasonic testing. Due to the lack of real-time data collection and dynamic simulation, high-risk damage at the pier connections was not discovered in time. When a heavy-loaded vehicle passed through, cracks at the pier connections quickly expanded, causing local damage to the bridge, increasing maintenance costs and safety hazards.

[0089] Summary: The present invention improves the accuracy and reliability of damage prediction for composite structures by comprehensively evaluating the impact of internal and external factors on hollow fiber damage and dynamically optimizing the simulation model. In the four fields of aerospace, wind power, automobile manufacturing, and building reinforcement, this method can effectively ensure the safe operation of composite structures, extend their service life, and reduce maintenance costs. Compared with traditional damage assessment methods, the present invention can detect potential damage risks in advance and take targeted maintenance measures, thereby avoiding structural failure and safety accidents caused by damage.

[0090] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A composite material structural strength analysis method considering hollow fiber damage, characterized in that: The following steps are involved: Step 1: Establish a composite hollow fiber damage simulation model, and set up a composite material data acquisition module, a hollow fiber damage simulation module, a hollow fiber damage analysis module, a hollow fiber damage assessment module, and a composite material model upgrade module in the model; Step 2: The composite material data acquisition module is responsible for collecting historical data, current data, material structure data, structural data affecting damage, and external force data; Step 3: The hollow fiber damage simulation module simulates the damage evolution process of the hollow fiber under external load based on the input data of the composite material data acquisition module and the composite material mechanics theory; Step 4: Hollow fiber damage analysis module uses the simulation data of hollow fiber damage simulation module and the collected data to calculate the probability of hollow fiber damage caused by external factors. , Probability of internal factors damaging hollow fibers , the degree of damage to the composite matrix With simulation accuracy Calculation of Step 5: Hollow fiber damage assessment module determines the probability of hollow fiber damage based on external factors. The probability of hollow fiber damage caused by internal factors Comprehensive evaluation, by simulating the crack propagation direction and rate under different stress fields, generating a crack propagation path diagram to predict the crack propagation path and fiber fracture position; according to the degree of damage to the composite material matrix , combined with the simulated fiber fracture location, to predict the risk of interface debonding; Step 6: The composite material model upgrade module optimizes the composite material hollow fiber damage simulation model according to the simulation accuracy and damage assessment results calculated by the hollow fiber damage analysis module.

2. The composite material structural strength analysis method considering hollow fiber damage according to claim 1, characterized in that: The composite material data acquisition module includes a historical damage data unit, a monitoring data unit and a material structure data unit.

3. The composite material structural strength analysis method considering hollow fiber damage according to claim 2, characterized in that: The historical damage data unit queries historical damage data through a database query interface or a cloud data platform.

4. The composite material structural strength analysis method considering hollow fiber damage according to claim 2, characterized in that: The monitoring data unit obtains real-time operation data of the composite material structure through the sensor network and the wireless network.

5. The composite material structure strength analysis method considering hollow fiber damage according to claim 2, characterized in that: The material structure data unit obtains the structural parameters of the composite material itself through microscope imaging analysis and material testing machine, and records the structural damage impact data.

6. The composite material structure strength analysis method considering hollow fiber damage according to claim 1, characterized in that: The hollow fiber damage analysis module calculates the probability of hollow fiber damage caused by external factors based on historical damage data and real-time operation data of the composite material structure. , and its calculation formula is: ； In the formula, Indicates the probability of external factors damaging the hollow fiber, Indicates the The maximum stress in the cycle, Indicates the The minimum stress in the cycle, Indicates the The critical stress in the second cycle, Indicates the The maximum strain degree in the cycle, Indicates the The minimum strain level in the cycle, Indicates the The critical strain level in the sub-cycle, Indicates the total number of cycles.

7. The composite material structure strength analysis method considering hollow fiber damage according to claim 1, characterized in that: The hollow fiber damage analysis module calculates the probability of internal factors damaging the hollow fiber based on the structural parameters of the composite material itself and the real-time operation data of the composite material structure. , and its calculation formula is: ； In the formula, represents the probability of damage caused by internal factors, represents the standard deviation of the fiber diameter distribution inside the composite material, Indicates the angle deviation of the fiber arrangement inside the composite material. represents the matrix elastic modulus of the composite material, represents the internal porosity of the composite material, Indicates the stress inside the hollow fiber, 、 They represent the weight coefficients of the fiber diameter and arrangement angle inside the composite material respectively.

8. The composite material structure strength analysis method considering hollow fiber damage according to claim 1, characterized in that: The hollow fiber damage analysis module determines the probability of hollow fiber damage based on internal factors. Calculating the degree of damage to composite matrix , and its calculation formula is: ； In the formula, Indicates the degree of damage to the composite matrix. represents the probability of damage caused by internal factors, Indicates the current plastic strain degree of the matrix, Indicates the degree of matrix failure strain, represents the damage evolution coefficient, represents the damage acceleration index, Represents the base of a natural constant.

9. The composite material structure strength analysis method considering hollow fiber damage according to claim 1, characterized in that: The hollow fiber damage analysis module calculates the simulation accuracy , and its calculation formula is: ； In the formula, Indicates the simulation accuracy, Indicates the The simulated crack extension length value obtained by group simulation calculation is Indicates the The crack extension length values ​​obtained from the experimental measurements are: Indicates the number of sample groups for validation data.

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