A corrosion-mechanical coupling in-situ loading anchor rod performance test system

Abstract

The application discloses a kind of corrosion-mechanical coupling in-situ loading's anchor rod performance test system, belong to anchor rod performance test technical field.The application is by being arranged between the upper and lower clamps of fatigue testing machine, realize the in-situ test of anchor rod under the synchronous action of salt fog corrosion and axial load, apply constant load, cyclic load or impulse type disturbance load, simulate the influence of mining disturbance and corrosion environment suffered in the long-term support process of anchor rod;Adjusting salt concentration, pH value, temperature and humidity and spray cycle, spraying mode and dry-wet cycle, realize acid / neutral / alkaline, high temperature and high humidity and water erosion environment simulation and accelerated corrosion, environment warehouse is independently installed by adjustable support, does not bear the axial test load of anchor rod, cooperate upper and lower dynamic sealing piece to ensure loading accuracy and reduce salt fog leakage, corrosion and mechanical parameters are synchronously collected by control and data acquisition system, provide basis for evaluating complex environment anchor rod corrosion rate, corrosion mechanism, damage evolution and residual life.

Description

Technical Field

[0001] This invention relates to the field of anchor bolt performance testing technology, and in particular to an anchor bolt performance testing system based on corrosion-mechanical coupling in-situ loading. Background Technology

[0002] As a primary support component in coal mine roadways, tunnels, and underground engineering, anchor bolts are subjected to various mechanical stresses during long-term service, including groundwater erosion, changes in environmental temperature and humidity, and stress disturbances in the surrounding rock. Their actual working conditions extend beyond static tension, potentially encompassing torsion, cyclic fatigue, and impact disturbances. Under the combined effects of high stress and strong corrosion, anchor bolts are prone to corrosion fatigue damage, leading to decreased load-bearing capacity, reduced toughness and deformation capacity, and shortened support life, seriously threatening the safety, stability, and reliability of underground engineering projects.

[0003] Existing anchor bolt performance testing methods often separate mechanical loading from corrosion environment simulation. Fatigue testing machines are mainly used to apply constant loads, cyclic loads, or pulsed disturbance loads to anchor bolts, but they usually do not have an in-situ salt spray corrosion environment; although salt spray test chambers can simulate corrosive media, they are difficult to apply axial loads simultaneously, and cannot truly reflect the coupling effect of corrosion and mechanical loads.

[0004] In addition, existing devices also have problems such as the salt spray environment chamber bearing the axial test load of the sample, which affects the accuracy of load and displacement measurement; difficulty in sealing the anchor bolt penetration point, leading to salt spray leakage; unstable environmental temperature, humidity and salt spray deposition conditions; incomplete treatment of exhaust gas and waste liquid; and difficulty in synchronously collecting corrosion and mechanical parameters. These problems make it difficult to accurately assess the corrosion rate, damage evolution process, remaining life and failure time of the anchor bolt in the actual mine corrosion environment. Summary of the Invention

[0005] The purpose of this invention is to provide an anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A corrosion-mechanical coupled in-situ loading anchor performance testing system includes a fatigue testing machine, an anchor sample, a salt spray environment chamber, a salt spray generating device, a control and data acquisition system, an exhaust gas purification device, and a waste liquid collection device. The fatigue testing machine includes a testing frame, a servo actuator, an upper clamp, a lower clamp, and a load detection component. The salt spray environment chamber is located between the upper and lower clamps. Both ends of the anchor sample pass through the salt spray environment chamber and are connected to the upper and lower clamps, respectively. The salt spray environment chamber is installed on one side of the testing frame through an adjustable support component. The salt spray generating device, the exhaust gas purification device, and the waste liquid collection device are respectively connected to the salt spray environment chamber. The control and data acquisition system is electrically connected to the fatigue testing machine and the salt spray environment chamber, respectively. The control and data acquisition system includes: The data acquisition module is used to simultaneously acquire the mechanical response parameters of the load detection component, the environmental status information output by the temperature and humidity sensor, the working status information of the salt spray generator and the compressed air supply system, and the emission collection status information of the exhaust gas purification device and the waste liquid collection device during the loading process of the anchor bolt sample, and generate a corrosion mechanics data sequence. The terminal control module is used to generate mechanical loading commands and environmental spray commands according to the preset test plan, apply constant load, cyclic load or pulsed disturbance load to the anchor bolt sample, and generate a stop command and save the corresponding test data when the anchor bolt sample reaches the specified number of cycles, produces obvious deformation or breaks. The analysis and evaluation module is used to extract corrosion mechanics coupling characteristics based on corrosion mechanics data sequences, evaluate the degree of corrosion fatigue damage of anchor bolt samples, generate remaining life prediction results and performance degradation early warning information based on the evaluation results, and update the preset test plan. The specific process for assessing the degree of corrosion fatigue damage of anchor bolt specimens includes: Based on the corrosion mechanics data sequence and experimental data, the corrosion mechanics coupling characteristics of the anchor bolt samples are extracted. Based on the corrosion mechanics coupling characteristics, the increments of corrosion damage variables and mechanical damage variables are determined, and the accelerating factor of corrosion on mechanical damage and the promoting factor of mechanical load on corrosion damage are generated. The corrosion-fatigue coupled damage variable of the anchor bolt sample is calculated by accumulating the increments of corrosion damage variable, mechanical damage variable, acceleration factor, and promoting factor according to the cycle number increment. The calculation formula for the corrosion-fatigue coupled damage variable is as follows: in, For the first Corrosion fatigue coupled damage variables after each cycle number increment For the first Corrosion fatigue coupled damage variables after each cycle number increment; For the first The increment of mechanical damage variable corresponding to the increment of each cycle number; For the first The increment of corrosion damage variable corresponding to the increment of each cycle number; For the first Mechanical damage variable after each cycle increment; For the first Corrosion damage variable after each iteration increment; For the first The acceleration factor of corrosion on mechanical damage corresponding to each cycle increment; For the first The promoting factor of mechanical load on corrosion damage corresponding to the increment of each cycle number; For the first The environmental mechanics weighting coefficient corresponding to the increment of each cycle number; The corrosion fatigue coupled damage variable is compared with the preset stage threshold to determine the current test stage of the anchor bolt sample, and the corresponding remaining life prediction result and performance degradation early warning information are generated based on the judgment result.

[0007] Furthermore, the fatigue testing machine applies constant load, cyclic load, or pulsed disturbance load to the anchor bolt specimen installed between the upper and lower clamps according to the preset load size, loading frequency, and loading waveform. This is used to simulate the combined effects of various in-situ corrosion environmental factors on the anchor bolt during long-term service. The load detection component integrates load sensors and displacement sensors to acquire the test parameters of the anchor bolt specimen in real time, including load, displacement, number of cycles, and failure time.

[0008] Furthermore, the upper and lower surfaces of the salt spray environment chamber are respectively provided with through holes for anchor rod samples to pass through. An upper dynamic seal and a lower dynamic seal are respectively installed at the through holes. An observation window is provided on one side of the salt spray environment chamber. Salt spray nozzles and temperature and humidity sensors are installed inside the chamber. One side of the salt spray nozzle is connected to the salt spray generating device through a delivery pipeline.

[0009] Furthermore, the salt spray environment chamber is equipped with an exhaust port and a drain port. The salt spray gas in the salt spray environment chamber is discharged to the exhaust gas purification device through the exhaust port. A drain pipe is installed on one side of the drain port, and the drain pipe is connected to the waste liquid collection device on the other side. The condensate and sediment formed in the salt spray environment chamber enter the waste liquid collection device through the drain pipe.

[0010] Furthermore, one side of the salt spray generating device is connected to a compressed air supply system, which includes an air compressor, a filter and pressure regulating component, and an air supply pipeline, for providing the compressed air required for salt spray atomization. The compressed air enters the salt spray generating device after being filtered and pressure regulated.

[0011] Furthermore, the salt spray generating device includes a salt spray machine, a corrosion solution storage component, an atomizing component, and a salt spray delivery pipeline. The corrosion solution storage component stores a pre-prepared corrosion solution. The corrosion solution passes through the atomizing component and is formed into salt spray under the action of compressed air from the compressed air supply system. The salt spray is then delivered into the salt spray environment chamber through the salt spray delivery pipeline and sprayed through the salt spray nozzle.

[0012] Furthermore, the temperature and humidity sensor is used to detect the temperature, humidity and salt spray working status in the environmental chamber. The temperature and humidity sensor interacts with the control and data acquisition system. The control and data acquisition system controls the start and stop of the salt spray machine and the compressed air supply system according to the preset spray conditions. By adjusting the spray time, interval time, air supply pressure and ambient temperature, continuous spray or periodic spray conditions consistent with the preset spray conditions are generated.

[0013] Furthermore, the updated preset test plan specifically includes: Based on the comparison results between the corrosion fatigue coupled damage variable and the first preset threshold and the second preset threshold, the current test stage of the anchor bolt sample is determined, wherein the first preset threshold is less than the second preset threshold. When the corrosion fatigue coupled damage variable is less than the first preset threshold, it is determined to be in the initial degradation stage. The current load amplitude, loading frequency and salt spray concentration are maintained, and the spraying time is increased by the first preset increment. When the corrosion fatigue coupled damage variable is between the first preset threshold and the second preset threshold, it is determined to be in the accelerated degradation stage. The load amplitude is reduced by the second preset increment, and the salt spray concentration is increased by the third preset increment. At the same time, the sampling frequency of the data acquisition module is increased. When the corrosion fatigue coupled damage variable exceeds the second preset threshold, it is determined to be in an unstable stage, a shutdown command is generated, and the current corrosion fatigue coupled damage variable, cycle number, remaining life prediction result and performance degradation early warning information are associated and saved. The adjusted parameters are used as the updated preset test scheme. The terminal control module generates updated mechanical loading instructions and environmental spray instructions based on the updated preset test scheme.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention places a salt spray environment chamber between the upper and lower clamps of a fatigue testing machine, allowing the middle test section of the anchor bolt to simultaneously bear axial loads in a salt spray corrosion environment. This avoids the separation of corrosion testing and mechanical testing. The fatigue testing machine can apply constant loads, cyclic loads, or pulsed disturbance loads to simulate stress states such as long-term support, equipment vibration, and mining disturbances. It can also be extended to simulate complex service conditions such as tension and torsion, providing in-situ testing conditions for assessing the corrosion rate, bearing capacity, and lifespan of anchor bolts in deep, high-stress, and high-mineralization mine water environments.

[0015] 2. The salt spray environment chamber of this invention is installed through adjustable support components and does not bear the axial test load of the anchor bolt, thus avoiding the influence of the chamber's own weight and pipeline forces on load and displacement measurements. The upper and lower dynamic seals reduce salt spray leakage while allowing the anchor bolt to move back and forth axially. The salt spray generation system and compressed air supply system can adjust the salt concentration, pH value, air supply pressure, spray time, interval time, and ambient temperature and humidity to simulate complex corrosive environments such as neutral, acidic, high temperature and high humidity, and water erosion, thereby accelerating the corrosion of the anchor bolt and shortening the indoor test cycle.

[0016] 3. The control and data acquisition system of this invention synchronously records parameters such as load, displacement, loading frequency, number of cycles, fracture time, corrosion time, and ambient temperature and humidity, and establishes the correspondence between corrosion conditions, disturbance load and anchor bolt life. It is used to evaluate the anchor bolt corrosion rate, damage evolution, remaining life and failure time. The exhaust gas purification device and waste liquid collection device centrally treat salt spray gas, condensate and sediment, reducing the corrosion of salt spray and corrosive liquid on the testing machine, fixtures, sensors and surrounding equipment, and ensuring the safety, stability and repeatability of the test. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the in-situ corrosion environment anchor performance testing device of the present invention; Figure 2 This is a schematic diagram of the control and data acquisition system module of the present invention; Figure 3 This is a schematic diagram of the process for evaluating the degree of corrosion fatigue damage of anchor bolt samples according to the present invention.

[0018] In the diagram, 1. Test frame; 2. Servo actuator; 3. Upper clamp; 4. Load detection assembly; 5. Anchor bolt sample; 6. Salt spray environment chamber; 7. Upper dynamic seal; 8. Lower dynamic seal; 9. Adjustable support component; 10. Observation window; 11. Salt spray nozzle; 12. Temperature and humidity sensor; 13. Drainage pipeline; 14. Lower clamp; 15. Air compressor; 16. Filter and pressure regulating assembly; 17. Salt spray generator; 18. Control and data acquisition system; 19. Exhaust gas purification device; 20. Waste liquid collection device. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1-3 The present invention provides the following technical solutions: A corrosion-mechanical coupled in-situ loading anchor performance testing system includes a fatigue testing machine, an anchor sample 5, a salt spray environment chamber 6, a salt spray generating device 17, a control and data acquisition system 18, an exhaust gas purification device 19, and a waste liquid collection device 20. The fatigue testing machine includes a testing frame 1, a servo actuator 2, an upper clamp 3, a lower clamp 14, and a load detection component 4. The fatigue testing machine applies constant load, cyclic load, or pulsed disturbance load to the anchor bolt sample 5 installed between the upper clamp 3 and the lower clamp 14 according to the preset load size, loading frequency, and loading waveform. This is used to simulate the combined effects of groundwater erosion, changes in ambient temperature and humidity, and stress disturbance of surrounding rock on the anchor bolt during long-term service. The load detection component 4 integrates a load sensor and a displacement sensor to acquire the test parameters of the anchor bolt sample 5 in real time, including load, displacement, number of cycles and failure time. The salt spray environment chamber 6 is set between the upper clamp 3 and the lower clamp 14. The two ends of the anchor rod sample 5 pass through the salt spray environment chamber 6 and are connected to the upper clamp 3 and the lower clamp 14 respectively. The axial load is applied by the servo actuator 2. The salt spray environment chamber 6 is installed on one side of the test frame 1 through the adjustable support component 9 so that the salt spray environment chamber 6 itself does not bear the axial test load of the anchor rod sample 5. The upper and lower surfaces of the salt spray environment chamber 6 are respectively provided with through holes for the anchor rod sample 5 to pass through. The upper dynamic seal 7 and the lower dynamic seal 8 are respectively installed at the through holes to allow the anchor rod sample 5 to generate axial displacement while reducing the leakage of salt spray from the exit point. The salt spray environment chamber 6 has an openable observation window 10 on one side, which facilitates the installation of anchor bolt samples 5, adjustment of salt spray nozzles 11, and observation of the surface condition of anchor bolt samples 5. Salt spray nozzles 11 and temperature and humidity sensors 12 are installed in the chamber. One side of the salt spray nozzles 11 is connected to the salt spray generating device 17 through a delivery pipeline. The temperature and humidity sensors 12 are used to detect the temperature, humidity and salt spray working status in the environment chamber. The temperature and humidity sensors 12 interact with the control and data acquisition system 18. The salt spray generator 17, the exhaust gas purification device 19 and the waste liquid collection device 20 are respectively connected to the salt spray environment chamber 6. The control and data acquisition system 18 is electrically connected to the fatigue testing machine and the salt spray environment chamber 6 respectively. One side of the salt spray generator 17 is connected to the compressed air supply system. The compressed air supply system includes an air compressor 15, a filter and pressure regulating component 16, and an air supply pipeline, which is used to provide the compressed air required for salt spray atomization. After being filtered and pressure regulated, the compressed air enters the salt spray generator 17. By adjusting the air supply pressure and air supply flow, the degree of salt spray atomization and the amount of spray can be controlled, so that the salt spray environment chamber 6 maintains relatively stable salt spray settling conditions.

[0021] In this embodiment, a constant load, cyclic load, or pulsed disturbance load is applied to the anchor bolt sample 5 in an in-situ salt spray corrosion environment by a fatigue testing machine and a salt spray environment chamber 6. This realistically simulates the corrosion-stress coupling effect of the anchor bolt under long-term support, equipment vibration, and mining disturbance conditions. The load detection component 4 is used to acquire parameters such as load, displacement, number of cycles, and failure time in real time. Furthermore, the salt spray environment chamber does not bear the axial test load of the anchor bolt. With the help of upper and lower dynamic seals, the axial displacement of the sample is allowed while reducing salt spray leakage, thereby ensuring loading accuracy and corrosion environment stability. The control and data acquisition system realizes the linkage between environmental parameter monitoring and the test process, making the test closer to engineering reality and improving the reliability of test data, automation, and test efficiency.

[0022] In this embodiment, the salt spray environment chamber 6 is equipped with an exhaust port and a drain port. The salt spray gas in the salt spray environment chamber 6 is discharged to the exhaust gas purification device 19 through the exhaust port. After being demisted or neutralized by the exhaust gas purification device 19, it is discharged. A drain pipe 13 is installed on one side of the drain port. One side of the drain pipe 13 is connected to the waste liquid collection device 20. The condensate and sediment formed in the salt spray environment chamber 6 enter the waste liquid collection device 20 through the drain pipe 13 to prevent the salt spray and corrosive liquid from corroding the fatigue testing machine and surrounding equipment. This allows the salt spray to act evenly on the anchor test section and collects the sedimented salt spray and condensate in a concentrated manner.

[0023] In this embodiment, the salt spray generating device 17 includes a salt spray machine, a corrosion solution storage component, an atomizing component, and a salt spray delivery pipeline. The corrosion solution storage component stores a pre-prepared corrosion solution. The corrosion solution passes through the atomizing component (nozzle), and compressed air flows through the nozzle at high speed, forming a low-pressure zone near the suction port, allowing the corrosion solution to enter the nozzle. Subsequently, the salt solution is broken into fine droplets under the shearing action of the high-speed airflow, dispersed by the spray tower, and enters the test chamber. It is then sent to the salt spray environment chamber 6 by the salt spray delivery pipeline and sprayed through the salt spray nozzle 11. According to the test requirements, the salt concentration, pH, spray volume, and spray cycle of the corrosion solution can be adjusted to simulate neutral, acidic, or other complex corrosion environments. The position and direction of the salt spray nozzle 11 can be adjusted to ensure that the anchor test section is in a stable and uniform salt spray environment.

[0024] In this embodiment, the control and data acquisition system 18 controls the start and stop of the salt spray machine and the compressed air supply system according to preset spray conditions. By adjusting the spray time, intermittent time, air supply pressure, and ambient temperature, it generates continuous spray or periodic spray conditions consistent with the preset spray conditions. The concentration and pH value of the corrosive solution are prepared and measured before the test begins. During the test, the corrosive solution is replenished or replaced as needed to maintain stable test conditions, including: The data acquisition module is used to simultaneously acquire the mechanical response parameters of the load detection component 4 during the loading process of the anchor bolt sample 5, including load signal, displacement signal, number of cycles and failure time, environmental status information output by the temperature and humidity sensor 12, such as temperature signal, humidity signal and salt spray working status signal, working status information of the salt spray generator 17 and compressed air supply system, and emission collection status information of the exhaust gas purification device 19 and waste liquid collection device 20, and generate a corrosion mechanics data sequence. The terminal control module is used to generate mechanical loading commands and environmental spray commands according to the preset test plan, apply constant load, cyclic load or pulsed disturbance load to the anchor bolt sample 5, and generate a stop command and save the corresponding test data when the anchor bolt sample 5 reaches the specified number of cycles, produces obvious deformation or breaks. The analysis and evaluation module is used to extract corrosion mechanics coupling characteristics based on the corrosion mechanics data sequence, evaluate the degree of corrosion fatigue damage of anchor bolt sample 5, generate remaining life prediction results and performance degradation early warning information based on the evaluation results, and update the preset test plan.

[0025] In this embodiment, the specific process for evaluating the degree of corrosion fatigue damage of anchor bolt sample 5 includes: Based on the corrosion mechanics data sequence and experimental data, the corrosion mechanics coupling characteristics of anchor bolt sample 5 were extracted, including actual axial test load, displacement amplitude, number of cycles, stiffness degradation, hysteresis energy consumption, salt spray deposition, salt spray deposition uniformity, condensate discharge, salt concentration of corrosion solution, pH value of corrosion solution, temperature, humidity, spraying time and interval time. Based on the coupling characteristics of corrosion mechanics, the following parameters were extracted to determine the increment of corrosion damage variables: salt spray deposition rate, salt spray deposition uniformity, condensate discharge rate, salt concentration of the corrosive solution, pH value of the corrosive solution, temperature, humidity, spraying time, and interval time. in, To establish a predefined mapping relationship for corrosion damage increments; This indicates the amount of salt spray deposition. Indicates the pH of the corrosive solution. Indicates temperature. Indicates humidity. Indicates spraying time. Indicates the interval time. All values ​​were determined based on the coupling characteristics of corrosion mechanics and were normalized. For the first The increment of the number of iterations; Based on the actual axial test load, displacement amplitude, number of cycles, stiffness degradation, and hysteresis energy consumption, the increment of mechanical damage variables is generated: in, Preset mechanical damage increment mapping relationship; This represents the stress amplitude of the actual axial test load. Indicates the loading frequency. Indicates the increment of displacement amplitude. This indicates the amount of stiffness degradation. Indicates hysteresis energy consumption. All values ​​were determined based on the coupling characteristics of corrosion mechanics and were normalized. Based on the actual axial test load, salt spray deposition, and the increment of corrosion damage variables, an acceleration factor for corrosion on mechanical damage is generated: in, The preset acceleration factor coefficient; The corrosion damage variable is updated based on its increment, and a factor promoting corrosion damage under mechanical load is generated based on the actual axial test load, displacement amplitude, and corrosion damage variable. in, For the first Corrosion damage variable after each iteration increment ; The preset promoting factor coefficient; For reference load amplitude;

[0026] Based on the increments of corrosion damage variable, mechanical damage variable, acceleration factor, and promoting factor, and accumulated according to the increment of cycle number, the corrosion fatigue coupled damage variable of anchor bolt sample 5 is calculated. The calculation formula for the corrosion fatigue coupled damage variable is as follows: in, For the first Corrosion fatigue coupled damage variables after each cycle number increment For the first Corrosion fatigue coupled damage variables after each cycle number increment; For the first The increment of mechanical damage variable corresponding to the increment of each cycle number; For the first The increment of corrosion damage variable corresponding to the increment of each cycle number; For the first Mechanical damage variable after each cycle increment; For the first Corrosion damage variable after each iteration increment; For the first The acceleration factor of corrosion on mechanical damage corresponding to each cycle increment; For the first The promoting factor of mechanical load on corrosion damage corresponding to the increment of each cycle number; For the first The environmental mechanics weighting coefficient corresponding to the increment of each cycle number; in, It is the apparent activation energy; It is the gas constant; For reference loading frequency; , , , Preset weighting coefficients; The index is the increment of the loop count, and it is a positive integer. The corrosion fatigue coupled damage variable is compared with the preset stage threshold to determine the current test stage of anchor bolt sample 5, including the initial degradation stage, accelerated degradation stage or instability stage, and the corresponding remaining life prediction result and performance degradation early warning information are generated based on the judgment result.

[0027] In this embodiment, updating the preset test plan specifically includes: Based on the comparison results between the corrosion fatigue coupled damage variable and the first preset threshold and the second preset threshold, the current test stage of the anchor bolt sample 5 is determined, wherein the first preset threshold is less than the second preset threshold. When the corrosion fatigue coupled damage variable is less than the first preset threshold, it is determined to be in the initial degradation stage. The current load amplitude, loading frequency and salt spray concentration are maintained, and the spraying time is increased by the first preset increment. When the corrosion fatigue coupled damage variable is between the first preset threshold and the second preset threshold, it is determined to be in the accelerated degradation stage. The load amplitude is reduced by the second preset increment, and the salt spray concentration is increased by the third preset increment. At the same time, the sampling frequency of the data acquisition module is increased. When the corrosion fatigue coupled damage variable exceeds the second preset threshold, it is determined to be in an unstable stage, a shutdown command is generated, and the current corrosion fatigue coupled damage variable, cycle number, remaining life prediction result and performance degradation early warning information are associated and saved. The adjusted parameters, including salt spray concentration, pH value of corrosive solution, spray time, interval time, ambient temperature, ambient humidity, load amplitude, loading frequency, upper limit of cycle number and test termination conditions, are used as the updated preset test scheme. The terminal control module generates updated mechanical loading instructions and environmental spray instructions based on the updated preset test scheme.

[0028] In the above embodiments, the control and data acquisition system 18 controls each terminal to achieve continuous or periodic spraying, and maintains stable test conditions such as corrosion solution concentration, pH value, spraying time, intermittent time, gas supply pressure, and ambient temperature. At the same time, it generates a complete corrosion mechanics data sequence, extracts corrosion mechanics coupling characteristics, calculates corrosion fatigue coupling damage variables, and realizes the discrimination of initial degradation, accelerated degradation, and instability stages. Then, it generates remaining life prediction results and performance degradation early warning information. Simultaneously, it dynamically adjusts parameters and updates the preset test plan according to the damage stage, so that the test process can truly reflect the damage evolution of the anchor bolt under the coupled action of corrosion force, improve the automation, adaptability, and data integrity of the test, enhance the accuracy of remaining life prediction and early warning, and ensure the safety, stability, and repeatability of the test.

[0029] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A corrosion-mechanical coupled in-situ loading anchor performance testing system, comprising a fatigue testing machine, an anchor specimen (5), a salt spray environment chamber (6), a salt spray generating device (17), a control and data acquisition system (18), an exhaust gas purification device (19), and a waste liquid collection device (20), characterized in that, The fatigue testing machine includes a testing frame (1), a servo actuator (2), an upper clamp (3), a lower clamp (14), and a load detection component (4). The salt spray environment chamber (6) is set between the upper clamp (3) and the lower clamp (14). The two ends of the anchor rod sample (5) pass through the salt spray environment chamber (6) and are connected to the upper clamp (3) and the lower clamp (14) respectively. The salt spray environment chamber (6) is installed on one side of the testing frame (1) through an adjustable support component (9). The salt spray generating device (17), the exhaust gas purification device (19), and the waste liquid collection device (20) are connected to the salt spray environment chamber (6) respectively. The control and data acquisition system (18) is electrically connected to the fatigue testing machine and the salt spray environment chamber (6) respectively. The control and data acquisition system (18) includes: The data acquisition module is used to simultaneously acquire the mechanical response parameters of the load detection component (4), the environmental status information output by the temperature and humidity sensor (12), the working status information of the salt spray generator (17) and the compressed air supply system, and the emission collection status information of the exhaust gas purification device (19) and the waste liquid collection device (20) during the loading process of the anchor bolt sample (5), and generate a corrosion mechanics data sequence. The terminal control module is used to generate mechanical loading instructions and environmental spray instructions according to the preset test plan, apply constant load, cyclic load or pulse disturbance load to the anchor bolt sample (5), and generate a stop instruction and save the corresponding test data when the anchor bolt sample (5) reaches the specified number of cycles, produces obvious deformation or breaks. The analysis and evaluation module is used to extract corrosion mechanics coupling characteristics based on the corrosion mechanics data sequence, evaluate the degree of corrosion fatigue damage of the anchor bolt sample (5), generate the remaining life prediction result and performance degradation early warning information based on the evaluation result, and update the preset test plan. The specific process for evaluating the degree of corrosion fatigue damage of the anchor bolt specimen (5) includes: Based on the corrosion mechanics data sequence and experimental data, the corrosion mechanics coupling characteristics of the anchor bolt sample (5) were extracted; Based on the coupling characteristics of corrosion mechanics, the increments of corrosion damage variables and mechanical damage variables are determined, and the accelerating factor of corrosion on mechanical damage and the promoting factor of mechanical load on corrosion damage are generated. Based on the increments of corrosion damage variable, mechanical damage variable, acceleration factor, and promoting factor, and accumulated according to the increment of cycle number, the corrosion fatigue coupled damage variable of anchor bolt sample (5) is calculated. The calculation formula for the corrosion fatigue coupled damage variable is as follows: in, For the first Corrosion fatigue coupled damage variables after each cycle number increment For the first Corrosion fatigue coupled damage variables after each cycle number increment; For the first The increment of mechanical damage variable corresponding to the increment of each cycle number; For the first The increment of corrosion damage variable corresponding to the increment of each cycle number; For the first Mechanical damage variable after each cycle increment; For the first Corrosion damage variable after each iteration increment; For the first The acceleration factor of corrosion on mechanical damage corresponding to each cycle increment; For the first The promoting factor of mechanical load on corrosion damage corresponding to the increment of each cycle number; For the first The environmental mechanics weighting coefficient corresponding to the increment of each cycle number; The corrosion fatigue coupled damage variable is compared with the preset stage threshold to determine the current test stage of the anchor bolt sample (5), and the corresponding remaining life prediction result and performance degradation warning information are generated based on the judgment result.

2. The anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading as described in claim 1, characterized in that, The fatigue testing machine applies constant load, cyclic load or pulsed disturbance load to the anchor rod specimen (5) installed between the upper clamp (3) and the lower clamp (14) according to the preset load size, loading frequency and loading waveform, in order to simulate the combined effect of various in-situ corrosion environmental factors on the anchor rod during long-term service; the load detection component (4) integrates load sensor and displacement sensor to obtain the test parameters of the anchor rod specimen (5) in real time, including load, displacement, number of cycles and failure time.

3. The anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading as described in claim 1, characterized in that, The salt spray environment chamber (6) has through holes on its upper and lower surfaces for the anchor rod sample (5) to pass through. An upper dynamic seal (7) and a lower dynamic seal (8) are installed at the through holes. An observation window (10) is provided on one side of the salt spray environment chamber (6). A salt spray nozzle (11) and a temperature and humidity sensor (12) are installed inside the chamber. The salt spray nozzle (11) is connected to the salt spray generating device (17) through a delivery pipeline.

4. The anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading as described in claim 3, characterized in that, The salt spray environment chamber (6) is equipped with an exhaust port and a drain port. The salt spray gas in the salt spray environment chamber (6) is discharged to the exhaust gas purification device (19) through the exhaust port. A drain pipe (13) is installed on one side of the drain port. The drain pipe (13) is connected to the waste liquid collection device (20) on one side. The condensate and sediment formed in the salt spray environment chamber (6) enter the waste liquid collection device (20) through the drain pipe (13).

5. The anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading as described in claim 3, characterized in that, The salt spray generator (17) is connected to a compressed air supply system on one side. The compressed air supply system includes an air compressor (15), a filter and pressure regulating component (16), and an air supply pipeline, which is used to provide the compressed air required for salt spray atomization. The compressed air enters the salt spray generator (17) after being filtered and pressure regulated.

6. The anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading as described in claim 5, characterized in that, The salt spray generating device (17) includes a salt spray machine, a corrosion solution storage component, an atomizing component, and a salt spray delivery pipeline. The corrosion solution storage component stores a pre-prepared corrosion solution. The corrosion solution passes through the atomizing component, and compressed air flows at high speed through the nozzle, forming a low-pressure zone near the liquid inlet, allowing the corrosion solution to enter the nozzle. Subsequently, the salt solution is broken into fine droplets under the shearing action of the high-speed airflow, dispersed by the spray tower, and enters the test chamber. It is then sent to the salt spray environment chamber (6) through the salt spray delivery pipeline and sprayed through the salt spray nozzle (11).

7. The anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading as described in claim 6, characterized in that, The temperature and humidity sensor (12) is used to detect the temperature, humidity and working status of the salt spray environment chamber (6). The temperature and humidity sensor (12) interacts with the control and data acquisition system (18). The control and data acquisition system (18) controls the start and stop of the salt spray machine and the compressed air supply system according to the preset spray conditions. By adjusting the spray time, intermittent time, air supply pressure and ambient temperature, continuous spray or periodic spray conditions consistent with the preset spray conditions are generated.

8. The anchor bolt performance testing system with corrosion-mechanical coupling in-situ loading as described in claim 1, characterized in that, The updated preset test plan specifically includes: Based on the comparison results between the corrosion fatigue coupled damage variable and the first preset threshold and the second preset threshold, the current test stage of the anchor bolt sample (5) is determined, wherein the first preset threshold is less than the second preset threshold; When the corrosion fatigue coupled damage variable is less than the first preset threshold, it is determined to be in the initial degradation stage. The current load amplitude, loading frequency and salt spray concentration are maintained, and the spraying time is increased by the first preset increment. When the corrosion fatigue coupled damage variable is between the first preset threshold and the second preset threshold, it is determined to be in the accelerated degradation stage. The load amplitude is reduced by the second preset increment, and the salt spray concentration is increased by the third preset increment. At the same time, the sampling frequency of the data acquisition module is increased. When the corrosion fatigue coupled damage variable exceeds the second preset threshold, it is determined to be in an unstable stage, a shutdown command is generated, and the current corrosion fatigue coupled damage variable, cycle number, remaining life prediction result and performance degradation early warning information are associated and saved. The adjusted parameters are used as the updated preset test scheme. The terminal control module generates updated mechanical loading instructions and environmental spray instructions based on the updated preset test scheme.

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