Environment-load coupling test device for adaptive compensation type prestressed concrete beam

Abstract

This application relates to the field of durability testing technology for concrete components, specifically disclosing an adaptive compensation-type environmental-load coupling testing device for prestressed concrete beams. The device includes an adjustable guide rail frame, an environmental erosion simulation module, a continuous load application module, a prestress state monitoring module, and an adaptive control module. The environmental erosion simulation module sprays an erosive medium onto the prestressed concrete beam; the continuous load application module applies a continuous load to the prestressed concrete beam; the prestress state monitoring module anchors the prestressed concrete beam and monitors its prestress in real time; and the adaptive control module controls the loading state of the continuous load application module based on changes in the prestress of the prestressed concrete beam to compensate for prestress loss caused by environmental erosion. This application maintains a stable stress state under long-term erosion-load coupling, improving the accuracy of the test.

Description

Technical Field

[0001] This application relates to the field of concrete component durability testing technology, and in particular to an adaptive compensation type environmental-load coupling test device for prestressed concrete beams. Background Technology

[0002] Concrete structures, due to their excellent mechanical properties and economy, are widely used in railway engineering. Prestressed concrete beams, as core load-bearing components, are critical infrastructure ensuring the safe and stable operation of railway lines. However, during service, prestressed concrete beams are continuously subjected to erosion from the atmosphere, rainwater, marine salt spray, saline-alkali land, and the coupled effects of special loads such as train operation loads and seismic forces. This makes them prone to defects such as concrete cracking, corrosion and cumulative damage to reinforcing bars and steel strands, seriously affecting the safety and reliability of in-service railway bridges. Therefore, conducting tests on prestressed concrete beams under the coupled effects of environmental erosion and continuous loads is of great engineering value and significance in order to effectively evaluate the safety and durability of prestressed concrete beams under complex service conditions.

[0003] Currently, experimental research on concrete structures largely focuses on single environmental erosion or single load scenarios. Existing experimental devices struggle to achieve precise coupled simulation of environmental erosion and continuous load. Some devices can only conduct sequential tests of corrosion followed by loading or loading followed by corrosion, failing to reproduce the real-world conditions of simultaneous action under actual service conditions. A few coupled experimental devices often suffer from problems such as singular environmental simulation and low load control precision. Furthermore, during long-term coupled testing, as materials deteriorate due to environmental erosion (e.g., steel strand corrosion, concrete creep), irreversible and severe losses of prestress within the beam occur, causing the actual stress state of the specimen to deviate from the preset target, making it difficult for the test results to reflect the structural response under true stress levels. In addition, existing devices generally lack the ability to monitor and coordinate the dynamic evolution characteristics of beam cracks, deformation, and corrosion processes in real time, making it difficult to accurately capture the damage evolution patterns of structures and materials under coupled effects.

[0004] With the increasing demands for structural durability in railway engineering, there is an urgent need for a testing device capable of accurately simulating the coupled effects of environmental erosion and continuous load. Through an adaptive dynamic collaborative loading system, the actual service conditions of railway prestressed concrete beams under different environments can be reproduced. The system will systematically study the structural damage mechanism and performance degradation law under the coupled effects of environment and load, providing reliable experimental data support for the durability design, life prediction, and operation and maintenance decisions of railway prestressed concrete beams. This will compensate for the shortcomings of existing testing devices in coupling simulation capabilities and meet the needs of engineering practice for precise testing technology. Summary of the Invention

[0005] To improve the above-mentioned technical problems, this application provides an adaptive compensation prestressed concrete beam environmental-load coupling test device.

[0006] This application provides an adaptive compensation-type prestressed concrete beam environmental-load coupling test device, which adopts the following technical solution: An adaptive compensation-type environmental-load coupling test device for prestressed concrete beams includes: Adjustable guide rail frame; An environmental erosion simulation module is fixedly mounted on the adjustable guide rail frame and is used to spray an erosive medium onto the prestressed concrete beam. A continuous load application module is used to apply a continuous load to a prestressed concrete beam; the continuous load application module is synchronously slidably mounted on the adjustable guide rail frame with the prestressed concrete beam to adjust the erosion position of the prestressed concrete beam. The prestressing state monitoring module is used to anchor the prestressed concrete beam and monitor the prestress of the prestressed concrete beam in real time. An adaptive control module is used to control the loading state of the continuous load application module according to the changes in the prestress of the prestressed concrete beam, so as to compensate for the prestress loss of the prestressed concrete beam caused by environmental erosion.

[0007] This application sets up an adjustable guide rail frame, fixes the environmental erosion simulation module on the frame, and slides the continuous load application module and the prestressed concrete beam on the guide rail, realizing the dynamic adjustment of the spray position of the eroding medium and the load application position, which can flexibly simulate the local erosion and load coupling conditions in different sections.

[0008] The adaptive control module dynamically controls the continuous load application module to compensate for the prestress loss based on the real-time feedback from the prestress state monitoring module. This improves the problem that the actual stress state of the beam deviates from the preset target due to material deterioration (such as steel strand corrosion and concrete creep) in long-term coupled tests of traditional test devices. It ensures that the specimen maintains a stable equivalent stress state throughout the long-term test, which is beneficial to improving the accuracy and reliability of the coupled test.

[0009] Furthermore, the continuous load application module is provided in two sets, which are respectively set at both ends of the prestressed concrete beam. Each set of the continuous load application module includes a load application unit, a load monitoring unit, a hydraulic execution unit and an elastic compensation unit. The load application mechanism is used to apply load to the prestressed concrete beam, the load monitoring unit is used to monitor load fluctuations during the loading process, the hydraulic actuator is used to drive the load application mechanism to apply a compensating load to the prestressed concrete beam when the prestress loss is greater than a preset value, and the elastic compensation mechanism is used to drive the load application mechanism to apply a flexible compensating load to the prestressed concrete beam when the load fluctuation is greater than a preset value.

[0010] Furthermore, the load application unit includes a horizontally arranged upper loading bottom beam and a lower loading bottom beam, and also includes two threaded rods that vertically penetrate the upper loading bottom beam and the lower loading bottom beam. The lower loading bottom beam is fixedly mounted on the threaded rods, and the upper loading bottom beam is slidably mounted on the threaded rods. Two parallel prestressed concrete beams are arranged between the upper loading bottom beam and the lower loading bottom beam, and two supports are provided between the two prestressed concrete beams. The load monitoring unit includes a pressure sensor installed between the upper loading bottom beam and the prestressed concrete beam.

[0011] Furthermore, the hydraulic actuator includes a loading top beam and a pressure beam parallel to the upper loading bottom beam, the threaded rod passing through the loading top beam and the pressure beam, the loading top beam being fixedly mounted on the threaded rod, and the pressure beam being slidably mounted on the threaded rod; the hydraulic actuator also includes a hydraulic cylinder, the two ends of which are respectively fixedly connected to the loading top beam and the pressure beam; the elastic compensation unit is disposed between the pressure beam and the upper loading bottom beam.

[0012] Furthermore, the elastic compensation unit includes multiple sets of disc springs and multiple hydraulic rods arranged symmetrically.

[0013] A tiered compensation mechanism is established by combining a hydraulic actuator and an elastic compensation unit: when the prestress loss exceeds a first preset value, the hydraulic actuator initiates a significant active load compensation to restore the prestress level of the beam; when the load monitoring unit detects an instantaneous fluctuation exceeding a second preset value, the elastic compensation unit absorbs and compensates for small load fluctuations through the slight extension and retraction of the hydraulic rod and the flexible deformation of the disc spring. This dual adjustment mechanism, combining active hydraulic compensation and flexible elastic compensation, not only improves the prestress attenuation problem in long-term testing but also suppresses instantaneous disturbances during loading, enhancing the long-term stability and control accuracy of continuous loads.

[0014] Furthermore, the prestressed state monitoring module includes anchorages anchored to both ends of the steel strands of the prestressed concrete beam, and also includes a vibrating wire sensor installed between the anchorages and the end anchor plate of the prestressed concrete beam.

[0015] Vibrating wire sensors can measure minute prestress losses caused by steel strand corrosion, loosening, or concrete creep.

[0016] Furthermore, the adjustable guide rail frame includes a guide rail and a slide block slidably disposed on the guide rail, and the continuous load application module is fixedly disposed on the slide block; it also includes a drive component for driving the slide block to slide along the guide rail.

[0017] Through the coordination of guide rails, sliding blocks, and drive components, the continuous load application module and the prestressed concrete beam were moved as a whole during the test. This design allows the erosion location of the beam to no longer be a fixed area, but to be dynamically adjusted according to the test requirements, so as to achieve different combinations of erosion locations and loading locations, thus expanding the simulation capabilities of coupled tests.

[0018] Furthermore, a lateral support mechanism is provided on the outside of the adjustable guide rail frame. The lateral support mechanism includes a steel bracket and an inclined support rod fixed to the steel bracket, and also includes a spring fixed to one side of the steel bracket. The spring abuts against the flange of the prestressed concrete beam in the horizontal direction.

[0019] In long-term high-load tests, prestressed concrete beams may exhibit lateral bending or instability tendencies. This application constructs a high-rigidity reaction frame using steel supports and diagonal bracing rods, with springs elastically abutting against the beam flanges. When the beam undergoes lateral deformation, the springs provide an elastic restoring force that increases linearly with the amount of deformation. This effectively limits the lateral displacement of the beam, ensuring the stability of the loading posture, while also preventing rigid constraints from interfering with the free deformation of the beam. Thus, stable constraints are achieved without affecting the actual mechanical response of the beam.

[0020] Furthermore, the environmental erosion simulation module includes a water tank, a spraying mechanism, and a water pump. The water tank has an open upper part and is located below the adjustable guide rail frame. The spraying mechanism includes several water pipes fixed to the adjustable guide rail frame and multiple spray heads spaced apart on the water pipes. The spray heads face the prestressed concrete beam. The water pump is used to input the erosion solution stored in the water tank into the water pipes.

[0021] By fixing the water pipes of the spraying mechanism to an adjustable guide rail frame, the spray heads always face the prestressed concrete beam as the slide moves, ensuring the uniformity and effectiveness of the spraying of the corrosive medium. The water tank is positioned below the adjustable guide rail frame, forming a closed solution circulation system, which conserves corrosive solution and reduces environmental pollution.

[0022] Furthermore, one end of the steel strand of the prestressed concrete beam is connected to the positive terminal of a constant current power supply, and the negative terminal of the constant current power supply is connected to a stainless steel mesh fixed on the prestressed concrete beam to accelerate the electrochemical corrosion of the steel strand.

[0023] By adjusting the current density, the corrosion process of steel strands can be actively controlled, shortening the test cycle.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. This application monitors prestress changes in real time through a prestress state monitoring module (vibrating wire sensor). When the prestress loss exceeds the set value, the adaptive control module immediately instructs the hydraulic actuator to start pressurization and compensate the beam for load. This closed-loop control mechanism ensures that the specimen always bears the set effective prestress throughout the entire long-term coupled test cycle, regardless of material degradation. This improves the problem of data failure caused by stress decay in traditional tests and makes the coupled test results truly reflect the structural response under the preset stress level. 2. This application adopts a dual adjustment mechanism combining hydraulic active compensation and elastic flexible compensation: for the systematic prestress attenuation caused by material deterioration, hydraulic cylinders are used for active jacking compensation to restore the prestress level of the beam; for the load fluctuation caused by environmental disturbances during loading, hydraulic rods are used in conjunction with elastic elements such as disc springs for flexible compensation, absorbing the fluctuation energy through small deformations, and accurately controlling the load fluctuation within ±1% of the target value. 3. Because this application can keep the prestress of the beam stable near the target value, the internal stress of the beam can remain constant during the process of the continuous load application module moving back and forth on the adjustable guide rail frame and dynamically adjusting the erosion position. Therefore, the two key variables of load size and loading position / erosion position can be controlled independently to accurately reproduce the real service scenario of different sections suffering non-uniform erosion under load. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 This is a front view of an embodiment of this application; Figure 3 This is a structural schematic diagram of the continuous load application module in the embodiments of this application; Figure 4 This is a structural schematic diagram of the prestressed concrete beam and anchorage in the embodiments of this application; Figure 5 This is a schematic diagram of the adjustable guide rail frame in an embodiment of this application; Figure 6 This is a schematic diagram of the lateral support mechanism in the embodiments of this application.

[0026] Reference numerals: 1. Continuous load application module; 10. Threaded rod; 11. Loading top beam; 12. Pressure beam; 13. Upper loading bottom beam; 14. Lower loading bottom beam; 15. Fixed steel clamp; 16. Hydraulic cylinder; 17. Hydraulic rod; 18. Disc spring; 19. Pressure sensor; 2. Environmental erosion simulation module; 21. Water tank; 22. Spraying mechanism; 221. Water pipe; 222. Snap-on support rod; 223. Fixed snap-on; 224. Spray head; 23. Water pump; 24. Constant current power supply; 25. Stainless steel mesh; 3. Prestressed state monitoring module; 31. Prestressed concrete beam; 32. Vibrating wire sensor; 33. Anchorage; 34. Support; 4. Adjustable guide rail frame; 41. Guide rail; 42. Connecting rod; 43. Slide; 44. Pulley; 45. Horizontal gear; 46. Magnetic induction limiter; 47. Steel bracket; 48. Diagonal support rod; 49. Spring; 5. Adaptive control module. Detailed Implementation

[0027] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail.

[0028] This application discloses an adaptive compensation-type environmental-load coupling test device for prestressed concrete beams. (Refer to...) Figure 1 The adaptive compensation prestressed concrete beam environment-load coupling test device includes an adjustable guide rail frame 4, an environmental erosion simulation module 2, a continuous load application module 1, a prestress state monitoring module 3, and an adaptive control module 5.

[0029] The environmental erosion simulation module 2 sprays an erosive medium onto the prestressed concrete beam 31. This erosive medium is typically a erosive solution of a specific type and concentration prepared according to the simulated environment. The continuous load application module 1 applies a continuous load to the prestressed concrete beam 31. This module is synchronously slidably mounted on the adjustable guide rail frame 4 with the prestressed concrete beam 31 to adjust the erosion-affected position of the beam. This allows for dynamic adjustment of the erosive medium spraying position, enabling flexible simulation of localized erosion and load coupling conditions in different sections.

[0030] The prestress state monitoring module 3 is used to anchor the prestressed concrete beam 31 and monitor its prestress in real time. The adaptive control module 5 is used to control the loading state of the continuous load application module 1 according to the changes in prestress of the prestressed concrete beam 31, in order to compensate for the prestress loss caused by environmental erosion. This improves upon the problem in traditional testing devices where material deterioration (such as steel strand corrosion and concrete creep) causes the actual stress state of the beam to deviate from the preset target during long-term coupled tests. It ensures that the specimen maintains a stable equivalent stress state throughout the long-term test, which is beneficial for improving the accuracy and reliability of the coupled test.

[0031] Specifically, refer to Figure 1 Two sets of continuous load application modules 1 are provided, one at each end of the prestressed concrete beam 31. Each set of continuous load application modules 1 includes a load application unit, a load monitoring unit, a hydraulic actuator unit, and an elastic compensation unit. The load application mechanism applies load to the prestressed concrete beam 31, the load monitoring unit monitors load fluctuations during the loading process, the hydraulic actuator drives the load application mechanism to apply a compensating load to the prestressed concrete beam 31 when the prestress loss exceeds a preset value, and the elastic compensation mechanism drives the load application mechanism to apply a flexible compensating load to the prestressed concrete beam 31 when the load fluctuation exceeds a preset value.

[0032] Reference Figure 2 and Figure 3 The load application unit includes a horizontally arranged upper loading base beam 13 and a lower loading base beam 14, and two symmetrical threaded rods 10 that vertically penetrate the upper loading base beam 13 and the lower loading base beam 14. The lower loading base beam 14 is fixedly mounted on the threaded rods 10 by nuts, and the upper loading base beam 13 is slidably mounted on the threaded rods 10. (Refer to...) Figure 2 and Figure 4 Two parallel prestressed concrete beams 31 are arranged between the upper loading bottom beam 13 and the lower loading bottom beam 14, and two supports 34 are arranged between the two prestressed concrete beams 31.

[0033] Reference Figure 2 and Figure 3 The hydraulic actuator includes a loading top beam 11 and a pressure beam 12 parallel to the upper loading bottom beam 13. A threaded rod 10 passes through the loading top beam 11 and the pressure beam 12. The loading top beam 11 is fixedly mounted on the threaded rod 10 by a nut, and the pressure beam 12 is slidably mounted on the threaded rod 10. The hydraulic actuator also includes a hydraulic cylinder 16. One end of the hydraulic cylinder 16 is fixedly connected to the loading top beam 11 by a fixing steel clamp 15, and the other end of the hydraulic cylinder 16 is fixedly connected to the pressure beam 12.

[0034] Reference Figure 2 and Figure 3 The elastic compensation unit is located between the pressure beam 12 and the upper loading bottom beam 13, and includes two sets of disc springs 18 and two hydraulic rods 17 arranged symmetrically. The load monitoring unit includes a pressure sensor 19 located between the upper loading bottom beam 13 and the prestressed concrete beam 31.

[0035] Reference Figure 4The prestressed state monitoring module 3 includes anchorages 33 anchored to both ends of the steel strands of the prestressed concrete beam 31, and a vibrating wire sensor 32 installed between the anchorages 33 and the end anchor plates of the prestressed concrete beam 31. To accelerate the electrochemical corrosion of the steel strands, one end of the steel strands of the prestressed concrete beam 31 is connected to the positive terminal of a constant current power supply 24, and the negative terminal of the constant current power supply 24 is connected to a stainless steel mesh 25 fixed on the prestressed concrete beam 31.

[0036] A graded compensation mechanism is established by setting up a hydraulic actuator and an elastic compensation unit: when the prestress loss of the prestressed concrete beam 31 exceeds the preset value, the hydraulic actuator is activated to perform large-scale active load compensation to restore the prestress level of the beam; the load monitoring unit is used to monitor the continuous load level during the loading process and feeds the monitoring data back to the adaptive control module 5 in real time to realize a closed force control loop. When the load monitoring unit detects that the instantaneous fluctuation exceeds the preset value, the elastic compensation unit absorbs and compensates for the small load fluctuation through the slight extension and contraction of the hydraulic rod 17 and the flexible deformation of the disc spring 18. This dual adjustment mechanism combining hydraulic active compensation and elastic flexible compensation not only improves the prestress attenuation problem in long-term tests, but also suppresses instantaneous disturbances during the loading process, improving the long-term stability and control accuracy of continuous load.

[0037] Reference Figure 3 and Figure 5 The adjustable guide rail frame 4 includes a guide rail 41 and a slide block 43 slidably mounted on the guide rail 41. The threaded rod 10 and the lower loading beam 14 in the continuous load application module 1 are fixedly mounted on the slide block 43. There are two guide rails 41, and several connecting rods 42 are fixedly connected between the two parallel guide rails 41. Several pulleys 44 that cooperate with the guide rails 41 are rotatably mounted on the bottom of the slide block 43.

[0038] Reference Figure 5 The adjustable guide rail frame 4 also includes a drive assembly for driving the slide 43 to slide along the guide rail 41. Specifically, a side plate is fixedly provided on the outer side of the guide rail 41, and a horizontal gear 45 is rotatably provided on the inner side of the side plate. A spur rack that meshes with the horizontal gear 45 is provided on the outer side of the slide 43. The horizontal gear 45 is driven to rotate by a servo drive, thereby driving the slide 43 to slide along the guide rail 41. By controlling the rotation speed and start / stop of the horizontal gear 45, the moving speed and stroke of the slide 43 can be controlled, thereby realizing the overall movement of the continuous load application module 1 and the prestressed concrete beam 31 during the test. In order to limit the stroke of the slide 43, a magnetic induction limiter 46 is provided at the end of the guide rail 41.

[0039] Reference Figure 2 and Figure 6The adjustable guide rail frame 4 is equipped with a lateral support mechanism on its outer side. The lateral support mechanism includes a steel bracket 47 and an inclined support rod 48 fixed to the steel bracket 47, as well as a spring 49 fixed to one side of the steel bracket 47. The spring 49 abuts against the flange of the prestressed concrete beam 31 in the horizontal direction. The spring 49 provides an elastic restoring force that increases linearly with the amount of deformation, effectively limiting the lateral displacement of the beam and ensuring the stability of the loading posture.

[0040] Reference Figure 1 and Figure 2 The environmental erosion simulation module 2 includes a water tank 21, a spraying mechanism 22, and a water pump 23. The water tank 21 is open at the top and is located below the adjustable guide rail frame 4. The spraying mechanism 22 includes several water pipes 221 fixed to the adjustable guide rail frame 4 and multiple spray heads 224 spaced apart on the water pipes 221, with the spray heads 224 facing the prestressed concrete beam 31. The water pump 23 is used to input the erosion solution stored in the water tank 21 into the water pipes 221.

[0041] In this embodiment, refer to Figure 1 The water pipes 221 are arranged in two layers, corresponding to the positions of the two prestressed concrete beams 31 respectively. The two layers of water pipes 221 are connected by several snap-fit ​​struts 222. The lower layer of water pipes 221 is installed on the adjustable guide rail frame 4 by spaced-apart fixing clips 223. The layout of the water pipes 221 does not affect the movement of the prestressed concrete beams 31 and the continuous load application module 1 on the adjustable guide rail frame 4.

[0042] The adaptive control module 5 is connected to the vibrating wire sensor 32, pressure sensor 19, hydraulic cylinder 16, hydraulic rod 17 and constant current power supply 24 respectively to form a closed-loop control loop. It takes the prestress loss and continuous load change monitored in real time as multi-source inputs, and dynamically calculates and generates control commands through computer program. It dynamically adjusts the loading state of the continuous load application module 1 and the erosion condition of the environmental erosion simulation module 2, so as to achieve the dual synergy of mechanical compensation and environmental regulation during the environmental erosion process and maintain the stability of the equivalent stress state of the prestressed concrete beam 31.

[0043] As an example, during the experiment, as environmental erosion continues, the material of the prestressed concrete beam 31 deteriorates, causing changes in its internal stress state. When the vibrating wire sensor 32 detects that the prestress value has decreased by more than 5% compared to the initial target value, the adaptive control module 5 sends a command to the hydraulic cylinder 16 to initiate pressurization. The upper loading bottom beam 13 and the pressure beam 12 move down synchronously, and the pressure beam 12 compensates for the load on the prestressed concrete beam 31. At the same time, the pressure sensor 19 monitors the load fluctuations during the loading process in real time. When the load is detected to deviate from the set value by more than 3%, the adaptive control module 5 controls the hydraulic rod 17 to fine-tune the extension and retraction. The pressure beam 12 provides flexible load compensation for the prestressed concrete beam 31, ensuring that the continuous load borne by the prestressed concrete beam 31 recovers and remains within the error range of ±1% of the target value.

[0044] Through the above process, the adaptive control module 5 dynamically adjusts the loading conditions according to the monitored changes in the beam state, so that the specimen maintains a stable equivalent stress state throughout the long-term coupling test.

[0045] As a preferred embodiment, the adaptive control module 5 adjusts the start / stop or spray intensity of the water pump 23 and / or adjusts the acceleration current according to the changes in the damage state of the beam, so that the environmental erosion effect is adapted to the mechanical damage process.

[0046] As another preferred implementation, the adaptive control module 5 is connected to the image monitoring equipment via a data cable. The intelligent image recognition algorithm built into the adaptive control module 5 analyzes key indicators such as mid-span deflection, crack width, crack length and crack distribution density of the prestressed concrete beam 31 in real time, and integrates the visual recognition results as correction signals into the closed-loop control, forming an intelligent control system with multi-parameter coordination of mechanics, electricity and vision.

[0047] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An adaptive compensation-type environmental-load coupling test device for prestressed concrete beams, characterized in that: include: Adjustable guide rail frame; An environmental erosion simulation module is fixedly mounted on the adjustable guide rail frame and is used to spray an erosive medium onto the prestressed concrete beam. The continuous load application module is used to apply continuous loads to prestressed concrete beams; The continuous load application module is synchronously slidably mounted on the adjustable guide rail frame with the prestressed concrete beam to adjust the erosion position of the prestressed concrete beam. The prestressing state monitoring module is used to anchor the prestressed concrete beam and monitor the prestress of the prestressed concrete beam in real time. An adaptive control module is used to control the loading state of the continuous load application module according to the changes in the prestress of the prestressed concrete beam, so as to compensate for the prestress loss of the prestressed concrete beam caused by environmental erosion.

2. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 1, characterized in that: The continuous load application module is provided in two sets, which are respectively set at both ends of the prestressed concrete beam. Each set of the continuous load application module includes a load application unit, a load monitoring unit, a hydraulic execution unit and an elastic compensation unit. The load application mechanism is used to apply load to the prestressed concrete beam, the load monitoring unit is used to monitor load fluctuations during the loading process, the hydraulic actuator is used to drive the load application mechanism to apply a compensating load to the prestressed concrete beam when the prestress loss is greater than a preset value, and the elastic compensation mechanism is used to drive the load application mechanism to apply a flexible compensating load to the prestressed concrete beam when the load fluctuation is greater than a preset value.

3. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 2, characterized in that: The load application unit includes a horizontally arranged upper loading bottom beam and a lower loading bottom beam, and also includes two threaded rods that vertically penetrate the upper loading bottom beam and the lower loading bottom beam. The lower loading bottom beam is fixedly installed on the threaded rods, and the upper loading bottom beam is slidably installed on the threaded rods. Two parallel prestressed concrete beams are arranged between the upper loading bottom beam and the lower loading bottom beam, and two supports are provided between the two prestressed concrete beams. The load monitoring unit includes a pressure sensor installed between the upper loading bottom beam and the prestressed concrete beam.

4. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 3, characterized in that: The hydraulic actuator includes a loading top beam and a pressure beam parallel to the upper loading bottom beam. The threaded rod passes through the loading top beam and the pressure beam. The loading top beam is fixedly mounted on the threaded rod, and the pressure beam is slidably mounted on the threaded rod. The hydraulic actuator also includes a hydraulic cylinder, with both ends of the hydraulic cylinder fixedly connected to the loading top beam and the pressure beam, respectively. The elastic compensation unit is disposed between the pressure beam and the upper loading bottom beam.

5. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 4, characterized in that: The elastic compensation unit includes multiple sets of disc springs arranged symmetrically and multiple hydraulic rods.

6. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 1, characterized in that: The prestressed state monitoring module includes anchorages fixed to both ends of the steel strands of the prestressed concrete beam, and also includes a vibrating wire sensor installed between the anchorages and the end anchor plate of the prestressed concrete beam.

7. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 1, characterized in that: The adjustable guide rail frame includes a guide rail and a slide block slidably disposed on the guide rail, and the continuous load application module is fixedly disposed on the slide block; it also includes a drive component for driving the slide block to slide along the guide rail.

8. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 1, characterized in that: The adjustable guide rail frame is provided with a lateral support mechanism on the outside. The lateral support mechanism includes a steel bracket and an inclined support rod fixed to the steel bracket. It also includes a spring fixed to one side of the steel bracket. The spring abuts against the flange of the prestressed concrete beam in the horizontal direction.

9. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 1, characterized in that: The environmental erosion simulation module includes a water tank, a spraying mechanism, and a water pump. The water tank is open at the top and is located below the adjustable guide rail frame. The spraying mechanism includes several water pipes fixed to the adjustable guide rail frame and multiple spray heads spaced apart on the water pipes. The spray heads face the prestressed concrete beam. The water pump is used to input the erosion solution stored in the water tank into the water pipes.

10. The adaptive compensation prestressed concrete beam environmental-load coupling test device according to claim 1, characterized in that: One end of the steel strand of the prestressed concrete beam is connected to the positive terminal of a constant current power supply, and the negative terminal of the constant current power supply is connected to a stainless steel mesh fixed on the prestressed concrete beam to accelerate the electrochemical corrosion of the steel strand.

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