A coupled testing device for fatigue-corrosion-wear of steel wire in bridges under tension, bending, shear, and torsion.

Abstract

This invention discloses a coupled testing device for fatigue-corrosion-wear of bridge steel wire under tension, bending, shear, and torsion, comprising a fatigue testing machine, a corrosion component, a torsion loading component, a wear loading component, a bending loading component, and a shear loading component. The fatigue testing machine applies tensile loads to the test steel wire; the corrosion component exposes the test steel wire, located within a corrosion chamber, to a salt spray corrosion environment; the torsion loading component drives the test steel wire to twist; the wear loading component includes a pipe clamp and an auxiliary steel wire; the bending loading component applies a bending load at a set frequency to the bending loading end face; and the shear loading component applies upper and lower shear loads at set frequencies to the test steel wire. This invention can be used to simulate the coupled effects of tension, bending, shear, and torsion fatigue loads, environmental erosion, and fretting wear within the cable wire during the service life of bridge steel wire. It can quickly combine the various devices to accurately reveal the damage mechanism of bridge steel wire.

Description

Technical Field

[0001] This invention relates to the field of bridge testing technology, and in particular to a coupled testing device for fatigue-corrosion-wear of steel wires used in bridges under tension, bending, shear, and torsion. Background Technology

[0002] Suspension bridges, cable-stayed bridges, and arch bridges are widely chosen as the primary structural components for projects like the Lianjiang Cross-Sea Bridge due to their superior spanning capacity and efficient material utilization. The main cables and suspenders of suspension bridges, the stay cables of cable-stayed bridges, and the suspenders of arch bridges, as the main load-bearing components of the bridge structure, typically utilize parallel steel wires that are easy to process, transport, and possess high strength. However, due to the complex service environment of these bridge cables, coupled fatigue effects of axial tension, bending, torque, and shear forces occur under vehicle loads, wind loads, and temperature loads. Simultaneously, relative slippage between parallel steel wires leads to fretting wear. After the sheath is damaged, corrosive media in the environment erode the coating and the steel wire itself. Under the combined effects of corrosion and wear, pitting and abrasion marks typically develop on the steel wires. Under tensile, bending, shear, and torsional fatigue loads, cracks begin to initiate near the damaged area and propagate under the influence of multiple factors, ultimately leading to instantaneous failure when the steel wire reaches its ultimate bearing capacity. The unpredictable fracture of bridge cables poses safety hazards to bridges in service and also results in extremely high cable replacement costs.

[0003] Obviously, due to the sheer number of bridge cables, experiments are typically conducted on individual steel wires, generally employing a combination of fatigue testing devices, accelerated corrosion testing devices, and lateral loading devices. Fatigue testing devices typically utilize electro-hydraulic servo fatigue testing machines; accelerated corrosion testing devices mainly fall into two categories: salt spray corrosion chambers or electrolytic accelerated corrosion modules; lateral loading devices primarily create compression by using loading blocks on both sides of the test steel wire in conjunction with auxiliary steel wires. However, in actual testing, the following shortcomings exist and require improvement:

[0004] 1. It requires modification to the electro-hydraulic servo fatigue testing machine, which is not only complicated in design and modification, but also lacks the function of reuse.

[0005] 2. Current lateral loading devices only consider the wear effect of the transverse steel wires on the test steel wire, so they cannot truly reflect the extrusion force between the steel wires, and the wear mechanism cannot be well revealed through experiments.

[0006] 3. Currently, there is no study that takes into account the effects of bending, shear, and torsional fatigue loads in multi-factor coupled tests to reveal the damage mechanism of bridge steel wires.

[0007] Therefore, there is an urgent need for a convenient and reusable bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device to simulate the damage process of bridge steel wire. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a coupled testing device for tension, bending, shear and torsion fatigue-corrosion-wear of bridge steel wires. This coupled testing device can simulate the synchronous coupled testing of tension, bending, shear and torsion fatigue, corrosion and wear of steel wires, and accurately reveal the damage mechanism and deterioration law of bridge steel wires.

[0009] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0010] A coupled testing device for fatigue-corrosion-wear of steel wires used in bridges, comprising a fatigue testing machine, a corrosion component, a torsion loading component, a wear loading component, a bending loading component, and a shear loading component.

[0011] The fatigue testing machine has an upper clamp and a lower clamp; the upper clamp is located directly above the lower clamp and its height can be raised and lowered; the upper and lower clamps can vertically clamp both ends of the test wire and apply an axial tensile load to the test wire.

[0012] The corrosion assembly includes a corrosion chamber and a spray pipe; the corrosion chamber is coaxially mounted on the top of the lower clamp, and vertical holes are provided at the center of the top and bottom of the corrosion chamber for the test steel wire to slide through.

[0013] The spray pipe can spray atomized corrosive liquid into the corrosion chamber, so that the test steel wire located in the corrosion chamber is in a salt spray corrosion environment.

[0014] The torsion loading assembly includes a torsion motor mounted on a fatigue testing machine, which drives the test steel wire located above the corrosion chamber to twist.

[0015] The wear loading assembly includes a seat clamp and an auxiliary steel wire.

[0016] The tube clamp is an open ring with a test wire through hole at its center, allowing the test wire to pass freely through it. The outer periphery of the test wire through hole has several arc-shaped limiting grooves that are all connected to the test wire through hole, and each arc-shaped limiting groove can hold one of the auxiliary wires.

[0017] Two interlocking open lugs are provided on the outer side of the opening of the tube clamp; the two open lugs are installed on the fatigue testing machine, with a fixed height and position, and can slide horizontally; the middle of the two open lugs is connected by a compression screw and a compression nut; the two open lugs are formed as bending loading end faces away from the vertical wall of the test wire hole.

[0018] The bending loading assembly includes a bending loader and a bending loading rod. The bending loading rod is horizontally positioned, with one end able to come into close contact with the bending loading end face, and the other end sliding through the side wall of the corrosion chamber and connected to the bending loader. Under the drive of the bending loader, the bending loading rod can apply a bending load of a set frequency f to the bending loading end face.

[0019] The shear loading assembly includes an upper shear loader, an upper shear loading rod, a lower shear loader, and a lower shear loading rod.

[0020] The upper shear loading rod is horizontally positioned on the upper right side of the pipe clamp. One end of the rod can be in close contact with the test wire above the auxiliary wire, while the other end slides through the right side wall of the corrosion chamber and is connected to the upper shear loading machine. Driven by the upper shear loading machine, the upper shear loading rod can apply an upper shear load of a set frequency f to the test wire above the auxiliary wire.

[0021] The lower shear loading rod is horizontally positioned on the lower left side of the tube clamp. One end of the rod can be in close contact with the test steel wire below the tube clamp, while the other end slides through the sealed left side wall of the corrosion chamber and is connected to the lower shear loading machine. Driven by the lower shear loading machine, the lower shear loading rod can apply a lower shear load of a set frequency f to the test steel wire below the tube clamp. The upper shear load and the lower shear load are in phase.

[0022] When the bending loading component and the shear loading component work simultaneously, the phase difference between the upper shear load or the lower shear load and the bending load is half a cycle.

[0023] By controlling the activation timing of the fatigue testing machine, torsion loading assembly, wear loading assembly, bending loading assembly, and shear loading assembly, it is possible to simulate the fatigue-corrosion-wear conditions of the test steel wire under tension-bending, tension-torsion, tension-shear, tension-bending-torsion, tension-bending-shear, tension-torsion-bending, tension-torsion-shear, and tension-bending-shear-torsion fatigue-corrosion-wear conditions.

[0024] The test steel wires are the main cable of a suspension bridge, the suspenders of a suspension bridge, the stay cables of a cable-stayed bridge, or the suspenders of an arch bridge.

[0025] It also includes a temperature control component, which can control the internal temperature of the corrosion chamber, thereby simulating the actual ambient temperature where the steel wire is working.

[0026] The corrosion assembly also includes a salt spray concentration measuring device; the salt spray concentration measuring device can be used to measure the concentration of the corrosive liquid in the corrosion chamber; and the spray volume of the spray pipe can be adjusted according to the concentration of the corrosive liquid in the corrosion chamber.

[0027] The salt spray concentration measuring device includes a pH meter, a mist exhaust pipe, and a measuring cylinder. The mist exhaust pipe is located at the bottom of the corrosion chamber, and its outlet is connected to the measuring cylinder. The measuring cylinder can measure the total amount of corrosion liquid discharged within a set time. The pH meter is used to detect the pH value of the corrosion liquid in the corrosion chamber in real time. Based on the total amount of corrosion liquid discharged and the pH value, the concentration of the corrosion liquid at the current moment can be calculated.

[0028] The torsion loading assembly also includes an upper horizontal plate, which is horizontally mounted on the fatigue testing machine, and the torsion motor is mounted on the upper horizontal plate.

[0029] The wear loading assembly also includes a lower horizontal plate, which is horizontally slidably mounted on the fatigue testing machine. The two open lugs of the seat clamp are detachably mounted on the top side of the lower horizontal plate. The bending loading rod and the lower shear loading rod are located on the upper and lower sides of the lower horizontal plate, respectively.

[0030] The wear loading assembly has six auxiliary steel wires, the diameter of which is the same as that of the test steel wire; the seat clamp has six arc-shaped limiting grooves; the diameter of the test steel wire through hole in the seat clamp is not less than 1.5 times the diameter of the test steel wire; the extrusion force between the test steel wire and the auxiliary steel wire can be adjusted by adjusting the extrusion screw and the extrusion nut.

[0031] The present invention has the following beneficial effects:

[0032] 1. The torsion motor, lateral actuator, corrosion chamber, and seat clamp are easy to install and disassemble, and can be quickly integrated with the fatigue testing machine. They are also easy to disassemble for reuse, which improves efficiency and economy.

[0033] 2. The corrosion chamber can update the spraying frequency in real time according to the pH value of the chamber to ensure the stability of the concentration of corrosive substances in the chamber. Moreover, the bending, shearing and torsion fatigue operation table can be operated in a unified manner, realizing any combination of various fatigue load conditions.

[0034] 3. It can simulate the synchronous coupled test of steel wire tension, bending, shear and torsion fatigue-corrosion-wear, and accurately reveal the damage mechanism and deterioration law of steel wire for bridges. Attached Figure Description

[0035] Figure 1 This invention demonstrates an isometric test apparatus for coupled fatigue-corrosion-wear testing of steel wire for bridges, based on the present invention. Figure 1 .

[0036] Figure 2 This invention demonstrates an isometric test apparatus for coupled fatigue-corrosion-wear testing of steel wire for bridges, based on the present invention. Figure 2 .

[0037] Figure 3 An enlarged structural schematic diagram of the torsion loading component in this invention is shown.

[0038] Figure 4 A schematic diagram of the internal structure of the corrosion chamber in this invention is shown.

[0039] Figure 5 A schematic diagram of the seat clamp in this invention is shown.

[0040] Figure 6 A schematic diagram of the wear loading component in this invention is shown.

[0041] Among them are:

[0042] 11. Base; 12. Column; 13. Horizontal beam; 14. Upper clamp; 15. Lower clamp;

[0043] 21. Corrosion chamber; 211. Support; 212. Top hole; 213. Bottom hole; 214. Left hole; 215. Right hole;

[0044] 22. Spray pipe; 221. Nozzle; 23. Exhaust pipe; 24. Measuring cylinder; 25. pH meter; 26. Collection funnel;

[0045] 31. Torsion motor; 32. Upper horizontal plate; 33. Motor mounting screw; 34. Motor mounting nut;

[0046] 41. Pipe clamp; 411. Test wire perforation;

[0047] 42. Arc-shaped limiting groove;

[0048] 413. Open lug; 413a. Bending loading end face;

[0049] 414. Extrusion hole; 414a. Extrusion screw; 414b. Extrusion nut;

[0050] 415. Vertical limiting hole; 415a. Limiting screw; 415b. Limiting nut;

[0051] 42. Lower horizontal plate; 43. Auxiliary steel wire;

[0052] 51. Bending loading rod;

[0053] 61. Upper shear loading rod; 62. Lower shear loading rod;

[0054] 70. Temperature control components;

[0055] 80. Test the steel wire. Detailed Implementation

[0056] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.

[0057] In the description of this invention, it should be understood that the terms "left side," "right side," "upper part," "lower part," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. "First," "second," etc., do not indicate the importance of the components, and therefore should not be construed as a limitation of this invention. The specific dimensions used in this embodiment are only for illustrating the technical solution and do not limit the scope of protection of this invention.

[0058] like Figure 1 and Figure 2 As shown, a bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device includes a fatigue testing machine, a corrosion component, a torsion loading component, a wear loading component, a bending loading component, a shear loading component, a temperature control component 70, and an operating table.

[0059] The fatigue testing machine includes a base 11, a column 12, a crossbeam 13, an upper clamp 14, and a lower clamp 15.

[0060] The lower clamp 15 is installed at the top center of the base, and the upper clamp is installed at the bottom center of the crossbeam and directly above the lower clamp; the upper clamp and the crossbeam can move up and down synchronously along the column under the lifting drive of the fatigue testing machine.

[0061] The upper and lower clamps are used to vertically clamp the test steel wire 80, and the axial tensile load is applied to the test steel wire by raising and lowering the height of the crossbeam. The test steel wire in this invention is preferably the main cable of a suspension bridge, the suspender cable of a suspension bridge, the stay cable of a cable-stayed bridge, or the suspender cable of an arch bridge, etc.

[0062] like Figure 1 and Figure 4 As shown, the corrosion assembly includes a corrosion chamber 21, a spray pipe 22, and a salt spray concentration measuring device.

[0063] The corrosion box is preferably coaxially mounted on the top of the lower clamp via a bracket 211. The corrosion box is preferably a square or rectangular box, and an upper hole 212, a lower hole 213, a left hole 214, and a right hole 215 are preferably provided at the center of its top plate, left side plate, and right side plate.

[0064] The aforementioned upper hole 212 and lower hole 213 are collectively referred to as vertical holes. They are located on the same vertical line and allow the test steel wire to pass through freely. It is preferable to install anti-corrosion plastic film at both the upper hole 212 and the lower hole 213 to achieve sealed isolation from the outside world.

[0065] Furthermore, in this invention, the corrosion chamber and the operating table are designed as an integrated unit. The operating table can uniformly control the fatigue testing machine, corrosion components, torsion loading components, wear loading components, bending loading components, shear loading components, and temperature control components. The operating table can also move the corrosion chamber. In other words, the corrosion chamber and the operating table are independent modular structures that can be manufactured separately. They are easy to disassemble and store later, and can be well prepared for the next test.

[0066] One end of the spray pipe is connected to a corrosion liquid tank, and the other end extends into the corrosion chamber and is connected to a nozzle 221, which can spray atomized corrosion liquid into the corrosion chamber, so that the test steel wire located in the corrosion chamber is in a salt spray corrosion environment.

[0067] The salt spray concentration measuring device described above can be used to measure the concentration of the corrosive liquid in the corrosion chamber. It includes a mist exhaust pipe 23, a measuring cylinder 24, a pH meter 25, and a collection funnel 26.

[0068] The exhaust pipe is located at the bottom of the corrosion chamber, and its top is connected to a collection funnel to collect the salt spray solution. The outlet of the exhaust pipe is connected to a metering cylinder, which measures the total amount of corrosion solution discharged within a set time. A pH meter is used to monitor the pH value of the corrosion solution in the corrosion chamber in real time. Based on the total amount of corrosion solution discharged and the pH value, the current concentration of the corrosion solution can be calculated. Therefore, the spray volume and spray interval of the spray pipe can be adjusted according to the concentration of the corrosion solution in the corrosion chamber to ensure that the concentration of the corrosion solution in the corrosion chamber is maintained at the design value.

[0069] The aforementioned temperature control components can control the internal temperature of the corrosion chamber, thereby simulating the actual ambient temperature where the steel wire operates. The temperature control components can be heating devices such as a heated water tank or heating wire, or they can be equipped with a cooling fan.

[0070] like Figure 3 As shown, the torsion loading assembly includes a torsion motor 31 and an upper horizontal plate 32.

[0071] The upper horizontal plate is horizontally mounted on the fatigue testing machine. The torsion motor is preferably detachably mounted to the upper horizontal plate via motor mounting screw 33 and motor mounting nut 34.

[0072] The aforementioned torsion motor is preferably a stepper motor, which is fitted around the test wire located above the corrosion chamber and can drive the test wire above the corrosion chamber to twist. In this embodiment, the motor shaft of the stepper motor can be set as a hollow shaft, so that the hollow shaft is fitted and locked around the test wire located above the corrosion chamber; alternatively, the rotor of the stepper motor can be directly fitted and locked around the test wire located above the corrosion chamber.

[0073] like Figure 1 and Figure 6As shown, the wear loading assembly includes a seat clamp 41, a lower cross plate 42, and an auxiliary steel wire 43.

[0074] like Figure 5 As shown, the tube clamp is an open ring with a test wire through hole 412 in the center, which allows the test wire to pass freely through it; the diameter of the test wire through hole is not less than 1.5 times the diameter of the test wire.

[0075] The outer periphery of the test wire through-hole has several arc-shaped limiting grooves 412, each connected to the test wire through-hole, and each arc-shaped limiting groove can hold an auxiliary wire. In this embodiment, there are six auxiliary wires, and the diameter of the auxiliary wires is the same as that of the test wire; there are six arc-shaped limiting grooves in the pipe clamp, and the entire pipe clamp needs to be treated with galvanized aluminum alloy for corrosion protection.

[0076] The aforementioned test wire perforation and six arc-shaped limiting grooves form a six-petaled plum blossom shape. The arc-shaped limiting grooves are blind holes, capable of supporting and placing auxiliary wires. This design allows for genuine surface-to-surface contact and compression between the test wire and the auxiliary wire.

[0077] Two merging lugs 413 are provided on the outer side of the opening of the tube clamp; each of the two lugs is provided with a vertical limiting hole 415, and each vertical limiting hole is detachably connected to the lower horizontal plate through a limiting screw 415a and a limiting nut 415b. The outer end of the lower horizontal plate preferably passes through the left hole 214 and is horizontally slidably installed on the fatigue testing machine.

[0078] Each of the two open lugs has a compression hole 414 in the middle, and each compression hole is connected by a compression screw 414a and a compression nut 414b. By adjusting the compression screw and the compression nut, the compression force between the test wire and the auxiliary wire can be adjusted.

[0079] The two open lugs are separated from the vertical wall of the test wire through hole to form a bending loading end face 413a.

[0080] The test steel wire undergoes axial tensile deformation under the action of the fatigue testing machine, which in turn causes relative slippage with the auxiliary steel wire, resulting in wear on the test steel wire.

[0081] The aforementioned bending loading assembly includes a bending loader and a bending loading rod 51. The bending loading rod is horizontally positioned, with one end in close contact with the bending loading end face, and the other end slidingly through the side wall of the corrosion chamber and connected to the bending loader. Preferably, the bending loading rod extends from the left hole of the corrosion chamber and is located at the top of the lower horizontal plate.

[0082] The bending loading rod can apply a bending load of a set frequency f to the bending loading end face under the drive of the bending loading machine.

[0083] The shear loading assembly includes an upper shear loader, an upper shear loading rod 61, a lower shear loader, and a lower shear loading rod 62.

[0084] The upper shear loading rod is horizontally positioned on the upper right side of the tube clamp. One end is in close contact with the test wire above the auxiliary wire, while the other end slides through the right side wall of the corrosion chamber and connects to the upper shear loading machine. Preferably, the upper shear loading rod exits from the right hole of the corrosion chamber.

[0085] The upper shear loading rod, driven by the upper shear loading machine, applies an upper shear load of a set frequency f to the test wire above the auxiliary wire.

[0086] The lower shear loading rod is horizontally positioned on the lower left side of the tube clamp. One end is in close contact with the test wire below the tube clamp, while the other end slides through the sealed left side wall of the corrosion chamber and connects to the lower shear loading machine. Preferably, the lower shear loading rod exits from the left hole of the corrosion chamber and is located at the bottom of the lower horizontal plate.

[0087] The lower shear loading rod, driven by the lower shear loading machine, applies a lower shear load of a set frequency f to the test wire below the seat clamp; the upper shear load and the lower shear load are in phase.

[0088] The upper and lower shear loading rods mentioned above have the same height difference with the seat clamp.

[0089] The aforementioned bending loader, upper shear loader, and lower shear loader are all preferably horizontally arranged hydraulic actuators (also called lateral actuators). Therefore, the bending loading rod, upper shear loading rod, and lower shear loading rod are all preferably piston rods connected to the piston in the hydraulic actuator. Both the hydraulic actuator and the piston rod need to be treated with galvanized aluminum alloy for corrosion protection.

[0090] When the bending and shear loading components operate simultaneously, the set frequency f of the upper or lower shear load and the bending load are the same, but the phase difference is half a cycle. This ensures the correct loading of bending fatigue load and shear fatigue load. The half-cycle phase difference ensures that when one set of lateral actuators applies maximum load to the wire under shear or bending loads, the other lateral actuator is under zero load. Therefore, the deformation of the wire caused by the former load will be minimized when the latter loads, thus minimizing the mutual influence between the two loads on the wire's deformation and accurately simulating the bending and shear loads on the wire.

[0091] By controlling the start-up timing of the fatigue testing machine, torsion loading component, wear loading component, bending loading component, and shear loading component, and by controlling the phase difference between the fatigue testing machine, torsion motor, and hydraulic actuation cylinder, any combination of the peak loads of tension, torsion, bending, and shear on the test steel wire at the same moment can be achieved. In other words, the simulation of fatigue-corrosion-wear conditions of tension-bending, tension-torsion, tension-shear, tension-bending-torsion, tension-bending-shear, tension-torsion-bending, tension-torsion-shear, and tension-bending-shear-torsion on the test steel wire can be achieved, thus comprehensively covering the complex mechanical state of bridge steel wire.

[0092] Therefore, under the combined action of the above-mentioned equipment, the bridge steel wire will experience a coupled effect of tensile-bending-shear-torsional fatigue-corrosion-wear until the steel wire breaks, at which point the test stops. This invention can be used to simulate the coupled effect of tensile-bending-shear-torsional fatigue loads, environmental erosion, and fretting wear within the cable wires during the service life of bridge steel wires. It can quickly combine various devices to accurately reveal the damage mechanism of bridge steel wires.

[0093] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the protection scope of the present invention.

Claims

1. A coupled testing device for fatigue-corrosion-wear of steel wire used in bridges under tension, bending, shear, and torsion, characterized in that: This includes fatigue testing machines, corrosion components, torsion loading components, wear loading components, bending loading components, and shear loading components; The fatigue testing machine has an upper clamp and a lower clamp; the upper clamp is located directly above the lower clamp and its height can be adjusted; the upper and lower clamps can vertically clamp both ends of the test wire and apply an axial tensile load to the test wire. The corrosion assembly includes a corrosion chamber and a spray pipe; the corrosion chamber is coaxially mounted on the top of the lower clamp, and vertical holes are provided at the center of the top and bottom of the corrosion chamber for the test steel wire to slide through in a sealed manner; The spray pipe can spray atomized corrosive liquid into the corrosion chamber, so that the test steel wire located in the corrosion chamber is in a salt spray corrosion environment; The torsion loading assembly includes a torsion motor mounted on a fatigue testing machine, which drives the test steel wire located above the corrosion chamber to twist. The wear loading assembly includes a seat clamp and an auxiliary steel wire; The tube clamp is an open ring with a test wire through hole in the center for the test wire to pass through freely. The outer periphery of the test wire through hole has several arc-shaped limiting grooves that are all connected to the test wire through hole, and each arc-shaped limiting groove can hold one of the auxiliary wires. Two interlocking open lugs are provided on the outer side of the opening of the tube clamp; the two open lugs are installed on the fatigue testing machine, with a fixed height and position, and can slide horizontally; the middle of the two open lugs is connected by a compression screw and a compression nut; the two open lugs are formed as bending loading end faces away from the vertical wall of the test wire hole. The bending loading assembly includes a bending loader and a bending loading rod. The bending loading rod is horizontally positioned, with one end able to come into close contact with the bending loading end face, and the other end sliding through the side wall of the corrosion chamber and connected to the bending loader. Under the drive of the bending loader, the bending loading rod can apply a bending load of a set frequency f to the bending loading end face. The shear loading assembly includes an upper shear loader, an upper shear loading rod, a lower shear loader, and a lower shear loading rod; The upper shear loading rod is horizontally set on the upper right side of the pipe clamp. One end can be in close contact with the test wire above the auxiliary wire, and the other end slides through the right side wall of the corrosion chamber and is connected to the upper shear loading machine. The upper shear loading rod can apply an upper shear load of a set frequency f to the test wire above the auxiliary wire under the drive of the upper shear loading machine. The lower shear loading rod is horizontally positioned on the lower left side of the tube clamp. One end of the rod can be in close contact with the test steel wire below the tube clamp, while the other end slides through the sealed left side wall of the corrosion chamber and is connected to the lower shear loading machine. Driven by the lower shear loading machine, the lower shear loading rod can apply a lower shear load of a set frequency f to the test steel wire below the tube clamp. The upper shear load and the lower shear load are in phase. When the bending loading component and the shear loading component work simultaneously, the phase difference between the upper shear load or the lower shear load and the bending load is half a cycle.

2. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device according to claim 1, characterized in that: By controlling the activation timing of the fatigue testing machine, torsion loading assembly, wear loading assembly, bending loading assembly, and shear loading assembly, it is possible to simulate the fatigue-corrosion-wear conditions of the test steel wire under tension-bending, tension-torsion, tension-shear, tension-bending-torsion, tension-bending-shear, tension-torsion-bending, tension-torsion-shear, and tension-bending-shear-torsion fatigue-corrosion-wear conditions.

3. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device according to claim 1, characterized in that: The test steel wires are the main cable of a suspension bridge, the suspenders of a suspension bridge, the stay cables of a cable-stayed bridge, or the suspenders of an arch bridge.

4. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled test device according to claim 1, characterized in that: It also includes a temperature control component, which can control the internal temperature of the corrosion chamber, thereby simulating the actual ambient temperature where the steel wire is working.

5. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device according to claim 1, characterized in that: The corrosion assembly also includes a salt spray concentration measuring device; the salt spray concentration measuring device can be used to measure the concentration of the corrosive liquid in the corrosion chamber; and the spray volume of the spray pipe can be adjusted according to the concentration of the corrosive liquid in the corrosion chamber.

6. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device according to claim 5, characterized in that: The salt spray concentration measuring device includes a pH meter, a mist exhaust pipe, and a measuring cylinder; the mist exhaust pipe is located at the bottom of the corrosion chamber, and its outlet is connected to the measuring cylinder; the measuring cylinder can measure the total amount of corrosion liquid discharged within a set time. The pH meter is used to detect the pH value of the corrosion solution in the corrosion chamber in real time; based on the total amount of corrosion solution discharged and the pH value, the concentration of the corrosion solution at the current moment can be calculated.

7. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device according to claim 1, characterized in that: The torsion loading assembly also includes an upper horizontal plate, which is horizontally mounted on the fatigue testing machine, and the torsion motor is mounted on the upper horizontal plate.

8. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device according to claim 1, characterized in that: The wear loading assembly also includes a lower horizontal plate, which is horizontally slidably mounted on the fatigue testing machine. The two open lugs of the seat clamp are detachably mounted on the top side of the lower horizontal plate. The bending loading rod and the lower shear loading rod are located on the upper and lower sides of the lower horizontal plate, respectively.

9. The bridge steel wire tension-bending-shear-torsion fatigue-corrosion-wear coupled testing device according to claim 1, characterized in that: The wear loading assembly has six auxiliary steel wires, the diameter of which is the same as that of the test steel wire; the seat clamp has six arc-shaped limiting grooves; the diameter of the test steel wire through hole in the seat clamp is not less than 1.5 times the diameter of the test steel wire; the extrusion force between the test steel wire and the auxiliary steel wire can be adjusted by adjusting the extrusion screw and the extrusion nut.

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