A method for preparing a stress-coupled filament electrode

Abstract

The application provides a kind of coupling stress filament preparation integrated device, the device includes: passivation box, including box and box cover, the box and box cover are hinged, water inlet pipe and drain pipe are arranged on the wall surface of the box;Stress loading device, the stress loading device is arranged in the box, including support unit, sliding unit and clamping unit, the filament is fixed on two relatively arranged clamping units, the clamping unit is fixed on the sliding unit, the sliding unit is fixed on the support unit, and stress is applied to the filament by the sliding movement of sliding unit.The device is simple in structure, easy to operate, can realize the synchronous operation of filament passivation and stress application, so that the test of steel bar corrosion is closer to the actual state of engineering, and the accuracy of test is improved.

Description

Technical Field

[0001] This invention belongs to the field of wire bundle electrode preparation technology, specifically relating to a method for preparing wire bundle electrodes with coupled stress. Background Technology

[0002] Steel reinforcement corrosion is a major cause of damage to concrete structures in marine engineering. Globally, corrosion losses average 2% to 4% of GDP, with steel reinforcement corrosion accounting for as much as 40% of these losses. Chloride ion corrosion in concrete is a non-uniform, localized electrochemical corrosion primarily characterized by pitting. The mechanical properties of corroded steel reinforcement deteriorate sharply, and rust expansion and cracking lead to further corrosion. Wire bundle electrodes, as an array electrode, can measure the corrosion potential and current density of individual microelectrodes within their corresponding regions to detect the entire electrochemical corrosion process and its non-uniformity at the metal interface, providing a new approach for studying localized metal corrosion.

[0003] Traditional wire bundles generally do not bear stress, while the reinforcing bars in concrete structural members in actual engineering projects all bear a certain amount of stress. This is inconsistent with engineering reality. The effect of chloride ion concentration on steel corrosion measured in experiments deviates from engineering reality to a certain extent. Furthermore, the wire bundle should be passivated before applying coupled stress. Currently, there is no device that can simultaneously achieve the functions of wire bundle passivation and stress application. Therefore, how to apply stress to the wire bundle, making it bear different stress levels, while simultaneously achieving wire bundle passivation, so as to avoid the influence of wire bundle corrosion on the test results, and improve the experimental precision and accuracy of the effect of chloride ions in concrete on steel corrosion.

[0004] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing a wire bundle electrode with coupled stress, so as to at least solve the problem that there is currently no device that can simultaneously achieve wire bundle passivation and stress coupling.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for fabricating a wire bundle electrode with coupled stress, the apparatus comprising:

[0008] A passivation box includes a box body and a box cover, the box body and the box cover are hinged together, and a water inlet pipe and a water outlet pipe are provided on the wall of the box body;

[0009] A stress loading device is disposed inside the housing and includes a support unit, a sliding unit, and a clamping unit. The filament bundle is fixed on two oppositely arranged clamping units, the clamping units are fixed on the sliding units, and the sliding units are fixed on the support unit. Stress is applied to the filament bundle through the sliding movement of the sliding units.

[0010] In the above-described method for fabricating wire bundle electrodes under coupled stress, preferably, the support unit includes a support plate and a support block arranged vertically opposite each other.

[0011] In the above-described method for preparing a wire bundle electrode with coupled stress, preferably, the sliding unit is a lead screw and nut mechanism, the clamping unit includes a first fixing plate and a second fixing plate, one end of the lead screw passes through the support plate and the other end is connected to the support block, the nut is a nut seat, the first fixing plate is fixed above the nut seat, the second fixing plate is provided on the support block, and the two ends of the wire bundle are respectively fixed to the first fixing plate and the second fixing plate.

[0012] In the above-described method for preparing a wire bundle electrode under coupled stress, preferably, the top surface of the nut seat and the top surface of the support plate are on the same horizontal line.

[0013] In the above-described method for preparing a wire bundle electrode with coupled stress, preferably, the device further includes two support rods, which are arranged parallel to each other on both sides of the lead screw. One end of each support rod is fixed to the support plate, and the other end is fixed to the support block. The support rods are arranged parallel to the lead screw, and the support rods pass through the nut seat.

[0014] In the above-described method for fabricating wire bundle electrodes under coupled stress, preferably, multiple uniformly arranged wire bundles are fixed between the clamping units.

[0015] Preferably, the filament bundle is made of carbon steel, with a diameter of 3-5 mm and a length of 15-20 cm.

[0016] In the method for preparing a wire bundle electrode with coupled stress as described above, preferably, a plurality of mounting holes are provided on the wall surfaces of the first fixing plate and the second fixing plate, and a prestressed locking plate is provided in the mounting hole, and the wire bundle is fixed on the prestressed locking plate.

[0017] In the above-described method for fabricating wire bundle electrodes under coupled stress, preferably, a fan is provided inside the box cover.

[0018] In the above-described method for preparing a wire bundle electrode with coupled stress, preferably, the device further includes a sleeve, which is fitted around the periphery of the wire bundle and filled with epoxy resin to connect multiple wire bundles into an integral structure.

[0019] In the above-described method for preparing a wire bundle electrode with coupled stress, preferably, a rotating handle is connected to one end of the lead screw located outside the support plate.

[0020] Beneficial effects:

[0021] The device of this invention can both passivate the wire bundle and apply different degrees of stress to the wire bundle. During loading, different stresses can be applied to the wire bundle according to different displacements of the loading device, resulting in passivated wire bundle electrodes under different stress states. This simulates the stress state of steel bars in actual engineering projects. Furthermore, during the experiment, the corrosion status of chloride ions on steel bars at different locations under different stress states is determined, and the critical chloride ion for steel bar corrosion is obtained, thereby improving the accuracy of the test.

[0022] Artificial intervention when the critical chloride ion concentration is exceeded has important engineering significance for the durability design of long-life concrete, and solves the shortcoming of using unstressed wire bundles as electrode materials to detect the critical chloride ion concentration.

[0023] The device of the present invention has a simple structure and is easy to operate. It realizes the simultaneous operation of wire passivation and stress application, and the test of steel bar corrosion is closer to the actual engineering condition, thus improving the accuracy of the test. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein:

[0025] Figure 1 This is a schematic diagram of the overall structure of the integrated device for fabricating wire bundle electrodes with coupled stress according to an embodiment of the present invention.

[0026] Figure 2 for Figure 1 A top view of the device after it has been opened;

[0027] Figure 3 for Figure 1 Front view of the stress loading device in the middle;

[0028] Figure 4 for Figure 3 Top view;

[0029] Figure 5 for Figure 3 A schematic diagram of the structure of the clamping unit after the filament bundle is inserted;

[0030] Figure 6 for Figure 5 Cross-sectional view of the prestressed locking plate installed in the mounting hole.

[0031] In the diagram: 1. Rotating handle, 2. Lead screw, 3. Nut seat, 4. Support column, 5. First fixing plate, 6. Second fixing plate, 7. Passivation box, 8. Fan, 9. Water inlet pipe, 10. Drainage pipe, 11. Mounting hole, 12. Hoop, 13. Prestressed locking plate, 14. Support rod, 15. Wire bundle, 16. Sealing gasket, 17. Support plate, 18. Support block. Detailed Implementation

[0032] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0033] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0034] like Figures 1 to 6 As shown, according to an embodiment of the present invention, a method for preparing a wire bundle electrode with coupled stress is provided, the apparatus including a passivation box 7 and a stress loading device.

[0035] The device of the present invention can passivate, clean, and dry the wire bundle 15 electrode, and apply stress to the wire bundle 15. In actual engineering, the steel bars in reinforced concrete structural members often hold a certain stress. The critical concentration at which the steel bars begin to rust is different under different stress states. The present invention can preset different stress states for the wire bundle 15 electrode according to different displacements of the measuring device. The critical chloride ion concentration measured by the wire bundle 15 electrode under different stress states reflects the critical chloride ion concentration of the steel bars under different stress states, thereby reflecting the corrosion status of the steel bars.

[0036] The passivation chamber 7 includes a chamber body and a cover, which are hinged together. A water inlet pipe 9 and a drain pipe 10 are installed on the chamber body wall. The passivation chamber 7 is used to hold an alkaline solution to passivate the wire bundle 15 during the stress application process. This ensures that any steel corrosion that occurs during the test is caused by chloride ions from the concrete being transferred to the steel reinforcement, rather than by corrosion inherent in the steel reinforcement itself.

[0037] A sealing gasket 16 is embedded on the lower end surface of the box lid to achieve overall airtightness of the passivation box 7. Specifically, the sealing gasket 16 is a rubber sealing gasket. Preferably, the passivation box 7 is made of high-density polyethylene material.

[0038] The water inlet pipe 9 is located at the upper part of the tank, and the drain pipe 10 is located at the lower part of the tank. Both the water inlet pipe 9 and the drain pipe 10 are equipped with valves. Preferably, the water inlet pipe 9 and the drain pipe 10 are made of high-density polyethylene. The diameter of both the water inlet pipe 9 and the drain pipe 10 is 2-3cm (e.g., 22cm, 24cm, 26cm, 28cm).

[0039] The stress loading device is installed inside the housing and includes a support unit, a sliding unit, and a clamping unit. The filament bundle 15 is fixed on two clamping units arranged opposite to each other. The clamping unit is fixed on the sliding unit, and the sliding unit is fixed on the support unit. Stress is applied to the filament bundle 15 through the sliding movement of the sliding unit.

[0040] In a specific embodiment of the present invention, the support unit includes a support plate 17 and a support block 18 arranged vertically opposite each other.

[0041] In a specific embodiment of the present invention, the sliding unit is a lead screw 2 nut mechanism, the clamping unit includes a first fixing plate 5 and a second fixing plate 6, one end of the lead screw 2 passes through the support plate 17, and the other end is connected to the support block 18, the nut is a nut seat 3, the first fixing plate 5 is fixed above the nut seat 3, the second fixing plate 6 is provided on the support block 18, and the two ends of the wire bundle 15 are respectively fixed on the first fixing plate 5 and the second fixing plate 6.

[0042] In a specific embodiment of the present invention, multiple evenly arranged wire bundles 15 are fixed between the clamping units; specifically, there are 25 wire bundles 15, and the material of the wire bundles 15 is carbon steel. Ordinary carbon steel has a low critical chloride ion concentration, is prone to rusting and passivation, and has high sensitivity. The number and position of the wire bundles 15 are determined according to actual needs. The diameter of the wire bundles 15 is 3-5mm (e.g., 35mm, 4mm, 45mm, 5mm), and the length is 15-20cm (e.g., 16cm, 17cm, 18cm, 19cm).

[0043] The filament bundle 15 is connected to the first fixing plate 5 and the second fixing plate 6 by a fixing device or welding. Preferably, the fixing device is a prestressed locking plate 13, which includes two clamping plates that lock the filament bundle 15 onto the first fixing plate 5 and the second fixing plate 6. Multiple mounting holes 11 are provided on the walls of the first fixing plate 5 and the second fixing plate 6, and the prestressed locking plates 13 are disposed within the mounting holes 11, fixing the filament bundle 15 to the prestressed locking plates 13. Of course, the fixing device can also be other types of mechanisms that can fix the filament bundle 15 to the two fixing plates; this invention is not limited to these.

[0044] In a specific embodiment of the present invention, the device is further provided with support columns 4, which are attached to the side walls of the first fixing plate 5 and the second fixing plate 6 that are disposed opposite to each other. Specifically, two support columns 4 are provided on both sides of the side wall of the first fixing plate 5, and two support columns 4 are also provided on both sides of the side wall of the second fixing plate 6. The support columns 4 are used to resist the fixing plates and buffer the force on the two fixing plates in order to improve the stability of the structure.

[0045] In a specific embodiment of the present invention, a rotating handle 1 is connected to one end of the lead screw 2 located outside the support plate 17. By rotating the rotating handle 1, the nut seat 3 on the lead screw 2 is moved, and the nut seat 3 causes the first fixed plate 5 to slide a certain distance, so that the wire bundle 15 is subjected to a certain degree of tensile stress. The greater the sliding distance, the greater the tensile stress. Different degrees of tensile stress can be obtained by adjusting the sliding distance.

[0046] In a specific embodiment of the present invention, the top surface of the nut seat 3 and the top surface of the support plate 17 are on the same horizontal line. The mounting holes 11 between the first fixing plate 5 and the second fixing plate 6 correspond to each other, and the multiple wire bundles 15 are all in a horizontal position, so that the force is uniform.

[0047] In a specific embodiment of the present invention, the device further includes two support rods 14, which are arranged parallel to each other on both sides of the lead screw 2. One end of the support rod 14 is fixed to a support plate 17, which has corresponding slots, and the other end is fixed to a support block 18, which also has corresponding slots. The support rod 14 and the lead screw 2 are arranged parallel to each other, and the support rod 14 passes through the nut seat 3. Specifically, two sleeves are provided below the nut seat 3, and the sleeves are fitted onto the support rods 14. The support rods 14 can improve the support stability of the sliding unit. Preferably, the support rods 14 can be metal rods with a relatively smooth surface, which is conducive to the smooth sliding of the nut seat 3.

[0048] In a specific embodiment of the present invention, a fan 8 is provided inside the box cover. The passivated filament bundle 15 can be quickly dried by the fan 8.

[0049] In a specific embodiment of the present invention, the device further includes a sleeve 12, which is fitted around the periphery of the filament bundle 15. After the filament bundle 15 has been prestressed and passivated, epoxy resin can be injected into the sleeve 12 to connect multiple filament bundles 15 into an integral structure. The sleeve 12 is fitted around the periphery of the filament bundle 15 before the filament bundle 15 is installed in the clamping unit.

[0050] In a specific embodiment of the present invention, the device further includes a scale for measuring the distance of displacement of the sliding unit in order to calculate the stress of the filament bundle 15.

[0051] The stress calculation method for the filament bundle 15 in this invention is as follows:

[0052] The elastic modulus E of the test wire bundle 15 is determined by the mechanical property parameters of the test wire bundle 15. The device can measure the length L of the test wire bundle 15, which is also the distance between the first fixed plate 5 and the second fixed plate 6. After applying displacement, the elongation ΔL of the wire bundle 15 is recorded, and the strain ε of the wire bundle 15 can be obtained. The stress σ of the wire bundle 15 can be calculated according to the formula (1). Depending on the different sliding distances, the stretching length of the wire bundle 15 is different, and different degrees of stress can be applied to the wire bundle 15.

[0053] σ=E×ε (1)

[0054] In formula (1), E is the elastic modulus of the test wire bundle 15; σ is the stress of the test wire bundle 15; and ε is the strain of the test wire bundle 15.

[0055] The integrated device for preparing coupled stress wire bundle 15 of the present invention first performs stress tensioning and then passivation treatment during use. The specific steps are as follows:

[0056] First, the silk bundle is stretched 15 times;

[0057] First, assemble the stress loading device, and then install the wire bundles 15 with sleeves 12 on the first fixing plate 5 and the second fixing plate 6. All the installed wire bundles 15 are in a horizontal state.

[0058] Measure the distance between the first fixed plate 5 and the second fixed plate 6 when the filament bundle 15 is not under stress. Rotate the handle 1 to stretch the filament bundle 15. The nut seat 3 drives the first fixed plate 5 to slide outward, and the filament bundle 15 is in a tensioned state. The sliding distance is ΔL, that is, the elongation of the filament bundle 15 is ΔL. Determine the elastic modulus E of the filament bundle 15, calculate the strain ε of the filament bundle 15, and then calculate the stress σ of the filament bundle 15 in this state using formula (1). The tensioning of the filament bundle 15 is completed. Different horizontal stress loads can be applied according to requirements to obtain filament bundles 15 with different coupling stresses.

[0059] Second, the filament bundle 15 is passivated;

[0060] The stress loading device with wire bundle 15 is placed inside the chamber. First, strong acid is added to the passivation chamber 7 through the water inlet pipe 9 to remove rust. After 2-3 minutes, the drain pipe 10 is opened to drain the waste liquid, and then the valve of the drain pipe 10 is closed. Next, clean water is poured into the passivation chamber 7 through the water inlet pipe 9 to rinse the surface of the strong acid on the wire bundle 15. The valve of the drain pipe 10 is then opened to drain the waste liquid, and then the valve of the drain pipe 10 is closed. Next, a saturated Ca(OH)2 solution with pH=125 is poured into the water inlet pipe 9, and the valve of the water inlet pipe 9 is closed to begin passivating the wire bundle 15 electrode.

[0061] After 6-8 days, open valve 10 of the drain pipe to discharge the waste liquid. After the waste liquid is discharged, close valve 10 of the drain pipe. Open valve 9 of the inlet pipe, pour in ethanol solution, and clean the saturated Ca(OH)2 solution from the surface of the fiber bundle 15. Open valve 10 of the drain pipe to discharge the waste liquid. Turn on fan 8. After the surface of the fiber bundle 15 dries, the passivation process is complete.

[0062] Third, the fabrication of the coupled stress wire bundle 15 electrode;

[0063] One end of the sleeve 12 is sealed with hot melt adhesive to ensure that no leakage occurs when the epoxy resin is poured. Epoxy resin is poured into the sleeve 12 for encapsulation. After the epoxy resin has cured, the wire bundle 15 is removed from the clamping unit. Excess wire bundle 15 and hot melt adhesive are cut off with a cutting machine. Before the test, the electrode working surface (bottom surface) of the wire bundle 15 is polished to a smooth finish on a metallographic polishing machine with 240 grit, 400 grit, 800 grit and 1000 grit wet sandpaper. Then it is cleaned with anhydrous ethanol and acetone, dried and placed in a desiccator for later use.

[0064] In summary, the device of the present invention can both passivate the wire bundle and apply different degrees of stress to the wire bundle. During loading, different stresses can be applied to the wire bundle according to different displacements of the loading device, resulting in passivated wire bundle electrodes under different stress states. This simulates the stress state of steel bars in actual engineering projects. Furthermore, during the experiment, the corrosion status of chloride ions on steel bars at different locations under different stress states can be determined, and the critical chloride ion for steel bar corrosion can be obtained, thereby improving the accuracy of the test.

[0065] Artificial intervention when the critical chloride ion concentration is exceeded has important engineering significance for the durability design of long-life concrete, and solves the shortcoming of using unstressed wire bundles as electrode materials to detect the critical chloride ion concentration.

[0066] The device of the present invention has a simple structure and is easy to operate. It realizes the simultaneous operation of wire passivation and stress application, and the test of steel bar corrosion is closer to the actual engineering condition, thus improving the accuracy of the test.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for fabricating a wire bundle electrode with coupled stress, characterized in that, The fabrication is performed using an integrated apparatus for fabricating wire bundle electrodes under coupled stress, the integrated apparatus comprising: A passivation box includes a box body and a box cover, the box body and the box cover are hinged together, and a water inlet pipe and a water outlet pipe are provided on the wall of the box body; A stress loading device, placed inside the housing, includes a support unit, a sliding unit, and a clamping unit. The sliding unit is fixed to the support unit, and stress is applied to the wire bundles through the sliding movement of the sliding unit. The support unit includes a vertically opposite support plate and a support block. The sliding unit is a screw-nut mechanism, and the nut is a nut seat. The end of the screw of the screw-nut mechanism located outside the support plate is connected to a rotating handle. The clamping unit includes a first fixing plate and a second fixing plate opposite to each other. The first fixing plate is fixed to the nut seat, and the second fixing plate is disposed on the support block. Multiple evenly arranged wire bundles are fixed between the clamping units, and the two ends of the wire bundles are respectively fixed to the first fixing plate and the second fixing plate. A sleeve, which is fitted around the filament bundle and filled with epoxy resin, is used to connect multiple filament bundles into a single structure. The method for fabricating the wire bundle electrode under coupled stress includes the following steps: First, tensioning of the silk bundle; Assemble the stress loading device, and then install the wire bundles with sleeves on the first and second fixed plates. All the installed wire bundles are in a horizontal state. Measure the distance between the first and second fixed plates when the filament bundle is not under stress. Rotate the handle, and the nut seat will cause the first fixed plate to slide outward by a distance of ΔL. Apply horizontal stress to the filament bundle to stretch it and obtain a filament bundle with coupled stress. The stretching length of the filament bundle is different depending on the sliding distance ΔL. Apply different degrees of stress to the filament bundle according to the requirements. Second, the stress loading device with the filament bundle is placed inside the box to passivate the filament bundle; Third, the fabrication of wire bundle electrodes for coupled stress; One end of the sleeve is sealed with hot melt adhesive, and epoxy resin is poured into the sleeve for encapsulation. After the epoxy resin cures, the wire bundle is removed from the clamping unit, and the excess wire bundle and hot melt adhesive are cut off with a cutting machine to obtain the wire bundle electrode.

2. The method for fabricating a wire bundle electrode with coupled stress as described in claim 1, characterized in that, The stress calculation method for the filament bundle is as follows: the elastic modulus E of the filament bundle to be tested is determined by the mechanical property parameters of the filament bundle to be tested, the strain ε of the filament bundle is obtained according to the slip distance ΔL, and then the stress σ of the filament bundle is calculated according to formula (1); formula (1) is: σ = E × ε (1; In formula (1), E is the elastic modulus of the filament bundle to be tested; σ is the stress of the filament bundle to be tested; and ε is the strain of the filament bundle to be tested.

3. The method for fabricating a wire bundle electrode with coupled stress as described in claim 1, characterized in that, The specific steps for placing the stress loading device with the filament bundle inside the chamber to passivate the filament bundle are as follows: Place the stress loading device with the wire bundle inside the chamber. First, add strong acid to the passivation chamber through the water inlet pipe to remove rust. After 2-3 minutes, open the drain pipe to drain the waste liquid and then close the drain pipe valve. Next, pour clean water into the passivation chamber through the water inlet pipe to rinse the surface of the wire bundle with strong acid. Then, open the drain pipe valve again to drain the waste liquid and then close the drain pipe valve. Next, pour a saturated Ca(OH)2 solution with pH=12.5 into the water inlet pipe, close the water inlet pipe valve, and begin passivating the wire bundle electrode. After 6-8 days, open the drain valve to discharge the waste liquid. After the waste liquid is discharged, close the drain valve. Open the inlet valve, pour in the ethanol solution, and clean the saturated Ca(OH)2 solution from the surface of the fiber bundle. Open the drain valve to discharge the waste liquid. Turn on the fan. After the surface of the fiber bundle dries, the passivation process is complete.

4. The method for preparing a wire bundle electrode with coupled stress as described in claim 1, characterized in that, The filaments are made of carbon steel, with a diameter of 3-5 mm and a length of 15-20 cm.

5. The method for fabricating a wire bundle electrode with coupled stress as described in claim 1, characterized in that, The integrated device for fabricating coupled stress wire bundle electrodes also includes two support rods, which are arranged in parallel on both sides of the lead screw. One end of each support rod is fixed to the support plate, and the other end is fixed to the support block. The support rods are arranged in parallel with the lead screw, and the support rods pass through the nut seat.

6. The method for fabricating a wire bundle electrode with coupled stress as described in claim 1, characterized in that, The first fixing plate and the second fixing plate have multiple mounting holes on their walls. Prestressed locking plates are installed in the mounting holes, and the wire bundle is fixed on the prestressed locking plates.

7. The method for fabricating a wire bundle electrode with coupled stress as described in claim 1, characterized in that, A fan is installed inside the box cover.

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