A reinforced concrete corrosion system based on coupling of carbonation and chloride salt attack

Abstract

The utility model discloses a reinforced concrete corrosion system based on carbonization and chloride salt erosion coupling action, wherein, gas distribution pipe network includes main gas pipe, and the even distribution of a plurality of branch gas pipes is arranged on main gas pipe, and the tail end of each branch gas pipe is installed with micropore diffuser. Liquid circulation pipeline includes main liquid pipe, and main liquid pipe includes two vertical sections and the horizontal section of connecting two vertical sections, and the bottom of two vertical sections of main liquid pipe is linked with liquid storage tank respectively, and is installed with circulating pump on main liquid pipe, and is provided with a plurality of branch liquid pipes on the horizontal section of main liquid pipe, and is installed with an atomizing nozzle on each branch liquid pipe, and atomizing nozzle is located above liquid storage tank, and forms liquid circulation loop. The utility model has realized the even distribution and controllable supply of carbon dioxide gas and chloride salt solution in the box, has effectively simulated the corrosion environment under the cooperation of carbonization and chloride salt, and has solved the technical problem of single environment simulation of reinforced concrete corrosion system in the prior art.

Description

Technical Field

[0001] This utility model belongs to the field of reinforced concrete technology and relates to concrete durability testing, specifically to a reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt erosion. Background Technology

[0002] Reinforced concrete structures, under complex conditions such as marine environments and saline-alkali areas, are subjected to the coupled effects of carbonation and chloride corrosion over long periods, leading to a significant acceleration in steel corrosion rates and a sharp decline in structural durability. However, existing steel corrosion simulation devices face significant technical bottlenecks in terms of environmental simulation, monitoring accuracy, and specimen compatibility.

[0003] Traditional corrosion systems typically conduct accelerated testing targeting only a single factor, failing to simultaneously regulate the interactive effects of carbonation-induced concrete neutralization and chloride ion penetration. Experiments have shown that carbonation can... The diffusion coefficient increases by 3 to 5 times, leading to a serious disconnect between the results and actual engineering conditions. Meanwhile, existing monitoring methods mostly rely on destructive sampling or single electrochemical parameters, making it difficult to capture the pH inside concrete in real time. The spatiotemporal evolution of concentration gradient and humidity distribution makes the corrosion risk assessment inaccurate; furthermore, traditional enclosures only support standard 100×100×400 mm test blocks, making it difficult to accommodate multi-scale components such as steel mesh or small beams and columns, resulting in a gap in the study of corrosion mechanisms at the material and component levels. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a reinforced concrete corrosion system based on the coupled effect of carbonization and chloride salt corrosion, thereby solving the technical problem of the limited environmental simulation in existing reinforced concrete corrosion systems.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A corrosion system for reinforced concrete based on the coupling effect of carbonization and chloride salt corrosion is disclosed. The system includes a sealed enclosure, which comprises a double-layer sealed enclosure body. A coupled corrosion environment unit is installed inside the sealed enclosure, which includes a gas distribution pipeline network and a liquid circulation pipeline.

[0006] A liquid storage tank is provided at the bottom of the double-layer sealed box body. The gas distribution network includes a main gas pipe, on which multiple branch gas pipes are evenly distributed, and each branch gas pipe is equipped with a microporous diffuser at its end.

[0007] The liquid circulation pipeline includes a main liquid pipe, which comprises two vertical sections and a horizontal section connecting the two vertical sections. The bottom ends of the two vertical sections of the main liquid pipe are respectively connected to the liquid storage tank. A circulation pump is installed on the main liquid pipe. Multiple branch liquid pipes are provided on the horizontal section of the main liquid pipe, and an atomizing nozzle is installed on each branch liquid pipe. The atomizing nozzle is located above the liquid storage tank, forming a liquid circulation loop.

[0008] This utility model also has the following technical features: The main gas pipe is connected to the carbon dioxide gas source pipe outside the sealed box through a solenoid valve; the distance between two adjacent branch gas pipes is 15cm to 20cm, and the pore diameter of the microporous diffuser is 0.1mm to 0.2mm.

[0009] A flow meter is also installed on the main liquid pipe; the spray angle of the atomizing nozzle is 60° to 90°.

[0010] The bottom of the liquid storage tank is equipped with a heating coil.

[0011] The inner wall of the double-sealed enclosure is coated with an anti-corrosion coating, and a temperature and humidity sensor and a dehumidifier are installed inside the double-sealed enclosure.

[0012] The top of the double-layer sealed box body is also provided with a sealed door, and the side wall of the double-layer sealed box body is provided with an observation window.

[0013] The double-layer sealed box body is also provided with a specimen fitting unit. The specimen fitting unit includes a base, which is located above the liquid storage tank. The two sides of the base are fixedly installed on the inner wall of the double-layer sealed box body. Liquid return channels are provided between the other two sides of the base and the inner wall of the double-layer sealed box body. The base is provided with through holes for the two vertical sections of the main liquid pipe to pass through.

[0014] The base is provided with a specimen stage, and the specimen stage is provided with an independent specimen support frame and a steel mesh fixing frame; the microporous diffuser is located on one side of the specimen support frame and the steel mesh fixing frame; the atomizing nozzle is located above the specimen support frame and the steel mesh fixing frame.

[0015] A vertical support rod is fixedly installed on the base, and a horizontal support rod with adjustable height is installed on the vertical support rod; a specimen indenter is set on the horizontal support rod, and the specimen indenter is located directly above the specimen support frame.

[0016] The vertical support rod has multiple height positioning pin holes, and the horizontal support rod also has a positioning hole on one side. The cooperation of the height positioning pin holes, positioning holes and positioning pins allows the horizontal support rod to be installed on the vertical support rod to achieve height adjustment.

[0017] Compared with the prior art, this utility model has the following technical effects: (I) The system of this utility model achieves uniform distribution and controllable supply of carbon dioxide gas and chloride salt solution in the tank through the coordinated design of gas distribution pipeline and liquid circulation pipeline, effectively simulating the corrosion environment under the synergistic effect of carbonization and chloride salt, and solving the technical problem of the single environment simulation of reinforced concrete corrosion system in the prior art.

[0018] (II) The specimen adaptation unit of this utility model enables the system to adapt to concrete specimens of different sizes and types, realize the study of corrosion behavior from the material to the component level, and solve the problem of poor multi-scale adaptability of traditional experimental boxes. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt erosion.

[0020] Figure 2 This is a structural schematic diagram of a coupled corrosion environment unit.

[0021] Figure 3 This is a schematic diagram of the structure of the test specimen adapter unit.

[0022] The meanings of the labels in the figure are as follows: 1-Sealed box, 2-Gas distribution network, 3-Liquid circulation pipeline, 4-Specimen fitting unit.

[0023] 101-Double-layer sealed main body, 102-Liquid storage tank, 103-Heating coil, 104-Temperature and humidity sensor, 105-Dehumidifier, 106-Sealed door, 107-Observation window.

[0024] 201-Main air pipe, 202-Branch air pipe, 203-Microporous diffuser, 204-Solenoid valve, 205-Carbon dioxide gas source pipe.

[0025] 301-Main liquid pipe, 302-Circulation pump, 303-Branch liquid pipe, 304-Atomizing nozzle, 305-Flow meter.

[0026] 401-Base, 402-Liquid reflux channel, 403-Through hole, 404-Specimen stage, 405-Specimen support frame, 406-Reinforcing mesh fixing frame, 407-Vertical support rod, 408-Horizontal support rod, 409-Specimen pressure head, 410-Height positioning pin hole.

[0027] The specific content of this utility model will be further explained in detail below with reference to the embodiments. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, all materials, equipment and components in this utility model are made from materials, equipment and components known in the prior art.

[0029] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0030] Example: This embodiment presents a reinforced concrete corrosion system based on the coupled effect of carbonation and chloride salt corrosion, such as... Figure 1 As shown, the system includes a sealed enclosure 1, which includes a double-layer sealed enclosure body 101. A coupled corrosion environment unit is installed inside the sealed enclosure 1. The coupled corrosion environment unit includes a gas distribution pipeline network 2 and a liquid circulation pipeline 3.

[0031] like Figure 1 As shown, a liquid storage tank 102 is provided at the bottom of the double-layer sealed box body 101.

[0032] like Figure 2 As shown, the gas distribution network 2 includes a main gas pipe 201, and multiple branch gas pipes 202 are evenly distributed on the main gas pipe 201. A microporous diffuser 203 is installed at the end of each branch gas pipe 202.

[0033] like Figure 2 As shown, the liquid circulation pipeline 3 includes a main liquid pipe 301, which includes two vertical sections and a horizontal section connecting the two vertical sections. The bottom ends of the two vertical sections of the main liquid pipe 301 are respectively connected to the liquid storage tank 102. A circulation pump 302 is installed on the main liquid pipe 301. Multiple branch liquid pipes 303 are provided on the horizontal section of the main liquid pipe 301, and an atomizing nozzle 304 is installed on each branch liquid pipe 303. The atomizing nozzle 304 is located above the liquid storage tank 102, forming a liquid circulation loop.

[0034] As a preferred embodiment of this invention, such as Figure 2 As shown, the main air pipe 201 is connected to the carbon dioxide gas source pipe 205 outside the sealed box 1 through the solenoid valve 204; the distance between two adjacent branch air pipes 202 is 15cm to 20cm, and the aperture of the microporous diffuser 203 is 0.1mm to 0.2mm.

[0035] As a preferred embodiment of this invention, such as Figure 2 As shown, a flow meter 305 is also installed on the main liquid pipe 301; the spray angle of the atomizing nozzle 304 is 60° to 90°.

[0036] As a preferred embodiment of this invention, such as Figure 1As shown, a heating coil 103 is provided at the bottom of the liquid storage tank 102. In this embodiment, the heating power of the heating coil 103 is 400W-2000W, and the temperature control accuracy is ±0.5℃.

[0037] As a preferred embodiment of this invention, such as Figure 1 As shown, the inner wall of the double-layer sealed enclosure 101 is provided with an anti-corrosion coating, and a temperature and humidity sensor 104 and a dehumidifier 105 are installed inside the double-layer sealed enclosure 101. In this embodiment, both the temperature and humidity sensor 104 and the dehumidifier 105 are commonly used temperature and humidity sensors and dehumidifiers known in the art.

[0038] As a preferred embodiment of this invention, such as Figure 1 As shown, a sealing door 106 is provided on the top of the double-layer sealed box body 101, and an observation window 107 is provided on the side wall of the double-layer sealed box body 101.

[0039] As a further solution in this embodiment, such as Figure 1 As shown, the double-layer sealed box body 101 is also equipped with a specimen fitting unit 4, such as... Figure 3 As shown, the specimen adapter unit 4 includes a base 401, which is located above the liquid storage tank 102. The two sides of the base 401 are fixedly installed on the inner wall of the double-layer sealed box body 101, and the other two sides of the base 401 are provided with liquid return channels 402 between them and the inner wall of the double-layer sealed box body 101. The base 401 is provided with through holes 403 for two vertical sections of the main liquid pipe 301 to pass through.

[0040] As a further solution in this embodiment, such as Figure 3 As shown, a specimen stage 404 is provided on the base 401, and an independent specimen support frame 405 and a reinforcing mesh fixing frame 406 are provided on the specimen stage 404; a microporous diffuser 203 is located on one side of the specimen support frame 405 and the reinforcing mesh fixing frame 406; an atomizing nozzle 304 is located above the specimen support frame 405 and the reinforcing mesh fixing frame 406. In this embodiment, both the specimen support frame 405 and the reinforcing mesh fixing frame 406 are specimen support frames and reinforcing mesh fixing frames known in the art; the load-bearing capacity of the specimen support frame 405 is not less than 100 kg.

[0041] As a further solution in this embodiment, such as Figure 3 As shown, a vertical support rod 407 is vertically fixedly installed on the base 401, and a horizontal support rod 408 with adjustable height is installed on the vertical support rod 407; a specimen indenter 409 is provided on the horizontal support rod 408, and the specimen indenter 409 is located directly above the specimen support frame 405. In this embodiment, the specimen indenter 409 adopts a commonly used specimen indenter in the art, and the specimen indenter is used to press the reinforced concrete specimen to be tested from above.

[0042] As a preferred embodiment of this invention, such as Figure 3 As shown, the vertical support rod 407 has multiple height positioning pin holes 410, and the horizontal support rod 408 also has a positioning hole on one side. The cooperation of the height positioning pin holes 410, the positioning hole, and the positioning pin allows the horizontal support rod 408 to be mounted on the vertical support rod 407 to achieve height adjustment. In this embodiment, the height of the vertical support rod 407 is 40cm to 140cm; the distance between two adjacent height positioning pin holes 406 is 5cm.

[0043] Application Example 1: This application example provides a test method for steel reinforcement corrosion in concrete. This method is based on the reinforced concrete corrosion system described in the above embodiment, which is based on the coupling effect of carbonation and chloride erosion. The method includes the following steps: Check the integrity of the anti-corrosion coating inside the sealed enclosure 1 to ensure it is undamaged. Inject a 3.5wt% NaCl solution into the storage tank 102 and preheat the heating coil 103 to 25°C. Adjust the carbon dioxide gas source using the solenoid valve 204 to stabilize the CO2 concentration inside the enclosure at 20vol%. The microporous diffuser 203 has a pore size of 0.15mm, and the branch gas pipes 202 are spaced 18cm apart.

[0044] Place the reinforced concrete specimen to be tested on the specimen support frame 405 and press it down with the specimen indenter 409.

[0045] The circulation pump 302 is started, driving the liquid circulation flow in the liquid circulation pipeline 3. The atomizing nozzle 304 sprays salt mist towards the center of the chamber at a spray angle of 75°, creating an environment with a humidity of 85%±5%. Simultaneously, the solenoid valve 204 is opened to release CO2 into the chamber. The humidity inside the chamber is maintained at 85%±5% and the temperature at 25℃±1℃ through the heating coil 103, the temperature and humidity sensor 104, and the dehumidifier 105.

[0046] The experiment lasted for 28 days, and the development of corrosion cracks on the surface of the reinforced concrete specimens was observed and recorded periodically through observation window 13. After the experiment, the initial data and real-time monitoring data were compared to analyze the effect of the coupling effect of carbonation and chloride salts on the corrosion rate of the steel bars.

[0047] Application Example 2: This application example presents a test method for steel reinforcement corrosion in concrete. This method is based on the reinforced concrete corrosion system based on the coupling effect of carbonation and chloride erosion described in the above embodiments. The difference between this method and Application Example 1 is as follows: A reinforced concrete beam with dimensions of 200 mm × 300 mm × 1400 mm was fabricated as the reinforced concrete specimen to be tested. The concentration of NaCl solution in the storage tank 102 was increased to 5 wt%, and the heating coil 103 was preheated to 30°C. The CO2 concentration was adjusted to 15 vol.

[0048] The atomizing nozzle 304 sprays salt mist at a 90° angle toward the center of the chamber, forming a vertically downward salt mist spray to simulate the environment of the ocean wave splash zone. The humidity inside the chamber is maintained at 70%±5% and the temperature at 30℃±1℃ by the heating coil 103, temperature and humidity sensor 104, and dehumidifier 105.

[0049] The experiment lasted 60 days. The distribution of corrosion cracks on the sides of the reinforced concrete beams was observed and recorded periodically through observation window 13, with a focus on the rust expansion cracking at the main reinforcement bars. After the experiment, the initial data and real-time monitoring data were compared to analyze the impact of the coupling effect of carbonation and chloride salts on the corrosion rate of the reinforcing bars. The durability degradation pattern of the reinforced concrete beams under the coupling effect of carbonation and chloride salts was evaluated based on the monitoring data.

[0050] Application Example 3: This application example presents a test method for steel reinforcement corrosion in concrete. This method is based on the reinforced concrete corrosion system based on the coupling effect of carbonation and chloride erosion described in the above embodiments. The difference between this method and Application Example 1 is as follows: Steel mesh specimens were prepared as reinforced concrete specimens to be tested. HPB300 steel bars were welded into mesh, and the concrete cover thickness was 15mm (simulating thin-walled components or tunnel lining environment).

[0051] A 2wt% NaCl solution (simulating a shallow groundwater environment in a saline-alkali land) is injected into the storage tank 102, and the preheating temperature of the heating coil 103 is 20℃. The CO2 concentration is adjusted to 10vol% (simulating a moderate carbonization environment) by the solenoid valve 204.

[0052] Use a 406 steel mesh fixing frame to fix the steel mesh specimen, ensuring that the steel mesh specimen is flat and free from deformation.

[0053] The humidity inside the chamber is maintained at 80%±5% and the temperature at 20℃±1℃ by heating coil 103, temperature and humidity sensor 104, and dehumidifier 105, simulating the working conditions of coastal tidal zone with alternating carbonization and chloride salts.

[0054] The experiment lasted 45 days, simulating the erosion effect in actual engineering. Every 7 days, the distribution of rust on the surface of the steel mesh specimen was observed and recorded through observation window 13, with a focus on the degree of rust at the mesh intersections (stress concentration areas). By comparing the differences in rust at different locations on the mesh, the coupling relationship between chloride diffusion path and carbonization depth was verified.

Claims

1. A reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion, the system comprising a sealed enclosure (1), said sealed enclosure (1) comprising a double-layer sealed enclosure body (101), characterized in that, A coupled corrosion environment unit is installed inside the sealed enclosure (1), which includes a gas distribution pipeline (2) and a liquid circulation pipeline (3). The bottom of the double-layer sealed box body (101) is provided with a liquid storage tank (102). The gas distribution network (2) includes a main gas pipe (201), and multiple branch gas pipes (202) are evenly distributed on the main gas pipe (201). Each branch gas pipe (202) is equipped with a microporous diffuser (203) at its end. The liquid circulation pipeline (3) includes a main liquid pipe (301), which includes two vertical sections and a horizontal section connecting the two vertical sections. The bottom ends of the two vertical sections of the main liquid pipe (301) are respectively connected to the liquid storage tank (102). A circulation pump (302) is installed on the main liquid pipe (301). Multiple branch liquid pipes (303) are provided on the horizontal section of the main liquid pipe (301), and an atomizing nozzle (304) is installed on each branch liquid pipe (303). The atomizing nozzle (304) is located above the liquid storage tank (102) to form a liquid circulation loop.

2. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 1, characterized in that, The main gas pipe (201) is connected to the carbon dioxide gas source pipe (205) outside the sealed box (1) through a solenoid valve (204); the distance between two adjacent branch gas pipes (202) is 15cm to 20cm, and the aperture of the microporous diffuser (203) is 0.1mm to 0.2mm.

3. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 1, characterized in that, A flow meter (305) is also installed on the main liquid pipe (301); the spray angle of the atomizing nozzle (304) is 60° to 90°.

4. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 1, characterized in that, The bottom of the liquid storage tank (102) is provided with a heating coil (103).

5. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 1, characterized in that, The inner wall of the double-sealed box body (101) is provided with an anti-corrosion coating, and a temperature and humidity sensor (104) and a dehumidifier (105) are installed inside the double-sealed box body (101).

6. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 1, characterized in that, The top of the double-layer sealed box body (101) is also provided with a sealing door (106), and the side wall of the double-layer sealed box body (101) is provided with an observation window (107).

7. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 1, characterized in that, The double-layer sealed box body (101) is also provided with a specimen fitting unit (4). The specimen fitting unit (4) includes a base (401) located above the liquid storage tank (102). The two sides of the base (401) are fixedly installed on the inner wall of the double-layer sealed box body (101). The other two sides of the base (401) are provided with a liquid return channel (402) between them and the inner wall of the double-layer sealed box body (101). The base (401) is provided with through holes (403) for the two vertical sections of the main liquid pipe (301) to pass through.

8. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 7, characterized in that, The base (401) is provided with a specimen stage (404), and the specimen stage (404) is provided with an independent specimen support frame (405) and a steel mesh fixing frame (406); the microporous diffuser (203) is located on one side of the specimen support frame (405) and the steel mesh fixing frame (406); the atomizing nozzle (304) is located above the specimen support frame (405) and the steel mesh fixing frame (406).

9. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 8, characterized in that, A vertical support rod (407) is fixedly installed on the base (401), and a horizontal support rod (408) with adjustable height is installed on the vertical support rod (407); a specimen indenter (409) is provided on the horizontal support rod (408), and the specimen indenter (409) is located directly above the specimen support frame (405).

10. The reinforced concrete corrosion system based on the coupling effect of carbonation and chloride salt corrosion as described in claim 7, characterized in that, The vertical support rod (407) has multiple height positioning pin holes (410), and the horizontal support rod (408) also has a positioning hole on one side. The cooperation of the height positioning pin holes (410), positioning holes and positioning pins allows the horizontal support rod (408) to be installed on the vertical support rod (407) to achieve height adjustment.

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