Cement-based material accelerated dissolution experimental system and experimental method

Abstract

This invention discloses an accelerated corrosion experimental system and method for cement-based materials. The system includes: a circulating water supply module for providing a corrosion solution with controllable flow rate and temperature and promptly removing dissolved ions; a real-time corrosion detection module for real-time monitoring of the pH of the corrosion solution, the content of dissolved calcium ions, and the mass loss of the specimen; a real-time environmental detection module for monitoring the water flow velocity and temperature scouring the specimen surface to maintain a stable corrosion environment; and a data acquisition system for connecting the corrosion and environmental real-time detection modules and collecting experimental data. This invention solves the problem of uneven dissolution along all directions of the specimen in traditional electro-accelerated corrosion, which makes it difficult to characterize the macroscopic properties of the specimen, such as mechanical properties, after corrosion. Furthermore, by combining this with the real-world water scouring environment in engineering applications, it reduces the enrichment and precipitation of calcium ions at the cathode, enabling comprehensive real-time evaluation of the calcium corrosion characteristics of cement-based materials under various environments, including electro-acceleration, water scouring, and their coupling.

Description

Technical Field

[0001] This invention relates to the field of concrete durability performance testing and evaluation technology; specifically, it relates to an accelerated corrosion test system and test method for cement-based materials. Background Technology

[0002] Calcium dissolution refers to the process by which calcium in cement-based materials is continuously dissolved due to the concentration difference between the surface and the groundwater, resulting in changes in the microstructure of the cement-based materials and a decrease in their mechanical properties and bonding ability.

[0003] Research on calcium dissolution in concrete started relatively late, but has developed rapidly. Because the calcium dissolution process in ambient water is slow, it is not conducive to the study of long-term specimen performance. Currently, researchers mostly use deionized water immersion, chemical solution immersion, and electro-acceleration to speed up dissolution, but many problems remain. For example, deionized water immersion is slow, takes a long time, and has poor accelerated dissolution effect; chemical solution immersion causes significant pollution, is costly, and poses safety risks when storing reagents (ammonium nitrate).

[0004] Electrically accelerated dissolution can effectively avoid the above two situations. However, traditional electrical acceleration uses sheet-like specimens to dissolve in a single direction, resulting in uneven dissolution progress in different directions. This makes it impossible to accurately assess the mechanical and other macroscopic properties of the specimen after dissolution, severely limiting the widespread application of electrical accelerated dissolution. On the other hand, when specimens are placed statically in water using traditional electrical acceleration methods, the dissolved calcium ions cannot be carried away in time. This is inconsistent with the actual engineering environment and can lead to the accumulation of Ca(OH)2 or CaCO3 (derived from the carbonization of Ca(OH)2) on the cathode specimen surface, causing blockage and inaccurate results over long periods. In addition, the actual service conditions of concrete are often accompanied by water flow erosion at different velocities, which exacerbates calcium dissolution and has not been considered in traditional dissolution detection. Summary of the Invention

[0005] To address the problems of the prior art, this invention provides an accelerated dissolution test system and method for cement-based materials, aiming to solve the problems of uneven dissolution in all directions of electrically accelerated dissolution specimens, inaccurate long-term results, and inconsistency with actual water flow scouring environments. This enables rapid, real-time, and comprehensive testing of the dissolution performance of concrete under different environments.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] The features of the accelerated dissolution experimental system for cement-based materials of this invention include: an electro-accelerated dissolution module, a circulating water supply module, a real-time dissolution detection module, a real-time environmental control module, and a data acquisition module, wherein:

[0008] The electro-accelerated etching module is used to provide the electric field required for accelerated etching of the specimen, and includes: a regulated DC power supply for adjusting the voltage of the accelerating electric field, the positive terminal of which is connected to the anode metal rod through a wire, and the negative terminal of which is connected to the annular cathode through a wire.

[0009] The circulating water supply module is used to provide a solvent with controllable flow rate and temperature and to remove dissolved ions, and includes: a constant temperature system, a cathode water circulation module and an anode water circulation module;

[0010] The constant temperature system is used to provide the constant temperature water required for dissolution;

[0011] The cathode circulating water module is used to provide cathode circulating water and erode the surface of the specimen, and includes: a cathode constant temperature water supply tank, a stirrer connected to the cathode constant temperature water supply tank for preparing a mixed etching solution, the outlet of the cathode constant temperature water supply tank being connected to the inlet of the cathode water pump, and the outlet of the cathode water pump being connected to the inlet of the etching test chamber; the inlet of the cathode constant temperature water supply tank being connected to the outlet of the etching test chamber.

[0012] The anode circulating water module is used to provide anode circulating water and includes: an anode constant temperature water supply tank, the outlet of which is connected to the inlet of the anode water pump, the outlet of which is connected to the inlet of the flow guide shroud; and the inlet of the anode constant temperature water supply tank is connected to a hole in the specimen.

[0013] The real-time corrosion detection module is used for real-time detection of pH, dissolved calcium ion content, specimen mass loss, and corrosion fluid renewal during the corrosion process. It includes: a pressure sensor placed at the bottom of the specimen, a calcium ion sensor placed in the cathode constant temperature water supply tank, and pH detection devices placed in the cathode constant temperature water supply tank and the anode constant temperature water supply tank, respectively.

[0014] The real-time environmental monitoring module is used to monitor the flow rate and temperature of water flowing onto the surface of the specimen in order to maintain the stability of the corrosion environment, and includes: a speed monitoring device and a temperature monitoring device installed in the outlet circulating water pipe of the corrosion test chamber.

[0015] The data acquisition module is connected to the speed detection device, temperature detection device, pressure sensor, calcium ion sensor, and pH detection device via cables to collect experimental data and interact with the control terminal with a display screen via a communication module.

[0016] The experimental method of the present invention based on the aforementioned accelerated dissolution experimental system for cement-based materials is characterized by comprising the following steps:

[0017] Step 1) Set the specimen into a hollow ring shape and place an anode metal rod in the middle. Place the specimen in the slot of the corrosion test chamber and connect the top of the specimen to the flow guide shroud.

[0018] Step 2) Turn on the constant temperature system to keep the temperature of the etching solution or deionized water constant, and fill the cathode constant temperature water supply tank and anode constant temperature water supply tank with deionized water. If the etching solution is a mixture of mud and sand, treat the mud and sand in advance and place it in the cathode water supply tank and turn on the stirrer.

[0019] Step 3) Turn on the cathode water pump and anode water pump and adjust them to the predetermined flow rate. Monitor the corrosion environment of the specimen using the flow rate detection device and temperature detection device.

[0020] Step 4) Set the etching voltage and etching time, start the electro-accelerated etching module, and select electro-acceleration, water flow scouring or a combination of both according to the testing requirements to etch the specimen;

[0021] Step 5) Use a pressure sensor to detect the weight loss of the specimen during the etching process in real time, a calcium ion sensor to detect the dissolved calcium ions in real time, and a pH detection device to monitor the pH value of the etching solution in the cathode constant temperature water supply tank and the anode constant temperature water supply tank.

[0022] Step 6) The data acquisition module collects data from each sensor in real time to guide environmental monitoring and calculation of dissolution kinetics at different ages;

[0023] Step 7) After the dissolution is completed, the specimen is taken out and its mechanical properties, dissolution depth, surface morphology, chemical composition and microstructure are tested to obtain the relationship between dissolution kinetics and the macroscopic and microscopic properties of cement-based materials, and to serve as the basis for the dissolution resistance of cement-based materials.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. This invention sets up a reasonable accelerating electric field and specimen shape, achieving radial uniform dissolution of the specimen. This changes the problem of uneven dissolution in all directions and difficulty in detecting macroscopic properties of traditional flat plate specimens. It ensures that macroscopic data such as mechanical properties are referable and can serve as an important basis for rapid laboratory evaluation of corrosion resistance and prediction of engineering life.

[0026] 2. The present invention incorporates a circulating water supply module, which breaks the limitation of traditional calcium dissolution that does not consider the acceleration of dissolution by water flow. Furthermore, the flowing circulating water promptly removes the dissolved calcium ions, thus improving the problem of inaccurate long-term dissolution data caused by surface blockage due to cathode calcium enrichment.

[0027] 3. This invention includes a real-time corrosion detection module and a real-time environmental control module, which can monitor the corrosion reaction environment and leaching-related data in real time, thereby further improving the accuracy of the experiment, the realism of the simulation, and the reliability of the data.

[0028] 4. The present invention also includes a data acquisition module, which simplifies the process of detecting environmental data and collecting experimental data.

[0029] 5. This invention breaks through the limitations of traditional electro-acceleration methods, closely integrates electro-acceleration with the determination of other macroscopic properties, and places it in a real water flow scouring environment. It can also avoid the influence of cathode deposits on experimental results. It is highly practical and operable, and because of its broad application prospects, it is very suitable for large-scale promotion and application. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the experimental system of the present invention;

[0031] Figure 2 This is a schematic diagram of the arrangement of the water outlet at the bottom of the corrosion test chamber of the present invention;

[0032] Numbers in the diagram: 1-Cathode constant temperature water supply tank, 2-Agitator, 3-Water pump, 4-Anode constant temperature water supply tank, 5-Stabilized DC power supply, 6-Anode, 7-Cathode, 8-Dissolution test chamber, 9-Flow guide shroud, 10-Specimen, 11-Velocity detection device, 12-Temperature detection device, 13-Pressure sensor, 14-Calcium ion sensor, 15-pH value detection device. Detailed Implementation

[0033] To address the problems mentioned in the background section regarding electrically accelerated dissolution, such as uneven dissolution in different directions of traditional specimens, accumulation and precipitation of dissolved calcium ions at the cathode, and insufficient research on the impact of water flow erosion on dissolution, this invention proposes an experimental system for accelerating calcium dissolution in cement-based materials. Figure 1 As shown, the accelerated dissolution experimental system for cement-based materials includes: a cathode constant-temperature water supply tank 1, a stirrer 2, a water pump 3, an anode constant-temperature water supply tank 4, a regulated DC power supply 5, an anode 6, a cathode 7, a dissolution test chamber 8, a flow guide 9, a specimen 10, a velocity detection device 11, a temperature detection device 12, a pressure sensor 13, a calcium ion sensor 14, and a pH value detection device 15, which respectively belong to the electro-accelerated dissolution module, the circulating water supply module, the real-time dissolution detection module, the real-time environmental control module, and the data acquisition module.

[0034] An electro-accelerated etching module is used to provide the electric field required for accelerated etching of the specimen, and includes: a regulated DC power supply 5 for adjusting the voltage of the accelerating electric field, the positive terminal of which is connected to the anode metal rod 6 through a wire, and the negative terminal of which is connected to the annular cathode 7 through a wire;

[0035] As a preferred option, a stainless steel ring plate is selected as the cathode and arranged inside the corrosion test chamber, and a titanium alloy anode metal rod is selected as the anode.

[0036] Preferably, the regulated DC power supply voltage is adjustable within the range of 10-60V.

[0037] The circulating water supply module is used to provide a solvent with controllable flow rate and temperature and to remove dissolved ions, and includes: a constant temperature system, a cathode water circulation module and an anode water circulation module;

[0038] The temperature control system is used to provide the constant temperature water required for dissolution;

[0039] The cathode circulating water module is used to provide cathode circulating water and erode the surface of the specimen, and includes: a cathode constant temperature water supply tank 1, a stirrer 2 connected to the cathode constant temperature water supply tank 1 for preparing a mixed etching solution, the outlet of the cathode constant temperature water supply tank 1 being connected to the inlet of the cathode water pump 3a, the outlet of the cathode water pump 3a being connected to the inlet of the etching test chamber 8; and the inlet of the cathode constant temperature water supply tank 1 being connected to the outlet of the etching test chamber 8.

[0040] The anode circulating water module is used to provide anode circulating water and includes: an anode constant temperature water supply tank 4, the outlet of the anode constant temperature water supply tank 4 is connected to the inlet of the anode water pump 3b, the outlet of the anode water pump 3b is connected to the inlet of the guide shroud 9; and the inlet of the anode constant temperature water supply tank 4 is connected to a hole in the specimen 10.

[0041] As a preferred option, a variable speed pump is selected to simulate the scouring effect of different flow velocities;

[0042] As a preferred option, a non-metallic, non-conductive guide shroud is selected and connected to the top of the specimen by screws to reduce the impact of water flow on the top of the specimen, guide the direction of water flow and ensure stable flow velocity. The top of the guide shroud has an opening to connect the anode circulating water pipe and the anode metal rod, and the opening is sealed with epoxy resin.

[0043] As a preferred embodiment, to ensure a constant water flow velocity at the bottom of the specimen, four outlets are arranged along different directions of the circular dissolution test chamber, and connected to the cathode circulating water pipe via a four-way pipe, such as... Figure 2 As shown, ①, ②, ③, and ④ are the four water outlets arranged at the bottom of the corrosion test chamber.

[0044] like Figure 2 As shown, the real-time corrosion detection module is used for real-time detection of pH, dissolved calcium ion content, specimen mass loss and refresh of the corrosion solution during the corrosion process, and includes: a pressure sensor 13 placed at the bottom of the specimen, a calcium ion sensor 14 placed in the cathode constant temperature water supply tank 1, and a pH value detection device 15 placed in the cathode constant temperature water supply tank 1 and the anode constant temperature water supply tank 4 respectively.

[0045] Preferably, the pressure sensor is arranged at the bottom of the specimen and in the slot at the bottom of the corrosion test chamber to detect changes in the specimen's mass during the corrosion process.

[0046] The real-time environmental monitoring module is used to monitor the flow rate and temperature of water flowing on the surface of the specimen 10 in order to maintain the stability of the corrosion environment. It includes a velocity detection device 11 and a temperature detection device 12 installed in the outlet circulating water pipe of the corrosion test chamber 8.

[0047] The data acquisition module is connected to the speed detection device 11, temperature detection device 12, pressure sensor 13, calcium ion sensor 14, and pH detection device 15 via cables to collect experimental data and interact with the control terminal with a display screen via the communication module.

[0048] In this embodiment, an experimental method for an accelerated dissolution experimental system for cement-based materials includes the following steps:

[0049] Step 1: Set the specimen 10 into an annular hollow shape and set the anode metal rod 6 in the middle. Place the specimen 10 in the slot of the corrosion test chamber 8 and connect the top of the specimen 10 to the flow guide shroud.

[0050] As a preferred option, the specimen size is different from that of traditional specimens. It should be made into a hollow ring with a size of φ100mm×200mm and a central hole size of φ10mm×200mm. An anode metal rod is arranged in the middle of the specimen, and a cathode stainless steel ring is arranged around the specimen, so that the specimen is radially etched under the action of an electric field, and the ring specimen is etched uniformly in all directions.

[0051] Step 2: Turn on the constant temperature system to keep the temperature of the etching solution or deionized water constant, and fill the cathode constant temperature water supply tank 1 and the anode constant temperature water supply tank 4 with deionized water. If the etching solution is a mixture of mud and sand, treat the mud and sand in advance and place it in the cathode water supply tank 1 and turn on the stirrer.

[0052] As a preferred option, a constant temperature environment is a prerequisite for the comparability of experimental results, and its selection can be determined according to the actual service environment of the project.

[0053] As a preferred option, when using a mixture of mud and sand as the solvent, the mud and sand content and fineness can be set according to the actual conditions of the water area. Pre-treatment of the mud and sand aims to reduce harmful ions in the mud and sand and their impact on pH value. The mud and sand need to be rinsed multiple times with deionized water until the rinsing solution is neutral.

[0054] Step 3: Turn on the cathode water pump 3a and the anode water pump 3b and adjust them to the predetermined flow rate. Monitor the corrosion environment of the specimen 10 through the flow rate detection device 11 and the temperature detection device 12.

[0055] As a preferred option, the flow velocity can be determined based on the water environment of the project.

[0056] Step 4: Set the etching voltage and etching time, start the electro-accelerated etching module, and select electro-acceleration, water flow scouring or a combination of both according to the testing requirements to etch the specimen;

[0057] As a preferred option, the voltage is selected based on the dissolution mode. If the flowing water environment is not considered, the voltage is selected as 30-60V. If the current scouring and electro-acceleration coupling effects are considered, the voltage is selected as 10-30V.

[0058] Step 5: Use pressure sensor 13 to detect the weight loss of specimen 10 in real time during the etching process, calcium ion sensor 14 to detect the dissolved calcium ions in real time, and pH detection device 15 to monitor the pH value of the etching solution in cathode constant temperature water supply tank 1 and anode constant temperature water supply tank 4.

[0059] Preferably, the cathode circulating water should be replaced when the pH of the cathode circulating water is greater than 12.5.

[0060] Step 6: The data acquisition module collects data from each sensor in real time to guide environmental monitoring and calculation of dissolution kinetics at different ages;

[0061] Step 7: After the dissolution is completed, take out specimen 10 and test its mechanical properties, dissolution depth, surface morphology, chemical composition and microstructure, so as to obtain the relationship between dissolution kinetics and the macroscopic and microscopic properties of cement-based materials, and use it as the basis for the dissolution resistance of cement-based materials.

[0062] As a preferred method, the mechanical properties were tested in accordance with GB / T50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete". The erosion depth was detected by phenolphthalein titration. The appearance morphology was determined by observation and binocular microscopy. The chemical composition was detected by thermogravimetric analysis and X-ray diffraction analysis in the eroded and non-eroded areas respectively. The microstructure was detected by scanning electron microscopy and mercury porosimetry.

[0063] As a preferred approach, by combining the changes in macroscopic and microscopic properties of the specimen before and after dissolution, and the changes in pH values ​​of the anode and cathode, the amount of calcium ion dissolution, and the amount of specimen mass loss detected in real time during the dissolution process, the dissolution kinetic data of the specimen can be calculated, and the relationship between dissolution behavior and concrete performance can be established.

[0064] Example:

[0065] Taking laboratory-made concrete as an example, its mix proportions are shown in Table 1:

[0066] Table 1. Mix proportions of laboratory-made concrete

[0067] Serial Number cement fly ash Mineral powder sand stone W / C Water reducing agent 1 450 0 0 723 1040 0.31 1.4％ 2 270 135 45 723 1040 0.31 1.4％ 3 135 135 180 723 1040 0.31 1.4％ 4 450 0 0 723 1040 0.40 1.2％ 5 270 135 45 723 1040 0.40 1.2％ 6 135 135 180 723 1040 0.40 1.2％ 7 450 0 0 723 1040 0.50 1.0％ 8 270 135 45 723 1040 0.50 1.0％ 9 135 135 180 723 1040 050 10％

[0068] Concrete specimens (φ100mm×200mm) with an internal central hole were molded. Before the dissolution process began, the axial compressive strength, oven-dry weight, chemical composition of the slurry, and microstructure of the specimens were measured.

[0069] The specimen is placed in the bottom slot of the corrosion test chamber and fixed. All components are connected and adjusted to ensure that each component can work normally and be effectively controlled.

[0070] Based on the actual service environment of the project in the Yangtze River basin, the experimental constant temperature environment was determined to be 20℃, the water flow velocity to be 1.5m / s, and the sediment content to be 40mg / L. An accelerating voltage of 30V was determined to ensure the ion transport rate.

[0071] Start the constant temperature system and inject constant temperature deionized water into the water supply tank after the temperature is constant. If the influence of silt is considered, add silt into the cathode constant temperature water supply tank and start the agitator at the same time to stir the etch solution in advance and test the silt content and uniformity at the outlet.

[0072] The water pump is adjusted according to the set water flow rate to start accelerating the dissolution of the specimen. During the dissolution process, the calcium ion content, pH value, specimen mass loss, water flow rate and temperature in the dissolution solution are detected and collected in real time through the real-time dissolution detection module and the real-time environmental control module.

[0073] The etching time was set to 28 days according to the test requirements. After etching, the surface morphology changes of the specimen were recorded. The cylindrical specimen was cut along its cross-section, and the etching depth was determined using the phenolphthalein method. The compressive strength of the etched specimen was determined according to GB / T50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete". The mineral composition and microstructure of the specimen were tested using XRD, TG, SEM and other methods. All of the above are existing technologies and will not be described in detail in this embodiment.

[0074] Based on the calcium ion content, pH value, and dissolution depth data detected during the dissolution process, dissolution kinetics calculations were performed. Combined with the differences in macroscopic properties and microstructure of the specimens before and after dissolution, the dissolution resistance of cement-based materials was assessed, and the impact on the service life of the project was predicted.

[0075] This invention discloses an accelerated dissolution experimental system and method for cement-based materials. It not only allows for the determination of the dissolution amount of cement-based materials under specific environmental conditions (flow rate, temperature, sediment, and electric field), but also overcomes the inaccuracies in macroscopic performance studies and long-term monitoring results caused by calcium ion enrichment in traditional electro-accelerated dissolution methods. Compared with existing technologies, this invention represents a significant technological advancement, possessing prominent substantive features and remarkable progress.

[0076] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All modifications made based on the design principles of the present invention, and modifications made without creative effort, should fall within the scope of protection of the present invention.

Claims

1. An experimental system for accelerating the dissolution of cement-based materials, characterized in that, include: The system includes an electro-accelerated dissolution module, a circulating water supply module, a real-time dissolution detection module, a real-time environmental control module, and a data acquisition module, among which: The electro-accelerated etching module is used to provide the electric field required for accelerated etching of the specimen, and includes: a regulated DC power supply (5) for adjusting the voltage of the accelerating electric field, the positive terminal of which is connected to the anode metal rod (6) through a wire, and the negative terminal of which is connected to the annular cathode (7) through a wire; the specimen is made into an annular hollow specimen, the anode metal rod is arranged in the middle of the specimen, and the cathode stainless steel ring is arranged around the specimen, so that the specimen is etched radially under the action of the electric field, and the annular specimen is etched uniformly in all directions; The circulating water supply module is used to provide a solvent with controllable flow rate and temperature and to remove dissolved ions, and includes: a constant temperature system, a cathode circulating water module and an anode circulating water module; The constant temperature system is used to provide the constant temperature water required for dissolution; The cathode circulating water module is used to provide cathode circulating water and erode the surface of the specimen, and includes: a cathode constant temperature water supply tank (1), a stirrer (2) connected to the cathode constant temperature water supply tank (1) for preparing a mixed etchant, the outlet of the cathode constant temperature water supply tank (1) is connected to the inlet of the cathode water pump (3a), the outlet of the cathode water pump (3a) is connected to the inlet of the etchant test chamber (8); the inlet of the cathode constant temperature water supply tank (1) is connected to the outlet of the etchant test chamber (8); The anode circulating water module is used to provide anode circulating water and includes: an anode constant temperature water supply tank (4), the outlet of the anode constant temperature water supply tank (4) is connected to the inlet of the anode water pump (3b), the outlet of the anode water pump (3b) is connected to the inlet of the guide shroud (9); the inlet of the anode constant temperature water supply tank (4) is connected to the hole in the specimen (10); The real-time corrosion detection module is used for real-time detection of pH, dissolved calcium ion content, specimen mass loss and replacement of the corrosion solution during the corrosion process, and includes: a pressure sensor (13) placed at the bottom of the specimen, a calcium ion sensor (14) placed in the cathode constant temperature water supply tank (1), and a pH detection device (15) placed in the cathode constant temperature water supply tank (1) and the anode constant temperature water supply tank (4) respectively. The real-time environmental detection module is used to detect the flow rate and temperature of water flowing on the surface of the specimen (10) in order to maintain the stability of the corrosion environment, and includes: a speed detection device (11) and a temperature detection device (12) installed in the outlet circulating water pipe of the corrosion test chamber (8). The data acquisition module is connected to the speed detection device (11), temperature detection device (12), pressure sensor (13), calcium ion sensor (14), and pH detection device (15) via cables to collect experimental data and interact with the control terminal with a display screen via the communication module.

2. An experimental method based on the accelerated dissolution experimental system for cement-based materials as described in claim 1, characterized in that, Includes the following steps: Step 1) Place the specimen (10) in the slot of the corrosion test chamber (8), and connect the top of the specimen (10) to the flow guide shroud; Step 2) Turn on the constant temperature system to control the temperature of the etching solution or deionized water to be constant, and fill the cathode constant temperature water supply tank (1) and anode constant temperature water supply tank (4) with deionized water. If the etching solution is a mixture of mud and sand, treat the mud and sand in advance and place it in the cathode water supply tank (1) and turn on the stirrer. Step 3) Turn on the cathode water pump (3a) and anode water pump (3b) and adjust them to the predetermined flow rate. Monitor the corrosion environment of the specimen (10) using the flow rate detection device (11) and the temperature detection device (12). Step 4) Set the etching voltage and etching time, start the electro-accelerated etching module, and select electro-acceleration, water flow scouring or a combination of both according to the testing requirements to etch the specimen; Step 5) Use pressure sensor (13) to detect the weight loss of specimen (10) in real time during the etching process, calcium ion sensor (14) to detect the dissolved calcium ions in real time, and pH detection device (15) to monitor the pH value of the etching solution in cathode constant temperature water supply tank (1) and anode constant temperature water supply tank (4). Step 6) The data acquisition module collects data from each sensor in real time to guide environmental monitoring and calculation of dissolution kinetics at different ages; Step 7) After the dissolution is completed, the specimen (10) is taken out and its mechanical properties, dissolution depth, appearance morphology, chemical composition and microstructure are tested to obtain the relationship between dissolution kinetics and the macroscopic and microscopic properties of cement-based materials, and to serve as the basis for the anti-dissolution performance of cement-based materials.

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