Electrochemical protection method for reinforced concrete underground granary

Abstract

The invention belongs to the technical field of civil engineering, and provides an electrochemical protection method for a reinforced concrete underground granary, which comprises the following steps of: continuously arranging auxiliary anodes in a cylinder wall and a bottom plate structure of the underground granary to form a uniform electric field; the periphery of the reinforcement cage is coated with conductive mortar, and an electric continuous system is formed; the anode of an external power supply is connected with the auxiliary anode through a rectifier, and the cathode is connected with a reinforcing mesh of the underground granary to form an impressed current cathodic protection loop; burying a reference electrode in the conductive mortar; the output current and potential are adjusted in real time through an electrochemical protection monitoring and control system, the output current or potential is automatically adjusted according to a preset protection potential range and a current density range, and constant potential or constant current control is carried out; the steel bars are kept in a stable cathodic polarization state through the controllable current, so that electrochemical corrosion of the steel bars is actively inhibited, and long-acting protection of the steel bars in the underground granary structure is achieved.

Description

Technical Field

[0001] This invention belongs to the field of civil engineering technology, specifically an electrochemical protection method for reinforced concrete underground grain silos. Background Technology

[0002] Grain storage is a crucial link in ensuring national food security. Most existing grain warehouses are above-ground structures, but in hot and humid regions such as the Yangtze River Delta, the temperature inside these warehouses often exceeds 30°C due to solar radiation and far-infrared radiation from the ground. Because grain has poor thermal conductivity, even with extensive air conditioning equipment, it is still difficult to achieve uniform temperature control within the warehouse. This not only results in high energy consumption but also leads to increased free fatty acid content in rice, decreased nutritional value and taste, and even grain aging or mold growth (sudden cooling of hot grains easily causes condensation, inducing hydrolysis and mold growth).

[0003] Underground grain silos, leveraging the heat-retaining properties of the soil, can effectively mitigate high summer temperatures, significantly reducing energy consumption and grain loss during storage, while also conserving land resources. This has become an important development direction for national strategic grain reserve facilities. Typical underground grain silos employ a circular reinforced concrete silo structure with a waterproof layer and ventilation openings at the top, and a concrete raft slab at the bottom, maintaining a consistently low-temperature and dry environment inside. However, the underground environment is characterized by high humidity, high salinity, and frequent fluctuations in groundwater levels. The outer walls of the grain silos are often in a state of saturation or alternating wet and dry conditions: chloride ion intrusion and concrete carbonization can damage the passivation film on the steel reinforcement surface, leading to steel corrosion, volume expansion, and concrete cracking. This reduces the structural load-bearing capacity of the grain silo and compromises the airtightness of the stored grain, seriously threatening grain storage safety.

[0004] Existing protective measures for underground grain silos mostly rely on passive physical isolation methods, such as thick soil cover, high-grade concrete, waterproof membranes, salt-inhibiting admixtures, and penetrating crystalline coatings. The protective effect of these methods is highly dependent on the integrity of the materials. Once micro-cracks, joint leaks, or material aging occur, chloride ions can quickly break through the protective barrier, causing uncontrolled corrosion of the reinforcing steel.

[0005] Cathodic protection, as a mature electrochemical active protection technology, reduces the potential of reinforcing steel bars by applying an external current, thereby inhibiting the anodic dissolution reaction of the steel bars. Its effectiveness has been verified in chloride-salt corrosion environments such as seaports, offshore platforms, and subway tunnels, and it can significantly extend the service life of reinforced concrete structures. However, underground grain silos have special operating conditions such as stringent grain storage requirements, limited ventilation, high humidity, and complex sources of soil salinity. Existing cathodic protection schemes still lack systematic research on auxiliary anode materials and their arrangement, as well as their adaptability to grain storage safety.

[0006] To address this, those skilled in the art have proposed an electrochemical protection method for reinforced concrete underground grain silos. This method aims to directly cut off the corrosion potential driving force induced by chloride ions and moisture by constructing an impressed current cathodic protection system, combined with multiple types of auxiliary anodes, impermeable conductive mortar, and an intelligent monitoring and control system, thereby achieving long-term protection of the steel reinforcement in the underground grain silo structure. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides an electrochemical protection method for reinforced concrete underground grain silos, thereby resolving the issues raised in the background art regarding the reliance on physical isolation protection in existing underground grain silos, which is prone to failure and lacks durability, and the difficulty of adapting existing cathodic protection technologies to the special grain storage conditions of underground grain silos.

[0008] An electrochemical protection method for a reinforced concrete underground grain silo includes the following steps:

[0009] S1. Auxiliary anodes are continuously arranged in the cylinder wall and bottom plate structure of the underground grain silo to form a uniform electric field around the grain silo structure.

[0010] S2. Cover the steel cage with conductive mortar to form an electrical continuous system;

[0011] S3. Connect the positive terminal of the external power supply to the auxiliary anode through a rectifier, and the negative terminal to the steel mesh of the underground grain silo. Apply a constant and adjustable cathodic protection potential and current to form an impressed current cathodic protection circuit.

[0012] S4. A reference electrode is embedded in the conductive mortar to monitor the potential difference between the steel bar and the reference electrode in real time.

[0013] S5. Through the electrochemical protection monitoring and control system, the loop current of the steel bars is monitored in real time and the output current and potential are adjusted in real time according to the humidity, temperature and chloride ion concentration of the concrete pore liquid in the grain warehouse environment.

[0014] S6. Through the electrochemical protection monitoring and control system, the output current or potential is automatically adjusted according to the preset protection potential range and current density range to maintain the steel reinforcement potential at -950mV. SCE Within a range of ±50mV, constant potential or constant current control is performed.

[0015] Preferably, the conductive mortar is a cement-based impermeable conductive mortar modified by graphite powder and carbon fiber short filaments, with a volume resistivity ≤50Ω·m and a compressive strength ≥40MPa.

[0016] Preferably, the reference electrode is a silver chloride reference electrode or a copper sulfate reference electrode.

[0017] Preferably, the material of the auxiliary anode is at least one of the following, depending on the environmental conditions and construction requirements of different parts of the grain silo: conductive carbon fiber composite material, titanium-based mixed metal oxide coated mesh, conductive polymer plate, tantalum-coated titanium plate, or other corrosion-resistant conductive material.

[0018] Preferably, the auxiliary anode is arranged in at least one of the following forms: circumferential grid, partitioned sheet, vertical strip, sprayed conductive layer, or embedded strip.

[0019] Preferably, the electrochemical protection monitoring and control system has automatic data acquisition and remote monitoring functions, enabling off-site supervision and data traceability during the protection process.

[0020] Preferably, the electrochemical protection monitoring and control system includes a reference electrode array, a humidity sensor, a temperature sensor, and an automatic data acquisition and control unit, which can adjust the output current in real time according to environmental parameters.

[0021] Preferably, in the impressed current cathodic protection circuit, the current density output by the rectifier is controlled between 8 and 20 mA / m. 2 Within the specified range, this is used to match the corrosion inhibition requirements of the steel reinforcement in underground grain silos.

[0022] Preferably, the auxiliary anodes are placed in the concrete outer wall, bottom cushion layer, raft foundation or inner lining layer of the underground grain silo, or in the backfill soil around the silo wall and bottom slab.

[0023] Preferably, the rectifier has a dual-mode control function of constant potential and constant current, which can automatically switch modes according to changes in environmental parameters.

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

[0025] 1. This invention uses impressed current cathodic protection technology to maintain stable cathodic polarization of steel bars with controllable current, directly cutting off the corrosion driving force induced by chloride ions and moisture, avoiding the problems of traditional physical isolation due to cracks and aging failure, and is suitable for underground high humidity and high salt environment.

[0026] 2. This invention utilizes conductive mortar that combines low resistivity with high compressive strength and impermeability. The auxiliary anode material and arrangement are flexible, the rectifier supports dual-mode control, and the protection system does not affect grain temperature, grain quality, or airtightness, thus meeting stringent grain storage requirements.

[0027] 3. This invention, through the use of a monitoring system equipped with multiple sensors, can collect environmental parameters in real time and automatically adjust current and potential to support remote monitoring and data traceability, and can stably maintain -950mV. SCE The ±50mV protection potential significantly improves the structural durability of grain silos and reduces manual maintenance. Attached Figure Description

[0028] Figure 1 This is a flowchart of the electrochemical protection method for reinforced concrete underground grain silos according to the present invention.

[0029] Figure 2 This is a cross-sectional schematic diagram of the reinforced concrete underground grain silo of the present invention;

[0030] Figure 3 This is a schematic diagram of the electrochemical protection method for reinforced concrete underground grain silos according to the present invention. Detailed Implementation

[0031] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0032] Example 1: An electrochemical protection method for a reinforced concrete underground grain silo

[0033] This method is designed for circular reinforced concrete underground grain silos without external steel plates and is suitable for soil environments with high groundwater levels and high chloride ion concentrations (such as underground grain silos in coastal areas). The method utilizes impressed current cathodic protection technology to achieve corrosion protection of the internal steel bars of the underground grain silo's reinforced concrete structure and improve the structural durability.

[0034] The underground grain silo is a circular reinforced concrete structure, buried approximately 1.0–12m underground, with a diameter of 20–30m, wall thickness of 0.3–1.0m, top slab thickness of 0.4–1.5m, and bottom slab thickness of 0.5–2.0m. It is internally equipped with a double-layer steel mesh, with a steel reinforcement protective layer thickness of not less than 50mm, to meet the durability requirements for long-term grain storage.

[0035] The electrochemical protection system comprises three parts: auxiliary anodes, an external power supply system, and a monitoring and control system. Titanium-based mixed metal oxide (MMO) mesh auxiliary anodes are evenly installed around the perimeter of the underground grain silo in the backfill soil outside the silo. The anodes are spaced approximately 0.3–0.5 m from the underground grain silo structure and are embedded in highly conductive filler (conductive mortar or graphite sand) to ensure uniform current distribution. A mesh MMO anode strip is also arranged around the silo bottom raft, forming a closed protective ring with the anodes on the silo wall. Maintenance channels and lead-out conduits are provided between the auxiliary anodes and the conductive mortar for easy long-term maintenance.

[0036] The internal steel reinforcement of the silo is connected by reliable electrical connections to form an integrated cathode circuit, ensuring that the internal reinforcement is at the same potential during electrochemical protection. The auxiliary anode is connected to the positive terminal of the rectifier power supply via a corrosion-resistant cable, and the steel reinforcement system is connected to the negative terminal of the rectifier power supply, forming an impressed current cathodic protection current circuit. The DC rectifier has both constant potential and constant current modes, which can automatically switch according to environmental changes, and the output potential is controlled at -950mV. SCE±50mV (relative to Cu / CuSO4 electrode), current density controlled between 8 and 20 mA / m 2 Within the specified range, multiple Cu / CuSO4 reference electrodes are embedded in the concrete protective layer of the silo walls and floor slab to monitor the potential of the reinforcing bars in real time.

[0037] The data acquisition module works in conjunction with the monitoring and control system to automatically adjust the output current based on feedback from the reference electrode, maintaining the potential of the reinforcing steel system at -950mV. SCE Within a range of ±50mV (relative to the Cu / CuSO4 electrode), the system prevents overprotection from causing hydrogen evolution. The system supports remote monitoring, capable of recording real-time changes in potential, current, humidity, temperature, and groundwater level. When necessary, data can be transmitted to the management platform via a wireless network, enabling unattended operation.

[0038] After the system is operational, it continuously monitors the potential of the outer steel plate and reinforcing bars through a reference electrode, automatically adjusting the output current to achieve constant potential protection. The insulation condition of the anode cables and connection points is checked periodically, and the reference electrode is calibrated annually. The rectifier power supply is equipped with overcurrent and overvoltage protection and a power failure alarm to ensure safe operation.

[0039] This embodiment fully utilizes the conductivity and structural integrity of the internal steel reinforcement in the reinforced concrete structure of the underground grain silo to achieve cathodic protection of the steel reinforcement, effectively inhibiting electrochemical corrosion caused by chloride ions and moisture. The long-term adjustable characteristics of the impressed current protection system significantly improve the durability and grain storage safety of the underground grain silo. At the same time, the electrochemical protection system is compatible with the grain storage environment and does not affect the grain quality or airtightness, making it particularly suitable for underground grain silo projects with high groundwater levels, high salinity soils, and severe chloride ion erosion.

[0040] Example 2: An electrochemical protection method for an underground grain silo with an outer steel plate and reinforced concrete casing.

[0041] For circular reinforced concrete underground grain silos with steel plates cladding the outer wall, this method utilizes the dual function of the outer steel plate as both a construction formwork and a structural load-bearing component. It offers advantages such as readily available materials, simple construction, and the reinforcing steel plate can also serve as a formwork for concrete pouring, accelerating the construction progress. Furthermore, the problem of exposed concrete cracks can be avoided due to the steel plate cladding. Combined with an anti-rust paint coating on the steel plate surface and impressed current cathodic protection technology, synergistic corrosion protection of the outer steel plate and internal reinforcing steel are achieved, enhancing structural durability.

[0042] The underground grain silo is a circular reinforced concrete structure, buried approximately 1.0–12m underground, with a diameter of 20–30m, wall thickness of 0.3–1.0m, top slab thickness of 0.4–1.5m, and bottom slab thickness of 0.5–2.0m. The outer wall is clad with 6–12mm thick Q345 or stainless steel plates, secured by circumferential and vertical stiffeners and connected to the concrete using studs to form a composite load-bearing system. During construction, the cladding serves as permanent formwork to support the concrete pouring; after completion, it becomes part of the underground grain silo's external protection and structural system. Internally, a double-layer steel mesh is installed, with a concrete cover thickness of not less than 50mm to meet the durability requirements for long-term grain storage. The electrochemical protection system comprises three parts: auxiliary anode, external power supply system, and monitoring and control system. Titanium-based mixed metal oxide (MMO) mesh auxiliary anodes are evenly installed around the perimeter of the underground grain silo in the backfill soil outside the outer steel plate. The auxiliary anodes are spaced approximately 0.3–0.5 m from the steel plate and are embedded in highly conductive filler (conductive mortar or graphite sand) to ensure uniform current distribution. A mesh MMO anode strip is also arranged around the bottom raft plate of the silo, forming a closed protective ring with the anodes on the silo wall. Maintenance channels and lead-out conduits are provided between the auxiliary anodes and the conductive mortar for easy long-term maintenance.

[0043] The outer steel plate and the internal reinforcing steel bars are reliably electrically connected to form an integrated cathode circuit, ensuring that the steel plate and reinforcing steel bars are at the same potential during electrochemical protection. The auxiliary anode is connected to the positive terminal of the rectifier power supply via a corrosion-resistant cable, while the steel plate and reinforcing steel bars are connected to the negative terminal, forming an impressed current cathodic protection current circuit. The DC rectifier has both constant potential and constant current modes, which can automatically switch according to environmental changes, and the output potential is controlled at -950mV. SCE ±50mV (relative to Cu / CuSO4 electrode), current density controlled between 8 and 20 mA / m 2 Within the specified range, multiple Cu / CuSO4 reference electrodes are embedded in the concrete protective layer of the silo walls and floor slab for real-time monitoring of the potential of the reinforcing bars and outer steel plates. The data acquisition module is linked with the monitoring and control system, automatically adjusting the output current based on feedback from the reference electrodes to maintain the potential of the steel plate / reinforcing bar system at -950mV. SCE Within a range of ±50mV (relative to the Cu / CuSO4 electrode), the system prevents overprotection from causing hydrogen evolution. The system supports remote monitoring, capable of recording real-time changes in potential, current, humidity, temperature, and groundwater level. When necessary, data can be transmitted to the management platform via a wireless network, enabling unattended operation.

[0044] After the system is operational, it continuously monitors the potential of the outer steel plate and reinforcing bars through a reference electrode, automatically adjusting the output current to achieve constant potential protection. The insulation condition of the anode cables and connection points is checked periodically, and the reference electrode is calibrated annually. The rectifier power supply is equipped with overcurrent and overvoltage protection and a power failure alarm to ensure safe operation.

[0045] This embodiment fully utilizes the conductivity and structural integrity of the outer steel plate to achieve combined cathodic protection of the reinforcing steel and the outer steel plate, effectively suppressing electrochemical corrosion caused by chloride ions and moisture. The long-term adjustable characteristics of the impressed current protection system significantly improve the durability and grain storage safety of the underground grain silo. Simultaneously, the electrochemical protection system is compatible with the grain storage environment, does not affect grain quality or airtightness, and is particularly suitable for underground grain silo projects with high groundwater levels, high salinity soils, and severe chloride ion erosion.

[0046] Example 3: An electrochemical protection method for a prefabricated underground grain silo with an outer steel plate-concrete structure.

[0047] For circular underground grain silos with precast steel plate-concrete composite components for the silo walls, this method utilizes the high-efficiency construction advantages of prefabricated structures, which combine factory prefabrication and on-site assembly. By pre-embedding auxiliary anodes during the prefabrication stage with on-site collaborative deployment of the protection system, the construction period is shortened and the construction quality is guaranteed. Furthermore, the combined electrochemical protection of the outer steel plate and the internal steel reinforcement avoids the risk of corrosion at the assembly joints, thus achieving a dual guarantee of structural durability and grain storage safety.

[0048] The underground grain silo is a circular, prefabricated reinforced concrete structure, buried approximately 1.0–12m underground with a diameter of 20–30m. The silo walls are precast steel-concrete composite components (component height 2.0–3.0m), with the outer steel plate being 6–10mm thick Q345 or stainless steel, the inner concrete layer 0.3–0.8m thick, the top slab 0.4–1.5m thick, and the bottom slab a cast-in-place concrete raft slab (0.5–2.0m thick). The precast composite components are assembled on-site using bolts, with the joints sealed with conductive mortar. The components are internally fitted with a double-layer steel mesh, reliably connected to the outer steel plate via pre-embedded studs (250–300mm spacing) to form a composite load-bearing system. All steel reinforcement protective layers are at least 50mm thick to meet the durability requirements for long-term grain storage. The electrochemical protection system includes three parts: an auxiliary anode, an external power supply system, and a monitoring and control system. Within the concrete layer of the precast steel-concrete composite component, a titanium-based mixed metal oxide (MMO) coated mesh is uniformly embedded circumferentially as an internal auxiliary anode. After on-site assembly, tantalum-coated titanium plates embedded in strip-shaped auxiliary anodes are evenly arranged around the bottom raft slab, connected to the MMO coated mesh within the precast component via corrosion-resistant cables to form a closed protective ring. All auxiliary anodes are embedded in highly conductive filler (conductive mortar or graphite sand) to ensure uniform current distribution. Lead-out interfaces are provided for the auxiliary anodes within the precast component for on-site connection to external cables. Maintenance channels and lead-out conduits are also provided between the auxiliary anodes and the conductive mortar for long-term maintenance.

[0049] The reinforcing mesh and outer steel plate within the precast composite components are connected to the reinforcing bars of the cast-in-place base slab via on-site welding or bolting to form a reliable electrical path, constituting an integrated cathodic circuit. This ensures that the steel plate and reinforcing bars are at the same potential during electrochemical protection after assembly. The auxiliary anode (precast MMO-coated mesh + on-site tantalum-coated titanium plate) is connected to the positive terminal of the rectifier power supply via a corrosion-resistant cable, while the steel plate and reinforcing bar system are connected to the negative terminal, forming an impressed current cathodic protection current circuit. The DC rectifier has both constant potential and constant current modes, which can automatically switch according to environmental changes, with the output potential controlled at -950mV. SCE ±50mV (relative to Cu / CuSO4 electrode), current density controlled between 8 and 20 mA / m 2 Within the specified range, multiple Cu / CuSO4 reference electrodes are uniformly embedded in the concrete protective layer of the precast composite components (2-3 electrodes are pre-embedded in each component) and in the concrete protective layer of the bottom slab, with a focus on monitoring the potential of the reinforcing bars and steel plates at the assembly joints and the connection between the raft slab and the silo wall.

[0050] The data acquisition module works in conjunction with the monitoring and control system to automatically adjust the output current based on the potential data fed back from the reference electrode (paying particular attention to whether the potential at the joint deviates from the preset range), ensuring that the potential of the steel plate / reinforcing bar system is always maintained at -950mV. SCE Within a range of ±50mV (relative to the Cu / CuSO4 electrode), overprotection prevents hydrogen evolution reaction from damaging the sealing performance of the assembled joints. The system supports remote monitoring and can record changes in potential, current, ambient humidity, temperature, and groundwater level in real time. When necessary, it can transmit data to the management platform via wireless network to achieve unattended operation.

[0051] After the system is operational, the potential changes at the assembly joints and auxiliary anode connection nodes are monitored by a reference electrode, and the output current is automatically adjusted to ensure uniform protection throughout the entire structure. The insulation condition of the lead-out interfaces of the prefabricated components and the on-site cable connection nodes are checked regularly, and the reference electrode is calibrated annually. The rectifier power supply is equipped with overcurrent and overvoltage protection and a power failure alarm device to prevent damage to the prefabricated components or impact on the grain storage environment due to abnormal voltage and current.

[0052] This embodiment fully utilizes the prefabrication advantages of modular structures and the conductivity of the outer steel plate. Through a protection system combining prefabrication and on-site deployment, it achieves zero blind spots in the entire assembled structure. Impressed current cathodic protection can effectively inhibit the accumulation and corrosion of chloride ions at the assembly joints, significantly improving the durability and risk resistance of underground grain silos. At the same time, the protection system is compatible with the modular construction process, does not add extra time to the on-site construction period, and does not affect grain temperature and grain quality during operation. It is particularly suitable for the construction of large-scale underground grain silo clusters and modular grain silo projects in environments with high groundwater levels and high salinity.

[0053] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible without substantially departing from the novel teachings and advantages of the subject matter described in this application. Other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments without departing from the scope of the invention. Therefore, the invention is not limited to the particular embodiments but extends to a variety of modifications that still fall within the scope of the appended claims.

[0054] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the best mode of carrying out the invention as currently considered, or those features that are not relevant to implementing the invention) may be omitted.

[0055] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An electrochemical method of protecting a reinforced concrete underground grain bin, characterized by, The method comprises the following steps: S1, continuously arranging auxiliary anodes in the wall and floor structure of the underground warehouse for forming a uniform electric field around the warehouse structure; S2, coating conductive mortar around the steel cage to form an electrically continuous system; S3, connecting the positive pole of an external power source to the auxiliary anodes through a rectifier and connecting the negative pole to the steel mesh of the underground warehouse to apply a constant and adjustable cathodic protection potential and current to form an impressed current cathodic protection loop; S4, embedding a reference electrode in the conductive mortar for real-time monitoring of the potential difference between the steel and the reference electrode; S5, using an electrochemical protection monitoring and control system to real-time monitor the loop current of the steel and real-time adjust the output current and potential according to the humidity, temperature and chloride ion concentration of the concrete pore solution of the warehouse environment; S6. Through the electrochemical protection monitoring and control system, the output current or potential is automatically adjusted according to the preset protection potential range and current density range to maintain the steel reinforcement potential at -950mV. SCE Within a range of ±50mV, constant potential or constant current control is performed.

2. A method of electrochemical protection of a reinforced concrete underground grain storage according to claim 1, characterized in that: The conductive mortar is a graphite powder and carbon fiber short filament composite modified cement-based impermeable conductive mortar with a volume resistivity of ≤50 Ω·m and a compressive strength of ≥40 MPa.

3. The method of electrochemical protection of a reinforced concrete underground grain bin of claim 1 wherein: The reference electrode is a silver chloride reference electrode or a copper sulfate reference electrode.

4. The method of electrochemical protection of a reinforced concrete underground grain bin of claim 1 wherein: The material of the auxiliary anode is at least one of conductive carbon fiber composite material, titanium-based mixed metal oxide coating net, conductive polymer plate, tantalum-coated titanium plate or other corrosion-resistant conductive material according to the environmental conditions and construction requirements of different parts of the warehouse.

5. A method of electrochemical protection of a reinforced concrete underground grain bin as defined in claim 4, characterized in that: The arrangement form of the auxiliary anode includes at least one of the following: ring grid, partitioned sheet, vertical strip, sprayed conductive layer or embedded strip.

6. A method of electrochemical protection of a reinforced concrete underground grain bin as defined in claim 1, wherein: The electrochemical protection monitoring and control system has automatic data acquisition function and remote monitoring function, and can perform non-site supervision and data traceability during the protection process.

7. A method of electrochemical protection of a reinforced concrete underground grain bin as defined in claim 6, characterized in that: The electrochemical protection monitoring and control system comprises a reference electrode array, a humidity sensor, a temperature sensor and an automatic data acquisition control unit, and can real-time adjust the output current according to the environmental parameters.

8. The method of electrochemical protection of a reinforced concrete underground grain bin of claim 1 wherein: The impressed current cathodic protection circuit has a current density controlled at 8-20 mA / m 2 for matching the corrosion inhibition requirement of the underground warehouse steel bars.

9. A method of electrochemical protection of a reinforced concrete underground grain bin as defined in claim 5, wherein: The auxiliary anode is arranged in the concrete outer wall, warehouse bottom cushion layer, raft foundation or lining layer of the underground warehouse, or in the backfill soil around the wall and floor.

10. The method of electrochemical protection of a reinforced concrete underground grain bin of claim 1 wherein: The rectifier has constant potential and constant current dual mode control function, and can automatically switch modes according to changes in environmental parameters.

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