Cathodically protected CFRP-SMA concrete components and operation and maintenance methods

Abstract

The present invention discloses a cathodic protected CFRP-SMA concrete component and operation and maintenance method, the component includes: a plurality of longitudinal bars; a composite stirrup is wound around the plurality of longitudinal bars and insulated at the contact position; concrete, the composite stirrup and the plurality of longitudinal bars are buried in the concrete; a power source, the composite stirrup is connected to the positive pole of the power source, and the plurality of longitudinal bars are connected to the negative pole of the power source; an excitation device is connected to the composite stirrup; the composite stirrup includes a memory metal layer and a fiber reinforced composite layer, and in the initial state, the fiber reinforced composite layer is sleeved on the outer side of the memory metal layer after the pre-tension strain is generated through an insulating layer; the power source applies current to the composite stirrup as an anode to prevent the longitudinal bars from rusting, the excitation device heats up the memory metal layer, and the memory metal layer generates a restoring force to offset the tensile force lost by the degradation of the fiber reinforced composite layer, so as to provide a stable constraint to the concrete and permanently inhibit the corrosion of the longitudinal bars. The new component proposed by the present invention has good durability, controllable degradation of mechanical properties, and can be used in corrosive environments.

Description

Technical Field

[0001] The present invention relates to the technical field of reinforced concrete structures, and in particular to a cathodic protected CFRP-SMA concrete component, a preparation method and an operation and maintenance method. Background Art

[0002] Steel bars and concrete, due to their low cost, wide availability, durability and other characteristics, have become the most widely used and most in-demand building materials in the construction of civil engineering infrastructure, and the demand is increasing. However, the reinforced concrete infrastructure in coastal areas has been in high temperature, high humidity and high chloride ion environment for a long time, and the steel bars inside the concrete structure are prone to corrosion, which seriously reduces the service performance of the structure and even causes structural damage. Therefore, the durability of reinforced concrete structures serving in coastal environments has always been a difficult scientific and technological problem to overcome.

[0003] There are many ways to deal with the corrosion of steel bars in concrete. 1) Improve the impermeability of concrete or add rust inhibitors to concrete. These methods can effectively delay the corrosion of steel bars. However, it is common for concrete structures to be in service with cracks. Cracks are potential channels for corrosive media to penetrate into concrete. 2) Use corrosion-resistant reinforcement materials, such as stainless steel bars, coated steel bars, and fiber reinforced polymer (FRP) bars. However, the high cost of stainless steel bars limits their large-scale application; the anti-corrosion coating of coated steel bars has a greater risk of damage during transportation, construction, and service. Once the coating is damaged, it will cause pitting, which is more serious in the rust process; FRP has the advantages of corrosion resistance, light weight, high strength, and stable electrochemical properties. It is a potential substitute for ordinary steel bars in coastal concrete infrastructure. However, FRP's linear elasticity and tensile but not compressive stress characteristics hinder its use as longitudinal stress reinforcement, especially for bending / seismic components with high ductility requirements. It should be emphasized that CFRP as stirrups can provide a more efficient restraint effect than traditional steel stirrups, and can effectively delay the buckling of longitudinal reinforcement and the crushing of concrete, which is beneficial to improving seismic performance. 3) Cathodic protection technology can be divided into sacrificial anode cathodic protection and impressed current cathodic protection (ICCP), of which ICCP has better adaptability and durability. The stirrups in the concrete component can be replaced with CFRP stirrups, and used as the anode material for circumferential constraints. The seismic performance and bearing capacity of the component need to rely on its mechanical properties. Due to its irreplaceability and long-term requirements, the anode material is required to ensure the stability of its mechanical properties before reaching the design service life of the structure.

[0004] However, in the existing cathodic protection design, the anode material in the ICCP system has poor stability. The addition of external current will cause the anode to be worn out, which will accelerate the degradation of its mechanical properties, making the steel bars in coastal reinforced concrete structures prone to rust, resulting in poor durability of the reinforced concrete structures.

[0005] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0006] The main purpose of the present invention is to provide a cathodic-protected CFRP-SMA concrete component and an operation and maintenance method, aiming to solve the problem in the prior art that the impressed current cathodic protection of reinforced concrete structures causes anode loss, accelerates the degradation of the mechanical properties of the reinforced concrete structures, and leads to poor durability of the reinforced concrete structures.

[0007] A first aspect of an embodiment of the present application provides a cathodically protected CFRP-SMA concrete component, wherein the cathodically protected CFRP-SMA concrete component comprises:

[0008] Multiple longitudinal tendons;

[0009] Composite stirrups, wound around the plurality of longitudinal bars through insulating members;

[0010] Concrete, the composite stirrups and the plurality of longitudinal bars are embedded in the concrete;

[0011] A power source, the composite stirrups are connected to the positive electrode of the power source, and the plurality of longitudinal bars are connected to the negative electrode of the power source;

[0012] an excitation device connected to the composite stirrup;

[0013] The composite stirrup comprises a memory metal layer and a fiber-reinforced composite layer, and in an initial state, the fiber-reinforced composite layer is sleeved on the outer side of the memory metal layer after the pre-tensioning strain is generated through an insulating layer;

[0014] The power supply applies current to the composite stirrup serving as the anode. During the degradation of the fiber reinforced composite layer, the excitation device heats up the memory metal layer. The memory metal layer generates a restoring force to offset the tensile force lost due to the degradation of the fiber reinforced composite layer, so as to stably protect the plurality of longitudinal reinforcements serving as the cathode.

[0015] In a possible implementation, the excitation device is connected to both ends of the memory metal layer through excitation wires respectively; the plurality of longitudinal ribs are electrically connected, the negative electrode of the power supply is connected to the plurality of longitudinal ribs through a cathode lead-out wire, and the positive electrode of the power supply is connected to the fiber reinforced composite layer through an anode lead-out wire.

[0016] In a possible implementation, the insulating layer includes a corrugated tube and a thermal insulation paint layer, the fiber-reinforced composite layer is sleeved on the outside of the corrugated tube, and the corrugated tube is sleeved on the outside of the memory metal layer through the thermal insulation paint layer.

[0017] In a possible implementation manner, anchors are respectively provided at both ends of the composite stirrup, so that the two ends of the composite stirrup are fixed; and / or

[0018] A reinforcing rib is spirally wound around the outer side of the fiber reinforced composite layer, and the reinforcing rib is connected to the concrete.

[0019] In a possible implementation manner, the pre-tensile strain generated by the memory metal layer is in a range of 5% to 7%.

[0020] In a possible implementation, the cathodic protected CFRP-SMA concrete component further includes: a solar panel connected to the power source, the solar panel being used to store electricity and supply power to the power source; and / or

[0021] A multimeter, one end of which is connected to the cathode lead-out line, a calomel electrode is buried in the concrete, and the other end of the multimeter is connected to the calomel electrode.

[0022] In a possible implementation, the insulating component includes: a wax tube, which is sleeved on the longitudinal reinforcement; and an insulating rubber layer, one side of the insulating rubber layer is connected to the wax tube, and the other side of the insulating rubber layer is connected to the fiber reinforced composite layer.

[0023] A second aspect of an embodiment of the present application provides an operation and maintenance method for a cathodic protected CFRP-SMA concrete component, wherein the excitation temperature determination method comprises:

[0024] Obtaining an initial current density of the cathodic-protected CFRP-SMA concrete component that meets preset requirements;

[0025] Calculating the loss tension of the fiber reinforced composite layer according to the initial current density;

[0026] Calculating the current excitation temperature required for the memory metal layer according to the loss tension;

[0027] Raising the temperature of the memory metal layer according to the current excitation temperature to obtain the restoring force of the memory metal layer;

[0028] If the restoring force is greater than or equal to the loss tension, the memory metal layer is heated according to the current excitation temperature corresponding to the restoring force as the target excitation temperature.

[0029] A third aspect of an embodiment of the present application provides a method for preparing a cathodically protected CFRP-SMA concrete component, wherein the method for preparing a cathodically protected CFRP-SMA concrete component is used to prepare the cathodically protected CFRP-SMA concrete component described in any one of the above schemes, and comprises the following steps:

[0030] Obtaining the cross-sectional dimensions of the cathodic protected CFRP-SMA concrete component, the specification and quantity of the longitudinal reinforcement, and the arrangement of the composite stirrups;

[0031] According to the cross-sectional dimensions and the specification quantities, the provided plurality of longitudinal bars are formed into an initial reinforcement cage;

[0032] According to the arrangement, the prepared composite stirrups are wound around the outside of the plurality of longitudinal bars through the insulating member to obtain a target steel cage;

[0033] After the positive electrode of the provided power source is connected to the fiber reinforced composite layer of the composite stirrup and the negative electrode of the power source is connected to the longitudinal reinforcement, the provided concrete is poured into the target reinforcement cage to obtain a cathodically protected CFRP-SMA concrete component.

[0034] In a possible implementation, according to the arrangement, the prepared composite stirrups are wound around the outside of the plurality of longitudinal bars through the insulating member to obtain a target steel cage, which specifically includes:

[0035] Applying prestress to the provided shape memory metal strip for cold drawing to obtain a memory metal layer;

[0036] The insulating layer is sheathed on the outer side of the memory metal layer, and a fiber-reinforced composite layer is sheathed on the outer side of the insulating layer to obtain a composite stirrup;

[0037] According to the arrangement, the composite stirrups are wound around different positions outside the plurality of longitudinal bars through the plurality of insulating members.

[0038] Beneficial effect: The present invention provides a cathodically protected CFRP-SMA concrete component and an operation and maintenance method, in which a memory metal layer that generates pre-tensile strain in an initial state is insulated and arranged on the inner side of a fiber reinforced composite layer. In the cathodic protection technology, a power source applies current to the composite stirrups serving as an anode, so that during the degradation process of the fiber reinforced composite layer, the memory metal layer is heated by an excitation device, so that the memory metal layer generates a restoring force to offset the tensile force lost by the degradation of the fiber reinforced composite layer, thereby protecting a plurality of longitudinal bars serving as cathodes while ensuring the mechanical properties of the entire concrete component, thereby improving the stability and durability of the concrete component. The new structure has good durability, controllable degradation of mechanical properties, and can serve in a corrosive environment.

[0039] In addition to the technical problems solved by the present application, the technical features that constitute the technical solutions, and the beneficial effects brought about by the technical features of these technical solutions described above, other technical problems that can be solved by the cathodic protected CFRP-SMA concrete components and operation and maintenance methods provided by the present application, other technical features included in the technical solutions, and the beneficial effects brought about by these technical features will be further described in detail in the specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 A schematic structural diagram of a cathodic-protected CFRP-SMA concrete component provided in an embodiment of the present application;

[0042] Figure 2 A schematic diagram of the shape memory effect of the SMA layer of the cathodic protected CFRP-SMA concrete component provided in an embodiment of the present application;

[0043] Figure 3 A schematic diagram of a CFRP-SMA composite reinforcement material of a cathodic-protected CFRP-SMA concrete component provided in an embodiment of the present application;

[0044] Figure 4 A schematic diagram of a corrosion monitoring system for a cathodic-protected CFRP-SMA concrete component provided in an embodiment of the present application;

[0045] Figure 5 A schematic diagram of CFRP-SMA spiral stirrups wrapped around longitudinal reinforcement of a cathodic-protected CFRP-SMA concrete member provided in an embodiment of the present application;

[0046] Figure 6 A schematic diagram of the composite stirrup and anchor connection of the cathodic protected CFRP-SMA concrete member provided in an embodiment of the present application;

[0047] Figure 7 A schematic diagram of another angle of connection between the composite stirrups and the anchorage of the cathodic-protected CFRP-SMA concrete member provided in an embodiment of the present application;

[0048] Figure 8 is a flow chart of the operation and maintenance method provided in an embodiment of the present application;

[0049] Fig. 9It is a flowchart of specific implementation steps of the operation and maintenance method provided in the embodiment of the present application;

[0050] Fig.10 A graph showing the loss of CFRP tensile strength for the operation and maintenance method provided in an embodiment of the present application;

[0051] Fig.11 The ratio of the seismic performance of the ICCP concrete column of the operation and maintenance method provided in the embodiment of the present application to the seismic performance of the control group (without ICCP system);

[0052] Fig.12 It is a flow chart of a method for preparing a cathodically protected CFRP-SMA concrete component provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical scheme and effect of the present invention clearer and more specific, the technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0054] The following describes the cathodic protection CFRP-SMA concrete component and operation and maintenance method of the embodiment of the present application with reference to the accompanying drawings. In view of the problem that the cathodic protection of the reinforced concrete structure caused the loss of the anode in the above-mentioned related technology, the mechanical properties of the reinforced concrete structure are accelerated to degrade, resulting in poor durability of the reinforced concrete structure, the present application provides a cathodic protection CFRP-SMA concrete component, in which the memory metal layer that produces pre-tension strain in the initial state is insulated and arranged on the inner side of the fiber reinforced composite layer, and the power supply in the cathodic protection technology applies current to the composite stirrups as the anode, so that during the deterioration of the fiber reinforced composite layer, the memory metal layer is heated by the excitation device to make the memory metal layer generate a restoring force to offset the tensile force lost by the deterioration of the fiber reinforced composite layer, thereby protecting the multiple longitudinal bars as the cathode under the premise of ensuring the mechanical properties of the entire concrete component, thereby improving the stability and durability of the concrete component. Thus, the technical problem that the cathodic protection of the reinforced concrete structure caused the loss of the anode in the related technology, the mechanical properties of the reinforced concrete structure are accelerated to degrade, resulting in poor durability of the reinforced concrete structure is solved.

[0055] This application innovatively introduces shape memory alloy (SMA) and CFRP to form an intelligent driven composite reinforcement, which serves as both the stirrup of the concrete component and the anode of the ICCP system. The cathodic protection circuit system can serve as the thermal excitation of the SMA, triggering its phase change in a timely, multiple and gradual manner to generate pre-tension stress, compensating for the stress loss of CFRP during the long-term operation of ICCP.

[0056] The following specific embodiments are used to describe in detail the technical solution of the present application and how the technical solution of the present application solves the above technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0057] like Figure 1 As shown, an embodiment of the present application provides a cathodic protected CFRP-SMA concrete component, characterized in that the cathodic protected CFRP-SMA concrete component comprises:

[0058] Multiple longitudinal tendons;

[0059] Composite stirrups, wound around the plurality of longitudinal bars through insulating members;

[0060] Concrete, the composite stirrups and the plurality of longitudinal bars are embedded in the concrete;

[0061] A power source, the composite stirrups are connected to the positive electrode of the power source, and the plurality of longitudinal bars are connected to the negative electrode of the power source;

[0062] an excitation device connected to the composite stirrup;

[0063] The composite stirrup comprises a memory metal layer (SMA layer) and a fiber reinforced composite layer (CFRP layer). In the initial state, the fiber reinforced composite layer is sleeved on the outer side of the memory metal layer after the pre-tensioned strain is generated (that is, the SMA layer is stretched and has residual strain) through an insulating layer;

[0064] The power supply applies current to the composite stirrups serving as the anode. During the degradation process of the fiber reinforced composite layer, the excitation device heats up the memory metal layer. The memory metal layer generates a restoring force to offset the tensile force lost due to the degradation of the fiber reinforced composite layer, so as to stably protect the plurality of longitudinal reinforcements serving as the cathode, thereby providing stable constraints on the concrete and permanently inhibiting the corrosion of the longitudinal reinforcements, so that the component has the characteristics of good durability, controllable degradation of mechanical properties, and can serve in a corrosive environment.

[0065] It should be noted that the composite stirrups are CFRP-SMA composite reinforcements, the fiber-reinforced composite layer is a carbon fiber reinforced composite material (CFRP), and the memory metal layer is a shape memory metal material; the fiber-reinforced composite layer and the insulating layer are both tubular, the memory metal layer is a solid strip, and the outer side of the solid strip memory metal layer is coated by the fiber-reinforced composite layer through the outer insulating layer, that is, the CFRP layer and the SMA layer are not conductive, but because the CFRP layer and the SMA layer are bonded and connected at various locations through the insulating layer, when the CFRP layer is electrically degraded, the SMA layer is heated to restore its original length, thereby giving a restoring force to the CFRP layer through the insulating layer, so that the composite stirrups can have better mechanical properties when connected to concrete, thereby making the concrete member have better mechanical properties and ductility, so as to improve the durability and stability of the concrete member.

[0066] The embodiment of the present application introduces shape memory metal SMA into the cathodic protection system; SMA is a type of alloy material that can "remember" its initial shape. Since it has both sensing and driving functions, it is a smart material; the two special macroscopic mechanical properties of SMA, shape memory effect (SME) and superelasticity (SE), are caused by its internal microscopic phase change mechanism. Figure 2 The shape memory effect refers to the residual strain after unloading when the ambient temperature of SMA is lower than its phase transition temperature. If the SMA is heated at this time, the residual strain will disappear and the SMA will completely recover to its shape before loading. Superelasticity refers to the phenomenon that when the SMA is at a higher ambient temperature, stress is applied to it to cause a large deformation. After the stress is released, the SMA can still recover to its original shape before deformation. At the same time, shape memory alloys have a large resistivity and can even be used as heating wires. Therefore, the SMA wire can be directly heated to increase its temperature and deform it. Therefore, this characteristic of SMA can be used to compensate for the degradation of the mechanical properties of the anode material caused by material loss.

[0067] like Figure 1 As shown in the figure, the method of composite stirrups (i.e., CFRP-SMA composite reinforcement) is as follows: first, the SMA is cold-drawn to apply prestress to achieve a strain of 6%, and then a layer of plastic bellows is applied, and the plastic bellows is filled with insulating paint. Finally, a layer of CFRP is applied to the plastic bellows. It is worth noting that the paint has fast curing and low shrinkage properties, and is also a good thermal insulation material. Excessive temperature will cause the outer layer of CFRP to carbonize and decompose, resulting in a decrease in or even loss of its mechanical properties.

[0068] That is to say, prestress is applied to the memory metal layer (SMA layer) by cold drawing. For example, a 10m long memory metal strip is stretched to 10.6m, which means a strain of 6%. Then the prestress on the memory metal strip is removed, so that the 10.6m memory metal strip gradually recovers but there is still residual strain (that is, the current length is between 10-10.6). After standing, the memory metal strip (SAM layer) and the fiber reinforced composite layer (CFRP layer) are installed through the insulating layer (that is, the paint inside the corrugated tube).

[0069] The working principle of the CFRP-SMA stirrup reinforced concrete member based on impressed current cathodic protection technology (ICCP) in the embodiment of the present application to improve the durability of the concrete member is: first, the corrosion-resistant CFRP-SMA stirrups are used to replace the traditional steel stirrups closest to the concrete surface, which naturally delays the rusting time of the steel bars (longitudinal bars); at the same time, compared with the steel stirrups that are easy to yield, the tensile strength of the fiber reinforced composite layer is higher, that is, the CFRP layer in the CFRP-SMA stirrups (composite stirrups) can provide better constraints for the concrete structure because its tensile force increases linearly with deformation; second, the steel longitudinal bars are retained, so as to ensure the ductility requirements of the structure, especially in areas facing earthquake risks, the ductility must meet the requirements; third, the CFRP layer (fiber reinforced composite layer) is used as the anode of the ICCP, and a certain amount of current is provided to the longitudinal bars through an external DC power supply, so that the surface of the longitudinal bars (cathode) is cathodically polarized, thereby causing the anode reaction of the corrosion of the longitudinal bars (Fe is oxidized to Fe 2+ ) is suppressed, thereby preventing the corrosion of the longitudinal reinforcement; Fourth, the inner layer of SMA (i.e., the memory metal layer) is cold-drawn to apply prestress. After the CFRP deteriorates, the SMA is electrically heated to restore it to its original shape to generate contraction stress to compensate for the CFRP tension. It is worth noting that the SMA can only be stimulated (heated) when the CFRP deteriorates to a certain extent, otherwise the excessive tension generated will cause tensile damage to the concrete in the CFRP-SMA anchorage area, and at the same time destroy the bonding performance between the stirrups and the concrete; Fifth, Fe-SMA has a secondary excitation characteristic, that is, the first excitation to a lower temperature and then the second excitation to a higher temperature. Compared with the restoring force of the first excitation, the secondary excitation can produce a higher level of restoring force. The gradual heating method can be used to determine the optimal temperature for exciting the SMA. The present invention not only utilizes the advantages of high strength, high confinement efficiency and corrosion resistance of CFRP bars, but also uses its conductivity to serve as the anode of ICCP to inhibit the corrosion of the longitudinal bars, thereby significantly enhancing the durability of the structure while ensuring the mechanical properties and ductility of the structure. It also utilizes the shape memory effect of SMA to ensure the stability of the long-term performance of the concrete structure, providing a scientific basis and effective technical approach for the construction, operation and maintenance of coastal concrete infrastructure.

[0070] Therefore, for concrete components serving in coastal corrosive environments, the durability of concrete components can be improved by using composite stirrups (i.e., CFRP-SMA spiral bars) as stirrups for concrete components (such as concrete composite columns and concrete composite beams) while still using traditional steel bars for the longitudinal reinforcement. Figure 3 The concrete component of the present invention has the following key points: the power supply of ICCP has a long-term stable power supply capacity; it has a corrosion detection function, and the cathodic protection function is activated when the steel bar corrodes to a certain extent; SMA can be externally connected to an excitation (heating) device; it can calculate the minimum current density that can effectively prevent steel bar corrosion and does not affect the long-term performance of CFRP-SMA stirrups; it can calculate the time for SMA to start excitation; it can calculate the optimal temperature for SMA excitation.

[0071] In the embodiment of the present application, CFRP-SMA spiral reinforcement (i.e., composite stirrups) is used, and the CFRP layer (fiber reinforced composite layer) and the SMA layer (memory metal layer) in the CFRP-SMA are insulated from each other, and play their respective functions, that is, the CFRP layer serves as a stirrup for structural stress, and also as an anode to protect the longitudinal reinforcement of the cathodic protection system from corrosion; the SMA layer in the component also plays a dual function, serving as a stirrup for structural stress, and using its restoring force to compensate for the tensile loss of CFRP; at the same time, CFRP and SMA can act as a whole to provide circumferential constraint for the concrete structure.

[0072] In one embodiment of the present invention, Figure 1 , Figure 6 and Figure 7 As shown, the excitation device is connected to both ends of the memory metal layer through excitation wires respectively; the plurality of longitudinal ribs are electrically connected, the negative pole of the power supply is connected to the plurality of longitudinal ribs through a cathode lead-out wire, and the positive pole of the power supply is connected to the fiber reinforced composite layer through an anode lead-out wire.

[0073] Specifically, the memory metal layer in the fiber reinforced composite layer is heated by an excitation wire connected to an excitation device, that is, the SMA layer is used as a heating wire (the SMA layer has a large resistivity), so that the SMA layer deforms and gradually recovers its length after the temperature rises (the length of the memory metal strip with residual strain gradually decreases, and is reduced to the original length at most). It can be understood that the excitation device can be a high-power power supply, but is not limited to this. The excitation device is a device that can provide current to the SMA layer, such as a transformer or a rectifier, which is not specifically limited here.

[0074] like Figure 1As shown, the cathode lead wire connects the multiple longitudinal bars respectively, and the cathode lead wire lead-out wire is connected to the negative pole of the power supply, and the two ends of the anode lead wire are directly connected to the positive pole of the power supply and the CFRP layer respectively, so that the positive pole of the power supply-CFRP layer-multiple longitudinal bars-negative pole of the power supply form a current loop for cathodic protection.

[0075] In one embodiment of the present invention, Figure 3 and Figure 6 As shown, the insulating layer includes a corrugated tube and a heat-insulating paint layer, the fiber-reinforced composite layer is sleeved on the outside of the corrugated tube, and the corrugated tube is sleeved on the outside of the memory metal layer through the heat-insulating paint layer.

[0076] Specifically, the corrugated pipe is a plastic corrugated pipe, and insulating paint (i.e., thermal insulation paint layer) is filled in the plastic corrugated pipe. The thermal insulation paint layer has fast curing and low shrinkage properties and is also a good thermal insulation material. A CFRP layer is provided on the outside of the plastic corrugated pipe, and an SMA layer is wrapped on the inside of the plastic corrugated pipe by a thermal insulation paint layer.

[0077] In one embodiment of the present invention, Figure 6 and Figure 7 As shown, anchors are respectively provided at both ends of the composite stirrups to fix the two ends of the composite stirrups.

[0078] Specifically, the anchor includes a base and a bolt, the base has a through hole and a threaded hole that are connected, the CFRP layer is arranged in contact with the inner wall of the through hole, and the bolt is in contact with the CFRP layer through the threaded hole, so that the CFRP layer, the insulating layer and the SMA layer of the composite stirrup are more stable, and the two ends of the composite stirrup are fixed, so that when the excitation device heats up the SMA layer, the SMA layer heats up to generate a restoring force, and then the parts of the two ends of the composite stirrup offset the tensile force lost by the deterioration of the CFRP layer under the action of the restoring force of the SMA layer, so as to achieve the effect of compensating for the loss of the CFRP layer as the anode material and causing the decline in mechanical properties, so as to improve the stability and durability of the concrete member.

[0079] In one embodiment of the present invention, Figure 3 As shown, the outer side of the fiber reinforced composite layer (the side close to the concrete is provided with ribs, while the side close to the longitudinal reinforcement is not provided with ribs) is spirally coiled with reinforcing ribs, and the reinforcing ribs are connected to the concrete. Specifically, the middle part of the CFRP layer has a spiral reinforcing rib, which is stably connected to the concrete through the reinforcing ribs to ensure the mechanical properties of the concrete component.

[0080] In an embodiment of the present invention, the pre-tensile strain generated by the memory metal layer is within a range of 5% to 7%.

[0081] Specifically, in this embodiment, the pre-tensioned strain generated by the memory metal layer is 6%, and the pre-tensioned strain is the strain achieved after prestress is applied to the SMA tendons. For example, a 10m memory metal strip has a length of 10.6m when a 6% pre-tensioned strain is generated. The memory metal layer after the pre-tensioned strain is generated is a state in which the SMA tendons have residual strain after the prestress is unloaded, that is, the length of the memory metal layer after the pre-tensioned strain is greater than 10m and less than 10.6m.

[0082] In one embodiment of the present invention, Figure 1 As shown, the cathodic-protected CFRP-SMA concrete component further includes: a solar panel connected to the power source, the solar panel being used to store electricity and supply power to the power source. Specifically, the power source (i.e., the power storage device) and the solar panel (i.e., the solar power generation device) form a solar energy system, and the solar energy is used as the power source for the cathodic protection through the solar energy system.

[0083] In one embodiment of the present invention, Figure 1 and Figure 4 As shown, the cathodically protected CFRP-SMA concrete component also includes: a multimeter, one end of the multimeter is connected to the cathode lead, a calomel electrode is buried in the concrete, and the other end of the multimeter is connected to the calomel electrode. Specifically, the calomel electrode is buried in the concrete of the corresponding area, and the concrete is conductive, so that the voltage and / or current can be measured between the cathode lead and the calomel electrode in the corresponding area by the multimeter. That is, the embodiment of the present application adds a corrosion monitoring system to the component, so that the cathodic protection function can be immediately activated when the longitudinal reinforcement in the component is corroded to a certain extent.

[0084] In one embodiment of the present invention, Figure 5 As shown, the insulating component includes: a yellow wax tube, which is sleeved on the longitudinal reinforcement; an insulating rubber layer, one side of the insulating rubber layer is connected to the yellow wax tube, and the other side of the insulating rubber layer is connected to the fiber reinforced composite layer.

[0085] Specifically, the CFRP-SMA spiral reinforcement (composite stirrups) are wrapped around the longitudinal reinforcement, a layer of yellow wax tube is put on the junction of the longitudinal reinforcement and the CFRP layer, and insulating glue is applied between the longitudinal reinforcement and the yellow wax tube for bonding (i.e., an insulating glue layer is formed, and no bonding is required between the spiral reinforcement and the longitudinal reinforcement) to ensure the insulation of the longitudinal reinforcement and the composite stirrups.

[0086] In one embodiment of the present invention, the plurality of longitudinal bars and the concrete form a circular cross-section, the plurality of longitudinal bars are distributed in a circular array within the edge of the concrete, and the composite stirrups are spirally wound around the outer sides of the longitudinal bars.

[0087] In another embodiment of the present invention, the plurality of longitudinal bars and the concrete may also form a square cross section, and the composite stirrups are spirally arranged outside the longitudinal bars. That is, the present invention does not limit the contour shape of the concrete composite component, which may be Figure 1 It can be a concrete column, a concrete beam, or other shapes.

[0088] Next, the operation and maintenance method of the CFRP-SMA concrete component based on the cathodic protection in the above embodiment proposed in the embodiment of the present application is described with reference to the accompanying drawings.

[0089] Figure 8 It is a flow chart of the operation and maintenance method of an embodiment of the present application.

[0090] like Figure 8 As shown, the operation and maintenance method includes the following steps:

[0091] In step S101, the initial current density of the cathodic protected CFRP-SMA concrete component that meets the preset requirements is obtained;

[0092] In step S102, the loss tension of the fiber reinforced composite layer is calculated according to the initial current density;

[0093] In step S103, the current excitation temperature required for the memory metal layer is calculated according to the loss tension;

[0094] In step S104, the memory metal layer is heated according to the current excitation temperature to obtain the restoring force of the memory metal layer;

[0095] In step S105, if the restoring force is greater than or equal to the loss tension, the memory metal layer is heated according to the current excitation temperature corresponding to the restoring force as the target excitation temperature.

[0096] In the embodiment of the present application, the optimal excitation temperature is determined by the size of the protection current density, the power-on time and the designed service life, so that the SMA layer is heated according to the excitation temperature, and the SMA layer gradually recovers (reduces) its length, thereby compensating for the degradation of mechanical properties caused by the loss of CFRP layer materials, so as to achieve the effect of improving the durability of concrete components.

[0097] The following further introduces the entire implementation process according to the steps of the operation and maintenance method of the zoned cathodic protection of this application. Fig. 9 As shown:

[0098] S1, based on the cross-sectional dimensions of the concrete column, the tensile strength of the longitudinal reinforcement, the tensile strength of the CFRP-SMA spiral stirrups, the arrangement of the CFRP-SMA stirrups, the arrangement of the longitudinal reinforcement, and the reinforcement ratio.

[0099] S2, calculate the bearing capacity (F) and ductility (μ) of the component.

[0100] S3, determine whether the bearing capacity (F) and ductility (μ) of the component are greater than the design value of the bearing capacity (F d ) and ductility design value (μ d ). If yes, proceed to S4, if no, return to S2. Adjust the cross-sectional dimensions of the concrete column, the tensile strength of the longitudinal reinforcement and other parameters.

[0101] S4, the component is put into use and the timing starts.

[0102] S5, based on the principle of corrosion electrochemistry, uses the half-potential measurement method to evaluate the corrosion status of the steel bars and detect the effect of cathodic protection to achieve the monitorability of the structural data. Connect one end of the potentiometer to the longitudinal reinforcement lead and the other end to the reference electrode close to the structure. According to the American Society for Testing and Materials standard ASTM C876-09 (see Table 1), the method of determining the corrosion status of the steel bars by measuring the corrosion potential of the steel bars in the concrete records the time t taken for the potential of each partition to reach -276Mv 1 ,t 2 ,…,t n , and start the cathodic protection system.

[0103] Table 1. Relationship between steel bar corrosion potential and corrosion probability

[0104]

[0105] S6, gives the initial current density that meets the service life requirements of the structure. Due to the large differences in the degree of corrosion of steel bars under different corrosion environments, see Figure 7 The current density of each area can be appropriately adjusted according to the above steel corrosion assessment method. The calculation method of protection current density is shown in formula (1).

[0106]

[0107] Among them, i' is the protection current density, Q is the total electric flux of the CFRP anode calculated based on the service life of the structure, k is the adjustment factor, and t is the time taken for the concrete component to start cathodic protection from the beginning of service.

[0108] S7, calculate the tensile strength of the longitudinal reinforcement when the component reaches the design service life under cathodic protection conditions (f y ) and the tensile strength of the composite stirrups (f f ), see formula (2), formula (3):

[0109] f y =f(ρ,t,i 0 ); (2)

[0110] f f =f(t,i 0 ); (3)

[0111] Among them, ρ is the corrosion rate of longitudinal reinforcement, i 0 is the initial value of the current density when cathodic protection is just turned on;

[0112] Calculate the bearing capacity of the component when it reaches the design service life (F t ) and ductility (μ t ), see formula (4), formula (5):

[0113] F t =F(f y ,f t ); (4)

[0114] μ t =G(f y ,f t ); (5)

[0115] S8, determine the bearing capacity of the component when it reaches the design service life (F t ) and ductility (μ t ) is greater than the design value of the bearing capacity (F d ) and the design value of ductility (μ d ). If yes, proceed to S9, if no, adjust the current density, and then return to S6.

[0116] S9, recording various parameters that meet the conditions, and inputting i' that meets the conditions into the solar energy system, the solar energy system outputs the protection current according to the current density, and starts the cathodic protection system.

[0117] S10, use a potentiometer (multimeter) to monitor the current density i in real time, and monitor the longitudinal reinforcement corrosion rate (ρ) every month.

[0118] S11, calculate the corrosion growth rate λ, see formula (6).

[0119]

[0120] Where ρ' is the corrosion rate of the longitudinal reinforcement in the current month (previous month), ρ″ is the corrosion rate of the longitudinal reinforcement in the next month (current month), t m Is a fixed value.

[0121] S12, determine whether the corrosion growth rate of the longitudinal reinforcement is within the ideal range, i.e., λ 0 ≥λ≥λ t . 0 is the corrosion growth rate of the longitudinal reinforcement without cathodic protection, t The maximum current density i that does not affect the seismic performance of the structure under the cathodic protection system0 (See Fig.11 ) under the condition of longitudinal reinforcement corrosion growth rate. The reason is as follows: for the structure where steel bar corrosion has occurred and cathodic protection is turned on, the selection of protection current density is extremely critical: if the protection current density is too small, the cathodic protection effect cannot be achieved; if it is too large, over-protection will occur, which will cause acidification of the interface between steel bar and concrete, affect the bonding between steel bar and concrete, and cause accelerated deterioration of CFRP strip stirrups (see Fig.10 ), resulting in a decrease in the seismic performance of the structure (see Fig.11 , in 0-i 0 F / F 0 That is, the performance meets the requirements).

[0122] S13, output the current density i of the cathodic protection system.

[0123] S14, calculate the tensile strength f' of the degraded CFRP layer, once a month, see formula (7).

[0124] f'=g(i,t,f f ); (7)

[0125] S15, judging whether the tensile strength f' of the CFRP layer is greater than the tensile strength f of the CFRP layer when the design service life is reached 0 , when f 0 When ≤f', record the time t' and calculate the excitation temperature T of SMA, see formula (8).

[0126] T=h(f'); (8)

[0127] Calculate the tensile force F lost after deterioration of the CFRP layer l , calculated once a month, see formula (9).

[0128] F l =(f f -f')×s 1 ; (9)

[0129] Where f' is the tensile strength of the CFRP layer after degradation, s 1 is the cross-sectional area of ​​the CFRP layer.

[0130] S16, operating the excitation device, raising the temperature to T to excite the SMA.

[0131] S17, calculate the recovery stress ω and recovery force F of SMA h , see formula (10), (11).

[0132] ω=l(T); (10)

[0133] F h=ω×s 2 ; (11)

[0134] where s 2 is the cross-sectional area of ​​the SMA layer.

[0135] S18, determine the restoring force F of SMA h Is it greater than the tensile force F lost by the CFRP layer? l If yes, then the optimal excitation temperature T is output. If no, then the excitation temperature is appropriately increased and the process returns to S15.

[0136] Therefore, under the successful operation of the cathodic protection system, the embodiment of the present application can keep the corrosion rate of the steel bars within a certain range, and neither the corrosion rate can be too fast, nor can it be too slow or even the corrosion degree cannot develop. The corrosion rate represents that the current density of the cathodic protection system is too large, but the structural bearing capacity is reduced. The optimal current density of the cathodic protection is obtained by the corrosion development rate λ, and then the tensile force lost by the CFRP layer is obtained according to λ, so as to deduce the optimal excitation temperature of the SMA layer. Under this temperature excitation, the restoring force of the SMA layer can just make up for the tensile force lost by the degradation of the CFRP layer, so that the system can maintain the stability of the bearing capacity and good seismic performance under long-term conditions in the coastal environment.

[0137] Fig.12 It is a flow chart of a method for preparing a cathodic-protected CFRP-SMA concrete component according to an embodiment of the present application.

[0138] like Fig.12 As shown, the method for preparing a cathodic protected CFRP-SMA concrete component comprises the following steps:

[0139] In step S201, the cross-sectional dimensions of the cathodic protected CFRP-SMA concrete component, the specification and quantity of the longitudinal reinforcement, and the arrangement of the composite stirrups are obtained;

[0140] In step S202, the provided plurality of longitudinal bars are formed into an initial reinforcement cage according to the cross-sectional size and the specification usage;

[0141] In step S203, according to the arrangement mode, the prepared composite stirrups are wound around the outside of the plurality of longitudinal bars through the insulating member to obtain a target steel cage;

[0142] In step S204, the positive electrode of the provided power source is connected to the fiber reinforced composite layer of the composite stirrup, and the negative electrode of the power source is connected to the longitudinal reinforcement, and then the provided concrete is poured into the target reinforcement cage to obtain a cathodically protected CFRP-SMA concrete component.

[0143] In a possible implementation, in step S203, the provided shape memory metal strip is subjected to prestressing and cold drawing to obtain a memory metal layer; the insulating layer is sleeved on the outside of the memory metal layer, and a fiber-reinforced composite layer is sleeved on the outside of the insulating layer to obtain composite stirrups; according to the arrangement, the composite stirrups are wrapped around different positions on the outside of the plurality of longitudinal bars through a plurality of the insulating members.

[0144] After completing the design of the cathodic protection CFRP-SMA spiral stirrup concrete composite column, the component size, CFRP-SMA spiral reinforcement configuration, the specification and amount of longitudinal reinforcement, and the cathodic protection operation parameter settings are determined, and the CFRP-SMA spiral stirrup concrete column can be prepared. This structural system is intended to overcome the problem of easy corrosion of steel bars in traditional reinforced concrete structural systems in coastal environments, while using the excellent mechanical and electrochemical properties of CFRP-SMA materials to achieve the goals of improving structural strength, inhibiting steel corrosion, and achieving cathodic protection and SMA prestress compensation. The structural system includes CFRP-SMA spiral bars, concrete, longitudinal steel bars, frame steel bars, insulating materials, potentiometers, high-power excitation equipment, and solar panels.

[0145] The entire implementation process is further described below according to the steps of the method for preparing the CFRP-SMA concrete component with cathodic protection of the present application:

[0146] K1, combine multiple longitudinal bars into the initial reinforcement cage. Multiple longitudinal bars can be divided into tensile longitudinal bars, compressive steel bars, and frame bars.

[0147] Note: The erection steel bars should be arranged at both ends and in the middle of the beam to ensure the initial stiffness of the steel cage.

[0148] K2, first make CFRP-SMA straight bars, cold-draw SMA to apply prestress to reach 6% strain, then coat it with a layer of plastic corrugated tube, fill the plastic corrugated tube with gelling paint, and finally coat the plastic corrugated tube with a layer of CFRP. After the CFRP-SMA straight bars are made, they are made into spiral stirrups according to the stirrup ratio and specification requirements.

[0149] K3, the contact position between CFRP-SMA spiral stirrups and longitudinal tensile reinforcement and compressive reinforcement is cleaned, then coated with insulating glue and left to solidify.

[0150] K4, wrap the CFRP-SMA spiral reinforcement around the initial reinforcement cage according to the design method, put a layer of yellow wax tube on the joint between the longitudinal reinforcement and CFRP-SMA, and bond them with insulating glue to ensure the insulation between the longitudinal reinforcement and the CFRP spiral stirrup (see Figure 5 ).

[0151] K5, let the steel cage stand still and wait for the conductive glue on the CFRP-SMA spiral reinforcement to dry and solidify.

[0152] K6, lead out the wires on the protected longitudinal reinforcement (cathode) and CFRP-SMA spiral stirrups (anode) (see Figure 2 and Figure 6 ), connect the outer layer of CFRP, and seal the wire connection with insulating tape; lead out the wire on the CFRP-SMA spiral stirrup ( Figure 2 ,6), connect the inner layer SMA and seal the wire connection with insulating tape.

[0153] K7, put anchors on both ends of CFRP-SMA (see Figure 6 and Figure 7 ).

[0154] K8, concrete pouring and component maintenance.

[0155] K9, connects the solar panel with power storage function and the potentiometer.

[0156] K10, connect high-power excitation equipment.

[0157] The method for preparing the cathodically protected CFRP-SMA concrete component provided by the present invention is used to prepare the above-mentioned cathodically protected CFRP-SMA concrete component, thereby having all the beneficial effects of the above-mentioned cathodically protected CFRP-SMA concrete component, which will not be repeated here.

[0158] In the description of this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0159] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0160] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0161] It should be noted that: in this application, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0162] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0163] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0164] In general, terms should be understood, at least in part, by the context in which they are used. For example, the term "one or more" as used herein may be used to describe any feature, structure, or characteristic in a singular sense, or may be used to describe a combination of features, structures, or characteristics in a plural sense, depending, at least in part, on the context. Similarly, terms such as "a," "an," or "the" may also be understood to convey singular usage or to convey plural usage, depending, at least in part, on the context.

[0165] It should be easily understood that “on,” “above,” and “over” in the present disclosure should be interpreted in the broadest manner, so that “on” not only means “directly on something,” but also includes the meaning of “on something” with intervening features or layers therebetween, and “above” or “over” not only includes the meaning of “above” or “over,” but also may include the meaning of “above” or “over something” with no intervening features or layers therebetween (i.e., directly on something).

[0166] Spatially relative terms, such as "below," "below," "beneath," "above," "above," etc., may be used herein for ease of description to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. The device may have other orientations (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein should be interpreted accordingly.

[0167] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for operating and maintaining a cathodically protected CFRP-SMA concrete component, characterized in that: The cathodic protected CFRP-SMA concrete component comprises: Multiple longitudinal tendons; Composite stirrups, wound around the plurality of longitudinal bars through insulating members; Concrete, the composite stirrups and the plurality of longitudinal bars are embedded in the concrete; A power source, the composite stirrups are connected to the positive electrode of the power source, and the plurality of longitudinal bars are connected to the negative electrode of the power source; an excitation device connected to the composite stirrup; The composite stirrup comprises a memory metal layer and a fiber-reinforced composite layer, and in an initial state, the fiber-reinforced composite layer is sleeved on the outer side of the memory metal layer after the pre-tensioning strain is generated through an insulating layer; The power supply applies current to the composite stirrup as an anode, and during the degradation process of the fiber reinforced composite layer, the excitation device heats up the memory metal layer, and the memory metal layer generates a restoring force to offset the tensile force lost by the degradation of the fiber reinforced composite layer, so as to stably protect the plurality of longitudinal bars as cathodes; The excitation device is connected to two ends of the memory metal layer via excitation wires respectively; The plurality of longitudinal ribs are electrically connected, the negative electrode of the power source is connected to the plurality of longitudinal ribs through a cathode lead-out line, and the positive electrode of the power source is connected to the fiber-reinforced composite layer through an anode lead-out line; the insulating layer comprises a bellows and a heat-insulating paint layer, the fiber-reinforced composite layer is sleeved on the outside of the bellows, and the bellows is sleeved on the outside of the memory metal layer through the heat-insulating paint layer; The pre-tension strain generated by the memory metal layer is within a range of 5% to 7%; The fiber reinforced composite layer and the insulating layer are both in a tubular shape, the memory metal layer is in a solid strip shape, the fiber reinforced composite layer and the memory metal layer are not electrically conductive, and when the memory metal layer is heated, the memory metal layer provides a restoring force to the fiber reinforced composite layer through the insulating layer; The operation and maintenance method comprises: Obtaining an initial current density of the cathodic-protected CFRP-SMA concrete component that meets preset requirements; Calculating the loss tension of the fiber reinforced composite layer according to the initial current density; Calculating the current excitation temperature required for the memory metal layer according to the loss tension; Raising the temperature of the memory metal layer according to the current excitation temperature to obtain a restoring force of the memory metal layer; If the restoring force is greater than or equal to the loss tension, the memory metal layer is heated according to the current excitation temperature corresponding to the restoring force as the target excitation temperature.

2. The operation and maintenance method of the cathodic protected CFRP-SMA concrete component according to claim 1, characterized in that: Anchors are respectively provided at both ends of the composite stirrups to fix the two ends of the composite stirrups; and / or A reinforcing rib is spirally wound around the outer side of the fiber reinforced composite layer, and the reinforcing rib is connected to the concrete.

3. The operation and maintenance method of the cathodic protected CFRP-SMA concrete component according to claim 1, characterized in that: The cathodic protected CFRP-SMA concrete component further comprises: a solar panel connected to the power source, the solar panel being used to store electricity and supply power to the power source; and / or A multimeter, one end of which is connected to the cathode lead-out line, a calomel electrode is buried in the concrete, and the other end of the multimeter is connected to the calomel electrode.

4. The operation and maintenance method of the cathodic protected CFRP-SMA concrete component according to claim 1, characterized in that: The insulating member comprises: A yellow wax tube, sleeved on the longitudinal reinforcement; An insulating rubber layer, one side of the insulating rubber layer is connected to the yellow wax tube, and the other side of the insulating rubber layer is connected to the fiber-reinforced composite layer.

5. A method for preparing a cathodic protected CFRP-SMA concrete component, characterized in that: The method for preparing the cathodically protected CFRP-SMA concrete component is used to prepare the cathodically protected CFRP-SMA concrete component as claimed in any one of claims 1 to 4, comprising the following steps: Obtaining the cross-sectional dimensions of the cathodic protected CFRP-SMA concrete component, the specification and quantity of the longitudinal reinforcement, and the arrangement of the composite stirrups; According to the cross-sectional dimensions and the specification quantities, the provided plurality of longitudinal bars are formed into an initial reinforcement cage; According to the arrangement, the prepared composite stirrups are wound around the outside of the plurality of longitudinal bars through the insulating member to obtain a target steel cage; After the positive electrode of the provided power source is connected to the fiber reinforced composite layer of the composite stirrup and the negative electrode of the power source is connected to the longitudinal reinforcement, the provided concrete is poured into the target reinforcement cage to obtain a cathodically protected CFRP-SMA concrete component.

6. The method for preparing a cathodic protected CFRP-SMA concrete component according to claim 5, characterized in that: According to the arrangement, the prepared composite stirrups are wound around the outside of the plurality of longitudinal bars through the insulating member to obtain a target steel cage, which specifically includes: Applying prestress to the provided shape memory metal strip for cold drawing to obtain a memory metal layer; The insulating layer is sheathed on the outer side of the memory metal layer, and a fiber-reinforced composite layer is sheathed on the outer side of the insulating layer to obtain a composite stirrup; According to the arrangement, the composite stirrups are wound around different positions outside the plurality of longitudinal bars through the plurality of insulating members.

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