A method for designing the surface form of a high-bonding-performance composite fiber tendon and a composite fiber tendon

Abstract

This invention discloses a method for designing the surface morphology of composite fiber reinforced polymer (FRP) bars with high bonding performance, and the FRP bars themselves. The method includes: S1, establishing a parametric model to simulate the behavior of the fiber reinforced polymer (FRP)-concrete interface based on the application environment requirements, including high-voltage electromagnetic environments and / or humid heat and corrosion environments; S2, constructing a composite surface morphology scheme with multiple rib structures of different functional orientations embedded in the FRP bar body based on the parametric model; S3, quantitatively analyzing the microscopic characteristics of the composite surface morphology scheme, and iteratively optimizing it with the objective functions of maximizing bond strength and minimizing crack width, considering temperature gradient and load coupling effects, to obtain the optimized geometric parameters of the composite surface morphology. This invention enables precise quantitative design of the surface geometric parameters of FRP bars and constructs a composite surface morphology scheme with multiple rib structures of different functional orientations embedded in the FRP bar body.

Description

Technical Field

[0001] This invention belongs to the field of application technology of fiber-reinforced composite materials in civil and power engineering structures. Specifically, it relates to a method for designing the surface form of fiber reinforcement with high bonding performance and composite fiber reinforcement, which is particularly suitable for concrete structures in complex environments of high voltage electromagnetic fields and coastal humid heat, especially power infrastructure such as reactor foundations, substation foundations and power transmission and transformation tower foundations in coastal areas. Background Technology

[0002] In the construction of power infrastructure, reactor foundations serve as a key supporting structure, and their stability and durability directly affect the safe operation of the power grid.

[0003] Traditional reinforced concrete foundations are susceptible to eddy current effects in high-voltage electromagnetic field environments, leading to problems such as heat loss, material degradation, and crack propagation. Meanwhile, in humid coastal environments, foundations are prone to chloride ion erosion and salt corrosion, resulting in steel corrosion and reduced concrete durability.

[0004] To address these issues, fiber-reinforced polymer (FRP) bars have been introduced as an alternative material, offering advantages such as low electrical conductivity, low magnetic permeability, corrosion resistance, and lightweight yet high strength. However, the interfacial bond performance between existing FRP bars and concrete remains insufficient, primarily manifested in the following ways:

[0005] Smooth or simple textured surfaces result in low bond strength, making the foundation prone to interfacial slippage, pull-out failure, or concrete splitting under dynamic loads induced by high-pressure electromagnetic gradients or in humid coastal conditions, thus affecting the foundation's bearing capacity and long-term stability.

[0006] Furthermore, existing FRP rib surface treatment methods mainly include sanding, spiral winding, or simple rib texture. While these methods can improve mechanical interlocking, they lack systematic design and cannot fully consider fiber type, volume fraction, rib diameter, and multi-scale coupling effects, resulting in uneven bonding efficiency and difficulty in quantitative optimization. Especially in high-voltage electromagnetic environments, eddy current-induced thermal gradients further amplify interfacial stress concentration; in humid coastal environments, high humidity and salt erosion accelerate material degradation, and existing surface treatments are insufficient to effectively suppress crack propagation and durability decline.

[0007] Therefore, there is an urgent need for a surface design method for fiber reinforcement with high bonding performance to significantly improve interfacial bonding strength, control cracks, and extend service life, so as to meet the dual challenges of high-voltage electromagnetic environment and coastal humid heat. Summary of the Invention

[0008] To address the aforementioned technical problems, the purpose of this invention is to provide a surface morphology design method for fiber-reinforced polymer (FRP) bars with high bonding performance. This method solves the technical challenges of insufficient bond strength, easy axial slippage, interfacial shear failure, and poor long-term durability of existing FRP bar-concrete interfaces under the dual environments of high-pressure electromagnetic field-induced eddy current thermal effect and coastal humid salt spray corrosion. It enables precise quantitative design of the FRP bar surface geometry parameters, constructing a composite surface morphology scheme with multiple rib structures of different functional orientations embedded in the fiber bar body. This composite surface morphology scheme with multiple rib structures can form a multi-layered, multi-directional mechanical anchoring and friction damping system, ensuring interfacial stability under high-pressure electromagnetic eddy current thermal gradient (10-50 A / m²) and coastal humid salt spray (90% humidity, chloride ion concentration >500 mg / L) environments.

[0009] To achieve the above-mentioned technical objectives, the present invention employs the following technical means:

[0010] A method for designing the surface form of high-bonding-performance composite fiber reinforcement includes the following steps:

[0011] Step S1, Design Parameter Determination: Based on the application environment requirements of fiber reinforcement, establish a parameterized model for simulating the behavior of the fiber reinforcement-concrete interface. The application environment requirements include high-voltage electromagnetic environment and / or humid heat and corrosion environment. Step S2, Composite Surface Morphology Construction: Based on the parameterized model, construct a composite surface morphology scheme containing multiple rib structures with different functional orientations on the fiber rib body; Step S3, Surface morphology optimization: The microscopic characteristics of the composite surface morphology scheme are quantitatively analyzed, and iterative optimization is performed with the objective functions of maximizing the bonding strength and minimizing the crack width, taking into account the temperature gradient and load coupling effect, to obtain the optimized composite surface morphology geometric parameters, ensuring that the optimized composite surface morphology meets the bonding performance requirements.

[0012] Beneficial effects: By optimizing the surface morphology of the fiber reinforcement and designing a multi-layered mechanical interlocking and friction damping system, the bond strength between the fiber reinforcement and concrete can be enhanced, thereby improving its adaptability and corrosion resistance in extreme temperature, humidity, and corrosive environments. This surface optimization design effectively reduces thermal stress concentration, increases the friction coefficient, and inhibits the penetration of corrosive media, thus enhancing its stability and long-term durability, ensuring the reliability of the fiber reinforcement in high-temperature, low-temperature, and harsh environments.

[0013] Compared to traditional surface treatment methods, the surface design method employed in this invention has lower production costs. Through reasonable rib structure design and geometric parameter optimization, not only is performance improved, but reliance on expensive coatings or additional processing steps is reduced, thereby lowering overall production costs.

[0014] The surface design method of this invention can be manufactured using conventional fiber reinforcement production processes, without the need for complex additional surface treatment. The design method is compatible with existing production equipment, facilitating large-scale application and reducing technical difficulties and time costs during construction, thus improving construction efficiency.

[0015] The design method of this invention is not only applicable to traditional concrete structures, but also to different types of structures (such as those in the power industry and building structures), demonstrating excellent flexibility and applicability. Whether in high-voltage power grid facilities or conventional building structures, it effectively improves bonding performance and extends the service life of the structure.

[0016] This invention, through reasonable structural design and optimized parameters, ensures the reliability of fiber reinforcement in complex environments, especially in environments with high loads and strong electromagnetic interference, and can effectively improve bonding strength to meet the high requirements of applications in the power, industrial and other fields.

[0017] Furthermore, in step S1, the parameterized model is established using finite element analysis software.

[0018] Furthermore, in step S2, the multiple rib structures include anti-slip annular ribs, cross-grid ribs, and circumferential support ribs arranged sequentially from the outside to the inside on the surface of the fiber reinforcement, wherein the fiber reinforcement body serves as the base.

[0019] The interlocking mesh ribs form an interwoven mesh structure to enhance mechanical engagement and stress distribution uniformity.

[0020] The circumferential support ribs are evenly spaced along the circumferential direction of the fiber reinforcement to provide continuous circumferential support and suppress axial slippage and thermal stress concentration.

[0021] The anti-slip annular rib enhances axial pull-out resistance and is used to improve the coefficient of friction;

[0022] The three elements work together to form a multi-layered, multi-directional mechanical anchoring and friction damping system.

[0023] Beneficial Effects: This invention significantly improves the bond strength between fiber-reinforced tendons and concrete by optimizing the surface structure of the tendons and employing a combination of cross-grid ribs, circumferential support ribs, and anti-slip ring ribs. The different types of rib structures work together to form a multi-layered mechanical interlocking system, which not only increases the surface roughness and friction of the tendons but also enhances their bond strength with concrete. The synergistic effect of these three structures improves the overall stability and load-bearing capacity of the structure, further enhancing its resistance to deformation and slippage. Specifically, the cross-grid ribs enhance the bond strength between the tendons and concrete, the circumferential support ribs provide circumferential support, effectively suppressing structural deformation caused by thermal stress, and the anti-slip ring ribs increase axial pull-out resistance and frictional damping. These structures functionally support each other, and through optimized combination, they produce better technical effects, improving the overall structural stability, load-bearing capacity, and durability.

[0024] Furthermore, in step S2, the geometric parameters of the cross-grid ribs include the height of the cross-grid ribs. ,spacing and density Based on the theory of interfacial shear stress distribution, the following is determined:

[0025] The height h of the cross-grid ribs g It can be obtained through the following formula:

[0026] ,

[0027] in, The diameter of the fiber reinforcement. The empirical correction factor is (0.5-1.0). This represents the peak interfacial shear stress. For reference shear stress, For temperature gradient, The critical temperature gradient;

[0028] The spacing of the cross mesh ribs It can be obtained through the following formula:

[0029] ,

[0030] in, The adjustment factor is (0.5-1.0). For fiber elastic modulus, This represents the fiber volume fraction. Poisson's ratio, For the interface shear modulus, The coefficient of friction;

[0031] The unit length grid density It can be obtained through the following formula:

[0032] ,

[0033] in, The grid density per unit length For the number of grid cells, For characteristic length, The scaling factor is (1.0-2.0). For normal stress, Porosity is the coefficient of thermal expansion.

[0034] Furthermore, the geometric parameters of the anti-slip annular rib include the height of the anti-slip annular rib. ,width and interval distance Based on the Mohr-Coulomb friction theory and the principle of pull-out energy dissipation, it is determined that,

[0035] Height of anti-slip ring rib It can be obtained through the following formula:

[0036] ,

[0037] in, The height ratio coefficient is (0.3-0.5). For equivalent frictional force, The elastic modulus of the matrix;

[0038] The anti-slip annular rib width w r It can be obtained through the following formula:

[0039] ,

[0040] in, This is the width correction factor, ranging from 0.3 to 0.5. Salt concentration, Where is the diffusion coefficient. The critical strain;

[0041] The anti-slip annular rib spacing distance It can be obtained through the following formula:

[0042] ,

[0043] in, This is the spacing adjustment coefficient, ranging from 1.0 to 2.0. To design the pull-out force, is the damping coefficient.

[0044] Furthermore, the geometric parameters of the circumferential support rib include the height of the circumferential support rib. The number of circumferential support ribs n around the fiber reinforcement s Based on Timoshenko beam theory and the principle of circumferential stiffness balance, the following is determined:

[0045] The height of the circumferential support rib It can be obtained through the following formula:

[0046] ,

[0047] in, To support the height coefficient (0.5-1.0), For thermally induced bending moment, For the load bending moment, This represents the elastic modulus of the fiber reinforcement. The second moment of inertia of the fiber reinforcement section. Let be the radius of curvature.

[0048] Number of circumferential support ribs around the fiber reinforcement It can be obtained through the following formula:

[0049] ,

[0050] in, The quantity adjustment coefficient is set between 4 and 8. For the target support spacing, For circumferential stiffness, For axial stiffness.

[0051] Beneficial Effects: The design of this invention considers the adaptability to different fiber rebar diameters and concrete structures. By adjusting parameters such as rib height, rib spacing, and rib density, this surface form design method can be widely applied to different types of fiber rebars and concrete foundation structures. This optimized design ensures that the bond between the fiber rebar and concrete remains stable under various load and environmental conditions.

[0052] Furthermore, the iterative optimization is a response surface methodology, and its objective function is:

[0053] ,

[0054] in, , , These are the weighting coefficients, and their sum is 1. The width of the crack; This represents the aging and degradation rate.

[0055] Furthermore, after step S3, the method further includes: S4: Based on the optimized composite surface morphology geometric parameters, establish a bond-slip constitutive model, and verify the effectiveness of the bond-slip constitutive model or the optimized composite surface morphology geometric parameters through a pull-out test.

[0056] Furthermore, the specimen for the pull-out test is a composite specimen formed by casting fiber reinforcement into a concrete block. After curing under standard conditions for 28 days, a monotonic loading test is performed at a loading rate of 0.5 mm / min.

[0057] Furthermore, after step S4, the method further includes: step S5: using sanding, spiral winding, or nano-coating processes to process and form a composite surface morphology on the fiber reinforcement surface according to the optimized composite surface morphology geometric parameters.

[0058] The present invention further discloses a composite fiber reinforcement whose surface morphology is designed by the aforementioned high-bonding-performance composite fiber reinforcement surface morphology design method. The fiber reinforcement surface has a composite surface morphology containing multiple functional ribs, and the geometric parameters of the composite surface morphology are optimized to make the fiber reinforcement suitable for high-voltage electromagnetic and / or humid heat corrosion environments. Attached Figure Description

[0059] Figure 1 This is a flowchart illustrating a method for designing the surface form of fiber reinforcement with high bonding performance, as provided in an embodiment of this application.

[0060] Figure 2 A schematic diagram of the surface structure of a fiber reinforcement surface form design method with high bonding performance provided in this application embodiment; in the figure: 1-fiber reinforcement body; 2-anti-slip annular rib; 3-cross mesh rib; 4-circumferential support rib. Detailed Implementation

[0061] To enable those skilled in the art to better understand the present application, the following will refer to the accompanying drawings in the embodiments of the present application (…). Figures 1-2 The technical solutions in the embodiments of this application are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of this application.

[0062] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that comprises a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product or device.

[0063] This invention provides a method for designing the surface form of fiber-reinforced reinforcing bars with high bonding performance, using carbon fiber FRP bars, glass fiber FRP bars, and basalt fiber FRP bars as substrates, but is not limited to these. It is applicable to the application of other fiber-reinforced composite reinforcing bars in high-voltage electromagnetic and coastal humid and hot environments. Combined with... Figures 1-2 As shown, the specific implementation steps of the method of the present invention are as follows:

[0064] like Figure 1 The methods shown include:

[0065] Step S1: Determine design parameters

[0066] The module for determining design parameters takes fiber type, volume fraction, diameter, and application environment (high-voltage electromagnetic field strength of 10-50 A / m² and coastal humid and hot conditions with humidity of 90% and chloride ion concentration >500 mg / L) as input. The output is a parametric model and initial thresholds.

[0067] The operation first collects the mechanical properties of the fiber material (such as elastic modulus and coefficient of thermal expansion) and environmental parameters (such as eddy current heat source Q=σ· Where σ is the conductivity and E is the electric field strength; the salt spray diffusion equation is ∂C / ∂t = D·∇²C, where D is the diffusion coefficient and C is the chloride ion concentration.

[0068] Finite element analysis software was used to simulate interfacial bonding behavior, with a mesh density of 2000 nodes / m². The initial threshold ranges for surface roughness Ra, porosity φ, and friction coefficient μ were calculated. The simulation process considered multiphysics coupling (electromagnetic-thermal-mechanical), with a temperature gradient ranging from -20℃ to 80℃. The model accuracy was verified through mesh convergence testing (error <2%). Results showed that the initial roughness threshold was optimized to 1.5–2.5 μm, and the friction coefficient threshold to 0.5–0.8, reducing parameter uncertainty by 20% compared to traditional empirical designs, providing a reliable foundation for subsequent morphology construction.

[0069] Step S2: Construction of composite surface morphology

[0070] Implement the composite surface morphology construction module, with the parameterized model output from step S1 as the input and the initial composite surface morphology design as the output.

[0071] The operation is based on a model, and anti-slip annular ribs, cross-grid ribs, and circumferential support ribs are sequentially set on the surface of the fiber reinforcement from the outside to the inside, with the fiber reinforcement body as the matrix, such as... Figure 2 As shown, 1 is the main fiber reinforcement, 2 is the anti-slip ring rib, 3 is the cross mesh rib, and 4 is the circumferential support rib.

[0072] Calculate the parameters of each rib using the key formula: the height h of the intersecting mesh ribs. g Spacing s g and density ρ g Determined based on the theory of interfacial shear stress distribution and the Saint-Venant principle;

[0073] The height h of the cross-grid ribs g It can be obtained through the following formula:

[0074] ,

[0075] in, The height of the intersecting grid ribs, The diameter of the fiber reinforcement. The empirical correction factor is (0.5-1.0). This represents the peak interfacial shear stress. For reference shear stress, For temperature gradient, The critical temperature gradient;

[0076] The spacing s of the intersecting grid ribs g It can be obtained through the following formula:

[0077] ,

[0078] in, The adjustment factor is (0.5-1.0). For fiber elastic modulus, This represents the fiber volume fraction. Poisson's ratio, For the interface shear modulus, The coefficient of friction;

[0079] The unit length grid density It can be obtained through the following formula:

[0080] ,

[0081] in, The grid density per unit length For the number of grid cells, For characteristic length, The scaling factor is (1.0-2.0). For normal stress, Porosity is the coefficient of thermal expansion.

[0082] Height of anti-slip ring rib ,width and interval distance Determined based on the Mohr-Coulomb friction theory and the principle of pull-out energy dissipation;

[0083] The height h of the anti-slip ring rib r It can be obtained through the following formula:

[0084] ,

[0085] in, The height ratio coefficient is (0.3-0.5). For equivalent frictional force, The elastic modulus of the matrix;

[0086] The width of the anti-slip annular rib It can be obtained through the following formula:

[0087] ,

[0088] in, This is the width correction factor, ranging from 0.3 to 0.5. Salt concentration, Where is the diffusion coefficient. The critical strain;

[0089] The anti-slip annular rib spacing distance It can be obtained through the following formula:

[0090] ,

[0091] in, This is the spacing adjustment coefficient, ranging from 1.0 to 2.0. To design the pull-out force, is the damping coefficient.

[0092] Height of circumferential support ribs And the number of ribs per week Determined based on Timoshenko beam theory and the principle of circumferential stiffness balance.

[0093] The height of the circumferential support rib It can be obtained through the following formula:

[0094] ,

[0095] in, To support the height coefficient (0.5-1.0), For thermally induced bending moment, For the load bending moment, This represents the elastic modulus of the fiber reinforcement. The second moment of inertia of the fiber reinforcement section. Let be the radius of curvature.

[0096] The number n of circumferential support ribs around the fiber reinforcement s It can be obtained through the following formula:

[0097] ,

[0098] in, The quantity adjustment coefficient is set between 4 and 8. For the target support spacing, For circumferential stiffness, For axial stiffness.

[0099] The parameter is set as an empirical coefficient. =0.5-1.0, adjustment coefficient =0.5-1.0, proportionality coefficient =1.0-2.0, etc., and the calculation iterations were performed 10 times to ensure that the morphology met the requirements of multi-level anchoring. The result is a multi-directional mechanical interlocking system, which improves the axial pull-out resistance and reduces the thermal stress concentration by 15%. The verification was passed by finite element simulation (stress distribution uniformity >95%).

[0100] This invention considers the compatibility with different fiber rebar diameters and concrete structures. By adjusting parameters such as rib height, rib spacing, and rib density, this surface design method can be widely applied to different types of fiber rebars and concrete foundation structures. This optimized design ensures that the bond between the fiber rebar and concrete remains stable under various load and environmental conditions.

[0101] Step S3: Microscopic morphology analysis and optimization

[0102] The microstructure analysis and optimization module is implemented, with the initial structure design as input and the optimized surface parameters as output. The operation employs scanning electron microscopy (SEM, Hitachi SU8220, resolution 1-10 nm) and atomic force microscopy (AFM, Bruker Dimension Icon, vertical resolution 0.1 nm) to perform three-dimensional imaging and quantification of the surface structure, extracting roughness, porosity, and coefficient of friction.

[0103] The optimization process iterates parameters using the response surface methodology (RSM) combined with Box-Behnken design (BBD), with the objective function being: (weighting coefficient) =0.4、 =0.3、 =0.3), The width of the crack; This represents the aging and degradation rate.

[0104] Considering the temperature gradient and load coupling effect, the number of iterations is 20, and the optimization accuracy R²>0.95.

[0105] If the indicators do not meet the requirements, return to step S2 to rebuild. The result is that the roughness is optimized to 2.0±0.15 μm, the porosity is <3%, and the friction coefficient is improved to 0.75, which is 18% higher than the initial design target for bond strength.

[0106] Step S4: Establishment and verification of the bond-slip constitutive relation

[0107] The module for establishing and verifying the bond-slip constitutive relationship is implemented. The input is optimized morphology parameters, and the output is a verification model. The operation constructs a bilinear bond-slip model based on the optimized morphology, describing the nonlinear relationship between interfacial shear stress and local slip, and considering viscoelastic corrections to simulate creep and salt spray degradation. The model parameters are set as the initial shear modulus G and the elastic slip limit s. e Peak bond stress τ max and limit slip s u The model was validated through pull-out tests: specimens of different fiber types (100mm×100mm×150mm) were selected, cured for 28 days after concrete pouring (temperature 23℃±2℃, humidity 95%±5% RH), and monotonic loading was applied using a universal testing machine (loading rate 0.5 mm / min). The load-displacement curves were recorded, and the tests were repeated for 3 sets. The error control was <5%; if it exceeded the threshold, the model was returned to S3 for further optimization. The model accuracy was >95%, validating the interface stability under dual environments.

[0108] Step S5: Implementation of surface treatment process

[0109] The surface treatment process implementation module takes an optimized model as input and outputs the final surface morphology. The operation employs sanding (particle size 50-100 μm, pressure 0.5 MPa), spiral winding (pitch 5-10 mm, speed 0.2 m / s), and nano-coating (thickness 10-20 nm, spraying pressure 0.3 MPa) processes to achieve a composite morphology, with a processing time of 30 minutes / meter. Aging tests are conducted, including 1000 hours in an environment of 40°C, 90% humidity, and 500 mg / L salt spray concentration. The attenuation rate is assessed using a contact angle meter and adhesion tester, with a value <10%. Results ensure adhesion durability, with a repeatability standard deviation of <5% for failure mode analysis (pull-out, splitting, shear).

[0110] like Figure 1 The methods shown include:

[0111] Design of the main body of the fiber reinforcement:

[0112] The fiber-reinforced core is constructed, with fiber material as input and a matrix structure as output. Carbon fiber, glass fiber, or basalt fiber are selected as the core material, with a volume fraction of 45%-55% and a diameter of 8-16 mm. The core is prepared using a pultrusion molding process (temperature 180℃, pulling speed 0.5 m / min), ensuring a core strength >500 MPa and corrosion resistance meeting GB / T 50608 standards.

[0113] Design of the anti-slip ring rib section:

[0114] The anti-slip annular rib section is implemented. The input is the fiber optic main body, and the output is a fiber optic structure with an anti-slip annular rib layer. The anti-slip annular rib is added through a spiral winding process, with a height h. r =0.3-0.5 cm, width w r =0.3-0.5 mm, interval i r =1.0-2.0 cm, ensuring a 20% increase in the coefficient of friction.

[0115] Design of the cross-grid rib section:

[0116] The cross-grid rib section is implemented. The input is fiber optic ribs with anti-slip annular rib layers, and the output is a fiber optic rib structure with anti-slip annular rib layers and cross-grid ribs. The operation uses a mesh forming mold, with a high... =0.5-1.0 mm, spacing =0.5-1.0 cm, density =4-8 units per unit length to ensure stress distribution uniformity >90%.

[0117] Design of the circumferential support rib section:

[0118] The circumferential support rib section is implemented. The input is a fiber optic rib with an anti-slip annular rib layer and cross-grid ribs, and the output is a fiber optic rib structure with an anti-slip annular rib layer, cross-grid ribs, and circumferential support ribs. The operation involves adding circumferential support ribs using an annular molding die, with a height... =0.5-1.0 mm, number of circumferential support ribs around the fiber reinforcement =4-8, ensuring thermal stress suppression rate >15%.

[0119] Example 1: Surface design for carbon fiber FRP reinforcement.

[0120] The design parameters for S1 were determined. A model was established based on the carbon fiber type, volume fraction of 50%, rib diameter of 12 mm, and application environment to simulate and calculate the initial threshold.

[0121] S2 composite surface morphology construction. A three-layer rib structure is set, such as... Figure 2 As shown, the parameters are calculated using the formula.

[0122] S3 Microscopic morphology analysis and optimization. Analyze and iteratively optimize, then return to step S2 if adjustments are needed.

[0123] S4 Establishment and verification of the bond-slip constitutive relationship. Construct and verify the model. If the calculation error of the experimental results exceeds 5%, return to step S3.

[0124] S5 surface treatment process implemented. Morphology achieved and aging tests conducted.

[0125] In this embodiment, the bonding strength of the carbon fiber FRP reinforcement is improved, making it suitable for high-voltage electromagnetic environments.

[0126] Example 2: Surface design for glass fiber FRP ribs.

[0127] Similar to Example 1, but with glass fiber, 48% volume fraction, and 8 mm diameter, to optimize resistance to damp heat corrosion.

[0128] Example 3: Surface design for basalt fiber FRP reinforcement.

[0129] Similar to Example 1, but modified to use basalt fiber with a volume fraction of 55% and a diameter of 16 mm to improve load-bearing capacity.

[0130] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, specific embodiments have been described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than that shown in the embodiments and still achieve the desired result. Additionally, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0131] The above description is only a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

[0132] This specification and accompanying drawings are merely illustrative examples of this application and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Therefore, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.

Claims

1. A method for designing the surface form of high-bonding-performance composite fiber reinforcement, characterized in that, Includes the following steps: Step S1, Design Parameter Determination: Based on the application environment requirements of fiber reinforcement, establish a parameterized model for simulating the behavior of the fiber reinforcement-concrete interface. The application environment requirements include high-voltage electromagnetic environment and / or humid heat and corrosion environment. Step S2, Composite Surface Morphology Construction: Based on the parameterized model, construct a composite surface morphology scheme containing multiple rib structures with different functional orientations on the fiber rib body; Step S3, Surface morphology optimization: The microscopic characteristics of the composite surface morphology scheme are quantitatively analyzed, and iterative optimization is performed with the objective functions of maximizing the bonding strength and minimizing the crack width, taking into account the temperature gradient and load coupling effect, to obtain the optimized composite surface morphology geometric parameters, ensuring that the optimized composite surface morphology meets the bonding performance requirements.

2. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 1, characterized in that, In step S1, the parameterized model is established using finite element analysis software.

3. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 1, characterized in that, In step S2, the multiple rib structures include anti-slip annular ribs, cross-grid ribs, and circumferential support ribs arranged sequentially from the outside to the inside on the surface of the fiber reinforcement, wherein the fiber reinforcement body serves as the base. The anti-slip annular rib enhances axial pull-out resistance and is used to improve the coefficient of friction; The interlocking mesh ribs form an interwoven mesh structure to enhance mechanical engagement and stress distribution uniformity. The circumferential support ribs are evenly spaced along the circumferential direction of the fiber reinforcement to provide continuous circumferential support and suppress axial slippage and thermal stress concentration. The three elements work together to form a multi-layered, multi-directional mechanical anchoring and friction damping system.

4. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 3, characterized in that, In step S2, the geometric parameters of the cross-grid ribs include the height of the cross-grid ribs. ,spacing and density Based on the theory of interfacial shear stress distribution, the following is determined: The height of the cross-grid ribs It can be obtained through the following formula: ， in, The diameter of the fiber reinforcement. The empirical correction factor is set between 0.5 and 1.

0. This represents the peak interfacial shear stress. Reference shear stress; For temperature gradient; The critical temperature gradient; The spacing of the cross mesh ribs It can be obtained through the following formula: ， in, Adjustment factor (0.5-1.0); It is the fiber's elastic modulus; This represents the fiber volume fraction. Poisson's ratio; For interface shear modulus; The coefficient of friction; The unit length grid density It can be obtained through the following formula: ， in, The grid density per unit length; Number of grid cells; The characteristic length of the intersecting mesh ribs; This is a proportionality coefficient, ranging from 1.0 to 2.0; Normal stress; Porosity; is the coefficient of thermal expansion.

5. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 3, characterized in that, The geometric parameters of the anti-slip annular rib include the height of the anti-slip annular rib. ,width and interval distance Based on the Mohr-Coulomb friction theory and the principle of pull-out energy dissipation, it is determined that, Height of anti-slip ring rib It can be obtained through the following formula: ， in, The height ratio coefficient is (0.3-0.5). For equivalent frictional force, The elastic modulus of the matrix; The width of the anti-slip annular rib It can be obtained through the following formula: ， in, This is the width correction factor, ranging from 0.3 to 0.

5. Salt concentration, Where is the diffusion coefficient. The critical strain; The anti-slip annular rib spacing distance It can be obtained through the following formula: ， in, This is the spacing adjustment coefficient, ranging from 1.0 to 2.

0. To design the pull-out force, is the damping coefficient.

6. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 3, characterized in that, The geometric parameters of the circumferential support rib include the height of the circumferential support rib. Number of circumferential support ribs around the fiber reinforcement Based on Timoshenko beam theory and the principle of circumferential stiffness balance, the following is determined: The height of the circumferential support rib It can be obtained through the following formula: ， in, To support the height coefficient (0.5-1.0), For thermally induced bending moment, For the load bending moment, This represents the elastic modulus of the fiber reinforcement. The second moment of inertia of the fiber reinforcement section. The radius of curvature; Number of circumferential support ribs around the fiber reinforcement It can be obtained through the following formula: ， in, The quantity adjustment coefficient is set between 4 and 8. For the target support spacing, For circumferential stiffness, For axial stiffness.

7. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 1, characterized in that, The iterative optimization is a response surface methodology, and its objective function is: ， in, , , These are the weighting coefficients, and their sum is 1. The width of the crack; This represents the aging and degradation rate.

8. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 1, characterized in that, After step S3, the method further includes: S4: Based on the optimized composite surface morphology geometric parameters, establish a bond-slip constitutive model, and verify the effectiveness of the bond-slip constitutive model or the optimized composite surface morphology geometric parameters through a pull-out test.

9. The surface design method for high-bonding-performance composite fiber reinforcement according to claim 1, characterized in that, After step S4, the process further includes step S5: using sanding, spiral winding, or nano-coating processes to process a composite surface morphology on the fiber reinforcement surface according to the optimized composite surface morphology geometric parameters.

10. A composite fiber reinforcement, characterized in that, Its surface morphology is designed by the high-bonding-performance composite fiber reinforcement surface morphology design method according to any one of claims 1 to 9, wherein the fiber reinforcement surface has a composite morphology containing multiple functional ribs, and the geometric parameters of the composite morphology are optimized to make the fiber reinforcement suitable for high-voltage electromagnetic and / or humid heat corrosion environments.

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