Sulfur concrete steel bar bonding anticorrosion structure and preparation method

Abstract

This invention discloses a sulfur-bonded anti-corrosion structure for reinforced concrete and its preparation method. Through the chemical bonding effect of the sacrificial anode anti-corrosion layer and the bonding layer, the mechanical interlocking effect of the rough surface of the reinforced concrete, and the interface densification achieved by preheating and synergistic casting, the interface bonding strength reaches ≥3.0 MPa, an improvement of over 60% compared to traditional processes, effectively solving problems such as debonding and hollowing. The sacrificial anode anti-corrosion layer provides dual protection functions of physical shielding and electrochemical protection. Even if the coating is partially damaged, the reinforced concrete can still be protected through the sacrificial anode effect, fundamentally preventing electrochemical corrosion between the reinforced concrete and sulfur. The anti-corrosion life is more than twice that of traditional processes, making it suitable for harsh environments such as chemical plants and high-salt-spray environments. The coating application and preheating casting processes are simple to operate, requiring no complex equipment, and can meet the needs of rapid setting and early strength projects. It is applicable to various engineering scenarios such as roads, bridges, hydraulic structures, and chemical industrial park floors.

Description

Technical Field

[0001] This invention relates to the field of concrete construction technology, and in particular to a sulfur concrete steel reinforcement bonding and corrosion protection structure and its preparation method. Background Technology

[0002] Sulfur concrete, with its rapid setting and early strength, corrosion resistance and impermeability, as well as its ability to be constructed at room temperature without curing, has become the preferred material for the rapid repair of damaged concrete structures and is widely used in engineering fields such as roads, bridges, and hydraulic structures.

[0003] In existing technologies, there are many drawbacks when sulfur concrete is used in combination with steel bars: under traditional processes, the two rely only on simple mechanical interlocking, and the bond strength is usually less than 2.0 MPa. Under load, debonding and hollowing are prone to occur, which affects the overall stability of the structure. Elemental sulfur is prone to electrochemical reaction with steel bars, which can cause steel bar corrosion. The corroded steel bars expand in volume, further damaging the interface bond and causing the sulfur concrete layer to crack and fall off.

[0004] Existing solutions only apply a single anti-corrosion coating to the reinforcing bars or make simple modifications to the sulfur concrete, which can only solve one problem of corrosion or adhesion and cannot achieve a dual effect. Some processes that use preheated reinforcing bars before pouring can improve the initial adhesion effect, but they do not solve the problem of direct contact between sulfur and reinforcing bars. With long-term use, reinforcing bar corrosion is still likely to occur, and the improvement in interfacial bond strength is limited. Summary of the Invention

[0005] This invention provides a sulfur-reinforced concrete steel reinforcement bonded anti-corrosion structure and its preparation method to overcome the above-mentioned technical problems.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: A sulfur concrete steel reinforcement bonding and corrosion protection structure includes: a sacrificial anode corrosion protection layer, a bonding layer, a modified sulfur concrete layer, and a surface hydrophobic / anti-icing coating sequentially disposed on the steel reinforcement body; The modified sulfur concrete layer is composed of industrial sulfur, bio-based composite modifier, solid waste activated aggregate and fly ash.

[0007] Furthermore, the sacrificial anode anti-corrosion layer is composed of zinc powder, rust inhibitor, silane coupling agent and substrate, wherein the substrate is cement slurry or epoxy resin; The silane coupling agent accounts for 3% to 5% of the substrate mass, the rust inhibitor accounts for 4% of the substrate mass, and the zinc powder accounts for 8% to 12% of the total mass of the sacrificial anode anti-corrosion layer.

[0008] Furthermore, the zinc powder has a particle size of 80–120 mesh.

[0009] Furthermore, the thickness of the sacrificial anode anti-corrosion layer is 30–50 μm.

[0010] Furthermore, the adhesive layer is composed of epoxy resin, curing agent and sulfur powder in a mass ratio of 100:30-40:10-15, and the thickness of the adhesive layer is 50-100 μm.

[0011] Furthermore, the modified sulfur concrete layer is composed of industrial sulfur, bio-based composite modifier, solid waste activated aggregate and Class I fly ash in a mass ratio of 20-25:1-1.5:65-70:5-8. The activated solid waste aggregate is composed of steel slag, waste ceramic fragments and recycled concrete fragments in a mass ratio of 4:3:3. The moisture content of the activated solid waste aggregate is <0.5%, and the particle sizes of the steel slag, waste ceramic fragments and recycled concrete are 5-20 mm, 2-5 mm and 0.5-2 mm, respectively.

[0012] Furthermore, the bio-based composite modifier is composed of a ternary compound of polyolefin modifier, bio-based polymer, and nano-silica; The mass ratio of the polyolefin modifier, the bio-based polymer, and the nano-silica is 4-6:2-4:1-2; The bio-based polymer is one or a combination of two of the following: lignin sulfonate modified product and rosin resin.

[0013] Furthermore, the thickness of the surface hydrophobic / anti-icing coating is 30-50 μm, and it is composed of a mixture of resin and nano-silica. The mass of nano-silica accounts for 5%-8% of the total mass of the surface hydrophobic / anti-icing coating, and the resin is a fluorinated resin or an organosilicon resin.

[0014] A method for preparing a sulfur-reinforced concrete reinforced steel anti-corrosion structure, comprising the following steps: S1: Remove rust and oil from the steel reinforcement body, blow away surface slag and dust, and control the surface roughness Ra to 12.5~25μm; S2: Apply a sacrificial anode anti-corrosion layer and an adhesive layer sequentially to the steel reinforcement body, with the total coating thickness controlled between 80 and 150 μm; S3: After mixing solid waste activated aggregate with fly ash, molten industrial sulfur and bio-based composite modifier are added and stirred to obtain modified sulfur concrete. S4: Preheat the steel bar body coated with sacrificial anode anti-corrosion layer and bonding layer to 40-60℃, pour modified sulfur concrete and vibrate it lightly at low frequency to form a modified sulfur concrete layer. S5: After the modified sulfur concrete layer has cooled naturally to room temperature; S6: Apply a hydrophobic / anti-icing coating to the modified sulfur concrete layer by roller coating or spraying.

[0015] Furthermore, step S6 is also included: when the modified sulfur concrete layer needs to be repaired, if the repair depth is >50mm, it is poured in layers with each layer having a thickness of ≤30mm. Before pouring the upper layer, the surface of the lower layer is roughened and preheated to 40-50℃, and a 10-20μm thick sulfur modified epoxy adhesive is applied.

[0016] Beneficial effects: This invention provides a sulfur-bonded anti-corrosion structure for reinforced concrete and its preparation method. Through the chemical bonding effect of the sacrificial anode anti-corrosion layer and the bonding layer, the mechanical interlocking effect of the rough surface of the reinforced concrete, and the interface densification achieved by preheating and synergistic casting, the interface bond strength reaches ≥3.0 MPa, an improvement of over 60% compared to traditional processes, effectively solving problems such as debonding and hollowing. The sacrificial anode anti-corrosion layer achieves dual protection functions of physical shielding and electrochemical protection. Even if the coating is partially damaged, the reinforced concrete can still be protected through the sacrificial anode effect, fundamentally preventing electrochemical reactions between the reinforced concrete and sulfur. The modified sulfur concrete exhibits superior corrosion resistance, extending its service life by more than two times compared to traditional processes. It is suitable for harsh environments such as chemical plants and high-salt-spray environments. The modified sulfur concrete layer utilizes industrial or construction solid waste materials to replace natural aggregates, achieving high-value utilization and full-component utilization of solid waste, thus solving the problems of land occupation and environmental pollution caused by solid waste dumping. The coating and preheating pouring processes are simple to operate and require no complex equipment. The preparation of modified sulfur concrete is similar to that of traditional processes, with comparable construction time. It can withstand the service load within 8 hours, meeting the requirements of rapid setting and early strength projects. It is suitable for various engineering scenarios such as roads, bridges, hydraulic structures, and chemical industrial park floors. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a sulfur concrete steel reinforcement bonding corrosion protection structure disclosed in this invention.

[0019] In the diagram: 1. Reinforcing steel body; 2. Sacrificial anode anti-corrosion layer; 3. Bonding layer; 4. Modified sulfur concrete layer; 5. Surface hydrophobic / anti-icing coating. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1 This embodiment provides a sulfur-reinforced concrete reinforced concrete anti-corrosion structure, such as... Figure 1 As shown, it includes: a sacrificial anode anti-corrosion layer 2, an adhesive layer 3, a modified sulfur concrete layer 4, and a surface hydrophobic / anti-icing coating 5, which are sequentially disposed on the steel reinforcement body 1; The modified sulfur concrete layer 4 is composed of industrial sulfur (purity ≥99.5%), bio-based composite modifier, solid waste activated aggregate and fly ash.

[0022] The sacrificial anode anti-corrosion layer 2 is tightly bonded to the steel reinforcement body 1, achieving dual anti-corrosion through physical shielding and electrochemical protection, inhibiting the corrosion of the steel reinforcement body 1 from the source. The bonding layer 3 forms a strong chemical bond with the sacrificial anode anti-corrosion layer 2 and the modified sulfur concrete layer 4, while filling the rough structure on the surface of the steel reinforcement and forming a mechanical bond with the concrete. The surface hydrophobic / anti-icing coating 5 covers the exposed outer surface of the modified sulfur concrete layer 4, forming a dense hydrophobic anti-icing barrier, preventing the penetration of water and de-icing agents, and preventing surface icing.

[0023] Specifically, the sacrificial anode anti-corrosion layer 2 is composed of zinc powder, rust inhibitor, silane coupling agent and substrate, wherein the substrate is cement slurry or epoxy resin; The silane coupling agent accounts for 3% to 5% of the substrate mass (the mass ratio of silane coupling agent to substrate is 3 to 5: 100), the rust inhibitor accounts for 4% of the substrate mass (the mass ratio of rust inhibitor to substrate is 1: 25), and the zinc powder accounts for 8% to 12% of the total mass of the sacrificial anode anti-corrosion layer 2. The zinc powder is uniformly dispersed in the coating to form a sacrificial anode system, so that the coating can achieve physical shielding through the substrate and rust inhibitor, and can also protect the steel bar body 1 through the electrochemical action of the sacrificial anode.

[0024] Specifically, the zinc powder has a particle size of 80–120 mesh.

[0025] Specifically, the thickness of the sacrificial anode anti-corrosion layer 2 is 30–50 μm.

[0026] Specifically, the adhesive layer 3 is composed of epoxy resin, curing agent and sulfur powder in a mass ratio of 100:30-40:10-15 (fineer sulfur powder can be selected). The thickness of the adhesive layer 3 is 50-100 μm. The adhesive layer 3 forms a strong chemical bond with the sacrificial anode anti-corrosion layer 2 and the modified sulfur concrete layer 4, while protecting the zinc powder in the sacrificial anode anti-corrosion layer 2 from direct corrosion by sulfur.

[0027] Specifically, the modified sulfur concrete layer is composed of industrial sulfur, bio-based composite modifier, solid waste activated aggregate and Class I fly ash in a mass ratio of 20-25:1-1.5:65-70:5-8. The activated solid waste aggregate is composed of steel slag, waste ceramic fragments and recycled concrete fragments in a mass ratio of 4:3:3. The moisture content of the activated solid waste aggregate is <0.5%. The particle sizes of the steel slag, waste ceramic fragments and recycled concrete are 5-20 mm, 2-5 mm and 0.5-2 mm, respectively, so that the solid waste aggregate is continuously graded.

[0028] In actual production, the steel slag, waste ceramic fragments and recycled concrete are mixed to form solid waste aggregate, which is then placed in a preheating kiln and preheated at 100~120℃ for 2~3 hours. At the same time, a silane coupling agent (the mass ratio of silane coupling agent to solid waste aggregate is 3~5:1000) is used for surface activation treatment. Preheating removes the internal moisture of the solid waste aggregate, and surface activation enhances the interfacial bonding force between the solid waste aggregate and the sulfur system.

[0029] Modified sulfur concrete layer 4 uses steel slag, waste ceramics, and recycled concrete fragments as aggregates. After preheating and surface activation treatment, sulfur's adhesive properties are used to bond the solid waste aggregates. Sulfur acts as a binder for the activated solid waste aggregates, undergoing a weak chemical reaction with the active components of the steel slag to improve interfacial strength. The activated solid waste aggregates and the sulfur system form a structure of "chemical bonding + mechanical interlocking," and the angular shape of the solid waste aggregates further enhances the mechanical interlocking effect.

[0030] Specifically, the bio-based composite modifier is composed of a ternary compound of a polyolefin modifier, a bio-based polymer, and nano-silica; The mass ratio of the polyolefin modifier, the bio-based polymer, and the nano-silica is 4-6:2-4:1-2; The bio-based polymer is one or a combination of two of lignin sulfonate modifiers or rosin resins, to replace traditional polyolefin petrochemical modifiers (the mass ratio of traditional polyolefin petrochemical modifiers to industrial sulfur is 30-40:100).

[0031] Specifically, the thickness of the surface hydrophobic / anti-icing coating 5 is 30-50 μm, and it is composed of a mixture of resin and nano-silica. The mass of nano-silica accounts for 5%-8% of the total mass of the surface hydrophobic / anti-icing coating 5, and the resin is a fluorinated resin or an organosilicon resin.

[0032] This embodiment provides a sulfur concrete steel reinforcement bonding and corrosion protection structure, which ultimately forms a tightly bonded structure of "steel reinforcement - composite anti-corrosion bonding coating - solid waste aggregate based sulfur concrete - surface hydrophobic anti-icing coating", achieving multiple synergistic effects of chemical bonding + mechanical interlocking + dual corrosion protection + solid waste utilization + surface protection.

[0033] Example 2 A method for preparing a sulfur concrete reinforced concrete anti-corrosion structure, used to prepare the sulfur concrete reinforced concrete anti-corrosion structure described in Example 1, includes the following steps: S1: Use an angle grinder and wire brush to remove rust and oil from the steel bar body 1. After removing rust, oil, and oxide scale, use a high-pressure air of 0.6MPa to blow away the surface slag and dust, and control the surface roughness Ra of the steel bar body 1 to be 12.5~25μm, which lays the foundation for subsequent coating adhesion and mechanical bonding. S2: Sacrificial anode anti-corrosion layer 2 and bonding layer 3 are sequentially coated on the surface of the pretreated steel bar body 1. After the surface of sacrificial anode anti-corrosion layer 2 is dried, bonding layer 3 is coated. The total thickness of sacrificial anode anti-corrosion layer 2 and bonding layer 3 is controlled at 80-150μm. Sacrificial anode anti-corrosion layer 2 and bonding layer 3 are seamlessly bonded without gaps, achieving the triple function of physical shielding + electrochemical protection + strong adhesion. Zinc powder is evenly dispersed to achieve physical + electrochemical dual anti-corrosion. S3: Mix the activated aggregate from solid waste with fly ash for 2-3 minutes until uniform, then add molten (130-140℃) industrial sulfur and bio-based composite modifier, continue mixing for 3-5 minutes, and control the mixing discharge temperature at 100-110℃ to obtain modified sulfur concrete. S4: A portable hot air electric heating preheating device (hot air blower) is used to preheat the steel body 1 coated with sacrificial anode anti-corrosion layer 2 and bonding layer 3 to 40-60°C. Modified sulfur concrete is poured simultaneously and vibrated at low frequency to ensure that the solid waste aggregate and sulfur system are tightly bonded without gaps, forming modified sulfur concrete layer 4. S5: After natural cooling to room temperature, avoid disturbance to personnel and loads during the cooling process to ensure the overall integrity of the structure; S6: Apply a hydrophobic / anti-icing coating 5 to the modified sulfur concrete layer 4 using roller coating or spraying. The surface drying time is ≤1 hour, and the complete drying time is ≤4 hours. This achieves surface weather resistance and anti-icing protection.

[0034] Specifically, it also includes step S7: when the modified sulfur concrete layer 4 needs to be repaired, if the repair depth is >50mm, it is poured in layers with each layer having a thickness of ≤30mm. Before pouring the upper layer, the surface of the lower layer is roughened and preheated to 40-50℃, and a 10-20μm thick sulfur modified epoxy adhesive is applied.

[0035] In the repair of sulfur concrete by layered pouring, existing processes do not specifically treat the interlayer bonding surfaces, which easily leads to debonding between layers and reduces overall adhesion performance. This embodiment addresses the thick-layer repair scenario by treating the interlayer bonding surfaces according to the requirements of layered pouring to ensure interlayer bond strength.

[0036] Preferably, in step S4, a low-frequency light vibration is performed during the pouring process at a frequency of 20-30 Hz.

[0037] The sulfur concrete steel reinforcement bonding and anti-corrosion structure and preparation method provided in this application achieve interface densification through the chemical bonding effect of the sacrificial anode anti-corrosion layer 2 and the bonding layer 3, the mechanical interlocking effect of the rough surface of the steel reinforcement body 1, and the preheating and synergistic casting, resulting in an interface bonding strength ≥3.0MPa, which is more than 60% higher than the traditional process, effectively solving problems such as debonding and hollowing. The sacrificial anode anti-corrosion layer 2 achieves dual protection functions of physical shielding and electrochemical protection. Even if the coating is partially damaged, the steel bar body 1 can still be protected through the sacrificial anode effect, fundamentally preventing the electrochemical corrosion of the steel bar body 1 with sulfur. The anti-corrosion life is more than twice that of traditional processes, and it can be adapted to harsh environments such as chemical industry and high salt spray. Modified sulfur concrete layer 4 uses industrial or construction solid waste materials to replace natural aggregates, achieving high-value utilization and full-component utilization of solid waste, and solving the problems of solid waste dumping occupying land and polluting the environment. The coating and preheating pouring processes are simple to operate and do not require complicated equipment. The preparation of modified sulfur concrete is similar to that of traditional processes, and the construction time is comparable. It can bear the service load in 8 hours and can meet the requirements of fast setting and early strength projects. It is suitable for various engineering scenarios such as roads, bridges, hydraulic structures, and chemical industrial park floors.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions 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 invention.

Claims

1. A sulfur-reinforced concrete bonded anti-corrosion structure, characterized in that, include: The sacrificial anode anti-corrosion layer (2), bonding layer (3), modified sulfur concrete layer (4) and surface hydrophobic / anti-icing coating (5) are sequentially set on the steel body (1). The modified sulfur concrete layer (4) is composed of industrial sulfur, bio-based composite modifier, solid waste activated aggregate and fly ash.

2. The sulfur concrete reinforced concrete anti-corrosion structure according to claim 1, characterized in that, The sacrificial anode anti-corrosion layer (2) is composed of zinc powder, rust inhibitor, silane coupling agent and substrate, wherein the substrate is cement slurry or epoxy resin; The mass of the silane coupling agent accounts for 3% to 5% of the mass of the substrate, the mass of the rust inhibitor accounts for 4% of the mass of the substrate, and the mass of the zinc powder accounts for 8% to 12% of the total mass of the sacrificial anode anti-corrosion layer (2).

3. The sulfur concrete reinforced concrete anti-corrosion structure according to claim 2, characterized in that, The zinc powder has a particle size of 80-120 mesh.

4. The sulfur concrete reinforced concrete anti-corrosion structure according to claim 2, characterized in that, The thickness of the sacrificial anode anti-corrosion layer (2) is 30-50 μm.

5. The sulfur concrete reinforced concrete anti-corrosion structure according to claim 1, characterized in that, The adhesive layer (3) is composed of epoxy resin, curing agent and sulfur powder in a mass ratio of 100:30-40:10-15, and the thickness of the adhesive layer (3) is 50-100 μm.

6. The sulfur concrete reinforced concrete anti-corrosion structure according to claim 1, characterized in that, The modified sulfur concrete layer is composed of industrial sulfur, bio-based composite modifier, solid waste activated aggregate and Class I fly ash in a mass ratio of 20-25:1-1.5:65-70:5-8. The activated solid waste aggregate is composed of steel slag, waste ceramic fragments and recycled concrete fragments in a mass ratio of 4:3:

3. The moisture content of the activated solid waste aggregate is <0.5%, and the particle sizes of the steel slag, waste ceramic fragments and recycled concrete are 5-20 mm, 2-5 mm and 0.5-2 mm, respectively.

7. The sulfur concrete reinforced concrete anti-corrosion structure according to claim 6, characterized in that, The bio-based composite modifier is composed of a ternary compound of polyolefin modifier, bio-based polymer and nano-silica; The mass ratio of the polyolefin modifier, the bio-based polymer, and the nano-silica is 4-6:2-4:1-2; The bio-based polymer is one or a combination of two of the following: lignin sulfonate modified product and rosin resin.

8. The sulfur concrete reinforced concrete anti-corrosion structure according to claim 1, characterized in that, The thickness of the surface hydrophobic / anti-icing coating (5) is 30-50 μm, and it is made of resin and nano silica. The mass of nano silica accounts for 5%-8% of the total mass of the surface hydrophobic / anti-icing coating (5). The resin is a fluorinated resin or an organosilicon resin.

9. A method for preparing a sulfur concrete reinforced concrete bonded corrosion-resistant structure, used to prepare the sulfur concrete reinforced concrete bonded corrosion-resistant structure according to any one of claims 1-8, characterized in that, Includes the following steps: S1: Remove rust and oil from the steel bar body (1), blow away surface slag and dust, and control the surface roughness Ra to 12.5~25μm; S2: Apply a sacrificial anode anti-corrosion layer (2) and an adhesive layer (3) sequentially to the steel reinforcement body (1), with the total coating thickness controlled between 80 and 150 μm; S3: After mixing solid waste activated aggregate with fly ash, molten industrial sulfur and bio-based composite modifier are added and stirred to obtain modified sulfur concrete. S4: The steel body (1) coated with sacrificial anode anti-corrosion layer (2) and bonding layer (3) is preheated to 40-60°C, and modified sulfur concrete is poured and vibrated at low frequency to form modified sulfur concrete layer (4). S5: The modified sulfur concrete layer (4) was allowed to cool naturally to room temperature; S6: Apply a hydrophobic / anti-icing coating (5) to the modified sulfur concrete layer (4) by roller coating or spraying.

10. The preparation method according to claim 9, characterized in that, It also includes step S7: when the modified sulfur concrete layer (4) needs to be repaired, when the repair depth is >50mm, it is poured in layers with each layer having a thickness of ≤30mm. Before pouring the upper layer, the surface of the lower layer is roughened and preheated to 40-50℃, and a 10-20μm thick sulfur modified epoxy adhesive is applied.

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