High-weather-resistance high-durability disassembly-free panel with surface protection structure and preparation method

Abstract

The application provides a high-weather-resistance high-durability disassembly-free panel with a surface protection structure and a preparation method, and belongs to the field of building materials. The high-weather-resistance high-durability disassembly-free panel with the surface protection structure comprises a UHPC panel, and a protection structure layer composed of a composite pore sealing agent is arranged on the surface of the UHPC panel; the composite pore sealing agent comprises, in terms of mass fraction, 15-35 parts of nano silicon dioxide, 20-40 parts of lithium silicate, 20-40 parts of calcium sulfoaluminate, 10-25 parts of magnesium oxide and 0.5-5 parts of a high-molecular dispersant. The chloride ion diffusion coefficient of the high-weather-resistance high-durability disassembly-free panel with the surface protection structure is less than 0.02*10 ‑12 m 2 / s, and meanwhile, the panel has excellent weather resistance and durability.

Description

Technical Field

[0001] The present invention belongs to the field of building materials, and in particular to a highly weather-resistant and durable disassembly-free panel with a surface protection structure and a preparation method thereof. Background Art

[0002] In construction, the use of non-disassembly formwork through assembly can significantly improve efficiency, shorten construction periods, and reduce labor intensity. However, traditional formwork materials often struggle to meet the stringent requirements for weather resistance and durability in complex environments. This is particularly true in coastal areas, where buildings are exposed to chloride-containing environments for extended periods. Traditional materials offer limited protection, leading to problems such as steel corrosion and concrete cracking, seriously impacting the building's service life and structural safety.

[0003] Ultra-high performance concrete (UHPC), as a new type of cement-based material, has received widespread attention and application in the construction field in recent years due to its ultra-high toughness, strength and durability, as well as excellent impermeability.

[0004] For example, Chinese invention patent application number 201911317857.5 discloses a hybrid fiber ultra-high performance concrete (UHPC) pole and its manufacturing method. The ultra-high performance concrete used in this pole is composed of a specific combination of cement, silica fume, quartz sand of varying grades, crushed stone, a high-efficiency water reducer, water, polypropylene fiber, and basalt fiber. This technology demonstrates the potential for UHPC applications in specific components, but its formulation and performance characteristics are not fully suitable for applications such as formwork removal.

[0005] For example, the working invention patent application with application number 202411590256.2 discloses a UHPC material with a high bulk density and high elastic modulus, and its preparation method. The UHPC material includes cement, fly ash microspheres, silica fume, bauxite, corundum particles, alumina, steel fiber, polycarboxylate superplasticizer, and water. While this material has a high bulk density and elastic modulus, it still has deficiencies in fluidity, formability, and resistance to chloride ion penetration, limiting its application in complex construction environments such as those requiring formwork removal.

[0006] Although UHPC has many advantages, traditional UHPC materials still face some challenges in practical applications, such as insufficient fluidity, poor formability, and poor resistance to chloride ion permeability. These problems have, to a certain extent, limited its application in non-disassembly formwork. Summary of the Invention

[0007] The present invention aims to provide a highly weather-resistant and durable non-disassembly panel with a surface protection structure and a preparation method, which solves the problems of poor chloride ion permeability, poor weather resistance and poor durability of UHPC materials. At the same time, the UHPC panel material provided by the present invention has good fluidity and is easy to process and shape.

[0008] The highly weather-resistant and durable non-disassembly panel with a surface protection structure comprises a UHPC panel, and a protective structure layer composed of a composite sealing agent is provided on the surface of the UHPC panel;

[0009] The composite sealing agent comprises, by weight, 15 to 35 parts of nano-silicon dioxide, 20 to 40 parts of lithium silicate, 20 to 40 parts of calcium sulfoaluminate, 10 to 25 parts of magnesium oxide and 0.5 to 5 parts of a polymer dispersant.

[0010] In the composite sealer, the various components exhibit significant synergistic effects. Nano-silica, with its small particle size advantage, fills pores, providing a foundation for the attachment and growth of lithium silicate hydrolysis products. The silanol groups on its surface can undergo a polycondensation reaction with the silicic acid produced by lithium silicate hydrolysis, forming more silicon-oxygen bonds and strengthening the gel network structure. At the same time, nano-silica fills the pores, providing more attachment sites for the hydration products of calcium sulfoaluminate and magnesium oxide, allowing hydration products such as ettringite to deposit more evenly in the pores and improving the filling density. The expansion pressure generated by the hydration of calcium sulfoaluminate promotes the nano-silica to better fill the fine details of the pores. The two work together to effectively fill pores of different sizes and improve the integrity of the seal. Furthermore, the alkaline environment created by the hydration of magnesium oxide is beneficial to the activity of the silanol groups on the surface of the nano-silica, promoting their chemical reactions with other components and further enhancing the sealing effect. Lithium silicate hydrolyzes to form a film, creating an alkaline environment that is beneficial to the hydration reaction of calcium sulfoaluminate, accelerating the formation of hydration products such as ettringite and improving filling efficiency. The hydration products of calcium sulfoaluminate and the hydrolysis and condensation products of lithium silicate are intertwined, and the alkaline environment regulated by magnesium oxide promotes the reaction. The gel can also wrap magnesium oxide and its hydration products, forming a more complex and stable network structure, enhancing the overall strength and sealing properties of the sealer. Calcium sulfoaluminate and magnesium oxide both expand upon hydration and jointly fill the pores. The alkaline environment regulated by magnesium oxide is beneficial to the reaction of calcium sulfoaluminate, and the interpenetration of the two products enhances stability. Polymer dispersants prevent particle agglomeration, improve the dispersion and compatibility of the various components, ensure uniform distribution and sufficient reaction of the various components, and tightly combine nano-silica, lithium silicate, calcium sulfoaluminate, magnesium oxide, etc., comprehensively improving the uniformity, stability, and sealing performance of the sealer.

[0011] Preferably, the UHPC panel comprises the following components, calculated by weight: 500-1000 parts of Portland cement, 8-12 parts of high alumina cement, 300-400 parts of spherical fly ash, 120-180 parts of silica fume, 900-1000 parts of 0.075-3 mm graded quartz sand, 45-80 parts of water reducer, 18-25 parts of expansion agent, 8-12 parts of metakaolin powder, 35-80 parts of steel fiber, 20-30 parts of polymer fiber and 5-15 parts of composite sealing agent.

[0012] Preferably, the polymer dispersant includes a polyacrylate dispersant or a polyether dispersant.

[0013] Preferably, the mass ratio of the 0.075-3 mm graded quartz sand, specifically 0.075-0.2 mm quartz sand, 0.2-0.35 mm quartz sand, 0.35-1.5 mm quartz sand, and 1.5-3 mm quartz sand is 2-4:3-5:6-8:5-7.

[0014] Preferably, the particle size of the spherical fly ash is 12-38 μm, and the sphericity is not less than 0.9.

[0015] Preferably, the particle size of the metakaolin powder is no greater than 25 μm; the particle size of the silica fume is no greater than 25 μm; and the particle size of the metakaolin powder is no greater than 50 μm.

[0016] Preferably, the expansion agent comprises magnesium oxide and modified phosphogypsum in a mass ratio of 0.8 to 1.2:1; the modified phosphogypsum is α-gypsum and / or β-gypsum obtained by calcining phosphogypsum. The expansion agent is a combination of magnesium oxide and modified phosphogypsum, with the magnesium oxide used for initial expansion and the modified phosphogypsum used for later expansion.

[0017] Preferably, when the modified phosphogypsum is a complex of α-gypsum and β-gypsum obtained by calcining phosphogypsum, the mass ratio of α-gypsum to β-gypsum is 7:3 to 9:1.

[0018] The present application takes Portland cement and high-alumina cement as cementitious materials, wherein the Portland cement provides early strength, and the high-alumina cement can accelerate the hardening speed; in the hydration process, the two complement each other, and jointly promote the rapid growth and long-term stability of the strength of the UHPC panel. The spherical fly ash can improve the flow performance of the mixture. The high activity of silica fume can fill the pores of the cement stone, improve the compactness, and enhance the interfacial bonding force, thereby further improving the strength and durability. The 0.075-3 mm graded quartz sand prepared according to the performance requirements of the present application can form a close-packed structure, reduce the porosity, and improve the compactness, strength and impermeability of the UHPC panel. The steel fibers have high strength and elastic modulus, can effectively bear the load, and improve the tensile and bending strength of the panel; the polymer fibers can inhibit the generation of early shrinkage cracks, and enhance the toughness and impact resistance; the two complement each other, and significantly improve the mechanical properties and crack resistance of the UHPC panel. The metakaolin powder, as a mineral admixture, improves the plasticity of the mixture and the strength after hardening, and improves the durability and chemical resistance. The expansive agent provided by the present application is composed of magnesium oxide and modified gypsum in a certain proportion, can compensate for the shrinkage of concrete, prevent cracking, and improve the volume stability. The composite pore sealing agent provided by the present application performs pore sealing treatment on the UHPC panel, forms a protective structure on the surface of the UHPC panel, effectively improves the chloride ion penetration resistance and water resistance of the UHPC panel, and further improves the weather resistance and durability of the UHPC panel; at the same time, since the composite pore sealing agent is composed of inorganic materials, it can better resist ultraviolet radiation, and further improve the weather resistance and durability.

[0019] The high-weatherability high-durability non-demolition panel with a surface protective structure is mainly prepared by the following steps:

[0020] S1, Portland cement, high-alumina cement, spherical fly ash, silica fume, metakaolin, and quartz sand are added into a mixer according to the proportions, and dry mixing is performed to fully mix and uniformly disperse the materials;

[0021] S2, a water reducing agent and an expansive agent are added, and dry mixing is continued to uniformly disperse the additives in the materials;

[0022] S3, steel fibers and polymer fibers are added, and stirring is performed to uniformly disperse the fibers in the materials;

[0023] S4, water is added according to the water-binder ratio requirement, and stirring is performed until a uniform UHPC mixture with good fluidity is formed;

[0024] S5, the UHPC mixture is poured into a mold for molding and curing, and a UHPC panel is obtained;

[0025] S6. Dispersing the composite sealing agent in water to prepare a suspension, spraying the suspension on the surface of the UHPC panel, and preparing the highly weather-resistant and highly durable non-disassembly panel with a surface protection structure after curing.

[0026] Preferably, in step S6, a wet roller is used to roll the surface within 12 hours after spraying to remove floating dust and promote further hydration and crystallization, which can greatly increase adhesion.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The highly weather-resistant and durable non-disassembly panel with a surface protection structure provided by the present invention has a protection structure composed of a composite sealing agent on the surface. The main purpose of the protection structure is to prevent water penetration and significantly improve the ability to resist chloride ion corrosion. At the same time, the protection structure has super strong adhesion to the UHPC panel. After scraping with a metal shovel, only scratches are left, and the protection structure still does not fall off. Therefore, the highly weather-resistant and durable non-disassembly panel with a surface protection structure provided by the present invention has excellent weather resistance and durability. From the analysis of the chloride ion penetration resistance, due to the extremely low porosity and non-connected pore structure of the UHPC material, the chloride ion diffusion coefficient is less than 0.02×10 -12 m 2 / s.

[0029] 2. The highly weather-resistant and durable non-disassembly panel with a surface protection structure provided by the present invention introduces a composite sealing agent and optimizes the pore structure. The sealing agent is made of inorganic material, which can maintain stable performance for a long time under various harsh environmental conditions and effectively resist the influence of factors such as ultraviolet rays, high temperature, low temperature, and humidity changes.

[0030] 3. The ultra-low porosity and disconnected pore structure of the highly weather-resistant, durable, and non-disassembly-removed panels with surface protection provided by this invention provide excellent impermeability and resistance to chloride ion penetration, thereby ensuring exceptional durability. The projected service life is easily over 100 years, significantly exceeding the lifespan of traditional building materials.

[0031] 4. The highly weather-resistant and durable non-disassembly panel with a surface protection structure provided by the present invention ensures the good fluidity and formability of the UHPC mixture in the non-disassembly formwork application by precisely controlling the particle size and ratio of the raw materials and a reasonable mixing process, thereby improving construction efficiency and quality.

[0032] 5. Due to its excellent performance, the highly weather-resistant and durable non-disassembly panel with a surface protection structure provided by the present invention is suitable for construction in various complex environments, such as coastal buildings, bridges, tunnels, marine engineering, etc., and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0034] Figure 1 This is a surface morphology diagram of the highly weather-resistant and durable disassembly-free panel with a surface protection structure of the present invention before spraying the composite sealing agent.

[0035] Figure 2 This is a surface morphology diagram of the highly weather-resistant and durable disassembly-free panel with a surface protection structure of the present invention after spraying a composite sealing agent.

[0036] Figure 3 This is a surface structure diagram of the highly weather-resistant and durable non-disassembly panel with a surface protection structure of the present invention after being magnified under a 40x microscope.

[0037] Figure 4 This is a surface structure diagram of the high-weather-resistant and high-durability disassembly-free panel with a surface protection structure of the present invention after being scraped with a metal spatula and magnified under a 40x microscope. DETAILED DESCRIPTION

[0038] The technical scheme of the present invention is further described below through examples. The raw materials used in the examples can be purchased from the market or prepared by conventional methods.

[0039] Example 1

[0040] A highly weather-resistant and durable panel with a surface protection structure, comprising a UHPC panel, wherein a protective structure layer composed of a composite sealing agent is provided on the surface of the UHPC panel;

[0041] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is composed of the following raw materials, calculated by weight: 600 parts of silicate cement, 10 parts of high-alumina cement, 350 parts of spherical fly ash (particle size of 12-38 μm, sphericity of not less than 0.9), 150 parts of silica fume (particle size of not more than 25 μm), 0.075-3 mm graded quartz sand (specific proportions are (specifically 0.075-0.2 mm quartz sand, 0.2-0.35 mm quartz sand, 0.35-1.5 mm quartz sand, 1.5-3 The preparation method comprises the following steps: preparing the composite material of the present invention: preparing a quartz sand having a mass ratio of 3:4:6:5 and a diameter of 0.1 mm (the mass ratio of which is 3:4:6:5), 950 parts of a water reducer, 60 parts of a swelling agent, 20 parts of an expanding agent (composed of magnesium oxide and modified gypsum in a mass ratio of 1:1, and the modified gypsum is a composite of α-gypsum and β-gypsum obtained by calcining phosphogypsum, in a mass ratio of 8:2), 10 parts of metakaolin powder (particle size not greater than 25 μm), 50 parts of steel fiber, 25 parts of polymer fiber, and 10 parts of a composite sealing agent (composed of nano-silica, lithium silicate, calcium sulfoaluminate, magnesium oxide, and a polyacrylate dispersant SNF FLOSPERSE 3000 (purchased from Foshan Yaotian Technology Co., Ltd.) in a mass ratio of 20:30:30:20:3).

[0042] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is mainly prepared by the following steps:

[0043] S1. Add Portland cement, high alumina cement, spherical fly ash, silica fume, metakaolin, and quartz sand into a mixer according to the proportions, and dry mix until the materials are fully mixed;

[0044] S2. Add water reducer and expansion agent, and continue dry mixing to make the additives evenly dispersed in the material;

[0045] S3, adding steel fiber and polymer fiber, stirring to evenly disperse the fibers in the material;

[0046] S4. Add water according to the water-binder ratio of 0.18 and stir until a uniform UHPC mixture with good fluidity is formed;

[0047] S5, pouring the UHPC mixture into a mold for molding and curing to obtain a UHPC board;

[0048] S6. Disperse the composite sealing agent in water to prepare a suspension, spray the suspension on the surface of the UHPC board, roll the surface with a wet roller within 12 hours after spraying, and after curing, obtain the highly weather-resistant and durable non-disassembly panel with a surface protection structure.

[0049] Example 2

[0050] A highly weather-resistant and durable panel with a surface protection structure, comprising a UHPC panel, wherein a protective structure layer composed of a composite sealing agent is provided on the surface of the UHPC panel;

[0051] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is composed of the following raw materials, calculated by weight: 800 parts of silicate cement, 12 parts of high-alumina cement, 400 parts of spherical fly ash (particle size of 12-38 μm, sphericity of not less than 0.9), 180 parts of silica fume (particle size of not more than 25 μm), 0.075-3 mm graded quartz sand (specific proportions are (specifically 0.075-0.2 mm quartz sand, 0.2-0.35 mm quartz sand, 0.35-1.5 mm quartz sand, 1.5-3 The preparation method comprises the following steps: 1000 parts of quartz sand (the mass ratio of 4:5:7:6 for 0.5 mm) of quartz sand (the mass ratio of 4:5:7:6 for 0.5 mm) of water reducer, 80 parts of expansive agent, 25 parts of expansion agent (composed of magnesium oxide and modified gypsum in a mass ratio of 0.9:1, and the modified gypsum is a composite of α-gypsum and β-gypsum after calcining phosphogypsum, with a mass ratio of 9:1), 12 parts of metakaolin powder (particle size not greater than 25 μm), 80 parts of steel fiber, 30 parts of polymer fiber and 15 parts of composite sealing agent (composed of nano-silica, lithium silicate, calcium sulfoaluminate, magnesium oxide and polyacrylate dispersant SNF FLOSPERSE 3000 in a mass ratio of 15:20:40:15:5).

[0052] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is mainly prepared by the following steps:

[0053] S1. Add Portland cement, high alumina cement, spherical fly ash, silica fume, metakaolin, and quartz sand into a mixer according to the proportions, and dry mix until the materials are fully mixed;

[0054] S2. Add water reducer and expansion agent, and continue dry mixing to make the additives evenly dispersed in the material;

[0055] S3, adding steel fiber and polymer fiber, stirring to evenly disperse the fibers in the material;

[0056] S4. Add water according to the water-binder ratio of 0.24 and stir until a uniform UHPC mixture with good fluidity is formed;

[0057] S5, pouring the UHPC mixture into a mold for molding and curing to obtain a UHPC board;

[0058] S6. Disperse the composite sealing agent in water to prepare a suspension, spray the suspension on the surface of the UHPC board, roll the surface with a wet roller within 12 hours after spraying, and after curing, obtain the highly weather-resistant and durable non-disassembly panel with a surface protection structure.

[0059] Example 3

[0060] A highly weather-resistant and durable panel with a surface protection structure, comprising a UHPC panel, wherein a protective structure layer composed of a composite sealing agent is provided on the surface of the UHPC panel;

[0061] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is composed of the following raw materials, calculated by weight: 500 parts of silicate cement, 8 parts of high-alumina cement, 300 parts of spherical fly ash (particle size of 12-38 μm, sphericity of not less than 0.9), 120 parts of silica fume (particle size of not more than 25 μm), 0.075-3 mm graded quartz sand (specific proportions are (specifically 0.075-0.2 mm quartz sand, 0.2-0.35 mm quartz sand, 0.35-1.5 mm quartz sand, 1.5-3 The preparation method comprises the following steps: preparing the preparation method of the present invention: preparing the first-class composite material of the present invention; ...

[0062] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is mainly prepared by the following steps:

[0063] S1. Add Portland cement, high alumina cement, spherical fly ash, silica fume, metakaolin, and quartz sand into a mixer according to the proportions, and dry mix until the materials are fully mixed;

[0064] S2. Add water reducer and expansion agent, and continue dry mixing to make the additives evenly dispersed in the material;

[0065] S3, adding steel fiber and polymer fiber, stirring to evenly disperse the fibers in the material;

[0066] S4. Add water according to the water-binder ratio of 0.18 and stir until a uniform UHPC mixture with good fluidity is formed;

[0067] S5, pouring the UHPC mixture into a mold for molding and curing to obtain a UHPC board;

[0068] S6. Disperse the composite sealing agent in water to prepare a suspension, spray the suspension on the surface of the UHPC board, roll the surface with a wet roller within 12 hours after spraying, and after curing, obtain the highly weather-resistant and durable non-disassembly panel with a surface protection structure.

[0069] Example 4

[0070] A highly weather-resistant and durable panel with a surface protection structure, comprising a UHPC panel, wherein a protective structure layer composed of a composite sealing agent is provided on the surface of the UHPC panel;

[0071] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is composed of the following raw materials, calculated by weight: 1000 parts of silicate cement, 12 parts of high-alumina cement, 400 parts of spherical fly ash (particle size of 12-38 μm, sphericity of not less than 0.9), 180 parts of silica fume (particle size of not more than 25 μm), 0.075-3 mm graded quartz sand (specific proportions are (specifically 0.075-0.2 mm quartz sand, 0.2-0.35 mm quartz sand, 0.35-1.5 mm quartz sand, 1.5-3 The preparation method comprises the following steps: 1000 parts of quartz sand (with a mass ratio of 4:5:7:6 for 0.1 mm), 80 parts of water reducer, 25 parts of expansion agent (composed of magnesium oxide and modified gypsum in a mass ratio of 1.2:1, and the modified gypsum is a composite of α-gypsum and β-gypsum after calcining phosphogypsum, with a mass ratio of 9:1), 12 parts of metakaolin powder (particle size not greater than 25 μm), 80 parts of steel fiber, 30 parts of polymer fiber and 15 parts of composite sealing agent (composed of nano-silica, lithium silicate, calcium sulfoaluminate, magnesium oxide and polyacrylate dispersant SNF FLOSPERSE 3000 in a mass ratio of 15:40:40:15:5).

[0072] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is mainly prepared by the following steps:

[0073] S1. Add Portland cement, high alumina cement, spherical fly ash, silica fume, metakaolin, and quartz sand into a mixer according to the proportions, and dry mix until the materials are fully mixed;

[0074] S2. Add water reducer and expansion agent, and continue dry mixing to make the additives evenly dispersed in the material;

[0075] S3, adding steel fiber and polymer fiber, stirring to evenly disperse the fibers in the material;

[0076] S4. Add water according to the water-binder ratio of 0.25 and stir until a uniform UHPC mixture with good fluidity is formed;

[0077] S5, pouring the UHPC mixture into a mold for molding and curing to obtain a UHPC board;

[0078] S6. Disperse the composite sealing agent in water to prepare a suspension, spray the suspension on the surface of the UHPC board, and roll the surface again with a wet roller within 12 hours after spraying. After curing, the highly weather-resistant and durable non-disassembly panel with a surface protection structure is obtained.

[0079] Example 5

[0080] A highly weather-resistant and durable panel with a surface protection structure, comprising a UHPC panel, wherein a protective structure layer composed of a composite sealing agent is provided on the surface of the UHPC panel;

[0081] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is composed of the following raw materials, calculated by weight: 1000 parts of silicate cement, 10 parts of high-alumina cement, 375 parts of spherical fly ash (particle size of 12-38 μm, sphericity of not less than 0.9), 165 parts of silica fume (particle size of not more than 25 μm), 0.075-3 mm graded quartz sand (specific proportions are (specifically 0.075-0.2 mm quartz sand, 0.2-0.35 mm quartz sand, 0.35-1.5 mm quartz sand, 1.5-3 The preparation method comprises the following steps: preparing the composite material of the present invention: 987.5 parts of quartz sand (with a mass ratio of 3.5:4.5:6.5:6) with a diameter of 0.1 mm (mm) and a thickness of 1 mm (mm). The mass ratio of the quartz sand is 3.5:4.5:6.5:6), 72.5 parts of water reducer, 22.5 parts of expansion agent (composed of magnesium oxide and modified gypsum in a mass ratio of 1:1, and the modified gypsum is a composite of α-gypsum and β-gypsum after calcining phosphogypsum, with a mass ratio of 8:2), 11.25 parts of metakaolin powder (particle size not greater than 25 μm), 62.5 parts of steel fiber, 28.75 parts of polymer fiber and 12.25 parts of composite sealing agent (composed of nano-silica, lithium silicate, calcium sulfoaluminate, magnesium oxide and polyether dispersant Lencolo 1002 in a mass ratio of 21.25:33.75:33.75:22.5:4.5).

[0082] The highly weather-resistant and durable non-disassembly panel with a surface protection structure is mainly prepared by the following steps:

[0083] S1. Add Portland cement, high alumina cement, spherical fly ash, silica fume, metakaolin, and quartz sand into a mixer according to the proportions, and dry mix until the materials are fully mixed;

[0084] S2. Add water reducer and expansion agent, and continue dry mixing to make the additives evenly dispersed in the material;

[0085] S3, adding steel fiber and polymer fiber, stirring to evenly disperse the fibers in the material;

[0086] S4. Add water according to the water-binder ratio of 0.22 and stir until a uniform UHPC mixture with good fluidity is formed;

[0087] S5, pouring the UHPC mixture into a mold for molding and curing to obtain a UHPC board;

[0088] S6. Disperse the composite sealing agent in water to prepare a suspension, spray the suspension on the surface of the UHPC board, and roll the surface again with a wet roller within 12 hours after spraying. After curing, the highly weather-resistant and durable non-disassembly panel with a surface protection structure is obtained.

[0089] Experimental testing and data analysis

[0090] 1. Fluidity test

[0091] The fluidity was measured using the static mortar fluidity method. The specific procedure was as follows: The UHPC mixture from step S4 of Examples 1-5 was placed in a cement mortar fluidity truncated cone mold of specified dimensions (height 60±0.5 mm, upper inner diameter 70±0.5 mm, lower inner diameter 100±0.5 mm, lower outer diameter 120 mm, this instrument complies with the requirements of GB / T 2419-2016, Cement Mortar Fluidity Determination Method). After leveling, the mold was lifted and the average of the longitudinal and transverse diameters of the mixture was taken as the fluidity value. The results are shown in Table 1.

[0092] Table 1 Fluidity data of UHPC mixtures in Examples 1 to 5

[0093]

[0094] 2. Compressive strength and flexural strength test

[0095] According to GB17671-1999 “Test method for strength of cement mortar”, the compressive strength and flexural strength were tested. The test block size was 40 mm × 40 mm × 160 mm prism. The results are shown in Table 2.

[0096] Table 2 Compressive strength and flexural strength data of UHPC materials in Examples 1 to 5

[0097]

[0098] 3. Chloride ion permeability test

[0099] Chloride ion permeability was tested using the RCM method (GB / T 50082-2009, Test Methods for Long-term Performance and Durability of Ordinary Concrete). The test period was 84 days. The results are shown in Table 3.

[0100] Table 3 Chloride ion permeability resistance data of high weather resistance and high durability non-disassembly panels with surface protection structure in Examples 1 to 5

[0101]

[0102] 4. Surface morphology analysis

[0103] Depend on Figures 1 and 2 As can be seen, the surface of UHPC panels without a sealer may exhibit significant porosity. This is because UHPC materials contain micropores formed by cement hydration and aggregate accumulation. Exposed pores can reduce the panel's impermeability and durability, allowing moisture and corrosive substances to easily penetrate the material, impacting its performance. However, after applying a sealer, the number of pores on the surface of UHPC panels should be significantly reduced. The nano-silica in the composite sealer fills the pores, while calcium sulfoaluminate and magnesium oxide react to form an expansive product that further seals the pores. This porosity reduction effect can be seen visually in the image, significantly improving the panel's impermeability and durability. Furthermore, the surface flatness and finish of the panel should be improved after applying the sealer. The sealer fills the pores, "repairing" and "leveling" the surface to a certain extent, making it smoother. This not only improves the panel's appearance but also reduces dirt adhesion and enhances its anti-fouling properties.

[0104] have Figures 3 and 4 It can be seen that the material of the present invention forms a crystalline structure on the surface of the panel. After being scraped with a metal spatula, the surface protective structure does not peel off, leaving only some superficial scratches. This is because the composite sealant penetrates the surface layer of the UHPC panel during the sealing process, so the composite sealant has excellent bonding strength with the UHPC panel substrate. At the same time, since the composite sealant uses inorganic materials, it can better resist ultraviolet radiation.

[0105] Panels without sealant have poor surface conditions and may be more susceptible to environmental erosion during actual use, leading to performance degradation. However, panels with sealant, on the other hand, have a superior surface condition that allows them to better withstand adverse external factors, meeting the requirements for highly weather-resistant and durable composite formwork in construction projects.

[0106] Although the present application has been described with reference to specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely illustrative of the present application as defined by the appended claims and are deemed to cover any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, those skilled in the art may make various modifications and variations to the present application without departing from the scope of the present application. Thus, the present application is intended to include such modifications and variations if they fall within the scope of the claims of the present application and their equivalents.

Claims

1. A highly weather-resistant and durable panel with a surface protection structure, characterized by: It includes a UHPC panel, and a protective structural layer composed of a composite sealing agent is provided on the surface of the UHPC panel; The highly weather-resistant and durable non-disassembly panel comprises the following components, calculated by weight: 500-1000 parts of Portland cement, 8-12 parts of high-alumina cement, 300-400 parts of spherical fly ash, 120-180 parts of silica fume, 900-1000 parts of 0.075-3 mm graded quartz sand, 45-80 parts of water reducer, 18-25 parts of expansion agent, 8-12 parts of metakaolin powder, 35-80 parts of steel fiber, 20-30 parts of polymer fiber, and 5-15 parts of composite sealing agent. The composite sealing agent comprises, by weight, 15 to 35 parts of nano-silicon dioxide, 20 to 40 parts of lithium silicate, 20 to 40 parts of calcium sulfoaluminate, 10 to 25 parts of magnesium oxide, and 0.5 to 5 parts of a polymer dispersant; The polymer dispersant includes a polyacrylate dispersant or a polyether dispersant.

2. The highly weather-resistant and durable non-disassembly panel with a surface protection structure according to claim 1, wherein: The mass ratio of the 0.075-3 mm graded quartz sand, specifically 0.075-0.2 mm quartz sand, 0.2-0.35 mm quartz sand, 0.35-1.5 mm quartz sand, and 1.5-3 mm quartz sand, is 2-4:3-5:6-8:5-7.

3. The highly weather-resistant and durable non-disassembly panel with a surface protection structure according to claim 1 is characterized by: The expansion agent is composed of magnesium oxide and modified phosphogypsum in a mass ratio of 0.8-1.2:1; the modified phosphogypsum is α-gypsum and / or β-gypsum obtained by calcining phosphogypsum.

4. The highly weather-resistant and durable non-disassembly panel with a surface protection structure according to claim 3 is characterized by: The modified phosphogypsum is a complex of α-gypsum and β-gypsum obtained by calcining phosphogypsum, and the mass ratio of α-gypsum to β-gypsum is 7:3-9:

1.

5. The highly weather-resistant and durable non-disassembly panel with a surface protection structure according to claim 1, wherein: The particle size of the spherical fly ash is 12-38 μm, and the sphericity is not less than 0.

9.

6. The highly weather-resistant and durable non-disassembly panel with a surface protection structure according to claim 1, wherein: The particle size of the metakaolin powder is no greater than 25 μm; the particle size of the silica fume is no greater than 25 μm.

7. A method for preparing a highly weather-resistant and durable non-disassembly panel with a surface protection structure according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Add Portland cement, high alumina cement, spherical fly ash, silica fume, metakaolin powder, and quartz sand into a mixer according to the proportions, and dry mix until the materials are fully mixed; S2. Add water reducer and expansion agent, and continue dry mixing to make the additives evenly dispersed in the material; S3, adding steel fiber and polymer fiber, stirring to evenly disperse the fibers in the material; S4. Add water according to the water-binder ratio requirements and stir until a uniform UHPC mixture with good fluidity is formed; S5, pouring the UHPC mixture into a mold for molding and curing to obtain a UHPC board; S6. Dispersing the composite sealing agent in water to prepare a suspension, spraying the suspension on the surface of the UHPC board, and preparing the highly weather-resistant and highly durable non-disassembly panel with a surface protection structure after curing.

8. The method for preparing a highly weather-resistant and durable non-disassembly panel with a surface protection structure according to claim 7, wherein: In step S6, the surface is brushed once with a wet roller within 12 hours after spraying.

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