Grouting material for offshore wind power engineering

Abstract

The invention discloses a grouting material for offshore wind power engineering, and belongs to the technical field of building materials. The grouting material for offshore wind power engineering comprises the following raw materials in parts by weight: 10-60 parts of cement, 10-60 parts of a mineral admixture, 5-50 parts of fine aggregate, 0.5-5 parts of a hydrophobic functional material and 0.2-2 parts of an additive. Wherein the hydrophobic functional material is obtained by reacting modified silicon dioxide, perdecafluorooctyltriethoxysilane, hydrogen-containing silicone oil and tetraethyl silicate. The grouting material prepared by the invention has excellent corrosion resistance, impermeability, freeze-thaw resistance, durability and early and later strength, and is suitable for offshore wind power engineering construction.

Description

Grouting materials for offshore wind power projects Technical Field

[0001] This invention belongs to the field of building materials technology, specifically relating to a grouting material for offshore wind power projects. Background Technology

[0002] Grouting materials, as key materials used in engineering construction to fill voids, reinforce structures, and transfer loads, directly affect the stability and durability of the overall project. In traditional civil and architectural engineering, grouting material technology is relatively mature, with formulations and performance indicators largely based on onshore or conventional environments, generally pursuing high fluidity, high early strength, and final compressive strength. However, when applied to harsh marine environments, especially as key structural connection materials in offshore wind power projects, the inherent limitations of these grouting materials become apparent. Offshore wind power, as a highly efficient and land-saving clean energy industry, is becoming an important direction for global energy transition. Its wind turbine foundation structures, such as monopiles, gravity foundations, and jacket structures, require grouting materials for structural fixation and load transfer. The marine environment, characterized by salt spray, high humidity, and high-pressure water erosion, places higher demands on the corrosion resistance, density, and impermeability of grouting materials. The hydrophobicity of grouting materials directly affects their service life and structural safety. However, most mainstream grouting materials on the market are designed for onshore engineering construction and lack special properties for the complex marine environment. They have problems such as high water absorption and large porosity, resulting in poor early and long-term corrosion resistance, easy occurrence of alkali-aggregate reaction, salt corrosion and freeze-thaw damage, and reduced overall performance of the grouting layer.

[0003] Currently, research on grouting materials for offshore wind power is relatively limited, and some unresolved issues remain. For example, Chinese patent CN202310934823.0 discloses a grouting material for offshore wind power jacket structures and its application method. This material uses dense corundum micro-powder as ultrafine aggregate, adjusts the composition of mineral admixtures to compound cement and sand to achieve good early and late strength, and adds hydroxymethylated polyacrylamide, wetting and viscosity-reducing agents, and other additives to ensure the grouting material's workability, thereby improving its elastic modulus and early strength. However, this grouting material does not solve the problem of poor durability and cannot meet the high durability requirements for grouting materials used in offshore wind power. Chinese patent CN202310133207.5 discloses a cement-based grouting material for wind turbine foundation tower base installation and its preparation method, comprising cement, mineral admixtures, aggregates, composite functional materials, fiber combinations, water, and other components. It uses aggregates of various particle sizes and densities in combination, and incorporates a specially formulated fiber combination, improving the grouting material's elastic modulus, flexural strength, compressive strength, crack resistance, and toughness. However, this grouting material uses steel fiber combined with polyvinyl alcohol fiber for toughening, which can lead to corrosion problems such as chloride ion attack in marine application environments, failing to meet the long-term corrosion resistance requirements of grouting materials for offshore wind power. Therefore, there is an urgent need for a new grouting material specifically designed for offshore wind power projects, capable of addressing the technical challenges of offshore wind power construction and ensuring the safe, stable, and long-term operation of the wind turbine structure throughout its entire life cycle. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a special grouting material suitable for offshore wind power projects, which has excellent hydrophobic and impermeable properties and durability, and enhances the structural corrosion resistance and freeze-thaw resistance of the grouting material, thus extending its service life.

[0005] The technical solution adopted in this invention is:

[0006] This invention provides a grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0007] 10-60 parts cement, 10-60 parts mineral admixtures, 5-50 parts fine aggregate, 0.5-5 parts hydrophobic functional materials, and 0.2-2 parts additives.

[0008] Preferably, a grouting material for offshore wind power projects comprises the following raw materials by weight:

[0009] 25-40 parts cement, 25-40 parts mineral admixtures, 18-35 parts fine aggregates, 1.5-3 parts hydrophobic functional materials, and 0.5-1 parts additives.

[0010] Preferably, the method for preparing the hydrophobic functional material is as follows:

[0011] Nano-silica was added to an ethanol aqueous solution and ultrasonically treated. Under stirring, n-octadecyltriethoxysilane and n-octyltrimethoxysilane were added dropwise. After the addition was complete, the temperature was raised, and then triethylamine was added and the reaction was stirred. The mixture was filtered, washed, and dried to obtain modified silica.

[0012] Modified silica was added to toluene and ultrasonically treated. Under nitrogen protection, tridecafluorooctyltriethoxysilane, hydrogen-containing silicone oil, and tetraethyl silicate were added. The pH was adjusted to acidic, and the mixture was heated and stirred to react. The mixture was then filtered, washed, dried, pulverized, and sieved to obtain a hydrophobic functional material.

[0013] Preferably, the weight ratio of the nano-silica, n-octadecyltriethoxysilane, n-octyltrimethoxysilane, and triethylamine is 2-5:0.5-1:0.1-0.5:0.1-0.3.

[0014] Preferably, the weight ratio of the modified silica, tridecafluorooctyltriethoxysilane, hydrogen-containing silicone oil and 0.7-1.2 parts of tetraethyl silicate is 2-5:1-1.5:0.1-0.5:0.7-1.2.

[0015] The hydrophobic functional material prepared in this invention first forms a robust and effective hydrophobic core on the surface of a nano-silica carrier through a composite silanization reaction. The long-chain n-octadecyltriethoxysilane provides significant hydrophobicity and low surface energy, while the short-chain n-octyltrimethoxysilane, with its smaller molecular size and superior permeability, can deeply modify the micropores within the nano-silica carrier. The synergistic effect of both contributes to the formation of a dense and complete hydrophobic layer. This initial hydrophobic treatment alters the capillary wall properties of the nano-substrate, making it hydrophobic, thereby significantly reducing the resistance to moisture and other corrosive media. The original driving force for penetration is capillary adsorption. On this basis, the introduction of fluorinated silanes further endows the shell with excellent low surface energy and chemical inertness, giving it superhydrophobic properties and strong corrosion resistance. At the same time, tetraethyl silicate, as a crosslinking agent, can form a strong siloxane network skeleton, while the addition of hydrogen-containing silicone oil is like embedding a highly active crosslinking enhancer in the skeleton. Through its multiple Si-H bonds, it greatly improves the three-dimensional crosslinking density and mechanical properties of the shell. This dense shell not only physically blocks the diffusion path of the medium, but its chemical stability also ensures that the protective performance does not decrease under long-term harsh environments.

[0016] The addition of the aforementioned hydrophobic functional material in this invention plays a dual role in physical densification and chemical hydrophobicity in grouting materials. Its nanoscale core, acting as micro-aggregate, finely fills the micron-sized pores in the cement matrix, optimizing the pore structure and reducing the number of harmful pores. Its hydrophobicity and dense shell form a highly efficient physicochemical composite barrier, effectively blocking the migration and penetration of water, chloride ions, and sulfate ions. At the same time, by greatly reducing the content of freezeable water and alleviating internal stress during the freeze-thaw process, it simultaneously improves the impermeability, chloride ion penetration resistance, sulfate erosion resistance, and freeze-thaw durability of the grouting material.

[0017] Preferably, the method for preparing the hydrophobic functional material is as follows:

[0018] By weight, 2-5 parts of nano-silica were added to 40-60 parts of an aqueous ethanol solution and ultrasonically treated for 20-50 min. Under stirring at 300-400 r / min, 0.5-1 parts of n-octadecyltriethoxysilane and 0.1-0.5 parts of n-octyltrimethoxysilane were added dropwise. After the addition was complete, the temperature was raised to 70-80℃, and then 0.1-0.3 parts of triethylamine were added and the reaction was stirred for 3-6 h. The mixture was filtered, washed 2-5 times with anhydrous ethanol, and vacuum dried at 50-65℃ for 8-12 h to obtain modified silica.

[0019] Add 2-5 parts of modified silica to 40-60 parts of toluene and sonicate for 10-20 min. Under nitrogen protection, add 1-1.5 parts of tridecafluorooctyltriethoxysilane, 0.1-0.5 parts of hydrogen-containing silicone oil, and 0.7-1.2 parts of tetraethyl silicate. Adjust the pH to 4-5 with hydrochloric acid aqueous solution. Stir and react at 55-65℃ and 200-300 r / min for 3-8 h. Filter, wash 2-5 times with anhydrous ethanol, and vacuum dry and cure at 90-100℃ for 2-5 h. After pulverizing, pass through a 400-600 mesh sieve to obtain the hydrophobic functional material.

[0020] Preferably, the concentration of the ethanol aqueous solution is 85-95 wt%.

[0021] Preferably, the concentration of the hydrochloric acid aqueous solution is 1-2 wt%.

[0022] Preferably, the nano-silica has a particle size of 10-20 nm and a specific surface area of ​​220-280 m². 2 / g.

[0023] Preferably, the viscosity (25°C) of the hydrogen-containing silicone oil is 10-20 mm. 2 / s, with a hydrogen content of 0.35-0.37%.

[0024] Preferably, the frequency of the ultrasound is 40-50kHz and the power is 250-350W.

[0025] Preferably, the dripping time is 10-20 minutes.

[0026] Preferably, the cement is silicate cement.

[0027] Preferably, the silicate cement is at least one of P·Ⅰ52.5, P·Ⅱ52.5, P·Ⅰ52.5R, and P·Ⅱ52.5R.

[0028] Preferably, the mineral admixture is at least one of mineral powder, fly ash, and silica fume.

[0029] Preferably, the mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:1-3.

[0030] Preferably, the fly ash is of grade I.

[0031] Preferably, the mineral powder is of grade S95.

[0032] Preferably, the fine aggregate is at least one of river sand, manufactured sand, and quartz sand.

[0033] Preferably, the fine aggregate is river sand.

[0034] Preferably, the river sand is fine sand with a fineness modulus of 1.6-2.2 and a particle size of 0.25-0.35 mm.

[0035] Preferably, the admixture is at least one of a water-reducing agent, an early-strength agent, and a preservative.

[0036] Preferably, the additive is a water-reducing agent; the water-reducing agent is a polycarboxylate high-performance water-reducing agent.

[0037] Preferably, the polycarboxylate superplasticizer is model PCA®-VIII (Jiangsu Subote New Material Co., Ltd.).

[0038] Preferably, the water-cement ratio of the grouting material used in the offshore wind power project is 0.15-0.22.

[0039] The water-cement ratio refers to the weight ratio of water to cementitious material added to the grouting material used in offshore wind power projects; wherein, cementitious material includes cement and mineral admixtures.

[0040] This invention also discloses a method for preparing the above-mentioned grouting material for offshore wind power projects, which consists of the following steps:

[0041] Cement, mineral admixtures and fine aggregates are mixed to obtain powder; then hydrophobic functional materials and additives are added to the powder and mixed, and water is added at a water-binder ratio of 0.15-0.22 for mixing and stirring to obtain the grouting material for offshore wind power projects.

[0042] The beneficial effects of this invention are:

[0043] The grouting material prepared by this invention, obtained by reacting modified silica, tridecafluorooctyltriethoxysilane, hydrogen-containing silicone oil, and tetraethyl silicate, is a hydrophobic functional material that not only effectively prevents water penetration and has excellent hydrophobic and impermeable properties, significantly reducing seawater salt erosion; but also exhibits strong durability, improved resistance to freeze-thaw cycles, and significantly better corrosion resistance than conventional grouting materials. Furthermore, it boasts high early compressive strength, reaching over 70 MPa in 3 days to meet construction requirements, and over 120 MPa in 28 days, ensuring structural stability and maintaining high strength and density during long-term service. This significantly improves upon the shortcomings of traditional land-based grouting materials in marine environments and is suitable for offshore wind power engineering construction. Detailed Implementation

[0044] The present invention will be further described in detail below with reference to specific embodiments. These embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0045] The following is a description of some of the raw materials used in the examples:

[0046] The cement is P·Ⅱ52.5 silicate cement, manufactured by Anhui Conch Cement Co., Ltd.

[0047] Fly ash, Grade I, 45μm sieve residue: ≤12%, Guangdong Xinze Building Materials Co., Ltd.

[0048] Mineral powder, S95 grade, Henan Haoquan New Materials Co., Ltd.

[0049] River sand, fine sand, fineness modulus: 1.6-2.2, particle size: 0.25-0.35mm, Hunan Tiancheng Sand and Gravel Co., Ltd.

[0050] Polycarboxylate superplasticizer, model: PCA®-VIII, Jiangsu Subote New Material Co., Ltd.

[0051] Nano silica, model: HN-SP15, particle size: 15±5nm, specific surface area: 250±30m² 2 / g, Hangzhou Hengge Nanotechnology Co., Ltd.

[0052] Hydrogen-containing silicone oil, model: RH-H536, viscosity (25℃): 10-20 mm 2 / s, hydrogen content: 0.35-0.37%, Ningbo Runhe High-Tech Materials Technology Co., Ltd.

[0053] Example 1

[0054] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0055] 35 parts cement, 35 parts mineral admixture, 30 parts fine aggregate, 2.5 parts hydrophobic functional material, and 0.8 parts additive.

[0056] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:2; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0057] The preparation method of the hydrophobic functional material is as follows:

[0058] By weight, 4 parts of nano-silica were added to 50 parts of 90wt% ethanol aqueous solution and ultrasonically treated for 30 min at a frequency of 45 kHz and a power of 300 W. Under stirring at 350 r / min, 0.7 parts of n-octadecyltriethoxysilane (CAS: 7399-00-0) and 0.3 parts of n-octyltrimethoxysilane (CAS: 3069-40-7) were added dropwise over a time of 15 min. After the addition was complete, the temperature was raised to 75 °C, and then 0.2 parts of triethylamine were added and the reaction was stirred for another 4 h. The mixture was filtered, washed three times with anhydrous ethanol, and dried under vacuum at 60 °C for 10 h to obtain modified silica.

[0059] Four parts of modified silica were added to 50 parts of toluene and ultrasonically treated for 10 min at a frequency of 45 kHz and a power of 300 W. Under nitrogen protection, 1.2 parts of tridecafluorooctyltriethoxysilane (CAS: 51851-37-7), 0.3 parts of hydrogen-containing silicone oil, and 1 part of tetraethyl silicate were added. The pH was then adjusted to 4.5 with 1 wt% hydrochloric acid aqueous solution. The mixture was stirred at 60 °C and 250 r / min for 6 h. After filtration, the mixture was washed three times with anhydrous ethanol and vacuum dried and cured at 100 °C for 3 h. After pulverization, the mixture was passed through a 500-mesh sieve to obtain the hydrophobic functional material.

[0060] The preparation method of the above-mentioned grouting material for offshore wind power projects consists of the following steps:

[0061] Cement, mineral admixtures and fine aggregates are mixed to obtain powder; then hydrophobic functional materials and additives are added to the powder and mixed, and water is added at a water-binder ratio of 0.18 to mix and stir, thus obtaining the grouting material for offshore wind power projects.

[0062] Example 2

[0063] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0064] 25 parts cement, 25 parts mineral admixture, 18 parts fine aggregate, 1.5 parts hydrophobic functional material, and 0.5 parts additive.

[0065] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:1; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0066] The preparation method of the hydrophobic functional material is the same as that in Example 1.

[0067] The preparation method of the grouting material for the above-mentioned offshore wind power project is the same as that in Example 1.

[0068] Example 3

[0069] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0070] 40 parts cement, 40 parts mineral admixture, 35 parts fine aggregate, 3 parts hydrophobic functional material, and 1 part additive.

[0071] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:3; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0072] The preparation method of the hydrophobic functional material is the same as that in Example 1.

[0073] The preparation method of the grouting material for the above-mentioned offshore wind power project is the same as that in Example 1.

[0074] Example 4

[0075] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0076] 35 parts cement, 35 parts mineral admixture, 30 parts fine aggregate, 2.5 parts hydrophobic functional material, and 0.8 parts additive.

[0077] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:2; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0078] The preparation method of the hydrophobic functional material is as follows:

[0079] By weight, 4 parts of nano-silica were added to 50 parts of 90wt% ethanol aqueous solution and ultrasonically treated for 30 min at a frequency of 45 kHz and a power of 300 W. Under stirring at 350 r / min, 1 part of n-octadecyltriethoxysilane (CAS: 7399-00-0) was added dropwise over a time of 15 min. After the addition was complete, the temperature was raised to 75 °C, and then 0.2 parts of triethylamine were added and the reaction was stirred for another 4 h. The mixture was filtered, washed three times with anhydrous ethanol, and dried under vacuum at 60 °C for 10 h to obtain modified silica.

[0080] Four parts of modified silica were added to 50 parts of toluene and ultrasonically treated for 10 min at a frequency of 45 kHz and a power of 300 W. Under nitrogen protection, 1.2 parts of tridecafluorooctyltriethoxysilane (CAS: 51851-37-7), 0.3 parts of hydrogen-containing silicone oil, and 1 part of tetraethyl silicate were added. The pH was then adjusted to 4.5 with 1 wt% hydrochloric acid aqueous solution. The mixture was stirred at 60 °C and 250 r / min for 6 h. After filtration, the mixture was washed three times with anhydrous ethanol and vacuum dried and cured at 100 °C for 3 h. After pulverization, the mixture was passed through a 500-mesh sieve to obtain the hydrophobic functional material.

[0081] The preparation method of the grouting material for the above-mentioned offshore wind power project is the same as that in Example 1.

[0082] Example 5

[0083] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0084] 35 parts cement, 35 parts mineral admixture, 30 parts fine aggregate, 2.5 parts hydrophobic functional material, and 0.8 parts additive.

[0085] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:2; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0086] The preparation method of the hydrophobic functional material is as follows:

[0087] By weight, 4 parts of nano-silica were added to 50 parts of 90wt% ethanol aqueous solution and ultrasonically treated for 30 min at a frequency of 45 kHz and a power of 300 W. Under stirring at 350 r / min, 1 part of n-octyltrimethoxysilane (CAS: 3069-40-7) was added dropwise over a time of 15 min. After the addition was complete, the temperature was raised to 75 °C, and then 0.2 parts of triethylamine were added and the reaction was stirred for another 4 h. The mixture was filtered, washed three times with anhydrous ethanol, and dried under vacuum at 60 °C for 10 h to obtain modified silica.

[0088] Four parts of modified silica were added to 50 parts of toluene and ultrasonically treated for 10 min at a frequency of 45 kHz and a power of 300 W. Under nitrogen protection, 1.2 parts of tridecafluorooctyltriethoxysilane (CAS: 51851-37-7), 0.3 parts of hydrogen-containing silicone oil, and 1 part of tetraethyl silicate were added. The pH was then adjusted to 4.5 with 1 wt% hydrochloric acid aqueous solution. The mixture was stirred at 60 °C and 250 r / min for 6 h. After filtration, the mixture was washed three times with anhydrous ethanol and vacuum dried and cured at 100 °C for 3 h. After pulverization, the mixture was passed through a 500-mesh sieve to obtain the hydrophobic functional material.

[0089] The preparation method of the grouting material for the above-mentioned offshore wind power project is the same as that in Example 1.

[0090] Example 6

[0091] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0092] 35 parts cement, 35 parts mineral admixture, 30 parts fine aggregate, 2.5 parts hydrophobic functional material, and 0.8 parts additive.

[0093] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:2; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0094] The preparation method of the hydrophobic functional material is as follows:

[0095] By weight, 4 parts of nano-silica were added to 50 parts of toluene and ultrasonically treated for 10 min at a frequency of 45 kHz and a power of 300 W. Under nitrogen protection, 1.2 parts of tridecafluorooctyltriethoxysilane (CAS: 51851-37-7), 0.3 parts of hydrogen-containing silicone oil, and 1 part of tetraethyl silicate were added. The pH was then adjusted to 4.5 with 1 wt% hydrochloric acid aqueous solution. The mixture was stirred at 60 °C and 250 r / min for 6 h. After filtration, the mixture was washed three times with anhydrous ethanol and vacuum dried and cured at 100 °C for 3 h. After pulverization, the mixture was passed through a 500-mesh sieve to obtain the hydrophobic functional material.

[0096] The preparation method of the grouting material for the above-mentioned offshore wind power project is the same as that in Example 1.

[0097] Example 7

[0098] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0099] 35 parts cement, 35 parts mineral admixture, 30 parts fine aggregate, 2.5 parts hydrophobic functional material, and 0.8 parts additive.

[0100] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:2; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0101] The preparation method of the hydrophobic functional material is as follows:

[0102] By weight, 4 parts of nano-silica were added to 50 parts of 90wt% ethanol aqueous solution and ultrasonically treated for 30 min at a frequency of 45 kHz and a power of 300 W. Under stirring at 350 r / min, 0.7 parts of n-octadecyltriethoxysilane (CAS: 7399-00-0) and 0.3 parts of n-octyltrimethoxysilane (CAS: 3069-40-7) were added dropwise over a time of 15 min. After the addition was complete, the temperature was raised to 75 °C, and then 0.2 parts of triethylamine were added and the reaction was stirred for another 4 h. The mixture was filtered, washed three times with anhydrous ethanol, and dried under vacuum at 60 °C for 10 h to obtain modified silica.

[0103] Four parts of modified silica were added to 50 parts of toluene and ultrasonically treated for 10 min at a frequency of 45 kHz and a power of 300 W. Under nitrogen protection, 1.5 parts of tridecafluorooctyltriethoxysilane (CAS: 51851-37-7) and 1 part of tetraethyl silicate were added. The pH was then adjusted to 4.5 with 1 wt% hydrochloric acid aqueous solution. The mixture was stirred at 60 °C and 250 r / min for 6 h. After filtration, the mixture was washed three times with anhydrous ethanol and vacuum dried and cured at 100 °C for 3 h. After pulverization, the mixture was passed through a 500-mesh sieve to obtain the hydrophobic functional material.

[0104] The preparation method of the grouting material for the above-mentioned offshore wind power project is the same as that in Example 1.

[0105] Example 8

[0106] A grouting material for offshore wind power projects, comprising the following raw materials by weight:

[0107] 35 parts cement, 35 parts mineral admixture, 30 parts fine aggregate, 2.5 parts hydrophobic functional material, and 0.8 parts additive.

[0108] The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:2; the fine aggregate is river sand (fine sand); and the admixture is polycarboxylate high-performance water-reducing agent.

[0109] The preparation method of the hydrophobic functional material is as follows:

[0110] By weight, 4 parts of nano-silica were added to 50 parts of 90wt% ethanol aqueous solution and ultrasonically treated for 30 min at a frequency of 45 kHz and a power of 300 W. Under stirring at 350 r / min, 0.7 parts of n-octadecyltriethoxysilane (CAS: 7399-00-0) and 0.3 parts of n-octyltrimethoxysilane (CAS: 3069-40-7) were added dropwise over a time of 15 min. After the addition was complete, the temperature was raised to 75 °C, and then 0.2 parts of triethylamine were added and the reaction was stirred for another 4 h. The mixture was filtered, washed three times with anhydrous ethanol, vacuum dried at 60 °C for 10 h, pulverized, and passed through a 500-mesh sieve to obtain the hydrophobic functional material.

[0111] The preparation method of the grouting material for the above-mentioned offshore wind power project is the same as that in Example 1.

[0112] Test Example 1

[0113] The following performance tests were conducted on the grouting material for offshore wind power projects obtained in the above embodiments. The flowability (truncated cone) and compressive strength were determined according to the method in standard JC / T 986-2018; the loading rate of the press was 2400±200 N / s, and the compressive strength at 3 days and 28 days was measured and recorded. The test results are shown in Table 1.

[0114] Table 1. Flowability and early-to-late-stage strength of grouting materials used in offshore wind power projects

[0115]

[0116] Test Example 2

[0117] The following performance tests were conducted on the grouting materials for offshore wind power projects obtained in the above embodiments. Durability was determined according to the methods in GB / T 50082-2024; specifically, water permeability resistance (permeability grade) was tested using the stepwise pressure method (6.2) in GB / T 50082-2024; chloride ion permeability resistance was tested using the rapid chloride ion migration coefficient method (28-day age) (7.1) in GB / T 50082-2024; sulfate resistance (number of wet and dry cycles) was tested using the sulfate resistance test (28-day age) (14) in GB / T 50082-2024; and freeze-thaw resistance (number of freeze-thaw cycles) was tested using the slow freezing method (28-day age) (4.1) in GB / T 50082-2024. The test results are shown in Table 2.

[0118] Table 2. Durability of Grouting Materials Used in Offshore Wind Power Projects

[0119]

[0120] The test results show that the grouting material for offshore wind power projects in Embodiment 1 of the present invention not only has high early and late strength, but also excellent durability. Its resistance to water penetration, corrosion resistance (resistance to chloride ion penetration and sulfate erosion) and resistance to freeze-thaw cycles are significantly better than those of conventional grouting materials. Compared with Example 1, Examples 4-8, due to the absence of a specific method for preparing hydrophobic functional materials, showed significantly inferior performance in all tests of the corresponding grouting materials for offshore wind power projects compared to Example 1. This is because Example 1 incorporated a specific hydrophobic functional material, which played a dual role in physical densification and chemical hydrophobicity in the grouting material. Its nanoscale core, acting as micro-aggregate, finely filled the micron-sized pores in the cement matrix, optimizing the pore structure and reducing the number of harmful pores. Its hydrophobicity and dense shell constituted a highly efficient physicochemical composite barrier, effectively blocking the migration and penetration of water, chloride ions, and sulfate ions. At the same time, by greatly reducing the content of freezeable water and alleviating internal stress during the freeze-thaw process, it simultaneously improved the impermeability, chloride ion penetration resistance, sulfate erosion resistance, and freeze-thaw durability of the grouting material.

[0121] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A grouting material for offshore wind power projects, characterized in that, By weight, it includes the following raw materials: 10-60 parts cement, 10-60 parts mineral admixtures, 5-50 parts fine aggregates, 0.5-5 parts hydrophobic functional materials, and 0.2-2 parts additives.

2. The grouting material for offshore wind power projects as described in claim 1, characterized in that, By weight, it includes the following raw materials: 25-40 parts cement, 25-40 parts mineral admixtures, 18-35 parts fine aggregates, 1.5-3 parts hydrophobic functional materials, and 0.5-1 parts additives.

3. The grouting material for offshore wind power projects as described in claim 1 or 2, characterized in that, The preparation method of the hydrophobic functional material is as follows: nano-silica is added to an ethanol aqueous solution and ultrasonically treated. Under stirring conditions, n-octadecyltriethoxysilane and n-octyltrimethoxysilane are added dropwise. After the addition is complete, the temperature is raised, and triethylamine is added and the reaction is continued with stirring. The mixture is filtered, washed, and dried to obtain modified silica. The modified silica is added to toluene and ultrasonically treated. Under nitrogen protection, tridecafluorooctyltriethoxysilane, hydrogen-containing silicone oil, and tetraethyl silicate are added. The pH is adjusted to acidic, and the mixture is heated and stirred to react. The mixture is filtered, washed, dried, pulverized, and sieved to obtain the hydrophobic functional material.

4. The grouting material for offshore wind power projects as described in claim 3, characterized in that, The weight ratio of the nano-silica, n-octadecyltriethoxysilane, n-octyltrimethoxysilane, and triethylamine is 2-5:0.5-1:0.1-0.5:0.1-0.3; the weight ratio of the modified silica, tridecafluorooctyltriethoxysilane, hydrogen-containing silicone oil, and 0.7-1.2 parts of tetraethyl silicate is 2-5:1-1.5:0.1-0.5:0.7-1.

2.

5. The grouting material for offshore wind power projects as described in claim 3, characterized in that, The nano-silica has a particle size of 10-20 nm and a specific surface area of ​​220-280 m². 2 / g.

6. The grouting material for offshore wind power projects as described in claim 1 or 2, characterized in that, The mineral admixture is at least one of mineral powder, fly ash, and silica fume.

7. The grouting material for offshore wind power projects as described in claim 6, characterized in that, The mineral admixture is composed of mineral powder and fly ash in a weight ratio of 5:1-3.

8. The grouting material for offshore wind power projects as described in claim 1 or 2, characterized in that, The fine aggregate is at least one of river sand, manufactured sand, and quartz sand.

9. The grouting material for offshore wind power projects as described in claim 1 or 2, characterized in that, The admixture is at least one of water-reducing agent, early-strength agent, and preservative.

10. The method for preparing grouting material for offshore wind power projects as described in any one of claims 1-9, characterized in that, The process includes the following steps: mixing cement, mineral admixtures and fine aggregates to obtain powder; then adding hydrophobic functional materials and additives to the powder and mixing them; finally adding water and mixing to obtain the grouting material for offshore wind power projects.

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