Offshore wind power grouting material and preparation method thereof

Abstract

The invention provides an offshore wind power grouting material and a preparation method thereof, and the offshore wind power grouting material is prepared from the following raw materials in parts by weight: 20 to 40 parts of cement, 10 to 20 parts of admixture, 40 to 60 parts of aggregate, 0.4 to 0.5 part of water reducing agent, 0.01 to 0.1 part of defoaming agent, 0.01 to 0.05 part of expanding agent and 0.3 to 1.2 parts of basalt composite fiber. According to the offshore wind power grouting material provided by the invention, the cement is taken as a main material, the specific active admixture, the modified expanded perlite, the quartz sand, the water reducing agent, the defoaming agent, the expanding agent and the basalt composite fiber are matched, and the comprehensive performance of the grouting material is remarkably improved through scientific proportioning design and a preparation process. The grouting material has the characteristics of micro-expansion, low apparent density, long-term stability and durability, reduces environmental pollution, can meet the strict requirements of offshore wind power, and conforms to the concept of sustainable development.

Description

Technical Field

[0001] The present invention relates to the technical field of new materials, and in particular to an offshore wind power grouting material and a preparation method thereof. Background Art

[0002] With the transformation of the global energy structure and the rapid development of renewable energy, wind power generation, as a clean and renewable energy form, has received more and more attention and application. Especially in the field of offshore wind power, due to its advantages such as abundant wind energy resources, large wind farm scale and close proximity to power load centers, offshore wind power has become an important direction for the development of global wind power. Offshore wind power base grouting material is a key material for connecting the wind turbine tower and the foundation structure, which needs to have high strength, durability and excellent construction performance. With the development of offshore wind power in deeper waters, the lightweight design of grouting material has become an important requirement for reducing costs and improving structural performance.

[0003] However, the high density of traditional grouting materials increases transportation and construction costs, and is not conducive to the lightweight design of wind turbine bases. In addition, existing low-density grouting materials generally have problems such as large shrinkage and poor corrosion resistance, which makes it difficult to meet the stringent requirements of offshore wind power.

[0004] 4. In view of this, the present invention is proposed: Due to the high density of traditional grouting materials, the transportation and construction costs are increased, which is not conducive to lightweight design and has a relatively high cost. In addition, the existing low-density grouting materials are difficult to meet the requirements of lightweight and high strength at the same time. The low-density grouting materials have a large shrinkage rate and are prone to cracks, affecting the stability of the structure. To this end, we provide a special grouting material for offshore wind power foundations and a preparation method thereof to solve the above problems. Summary of the invention

[0005] In view of the above situation, the present invention provides an offshore wind power grouting material and a preparation method thereof to solve the problems of large shrinkage and poor corrosion resistance in the prior art.

[0006] One aspect of the present invention provides an offshore wind power grouting material. The raw materials for preparing the offshore wind power grouting material include, by weight: 20-40 parts of cement, 10-20 parts of admixture, 40-60 parts of aggregate, 0.4-0.5 parts of water reducer, 0.01-0.1 parts of defoamer, 0.01-0.05 parts of expansion agent, and 0.3-1.2 parts of basalt composite fiber.

[0007] Preferably, the admixture includes 25-35 parts of microspheres, 30-40 parts of mineral powder, 15-30 parts of lithium slag powder, and 10-20 parts of silica fume, by weight.

[0008] Preferably, the microbead packing density is 0.7 kg / cm 3 , the specific surface area is 1196.0m 2 / kg, 7d activity index is 83.5%, 28d activity index is 111.3%; silica fume density is 2.24g / cm 3 , the water requirement is 124%; lithium slag powder is made by drying and ball milling lithium slag, with a density of 2.56g / cm 3 , water requirement is 105%, specific surface area is 442m 2 / kg, 28d activity index is 83%; the mineral powder is S95 grade mineral powder, the water requirement is 96%, and the density is 2.86g / cm 3 , with a specific surface area of ​​495m 2 / kg, the 7-day activity index was 95%, and the 28-day activity index was 97%.

[0009] Preferably, the aggregate includes 30-40 parts of modified expanded perlite of 10-20 mesh, 30-40 parts of quartz sand of 20-40 mesh, and 25-40 parts of quartz sand of 40-80 mesh, by weight.

[0010] Preferably, the modified expanded perlite is prepared by the following steps:

[0011] 1) Pretreatment: Wash the expanded perlite with deionized water to remove surface impurities, and then dry it at 60-80°C to constant weight;

[0012] 2) Surface activation: Soak the dried lightweight aggregate in 5% nitric acid solution or 3% sodium hydroxide solution for 1-2 hours to remove the surface inert layer and improve the surface activity;

[0013] 3) Modifier coating: first dilute the silane coupling agent into a 1-2% ethanol solution, then immerse the activated lightweight aggregate in the modifier solution, stir thoroughly to ensure that the surface is evenly coated, the coating time is 30-60 minutes, and finally take it out and place it in a 60-80°C oven to dry for 1-2 hours;

[0014] 4) Surface curing: Curing the modified lightweight aggregate at 120-150°C for 1-2 hours to allow the modifier molecules to fully react with the surface of the lightweight aggregate to form stable chemical bonds to obtain modified expanded perlite.

[0015] Preferably, the cement is P·II52.5 silicate cement.

[0016] Preferably, the water reducer is a polycarboxylate water reducer.

[0017] Preferably, the defoamer is a silicone defoamer.

[0018] Preferably, the basalt composite fiber is made of basalt fiber and aramid fiber, and is obtained by using a reinforcing rope production line and synthetic processing technology. The basalt composite fiber has an apparent diameter of 0.9 mm and a density of 1.92 g / cm 3 , elastic modulus ≥80Gpa, tensile strength ≥1800MPa.

[0019] Another aspect of the present invention provides a method for preparing the above offshore wind power grouting material, comprising the following steps:

[0020] 1) Mix cement, admixture and aggregate to obtain powder A;

[0021] 2) Mixing a water reducing agent, a defoaming agent and a swelling agent to obtain powder B;

[0022] 3) Powder A and powder B are mixed evenly, and basalt composite fiber is added to obtain mixed powder C, and then water is added to the mixed powder C according to a water-binder ratio of 0.17 to 0.21, and mixed and stirred to obtain the offshore wind power grouting material.

[0023] Compared with the prior art, the offshore wind power grouting material provided by the present invention is mainly cement, with specific active admixtures, modified expanded perlite, quartz sand, water reducer, defoamer, expander, basalt composite fiber, and through scientific ratio design and preparation process, the comprehensive performance of the grouting material is significantly improved. The grouting material has micro-expansion characteristics, low apparent density, long-term stability and durability, reduces environmental pollution, can meet the stringent requirements of offshore wind power, and conforms to the concept of sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a scanning electron microscope image of the offshore wind power grouting material in Example 1. DETAILED DESCRIPTION

[0025] In order to facilitate understanding of the present invention, the present invention will be described more fully below with reference to various embodiments, but the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0027] One embodiment of the present invention provides an offshore wind power grouting material. The raw materials for preparing the offshore wind power grouting material include, by weight: 20-40 parts of cement, 10-20 parts of admixture, 40-60 parts of aggregate, 0.4-0.5 parts of water reducer, 0.01-0.1 parts of defoamer, 0.01-0.05 parts of expansion agent, and 0.3-1.2 parts of basalt composite fiber.

[0028] In an optional embodiment of the present invention, the admixture includes 25-35 parts of microspheres, 30-40 parts of mineral powder, 15-30 parts of lithium slag powder, and 10-20 parts of silica fume by weight. The admixture plays an important role in the grouting material, and can increase the density of the grouting material, improve the interface bonding performance, increase fluidity, and improve durability and impermeability.

[0029] It should be noted that the active admixture includes any one or a combination of multiple types of mineral powder, silica fume, micro beads, and lithium slag powder, and the multiple types may be two, three, or four. The preferred combination is a combination of micro beads, mineral powder, silica fume, and lithium slag powder.

[0030] The preferred combination of microbeads, mineral powder, silica fume and lithium slag powder in the present invention can fill the gaps between cement particles, improve the density and strength of the grouting material, and the admixture can chemically react with the cement hydration product to promote the occurrence of cement secondary hydration reaction, further improving the strength and durability of the grouting material.

[0031] In an optional embodiment of the present invention, the microbead packing density is 0.7 kg / cm 3 , the specific surface area is 1196.0m 2 / kg, 7d activity index is 83.5%, 28d activity index is 111.3%; silica fume density is 2.24g / cm 3 , the water requirement is 124%; lithium slag powder is made by drying and ball milling lithium slag, with a density of 2.56g / cm 3 , water requirement is 105%, specific surface area is 442m 2 / kg, 28d activity index is 83%; the mineral powder is S95 grade mineral powder, the water requirement is 96%, and the density is 2.86g / cm 3 , with a specific surface area of ​​495m 2 / kg, the 7-day activity index was 95%, and the 28-day activity index was 97%.

[0032] In an optional embodiment of the present invention, the aggregate includes 30-40 parts of 10-20 mesh modified expanded perlite, 30-40 parts of 20-40 mesh quartz sand, and 25-40 parts of 40-80 mesh quartz sand by weight. The aggregate plays a filling role in the grouting material, and can improve the overall strength and stability of the grouting material.

[0033] By modifying the surface of expanded perlite, the interfacial bonding force between lightweight aggregate and cementitious material is significantly improved, the overall performance of the grouting material is enhanced, the modified layer effectively prevents the penetration of moisture and corrosive media, and the service life of the grouting material is extended. The modified lightweight aggregate is more evenly dispersed in the slurry, the agglomeration phenomenon is reduced, and the construction performance is improved. The modification method is simple, low-cost, and suitable for industrial production. In an optional embodiment of the present invention, the modified expanded perlite is prepared by the following steps:

[0034] 1) Pretreatment: Wash the expanded perlite with deionized water to remove surface impurities, and then dry it at 60-80°C to constant weight;

[0035] 2) Surface activation: Soak the dried lightweight aggregate in 5% nitric acid solution or 3% sodium hydroxide solution for 1-2 hours to remove the surface inert layer and improve the surface activity;

[0036] 3) Modifier coating: first dilute the silane coupling agent into a 1-2% ethanol solution, then immerse the activated lightweight aggregate in the modifier solution, stir thoroughly to ensure that the surface is evenly coated, the coating time is 30-60 minutes, and finally take it out and place it in a 60-80°C oven to dry for 1-2 hours;

[0037] 4) Surface curing: Curing the modified lightweight aggregate at 120-150°C for 1-2 hours to allow the modifier molecules to fully react with the surface of the lightweight aggregate to form stable chemical bonds to obtain modified expanded perlite.

[0038] Active groups are formed on the surface of the modified lightweight aggregate, forming chemical bonds with the cementitious material, improving the interfacial bonding force, and the modified layer effectively prevents the penetration of moisture and corrosive media, thereby improving the durability of the grouting material; the modified lightweight aggregate is more evenly dispersed in the slurry, reducing agglomeration.

[0039] In an optional embodiment of the present invention, the cement is P·II52.5 silicate cement.

[0040] In an optional embodiment of the present invention, the water reducer is a polycarboxylate water reducer, which disperses cement particles to increase cement fluidity, reduces water usage and improves strength.

[0041] In an optional embodiment of the present invention, the defoaming agent is an organosilicon defoaming agent, which can quickly reduce the surface tension of the liquid and promote the bursting of bubbles generated by the stirring of the grouting material.

[0042] In an optional embodiment of the present invention, the expansion agent is a powdered plastic expansion agent, which can expand the volume of the grouting material, compensate for the shrinkage phenomenon caused by cement hydration, reduce or prevent the shrinkage and cracking of the grouting material, and make the structure more stable.

[0043] In an optional embodiment of the present invention, the basalt composite fiber is made of basalt fiber and aramid fiber, and is obtained by using a reinforcing rope production line and a synthetic processing technology. The basalt composite fiber has an apparent diameter of 0.9 mm and a density of 1.92 g / cm 3 , elastic modulus ≥ 80Gpa, tensile strength ≥ 1800MPa. The basalt composite fiber has excellent tensile strength and acid and alkali resistance.

[0044] Another embodiment of the present invention provides a method for preparing the above offshore wind power grouting material, comprising the following steps:

[0045] 1) Mix cement, admixture and aggregate to obtain powder A;

[0046] 2) Mixing a water reducing agent, a defoaming agent and a swelling agent to obtain powder B;

[0047] 3) Powder A and powder B are mixed evenly, and basalt composite fiber is added to obtain mixed powder C, and then water is added to the mixed powder C according to a water-binder ratio of 0.17 to 0.21, and mixed and stirred to obtain the offshore wind power grouting material.

[0048] The following is a further description of the embodiments of the present invention in multiple embodiments. The embodiments of the present invention are not limited to the following specific embodiments. Within the scope of the unchanged main rights, appropriate changes can be made to the implementation.

[0049] Example 1

[0050] An offshore wind power grouting material, wherein the raw materials for preparing the offshore wind power grouting material include, by weight: 40 parts of P·Ⅱ52.5 silicate cement, 14 parts of admixture, 60 parts of aggregate, 0.4 parts of polycarboxylic acid water reducer, 0.01 parts of organosilicon defoamer, 0.01 parts of powdered plastic expansion agent, and 0.3 parts of basalt composite fiber.

[0051] Among them, by weight, the admixture includes 25 parts of microspheres, 30 parts of mineral powder, 15 parts of lithium slag powder, and 20 parts of silica fume.

[0052] The microbead packing density is 0.7 kg / cm 3 , the specific surface area is 1196.0m 2 / kg, 7d activity index is 83.5%, 28d activity index is 111.3%; silica fume density is 2.24g / cm 3 , the water requirement is 124%; lithium slag powder is made by drying and ball milling lithium slag, with a density of 2.56g / cm 3 , water requirement is 105%, specific surface area is 442m 2 / kg, 28d activity index is 83%; the mineral powder is S95 grade mineral powder, the water requirement is 96%, and the density is 2.86g / cm 3 , with a specific surface area of ​​495m 2 / kg, the 7-day activity index was 95%, and the 28-day activity index was 97%.

[0053] In terms of weight, the aggregate includes 30 parts of modified expanded perlite with a mesh size of 10 to 20, 30 parts of quartz sand with a mesh size of 20 to 40, and 40 parts of quartz sand with a mesh size of 40 to 80.

[0054] Wherein, the modified expanded perlite is prepared by the following steps:

[0055] 1) Pretreatment: Wash the expanded perlite with deionized water to remove surface impurities, and then dry it at 70°C to constant weight;

[0056] 2) Surface activation: Soak the dried lightweight aggregate in a 5% nitric acid solution for 1 hour to remove the surface inert layer and improve the surface activity;

[0057] 3) Modifier coating: first dilute the silane coupling agent into a 1% ethanol solution, then immerse the activated lightweight aggregate in the modifier solution, stir thoroughly to ensure that the surface is evenly coated, the coating time is 50 minutes, and finally take it out and place it in a 60°C oven to dry for 1 hour;

[0058] 4) Surface curing: The modified lightweight aggregate is cured at 150° C. for 1 hour to allow the modifier molecules to fully react with the surface of the lightweight aggregate to form stable chemical bonds to obtain modified expanded perlite.

[0059] The basalt composite fiber is made of basalt fiber and aramid fiber, using a reinforcing rope production line and synthetic processing technology. The basalt composite fiber has an apparent diameter of 0.9 mm and a density of 1.92 g / cm 3 , elastic modulus ≥80Gpa, tensile strength ≥1800MPa.

[0060] The method for preparing the offshore wind power grouting material comprises the following steps:

[0061] 1) Mix cement, admixture and aggregate to obtain powder A;

[0062] 2) Mixing a water reducing agent, a defoaming agent and a swelling agent to obtain powder B;

[0063] 3) After the powder A and the powder B are evenly mixed, basalt composite fiber is added to obtain a mixed powder C, and then water is added to the mixed powder C according to a water-binder ratio of 0.17 for mixing and stirring to obtain the offshore wind power grouting material.

[0064] Example 2

[0065] An offshore wind power grouting material, wherein the raw materials for preparing the offshore wind power grouting material include, by weight: 34 parts of P·Ⅱ52.5 silicate cement, 10 parts of admixture, 48 parts of aggregate, 0.46 parts of polycarboxylic acid water reducer, 0.06 parts of organosilicon defoamer, 0.03 parts of powdered plastic expansion agent, and 0.9 parts of basalt composite fiber.

[0066] Among them, by weight, the admixture includes 30 parts of microspheres, 40 parts of mineral powder, 20 parts of lithium slag powder, and 15 parts of silica fume.

[0067] The microbead packing density is 0.7 kg / cm 3 , the specific surface area is 1196.0m 2 / kg, 7d activity index is 83.5%, 28d activity index is 111.3%; silica fume density is 2.24g / cm 3 , the water requirement is 124%; lithium slag powder is made by drying and ball milling lithium slag, with a density of 2.56g / cm 3 , water requirement is 105%, specific surface area is 442m 2 / kg, 28d activity index is 83%; the mineral powder is S95 grade mineral powder, the water requirement is 96%, and the density is 2.86g / cm 3 , with a specific surface area of ​​495m 2 / kg, the 7-day activity index was 95%, and the 28-day activity index was 97%.

[0068] In terms of weight, the aggregate includes 35 parts of modified expanded perlite with a mesh size of 10 to 20, 40 parts of quartz sand with a mesh size of 20 to 40, and 30 parts of quartz sand with a mesh size of 40 to 80.

[0069] Wherein, the modified expanded perlite is prepared by the following steps:

[0070] 1) Pretreatment: Wash the expanded perlite with deionized water to remove surface impurities, and then dry it at 80°C to constant weight;

[0071] 2) Surface activation: Soak the dried lightweight aggregate in a 5% nitric acid solution for 1.5 hours to remove the surface inert layer and improve the surface activity;

[0072] 3) Modifier coating: First dilute the silane coupling agent into a 2% ethanol solution, then immerse the activated lightweight aggregate in the modifier solution, stir thoroughly to ensure that the surface is evenly coated, the coating time is 60 minutes, and finally take it out and place it in an 80°C oven to dry for 1.5 hours;

[0073] 4) Surface curing: The modified lightweight aggregate is cured at 120° C. for 2 hours to allow the modifier molecules to fully react with the surface of the lightweight aggregate to form stable chemical bonds to obtain modified expanded perlite.

[0074] The basalt composite fiber is made of basalt fiber and aramid fiber, using a reinforcing rope production line and synthetic processing technology. The basalt composite fiber has an apparent diameter of 0.9 mm and a density of 1.92 g / cm 3 , elastic modulus ≥80Gpa, tensile strength ≥1800MPa.

[0075] The method for preparing the offshore wind power grouting material comprises the following steps:

[0076] 1) Mix cement, admixture and aggregate to obtain powder A;

[0077] 2) Mixing a water reducing agent, a defoaming agent and a swelling agent to obtain powder B;

[0078] 3) After the powder A and the powder B are evenly mixed, basalt composite fiber is added to obtain a mixed powder C, and then water is added to the mixed powder C according to a water-binder ratio of 0.21, and mixed and stirred to obtain the offshore wind power grouting material.

[0079] Example 3

[0080] An offshore wind power grouting material, wherein the raw materials for preparing the offshore wind power grouting material include, by weight: 20 parts of P·Ⅱ52.5 silicate cement, 20 parts of admixture, 40 parts of aggregate, 0.5 parts of polycarboxylic acid water reducer, 0.1 parts of organosilicon defoamer, 0.05 parts of powdered plastic expansion agent, and 1.2 parts of basalt composite fiber.

[0081] Among them, calculated by weight, the admixture includes 35 parts of microspheres, 35 parts of mineral powder, 30 parts of lithium slag powder, and 10 parts of silica fume.

[0082] The microbead packing density is 0.7 kg / cm 3 , the specific surface area is 1196.0m 2 / kg, 7d activity index is 83.5%, 28d activity index is 111.3%; silica fume density is 2.24g / cm 3 , the water requirement is 124%; lithium slag powder is made by drying and ball milling lithium slag, with a density of 2.56g / cm 3 , water requirement is 105%, specific surface area is 442m 2 / kg, 28d activity index is 83%; the mineral powder is S95 grade mineral powder, the water requirement is 96%, and the density is 2.86g / cm 3 , with a specific surface area of ​​495m 2 / kg, the 7-day activity index was 95%, and the 28-day activity index was 97%.

[0083] In terms of weight, the aggregate includes 40 parts of modified expanded perlite with a mesh size of 10 to 20, 35 parts of quartz sand with a mesh size of 20 to 40, and 25 parts of quartz sand with a mesh size of 40 to 80.

[0084] Wherein, the modified expanded perlite is prepared by the following steps:

[0085] 1) Pretreatment: Wash the expanded perlite with deionized water to remove surface impurities, and then dry it at 60°C to constant weight;

[0086] 2) Surface activation: Soak the dried lightweight aggregate in a 3% sodium hydroxide solution for 2 hours to remove the surface inert layer and improve the surface activity;

[0087] 3) Modifier coating: First dilute the silane coupling agent into a 1.5% ethanol solution, then immerse the activated lightweight aggregate in the modifier solution, stir thoroughly to ensure that the surface is evenly coated, the coating time is 30 minutes, and finally take it out and place it in a 70°C oven to dry for 2 hours;

[0088] 4) Surface curing: The modified lightweight aggregate is cured at 130° C. for 1.5 hours to allow the modifier molecules to fully react with the surface of the lightweight aggregate to form stable chemical bonds, thereby obtaining modified expanded perlite.

[0089] The basalt composite fiber is made of basalt fiber and aramid fiber, using a reinforcing rope production line and synthetic processing technology. The basalt composite fiber has an apparent diameter of 0.9 mm and a density of 1.92 g / cm 3 , elastic modulus ≥80Gpa, tensile strength ≥1800MPa.

[0090] The method for preparing the offshore wind power grouting material comprises the following steps:

[0091] 1) Mix cement, admixture and aggregate to obtain powder A;

[0092] 2) Mixing a water reducing agent, a defoaming agent and a swelling agent to obtain powder B;

[0093] 3) After the powder A and the powder B are evenly mixed, basalt composite fiber is added to obtain a mixed powder C, and then water is added to the mixed powder C according to a water-binder ratio of 0.18, and the mixed powder C is mixed and stirred to obtain the offshore wind power grouting material.

[0094] Comparative Example 1

[0095] The difference from Example 1 is that lithium slag powder is not added, and the admixtures include 30 parts of mineral powder, 30 parts of microbeads, and 40 parts of silica fume, by weight.

[0096] Comparative Example 2

[0097] The difference from Example 1 is that the aggregate does not contain modified expanded perlite, and the aggregate includes, by weight: 30 parts of quartz sand of 10-20 mesh, 30 parts of quartz sand of 20-40 mesh, and 40 parts of quartz sand of 40-80 mesh.

[0098] Comparative Example 3

[0099] The difference from Example 1 is that no basalt composite fiber is added.

[0100] The performance tests of Examples 1-3 and Comparative Examples 1-3 were carried out, and the mechanical and workability tests were carried out according to the specifications GB / T50448 2015 "Technical Specifications for Application of Cement-based Grouting Materials" and JG / T408 2019 "Sleeve Grouting Materials for Steel Bar Connections". The test results are shown in Table 1 below. The sulfate erosion resistance test was carried out according to the specification GB / T500822009 "Test Methods for Long-term Performance and Durability of Ordinary Concrete". After 10% concentration of Na 2 SO 4 The test results after 15 solution erosion cycles are shown in Table 1 below.

[0101] Table 1

[0102]

[0103] It can be seen from Table 1 that the fluidity of the offshore wind power grouting materials of each embodiment of the present invention meets the standards for initial fluidity, fluidity and loss at 30 minutes. During the grouting process, it can quickly fill the gap between the foundation and the steel member under its own weight or a small pressure to ensure that the grouting is full and free of defects such as voids and bubbles. The 1d compressive strength is greater than 60MPa, the 3d compressive strength is greater than 80MPa, and the 28d compressive strength is greater than 120MPa. The vertical expansion rates are all within the standard range, that is, the vertical expansion rate of 3h is within 0.1 to 3.5, and the vertical expansion rate of 3h to 24h is within the range of 0.02 to 0.50, which meets the national standards and can compensate for the shrinkage of cement in the grouting material during the hydration process. The chloride ion diffusion coefficient is low, and it has good anti-erosion and penetration properties. The anti-sulfate erosion effect can improve its durability. Reasonable thermal conductivity helps to maintain the grouting material and the entire wind power structure within a more suitable temperature range, reducing problems such as material aging and performance degradation caused by temperature factors, thereby improving the long-term stability of the grouting material and extending the service life of offshore wind power facilities. The apparent density is reduced by about 25% compared with traditional grouting materials. Lightweight grouting materials with low apparent density can reduce the weight borne by the foundation, reduce the difficulty of foundation design and construction, and improve the stability and safety of the foundation.

[0104] In addition, it can be seen from the performance test results of each embodiment and comparative example that the fluidity of comparative example 1 without adding lithium slag is reduced, the strength of 1d, 3d, and 28d is reduced, and the sulfate erosion resistance coefficient is also reduced, indicating that the addition of lithium slag improves its strength. The active components of lithium slag can react with calcium hydroxide and other substances produced by cement hydration to produce more gels. These gels can fill pores, refine the pore size, and make the internal structure of the grouting material more compact, thereby improving the later strength of the grouting material. In comparative example 2, all aggregates are quartz sand instead of light aggregate modified expanded perlite, and its thermal conductivity is increased, and the apparent density is also increased, indicating that the modified expanded perlite can improve its lightweight and thermal insulation performance when the material meets the strength requirements. In Comparative Example 3, no basalt composite fiber is added, and its fluidity is improved, but the strength and sulfate corrosion resistance of the grouting material are reduced. This is because the basalt composite fiber has high strength and modulus, and can form a reinforced skeleton inside the grouting material to prevent the expansion and penetration of internal microcracks, reduce the pores and microcracks inside the grouting material, and improve its density, thereby increasing the strength of the grouting material and reducing the permeability of the grouting material.

[0105] Further, please combine Figure 1 It can be seen that at the age of 28 days, the grouting material has formed a very dense, uniform and stable structure, and the components are closely combined, showing a high degree of integrity. The calcium silicate hydrate gel forms a very dense and intricate network structure without obvious pore structure, completely covering the entire observation area and becoming the dominant structural morphology. The calcium aluminate crystals are fully developed and fill the pores very fully. They are intertwined and synergistic with the calcium silicate hydrate gel, further enhancing the density and stability of the structure. The cement hydration products attached to the surface of the basalt fiber can improve the bonding performance between the basalt fiber and the grouting material matrix. The good bonding can effectively transfer the stress between the basalt fiber and the matrix. The basalt fiber can play a bridging and crack-blocking role. When microcracks appear in the matrix, the fiber can span the two ends of the crack to prevent the further expansion of the crack, so that the growth of the crack width and length is limited, thereby improving the mechanical properties of the grouting material.

[0106] The present invention ingeniously adds lithium slag as an active admixture into the grouting material, uses modified expanded perlite to replace part of the quartz sand to reduce the apparent density and thermal conductivity of the grouting material, and then adds basalt composite fiber on this basis for improvement, thereby inventing a green, environmentally friendly, low-density, high-strength grouting material with good resistance to seawater erosion.

[0107] In summary, the offshore wind power grouting material provided by the present invention is mainly cement, with specific active admixtures, modified expanded perlite, quartz sand, water reducer, defoamer, expander, basalt composite fiber, and through scientific ratio design and preparation process, the comprehensive performance of the grouting material is significantly improved. The grouting material has micro-expansion characteristics, low apparent density, long-term stability and durability, reduces environmental pollution, can meet the stringent requirements of offshore wind power, and is in line with the concept of sustainable development.

[0108] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An offshore wind power grouting material, characterized in that: Measured by weight, the raw materials for preparing the offshore wind power grouting material include: 20-40 parts of cement, 10-20 parts of admixture, 40-60 parts of aggregate, 0.4-0.5 parts of water reducer, 0.01-0.1 parts of defoamer, 0.01-0.05 parts of expansion agent, and 0.3-1.2 parts of basalt composite fiber.

2. The offshore wind power grouting material according to claim 1, characterized in that: In terms of weight, the admixture includes 25-35 parts of microspheres, 30-40 parts of mineral powder, 15-30 parts of lithium slag powder, and 10-20 parts of silica fume.

3. The offshore wind power grouting material according to claim 2, characterized in that: The microbead packing density is 0.7 kg / cm 3 , the specific surface area is 1196.0m 2 / kg, 7d activity index is 83.5%, 28d activity index is 111.3%; silica fume density is 2.24g / cm 3 , the water requirement is 124%; lithium slag powder is made by drying and ball milling lithium slag, with a density of 2.56g / cm 3 , water requirement is 105%, specific surface area is 442m 2 / kg, 28d activity index is 83%; the mineral powder is S95 grade mineral powder, the water requirement is 96%, and the density is 2.86g / cm 3 , with a specific surface area of ​​495m 2 / kg, the 7-day activity index was 95%, and the 28-day activity index was 97%.

4. The offshore wind power grouting material according to claim 1, characterized in that: In terms of weight, the aggregate includes 30-40 parts of modified expanded perlite with a mesh size of 10 to 20, 30-40 parts of quartz sand with a mesh size of 20 to 40, and 25-40 parts of quartz sand with a mesh size of 40 to 80.

5. The offshore wind power grouting material according to claim 4, characterized in that: The modified expanded perlite is prepared by the following steps: 1) Pretreatment: Wash the expanded perlite with deionized water to remove surface impurities, and then dry it at 60-80°C to constant weight; 2) Surface activation: Soak the dried lightweight aggregate in 5% nitric acid solution or 3% sodium hydroxide solution for 1-2 hours to remove the surface inert layer and improve the surface activity; 3) Modifier coating: first dilute the silane coupling agent into a 1-2% ethanol solution, then immerse the activated lightweight aggregate in the modifier solution, stir thoroughly to ensure that the surface is evenly coated, the coating time is 30-60 minutes, and finally take it out and place it in a 60-80°C oven to dry for 1-2 hours; 4) Surface curing: Curing the modified lightweight aggregate at 120-150°C for 1-2 hours to allow the modifier molecules to fully react with the surface of the lightweight aggregate to form stable chemical bonds to obtain modified expanded perlite.

6. The offshore wind power grouting material according to claim 1, characterized in that: The cement is P·Ⅱ52.5 silicate cement.

7. The offshore wind power grouting material according to claim 1, characterized in that: The water reducer is a polycarboxylate water reducer.

8. The offshore wind power grouting material according to claim 1, characterized in that: The defoamer is an organosilicon defoamer.

9. The offshore wind power grouting material according to claim 1, characterized in that: The basalt composite fiber is made of basalt fiber and aramid fiber, and is obtained by using a reinforcing rope production line and synthetic processing technology. The basalt composite fiber has an appearance diameter of 0.9 mm and a density of 1.92 g / cm 3 , elastic modulus ≥80Gpa, tensile strength ≥1800MPa.

10. The method for preparing the offshore wind power grouting material according to any one of claims 1 to 9, characterized in that: The following steps are involved: 1) Mix cement, admixture and aggregate to obtain powder A; 2) Mixing a water reducing agent, a defoaming agent and a swelling agent to obtain powder B; 3) Powder A and powder B are mixed evenly, and basalt composite fiber is added to obtain mixed powder C, and then water is added to the mixed powder C according to a water-binder ratio of 0.17 to 0.21, and mixed and stirred to obtain the offshore wind power grouting material.

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