Homologous isomeric alkaline residue-based fluidized stabilized soil as well as preparation method and application of homologous isomeric alkaline residue-based fluidized stabilized soil

Abstract

The invention provides homologous and isomeric alkaline residue-based fluidized stabilized soil as well as a preparation method and application thereof, and belongs to the technical field of solid waste resource utilization. The alkali residue-based curing agent is prepared from the alkali residue after filter pressing, the slag, the desulfurized fly ash, the fly ash and the cement. According to the method, high-water-content pasty raw alkali residues, alkali residues obtained after desalination and salt fixation and furnace slag are used as the alkali residue-based matrix soil. The homologous and isomeric alkaline residues are different in structure and form, so that the homologous and isomeric alkaline residues can be used as matrix soil on one hand, and can be used for preparing the curing agent on the other hand, and physical and chemical reaction and particle size matching among different components are promoted and improved, so that the mechanical property of the homologous and isomeric alkaline residue-based fluid-state solidified soil is improved. By adding a proper amount of water and water reducing agent, the fluidity of the homologous isomeric alkaline residue-based fluid-state solidified soil can be adjusted, the construction requirement can be met, and excellent dense pouring performance is achieved.

Description

Technical Field

[0001] This invention relates to the field of solid waste resource utilization technology, and in particular to a homologous and heterogeneous alkaline slag-based fluidized solidified soil, its preparation method, and its application. Background Technology

[0002] Offshore pile foundations are widely used in projects such as offshore wind power, cross-sea bridges, port terminals, and offshore oil platforms. However, due to the unique characteristics of the marine environment, offshore pile foundations are subject to long-term erosion from tides and waves, as well as the deposition and corrosion of marine silt, which can easily lead to a decrease in the stability and bearing capacity of the pile foundations. This seriously affects the safety and service life of offshore facilities. Traditional methods for reinforcing offshore pile foundations include concrete reinforcement and sleeve-type protective structures, but these methods generally suffer from problems such as complex construction, high costs, insufficient environmental adaptability, and difficult maintenance, making it difficult to meet the needs of marine engineering for efficient, economical, and sustainable erosion-resistant technologies.

[0003] Fluidized solidified soil is a self-leveling, self-compacting, and strength-controllable material with a wide range of raw materials. Its self-leveling and self-compacting properties make it suitable for underwater construction and irregular terrain, effectively improving construction efficiency and reducing project costs. Therefore, fluidized solidified soil has great application potential in areas such as marine pile foundation reinforcement and underwater backfilling.

[0004] The ammonia-soda process is the main industrial process for producing soda ash, widely used in glass manufacturing, chemical, food, and pharmaceutical industries. This process generates a large amount of soda ash residue. However, traditional landfill and stockpiling methods not only result in low utilization rates (≤5%) but also negatively impact the surrounding environment (soil salinization, dust pollution, etc.). Soda ash residue, due to its high calcium content, fine particle size, high pH, ​​and high activity, can be used to prepare fluidized bed solidified soil. However, different forms of soda ash residue coexist in soda ash stockpiles, including high-moisture, paste-like raw soda ash residue, filtered soda ash residue with a certain moisture content, and soda ash residue after deep desalination and salt fixation treatment. These residues all originate from the waste residue generated during the ammonia-soda process for soda ash production and share a common origin. However, due to differences in treatment processes and methods, their physical and chemical structures differ, thus exhibiting heterogeneity. These soda ash residues are referred to as homologous heterogeneous soda ash residues. The preparation of homologous and heterogeneous alkaline slag-based fluidized solidified soil using these alkaline slags has promising applications in replacing or partially replacing traditional marine pile foundation scour protection projects. However, due to the differences in properties between the homologous and heterogeneous alkaline slags, it is currently difficult to directly use them in marine pile foundation scour protection projects. Summary of the Invention

[0005] The purpose of this invention is to provide a homologous heterogeneous alkali slag-based fluidized solidified soil, its preparation method, and its application. The homologous heterogeneous alkali slag-based fluidized solidified soil provided by this invention can be used for high-value applications of homologous heterogeneous alkali slag.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a homologous heterogeneous alkaline slag-based fluidized solidified soil, wherein the fluidity of the homologous heterogeneous alkaline slag-based fluidized solidified soil is 170~400mm; The homologous and heterogeneous alkaline slag-based fluidized solidified soil comprises the following components: alkaline slag-based matrix soil, alkaline slag-based solidifying agent, water-reducing agent, and water; the mass ratio of the alkaline slag-based matrix soil to the alkaline slag-based solidifying agent is 100:(10~30). Based on a mass percentage of 100%, the components of the alkali slag-based matrix soil include: 40-50% paste-like raw alkali slag, 20-30% desalinated and salt-fixed alkali slag, and 20-40% slag. Based on a mass percentage of 100%, the components of the alkali slag-based curing agent include: 25-40% alkali slag after pressure filtration, 35-50% slag, 10-15% desulfurization ash, 10-15% fly ash, and 10-15% cement.

[0007] Preferably, the moisture content of the paste-like raw alkali residue is ≥200%.

[0008] Preferably, the particle size of the alkaline residue after desalination and salt fixation is ≤5mm.

[0009] Preferably, the moisture content of the alkaline residue after filter pressing is ≤50%.

[0010] Preferably, the slag includes water-quenched blast furnace slag.

[0011] Preferably, the fly ash is Grade I fly ash.

[0012] Preferably, the specific surface area of ​​the alkali slag-based curing agent is 300~400m². 2 / kg, with a fineness of not less than 5% residue on a 45μm square-hole sieve.

[0013] This invention also provides a method for preparing the homologous isomeric alkali slag-based fluidized solidified soil described in the above technical solution, comprising the following steps: The paste-like original alkali residue, the desalinated and salt-fixed alkali residue, and the furnace slag are mixed to obtain alkali residue-based matrix soil; Alkali residue after filter pressing, slag, desulfurization ash, fly ash and cement are mixed to obtain an alkali residue-based curing agent; The alkaline slag-based matrix soil, the alkaline slag-based solidifying agent, the water-reducing agent, and water are mixed to obtain homogeneous and heterogeneous alkaline slag-based fluidized solidified soil.

[0014] The present invention also provides the application of the homologous heterogeneous alkaline slag-based fluidized solidified soil described in the above technical solution or the homologous heterogeneous alkaline slag-based fluidized solidified soil prepared by the preparation method described in the above technical solution in scour protection piles.

[0015] Preferably, the method of application includes: pumping homologous isomeric alkali slag-based fluidized solidified soil to the root of the scour-resistant protective pile, and forming a protective layer after hardening around the root of the pile.

[0016] This invention provides a homologous heterogeneous alkali slag-based fluidized solidified soil, wherein the fluidity of the homologous heterogeneous alkali slag-based fluidized solidified soil is 170~400mm; the homologous heterogeneous alkali slag-based fluidized solidified soil comprises the following components: alkali slag-based matrix soil, alkali slag-based solidifying agent, water-reducing agent, and water; the mass ratio of the alkali slag-based matrix soil to the alkali slag-based solidifying agent is 100:(10~30); based on the mass percentage of the alkali slag-based matrix soil being 100%, the components of the alkali slag-based matrix soil include: 40~50% paste-like original alkali slag, 20~30% desalination and salt-fixing alkali slag, and 20~40% slag; based on the mass percentage of the alkali slag-based solidifying agent being 100%, the components of the alkali slag-based solidifying agent include: 25~40% filter-pressed alkali slag, 35~50% slag, 10~15% desulfurization ash, 10~15% fly ash, and 10~15% cement. This invention prepares alkali-based solidifying agents and alkali-based matrix soils from homologous heterogeneous alkali slags of different forms and structures but originating from the same source. These solidifying agents and matrix soils are then used to form a fluidized solidified soil. The alkali-based solidifying agent is prepared using filter-pressed alkali slag, slag, desulfurization ash, fly ash, and cement. The matrix soil is prepared using paste-like raw alkali slag, desalinated and solidified alkali slag, and slag. The different structures and morphologies of the homologous heterogeneous alkali slags allow them to function as both matrix soil and solidifying agents, promoting and enhancing the physicochemical reactions and particle size distribution between different components, thereby improving the mechanical properties of the homologous heterogeneous alkali slag-based fluidized solidified soil. By adding appropriate amounts of water and water-reducing agents, the fluidity of the homologous heterogeneous alkali slag-based fluidized solidified soil can be adjusted to meet construction requirements and exhibit excellent compaction performance. The results of the examples show that the 28-day compressive strength of the homologous alkali slag-based fluidized solidified soil provided by the present invention is above 3.4 MPa, which indicates that it has high strength and stability. Attached Figure Description

[0017] Figure 1 Images of homologous alkaline residue used in embodiments of the present invention; Figure 2 This is a schematic diagram illustrating the application of homologous isomeric alkali slag-based fluidized solidified soil in an embodiment of the present invention; Figure 3 The image shows a scaled-down model test of the scour protection of wind power monopile foundations using homologous isomorphic alkaline slag-based fluidized solidified soil as described in Example 1 of this invention. Detailed Implementation

[0018] This invention provides a homologous heterogeneous alkaline slag-based fluidized solidified soil, wherein the fluidity of the homologous heterogeneous alkaline slag-based fluidized solidified soil is 170~400mm; The homologous and heterogeneous alkaline slag-based fluidized solidified soil comprises the following components: alkaline slag-based matrix soil, alkaline slag-based solidifying agent, water-reducing agent, and water; the mass ratio of the alkaline slag-based matrix soil to the alkaline slag-based solidifying agent is 100:(10~30). Based on a mass percentage of 100%, the components of the alkali slag-based matrix soil include: 40-50% paste-like raw alkali slag, 20-30% desalinated and salt-fixed alkali slag, and 20-40% slag. Based on a mass percentage of 100%, the components of the alkali slag-based curing agent include: 25-40% alkali slag after pressure filtration, 35-50% slag, 10-15% desulfurization ash, 10-15% fly ash, and 10-15% cement.

[0019] In this invention, the flowability of the homologous heterogeneous alkali slag-based fluidized solidified soil is 170~400mm. As one embodiment of this invention, the flowability of the homologous heterogeneous alkali slag-based fluidized solidified soil can be 170mm, 200mm, 250mm, 300mm, or 350mm. This invention controls the flowability of the homologous heterogeneous alkali slag-based fluidized solidified soil within the above range, resulting in better flowability, improved casting efficiency, and facilitates filling of target spaces, reducing voids, honeycomb, and pitting defects, thus ensuring the compactness and continuity of the filling.

[0020] The homologous and heterogeneous alkaline slag-based fluidized solidified soil provided by the present invention comprises the following components: alkaline slag-based matrix soil, alkaline slag-based solidifying agent, water-reducing agent, and water.

[0021] In this invention, the mass ratio of the alkali slag-based matrix soil to the alkali slag-based solidifying agent is 100:(10~30), preferably 100:(15~20).

[0022] The present invention does not have a special limitation on the amount of water used, but can be adjusted as needed to make the fluidity of the homologous isomeric alkali slag-based fluidized solidified soil reach 170~400mm.

[0023] The homologous and heterogeneous alkaline slag-based fluidized solidified soil provided by the present invention includes alkaline slag-based matrix soil.

[0024] Based on a mass percentage of 100% for the alkali slag-based matrix soil, the alkali slag-based matrix soil comprises 40-50% paste-like raw alkali slag. In one embodiment of the present invention, the mass percentage of the paste-like raw alkali slag can be 40%, 42%, 45%, 48%, or 50%.

[0025] In this invention, the moisture content of the paste-like raw alkali residue is preferably ≥200%. This invention does not specifically limit the source of the paste-like raw alkali residue; conventional paste-like raw alkali residue can be used. In an embodiment of this invention, the paste-like raw alkali residue can be the liquid waste residue generated after the ammonia-soda process for preparing sodium carbonate, which is directly discharged into the alkali residue pond and obtained through natural sedimentation and evaporation. The paste-like raw alkali residue used in this invention has a high moisture content, which can reduce water consumption. In an embodiment of this invention, the source of the paste-like raw alkali residue can be the alkali residue stockpile of China Nuclear Ecological Environment Co., Ltd., and the main components of the paste-like raw alkali residue include calcium carbonate, calcium sulfate, calcium hydroxide, sodium salts, and magnesium salts.

[0026] In an embodiment of the present invention, the image of the paste-like original alkali residue is preferably as shown in the image below. Figure 1 As shown in (a).

[0027] Based on a mass percentage of 100% for the alkali slag-based matrix soil, the alkali slag-based matrix soil comprises 20-30% alkali slag after desalination and salt fixation. In one embodiment of the present invention, the mass percentage of the alkali slag after desalination and salt fixation can be 20%, 22%, 25%, 26%, 28%, or 30%. The use of alkali slag after desalination and salt fixation in this invention can promote pozzolanic reaction. By controlling the mass percentage of alkali slag after desalination and salt fixation within the above-mentioned range, this invention can improve the strength of the homologous alkali slag-based fluidized solidified soil after solidification.

[0028] In this invention, the particle size of the alkaline residue after desalination and salt fixation is preferably ≤5mm, more preferably ≤3mm. By controlling the particle size of the alkaline residue within the above range, this invention enables it to form a gradation with other particles in the homologous and heterogeneous alkaline residue-based fluidized solidified soil, thereby improving the strength of the solidified homologous and heterogeneous alkaline residue-based fluidized solidified soil. In embodiments of this invention, the preferred image of the alkaline residue after desalination and salt fixation is as follows: Figure 1 As shown in (c).

[0029] This invention does not specifically limit the source of the alkaline residue after desalination and salt fixation. It can use alkaline residue well-known to those skilled in the art, provided it is homologous to the paste-like original alkaline residue described in the above technical solution. In the embodiments of this invention, the alkaline residue after desalination and salt fixation is preferably sourced from Lianyungang CNNC Ecological Environment Co., Ltd.

[0030] Based on a mass percentage of 100% for the alkali slag-based matrix soil, the alkali slag-based matrix soil comprises 20-40% slag. In one embodiment of the invention, the mass percentage of the slag can be 20%, 22%, 25%, 30%, 35%, or 40%. The use of slag in this invention promotes pozzolanic reaction. By controlling the mass percentage of slag within the aforementioned range, this invention can improve the strength of the homologous alkali slag-based fluidized solidified soil after solidification. This invention does not specifically limit the source of the slag; conventional slag can be used. In an embodiment of the invention, the slag can be ash discharged from the bottom of the boiler after coal combustion.

[0031] In this invention, the fineness of the slag is preferably greater than 45% on a 15μm square hole sieve and less than 5mm in particle size.

[0032] The homologous alkali slag-based fluidized solidified soil provided by this invention includes an alkali slag-based solidifying agent.

[0033] In this invention, the alkali slag-based solidifying agent comprises 25-40% alkali slag after pressure filtration. Based on a 100% mass percentage of the alkali slag-based solidifying agent, in this invention, the component of the alkali slag-based solidifying agent includes 25-40% alkali slag after filter pressing. As one embodiment of this invention, the mass percentage of the alkali slag after filter pressing can be 25%, 30%, 32%, 35%, 36%, 38%, or 40%. This invention, by adding alkali slag after filter pressing, which has a low moisture content, can promote the solidification of the alkali slag-based matrix soil. In an embodiment of this invention, the preferred image of the alkali slag after filter pressing is as shown below. Figure 1 As shown in (b).

[0034] In this invention, the moisture content of the alkaline residue after pressure filtration is preferably ≤50%, and more preferably ≤40%.

[0035] In this invention, the preferred method for preparing the alkali residue after pressure filtration includes reducing the moisture content of the paste-like raw alkali residue to ≤50%. This invention does not specifically limit the method for reducing the moisture content; conventional pressure filtration is sufficient.

[0036] In this invention, the particle size of the alkaline residue after pressure filtration is preferably ≤1mm, and more preferably ≤0.5mm.

[0037] Based on a mass percentage of 100% for the alkali slag-based curing agent, in this invention, the component of the alkali slag-based curing agent includes 35-50% slag. As one embodiment of this invention, the mass percentage of slag can be 35%, 40%, 42%, 45%, 46%, 48%, or 50%. This invention, by adding slag, can promote the pozzolanic reaction.

[0038] In this invention, the slag is preferably water-quenched blast furnace slag, and the grade of the water-quenched blast furnace slag can be S95. In the embodiments of this invention, the chemical composition of the water-quenched blast furnace slag preferably includes CaO 35.325%, SiO2 30.985%, Al2O3 17.519%, and MgO 10.364%.

[0039] Based on a 100% mass percentage of the alkali slag-based curing agent, in this invention, the alkali slag-based curing agent comprises 10-15% desulfurization ash. As one embodiment of this invention, the mass percentage of the desulfurization ash can be 10%, 11%, 12%, 13%, 14%, or 15%. This invention, by adding desulfurization ash, can improve the long-term strength of homologous alkali slag-based fluidized solidified soil after curing. This invention does not specifically limit the source of the desulfurization ash; conventional desulfurization ash can be used.

[0040] Based on a mass percentage of 100% for the alkali slag-based curing agent, in this invention, the component of the alkali slag-based curing agent includes 10-15% fly ash. As one embodiment of this invention, the mass percentage of the primary fly ash can be 10%, 11%, 12%, 13%, 14%, or 15%. In this invention, the fly ash is preferably primary fly ash. By adding primary fly ash, this invention can promote pozzolanic reaction and improve the strength of the homologous alkali slag-based fluidized solidified soil after curing.

[0041] In this invention, the specific surface area of ​​the alkali slag-based curing agent is preferably 300-400 m². 2 / kg, more preferably 350~400m 2 / kg. In this invention, the fineness of the alkali slag-based solidifying agent is preferably such that the residue on a 45μm square-hole sieve is not less than 5%. The homologous alkali slag-based fluidized solidified soil provided by this invention includes a water-reducing agent. In this invention, the water-reducing agent is preferably a polycarboxylate high-efficiency liquid water-reducing agent, and the model of the polycarboxylate high-efficiency liquid water-reducing agent can be FED-1S polycarboxylate high-performance water-reducing agent (standard type).

[0042] In this invention, the cement is preferably 42.5 ordinary Portland cement. This invention improves the cementitious properties and early strength of homologous alkali slag-based fluidized solidified soil by adding cement.

[0043] This invention also provides a method for preparing the homologous isomeric alkali slag-based fluidized solidified soil described in the above technical solution, comprising the following steps: The paste-like original alkali residue, the desalinated and salt-fixed alkali residue, and the furnace slag are mixed to obtain alkali residue-based matrix soil; Alkali residue after filter pressing, slag, desulfurization ash, fly ash and cement are mixed to obtain an alkali residue-based curing agent; The alkaline slag-based matrix soil, the alkaline slag-based solidifying agent, the water-reducing agent, and water are mixed to obtain homogeneous and heterogeneous alkaline slag-based fluidized solidified soil.

[0044] This invention mixes paste-like raw alkali residue, desalinated and solidified alkali residue, and furnace slag to obtain alkali residue-based matrix soil. This invention does not specifically limit the method of mixing the paste-like raw alkali residue, desalinated and solidified alkali residue, and furnace slag; any method that ensures the three are mixed evenly is acceptable.

[0045] This invention mixes alkali residue after pressure filtration, slag, desulfurization ash, fly ash and cement to obtain an alkali residue-based curing agent.

[0046] The present invention does not have any particular limitation on the method of mixing the alkali residue after pressure filtration, slag, desulfurization ash, fly ash and cement, as long as the alkali residue-based solidifier is mixed evenly.

[0047] After obtaining the alkali slag-based matrix soil and the alkali slag-based solidifying agent, the present invention mixes the alkali slag-based matrix soil, the alkali slag-based solidifying agent, the water-reducing agent and water to obtain homologous heterogeneous alkali slag-based fluidized solidified soil.

[0048] In this invention, the preferred method for mixing the alkali slag-based matrix soil, alkali slag-based solidifying agent, water-reducing agent, and water is stirring. The stirring speed can be 70~90 r / min, more preferably 80~90 r / min; and the stirring time can be 3~4 min.

[0049] This invention preferably involves mixing alkali-based matrix soil, alkali-based solidifying agent, water, and water-reducing agent to adjust the fluidity of the homologous alkali-based fluidized solidified soil. In this invention, the water-reducing agent is preferably a polycarboxylate high-efficiency liquid water-reducing agent, and the model of the polycarboxylate high-efficiency liquid water-reducing agent can be FED-1S polycarboxylate high-performance water-reducing agent (standard type).

[0050] The present invention also provides the application of the homologous heterogeneous alkaline slag-based fluidized solidified soil described in the above technical solution or the homologous heterogeneous alkaline slag-based fluidized solidified soil prepared by the preparation method described in the above technical solution in scour protection piles.

[0051] In this invention, the preferred method of application includes: pumping homologous isomorphic alkali slag-based fluidized solidified soil to the root of the scour-resistant protective pile, and hardening the soil around the root of the pile to form a protective layer.

[0052] The present invention does not have a special limitation on the amount of homologous and heterogeneous alkaline slag-based fluidized solidified soil. It can be adjusted as needed to form a protective layer on the outside of the pile root and the amount can be adjusted accordingly.

[0053] In this invention, the method for forming the protective layer preferably includes feather protection, flatbed protection, wing protection, or bottom protection.

[0054] This invention does not specifically limit the curing conditions, as long as the homologous heterogeneous alkali slag-based fluidized solidified soil is completely cured. In embodiments of this invention, the curing can involve a first curing and a second curing, wherein the temperature for the first and second curing is independently preferably 20±5℃; and the humidity for the first and second curing is independently preferably 95±5%. In embodiments of this invention, the first curing time can be 1 day. This invention achieves final shaping through the first curing. In embodiments of this invention, the second curing time can be 3~28 days. This invention enables the homologous heterogeneous alkali slag-based fluidized solidified soil to be fully cured through the second curing.

[0055] The present invention, when cured under the above conditions, enables the homologous and heterogeneous alkali slag-based fluidized solidified soil to be fully solidified.

[0056] In this invention, the preferred schematic diagram of the application of the homologous isomorphic alkali slag-based fluidized solidified soil is as follows: Figure 2 As shown. From Figure 2 As can be seen, the experimental procedure of the present invention is as follows: using alkali residue after filter pressing, slag, desulfurization ash, fly ash and cement as alkali residue-based solidifying agents; using paste-like original alkali residue, desalinated and solidified alkali residue and slag as matrix soil, mixing evenly, adding water-reducing agent and water and stirring evenly, conducting flowability tests, and then molding and curing (i.e. molding and demolding, curing in a standard curing room).

[0057] The homologous and heterogeneous alkali slag-based fluidized solidified soil provided by this invention is conducive to promoting the high-value utilization of alkali slag, reducing the environmental impact of alkali slag storage, and effectively realizing dense casting in marine environments.

[0058] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0059] Example 1 A homologous heterogeneous alkali slag-based fluidized solidified soil, wherein the fluidity of the homologous heterogeneous alkali slag-based fluidized solidified soil is 300 mm; The components of the homologous and heterogeneous alkaline slag-based fluidized solidified soil are: alkaline slag-based matrix soil, alkaline slag-based solidifying agent, water-reducing agent (FED-1S polycarboxylate high-performance water-reducing agent (standard type)) and water; the mass ratio of the alkaline slag-based matrix soil to the alkaline slag-based solidifying agent is 100:10. Based on the mass percentage of the alkali slag-based matrix soil being 100%, the composition of the alkali slag-based matrix soil is as follows: 50% of the original alkali slag in paste form with a water content ≥200%, 30% of the alkali slag after desalination and salt fixation (particle size ≤5mm), and 20% of the slag. Based on the mass percentage of the alkali slag-based curing agent being 100%, the components of the alkali slag-based curing agent are: 30% alkali slag after pressure filtration (particle size ≤ 5 mm, moisture content 40%), 40% slag (S95), 10% desulfurization ash, 10% grade I fly ash, and 10% cement.

[0060] The preparation method of the homologous isomeric alkali slag-based fluidized solidified soil is as follows: The paste-like original alkali residue, the desalinated and salt-fixed alkali residue, and the furnace slag are mixed to obtain alkali residue-based matrix soil; Alkali residue after filter pressing, slag, desulfurization ash, primary fly ash and cement are mixed to obtain alkali residue-based solidifier; The alkali slag-based matrix soil and the alkali slag-based curing agent are stirred at 90 r / min for 3 min. Water is added to the mixture, and the amount of water is determined according to the fluidity index. Water is added until the basic fluidity is 170 mm. Polycarboxylate high-efficiency liquid water-reducing agent is added, and the amount is 0.5~1.0% of the dry alkali slag-based curing agent. The fluidity is increased to 300 mm. Stir for 2 min to obtain homologous heterogeneous alkali slag-based fluidized solidified soil.

[0061] Application Example 1 A scaled-down model of a wind turbine monopile foundation with scour protection was prepared in the laboratory to simulate the application of homologous heterogeneous alkaline slag-based fluidized solidified soil in scour protection piles. The homologous heterogeneous alkaline slag-based fluidized solidified soil prepared in Example 1 was layered and filled into a mold. After thorough vibration and compaction until all voids were eliminated (i.e., compaction), the specimen was covered with a film and placed in a standard curing room (temperature: 20±5℃, humidity 95±5%) for curing. After one day, the specimen was demolded and placed back in the standard curing room (temperature: 20±5℃, humidity 95±5%) for curing for 3 days, 7 days, and 28 days, respectively. Finally, compressive strength tests were conducted, and the compressive strengths at 3 days, 7 days, and 28 days were measured to be 0.62 MPa, 1.05 MPa, and 3.4 MPa, respectively.

[0062] Table 1. Test results of homologous alkali slag-based fluidized solidified soil prepared in Example 1

[0063] Example 2 A homologous isomeric alkali slag-based fluidized solidified soil, wherein the fluidity of the homologous isomeric alkali slag-based fluidized solidified soil is 260 mm; The components of the homologous and heterogeneous alkaline slag-based fluidized solidified soil are: alkaline slag-based matrix soil, alkaline slag-based solidifying agent, water-reducing agent (FED-1S polycarboxylate high-performance water-reducing agent (standard type)) and water; the mass ratio of the alkaline slag-based matrix soil to the alkaline slag-based solidifying agent is 100:15. Based on the mass percentage of the alkali slag-based matrix soil being 100%, the composition of the alkali slag-based matrix soil is as follows: 40% of the original alkali slag in paste form with a water content ≥200%, 30% of the alkali slag after desalination and salt fixation (particle size ≤5mm), and 30% of the slag. Based on the mass percentage of the alkali slag-based curing agent being 100%, the components of the alkali slag-based curing agent are: 30% alkali slag after pressure filtration (particle size ≤ 5 mm, moisture content 40%), 35% slag (S95), 10% desulfurization ash, 10% grade I fly ash, and 15% cement.

[0064] The preparation method of the homologous isomeric alkali slag-based fluidized solidified soil is as follows: The paste-like original alkali residue, the desalinated and salt-fixed alkali residue, and the furnace slag are mixed to obtain alkali residue-based matrix soil; Alkali residue after filter pressing, slag, desulfurization ash, primary fly ash and cement are mixed to obtain alkali residue-based solidifier; The alkali slag-based matrix soil and the alkali slag-based curing agent are stirred at 90 r / min for 3 min. Water is added to the mixture, and the amount of water is determined according to the fluidity index. Water is added until the basic fluidity is 170 mm. Polycarboxylate high-efficiency liquid water-reducing agent is added, and the amount is 1% of the dry alkali slag-based curing agent. The fluidity is increased to 260 mm. Stir for 2 min to obtain homologous heterogeneous alkali slag-based fluidized solidified soil.

[0065] Application Example 2 The homologous alkali slag-based fluidized solidified soil prepared in Example 1 was layered and filled into the mold. After thorough vibration and compaction until all voids were eliminated, the specimens were covered with a film and placed in a standard curing room (temperature: 20±5℃, humidity: 95±5%) for curing. After one day, the specimens were demolded and placed back in the standard curing room (temperature: 20±5℃, humidity: 95±5%) for curing for 3 days, 7 days, and 28 days, respectively. Finally, compressive strength tests were conducted, and the compressive strengths at 3 days, 7 days, and 28 days were measured to be 0.75 MPa, 1.3 MPa, and 3.6 MPa, respectively.

[0066] Table 2. Test results of homologous alkali slag-based fluidized solidified soil prepared in Example 2

[0067] Application Example 3 The homologous heterogeneous alkaline slag-based fluidized solidified soil prepared in Example 1 was used to conduct a scaled-down model test of the scour protection of wind power monopile foundations. The method was as follows: the homologous heterogeneous alkaline slag-based fluidized solidified soil prepared in Example 1 was used to pump the alkaline slag-based fluidized solidified soil to the bottom of the scaled-down model pile using four common scour protection modes (feather protection, flat bed protection, wing protection, and bottom protection) through a pipeline pump, and artificial waves were used for scour.

[0068] Photos of scaled-down model tests of wind turbine monopile foundation scour protection using homogeneous alkali slag-based fluidized solidified soil are shown below. Figure 3 As shown. From Figure 3 It can be seen that the homologous isomeric alkaline slag anti-scour pile fluidized solidified soil prepared in Example 1 of the present invention has a good anti-scour protection effect on wind power monopile foundations.

[0069] Comparative Example A fluidized solidified soil, wherein the solidifying agent composition of the fluidized solidified soil is: 35% cement, 15% slag, 40% nickel slag, 5% fly ash, and 5% sodium hydroxide, by mass percentage.

[0070] The water-reducing agent is FED-1S polycarboxylate high-performance water-reducing agent (standard type), and the water-reducing agent accounts for 2% of the mass percentage of the curing agent.

[0071] The substrate soil is loess with a particle size ≤5mm.

[0072] The mass ratio of the matrix to the curing agent is 100:15. The preparation method of the fluidized solidified soil is as follows: cement, slag, nickel slag, fly ash and sodium hydroxide are mixed to obtain a solidifying agent; The matrix soil and the alkali slag-based curing agent are stirred at 90 r / min for 3 min. Water is added to the mixture, and the amount of water is determined according to the fluidity index. Water is added until the basic fluidity is 170 mm. Polycarboxylate high-efficiency liquid water-reducing agent is added, and the amount is 2% of the dry curing agent. The fluidity is increased to 280 mm. Stir for 2 min to obtain the fluidized cured soil.

[0073] The fluidized solidified soil prepared in Comparative Example 1 was layered and filled into the mold. After thorough vibration until all voids were eliminated, the specimens were covered with a film and placed in a standard curing chamber (temperature: 20±5℃, humidity: 95±5%) for curing. After one day, the specimens were demolded and then placed back in the standard curing chamber (temperature: 20±5℃, humidity: 95±5%) for curing at 3 days, 7 days, and 28 days, respectively. Finally, compressive strength tests were conducted, and the measured compressive strengths at 3 days, 7 days, and 28 days were 0.42 MPa, 0.58 MPa, and 0.78 MPa, respectively.

[0074] Table 3. Test results of the fluidized solidified soil prepared in Comparative Example 1

[0075] The results above show that the homologous heterogeneous alkali slag-based fluidized solidified soil provided by this invention exhibits high strength and stability after solidification. This is because this invention prepares alkali slag-based solidifying agents and alkali slag-based matrix soils from homologous heterogeneous alkali slags of different forms and structures but originating from the same source, and then uses the alkali slag-based solidifying agent to solidify the alkali slag-based matrix soil, forming fluidized solidified soil. This invention prepares alkali slag-based solidifying agents using filtered alkali slag, slag, desulfurization ash, fly ash, and cement. This invention uses high-moisture-content paste-like original alkali slag, desalinated and solidified alkali slag, and slag as alkali slag-based matrix soils. The different structures and forms of the homologous heterogeneous alkali slags utilized in this invention can serve as both matrix soils and solidifying agents, promoting and improving the physicochemical reactions and particle size distribution between different components, thereby improving the mechanical properties of the homologous heterogeneous alkali slag-based fluidized solidified soil. This invention can adjust the fluidity of the homologous heterogeneous alkali slag-based fluidized solidified soil by adding appropriate amounts of water and water-reducing agents, meeting construction requirements and exhibiting excellent compaction performance.

[0076] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A homologous and heterogeneous alkali slag-based fluidized solidified soil, characterized in that, The fluidity of the homologous alkali slag-based fluidized solidified soil is 170~400mm; The homologous and heterogeneous alkaline slag-based fluidized solidified soil comprises the following components: alkaline slag-based matrix soil, alkaline slag-based solidifying agent, water-reducing agent, and water; the mass ratio of the alkaline slag-based matrix soil to the alkaline slag-based solidifying agent is 100:(10~30). Based on a mass percentage of 100%, the components of the alkali slag-based matrix soil include: 40-50% paste-like raw alkali slag, 20-30% desalinated and salt-fixed alkali slag, and 20-40% slag. Based on a mass percentage of 100%, the components of the alkali slag-based curing agent include: 25-40% alkali slag after pressure filtration, 35-50% slag, 10-15% desulfurization ash, 10-15% fly ash, and 10-15% cement.

2. The homologous alkali slag-based fluidized solidified soil according to claim 1, characterized in that, The moisture content of the paste-like raw alkali residue is ≥200%.

3. The homologous alkali slag-based fluidized solidified soil according to claim 1, characterized in that, The particle size of the alkaline residue after desalination and salt fixation is ≤5mm.

4. The homologous alkali slag-based fluidized solidified soil according to claim 1, characterized in that, The moisture content of the alkaline residue after filter pressing is ≤50%.

5. The homologous alkali slag-based fluidized solidified soil according to claim 1, characterized in that, The slag includes water-quenched blast furnace slag.

6. The homologous alkali slag-based fluidized solidified soil according to claim 1, characterized in that, The fly ash is grade I fly ash.

7. The homologous alkali slag-based fluidized solidified soil according to claim 1, characterized in that, The specific surface area of ​​the alkali slag-based curing agent is 300~400 m². 2 / kg, with a fineness of not less than 5% residue on a 45μm square-hole sieve.

8. A method for preparing the homologous isomeric alkali slag-based fluidized solidified soil according to any one of claims 1 to 7, comprising the following steps: The paste-like original alkali residue, the desalinated and salt-fixed alkali residue, and the furnace slag are mixed to obtain alkali residue-based matrix soil; Alkali residue after filter pressing, slag, desulfurization ash, fly ash and cement are mixed to obtain an alkali residue-based curing agent; The alkaline slag-based matrix soil, the alkaline slag-based solidifying agent, the water-reducing agent, and water are mixed to obtain homologous and heterogeneous alkaline slag-based fluidized solidified soil.

9. The application of the homologous heterogeneous alkaline slag-based fluidized solidified soil according to any one of claims 1 to 7 or the homologous heterogeneous alkaline slag-based fluidized solidified soil prepared by the preparation method according to claim 8 in scour protection piles.

10. The application according to claim 9, characterized in that, The method of application includes: pumping homologous isomeric alkaline slag-based fluidized solidified soil to the root of the scour-resistant protective pile, and forming a protective layer after hardening around the root of the pile.

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