Solid waste-based premixed fluidized solidified soil and preparation method thereof

Abstract

The application relates to the field of solidified soil, and particularly discloses a solid-waste-based premixed fluidized solidified soil and a preparation method thereof. The solid-waste-based premixed fluidized solidified soil comprises soil, water and a solidifying agent in a weight ratio of (28-36):(50-54):(6-9); the solidifying agent comprises the following components in parts by weight based on the total weight of the solidifying agent: 20-40 parts of fly ash, 30-47 parts of slag, 6-18 parts of silica ash, 10-15 parts of sea silt, 1-3 parts of a water reducing agent, 1-3 parts of sodium hydroxide, 1-3 parts of calcium sulfoaluminate, 3-10 parts of a fiber reinforced material and 1-3 parts of a phosphate. The application can avoid the problems of excessive stress concentration and excessive shrinkage of the solidified soil in the hydration process, thereby reducing the cracking of the solidified soil after the premixed fluidized solidification.

Description

Technical Field

[0001] This invention relates to the technical field of solidified soil, and in particular to a premixed fluidized solidified soil based on solid waste and its preparation method. Background Technology

[0002] Premixed fluidized solidified soil is a type of engineering material that is made by fully utilizing marine silt, waste foundation soil and slag after foundation pit excavation, and other materials to dispose of the waste soil on site. A certain proportion of special cementitious materials (solidifying agents) and water are added, and then the mixture is uniformly mixed through a series of processes and special machinery to form a self-leveling, self-compacting, and pumpable engineering material. After pouring or filling and curing, it is solidified into a new type of geotechnical engineering material with certain strength, impermeability and long-term stability.

[0003] In related technologies, a method for preparing fluidized solidified soil using construction waste is disclosed, including the preparation of a special solidification admixture and the preparation of fluidized solidified soil. The preparation method of fluidized solidified soil includes the following steps: 1) Prepare construction waste excavated from construction projects, selecting uncontaminated soil that meets the relevant heavy metal and pollution limit standards of "Screening Values ​​and Control Values ​​for Soil Pollution Risk of Construction Land" (kgB36600-2018) and "Soil Testing Series Standards" (NY / T1121-2006), with the soil containing the fewest stones. 1) The maximum particle size should be ≤10mm; 2) Excavate and set up a mud soaking tank in the backfilling area, soak the soil with water in proportion for 1-2 days, and after 2 days, use the mud soaking tank to break up the mud blocks to prepare mud slurry; 3) Build a mixing tank below the mud soaking tank, add the proportion of solidifying admixture to the mud slurry from the soaking tank above, and use the mud soaking tank and excavator to mix evenly to obtain the fluidized solidified soil of the present invention; the slag, solidifying admixture, and water are mixed in a weight ratio of 35-40:5-10:55-60. The solidifying admixture is composed of fly ash, slag, quicklime, calcined kaolin, sodium silicate, sodium sulfate, and polyether organosilicon defoamer.

[0004] Because the curing additive contains components such as quicklime, it may generate significant shrinkage stress during the hydration process, leading to material cracking and affecting the overall integrity of the structure. Summary of the Invention

[0005] To reduce cracking of premixed fluidized bed solidified soil, this application provides a solid waste-based premixed fluidized bed solidified soil and its preparation method.

[0006] In the first aspect, this application provides a premixed fluidized solidified soil based on solid waste, employing the following technical solution:

[0007] A premixed fluidized solidified soil based on solid waste comprises soil, water, and a solidifying agent in a weight ratio of (28-36):(50-54):(6-9); the solidifying agent comprises the following components by weight parts: 20-40 parts fly ash, 30-47 parts slag, 6-18 parts silica fume, 10-15 parts marine silt, 1-3 parts water-reducing agent, 1-3 parts sodium hydroxide, 1-3 parts calcium sulfoaluminate, 3-10 parts fiber reinforcing material, and 1-3 parts phosphate.

[0008] By adopting the above technical solutions and using the aforementioned proportions of soil, water, and solidifying agent, a pre-mixed fluidized solidified soil with excellent flowability can be obtained. Fly ash, being a fine particle, can provide a fine particle filling effect, enhancing the material's density. Slag, as an auxiliary component of the cementitious material, can improve the later-stage strength of the solidified soil. Silica fume, a highly active siliceous material, can promote hydration reactions and improve the early-stage strength of the material; the water-reducing agent can lower the water-cement ratio, improving the fluidity and workability of the slurry. Marine silt has good binding and plasticity, containing abundant minerals and trace elements, and can play multiple roles such as bonding, filling, and improving rheological properties. Therefore, using these four solid wastes in combination with the water-reducing agent can improve the early-stage strength, later-stage strength, and density of the solidified soil, giving it good workability before solidification and good durability after solidification. Sodium hydroxide is used to activate the slag and fly ash, accelerating the hydration reaction process. Calcium sulfoaluminate compensates for shrinkage during hydration, reducing the risk of cracking. Fiber-reinforced materials can improve the material's toughness and crack resistance. Phosphate controls the hydration reaction rate, preventing excessively rapid hydration from causing temperature stress concentration and cracking. Therefore, by using the above-mentioned proportions of sodium hydroxide, calcium sulfoaluminate, fiber reinforcement materials, and phosphate in synergy, the problems of excessive stress concentration and excessive shrinkage in the solidified soil during hydration can be avoided, thereby reducing cracking of the solidified soil after premixed fluid solidification.

[0009] In one specific implementation, the curing agent further includes the following component in parts by weight: 0.2-0.6 parts of water glass powder.

[0010] By adopting the above technical solution, water glass powder can be quickly dissolved in water. In the solidified soil, water glass and sodium hydroxide can react to form silica gel. These gel substances have strong adhesive force and can tightly bind soil particles together. The gel substances can also fill the pores between soil particles, which helps to improve the density and strength of the solidified soil, thereby reducing cracking of the solidified soil and improving its durability.

[0011] In one specific implementation, the curing agent further includes tartaric acid.

[0012] By employing the above technical solution, tartaric acid acts as a pH regulator and complexing agent in the curing agent. The acidity of tartaric acid neutralizes some of the strong alkalinity of sodium hydroxide, maintaining the pH of the cured soil within a suitable range, which is beneficial for the chemical reactions between the components. Simultaneously, tartaric acid can also undergo a complexation reaction with silicate ions in water glass to form stable complexes. These complexes can fill the pores between soil particles, increasing the density of the cured soil and reducing cracking.

[0013] In one specific implementation, the curing agent further includes the following component in parts by weight: 1-3 parts of nano-calcium carbonate.

[0014] By employing the above-mentioned technical solution, nano-calcium carbonate, with its extremely small particle size, can effectively fill the tiny pores in the solidified soil, promoting the hydration reaction of cement and other cementitious materials, generating more hydration products, and thus improving the strength of the solidified soil. Furthermore, the high specific surface area and activity of nano-calcium carbonate enable it to form a good interfacial bond with soil particles and cement particles. This interfacial optimization enhances the adhesion between the components, allowing the solidified soil to better maintain its integrity under external forces.

[0015] In one specific implementation, the curing agent further includes the following component in parts by weight: 1-3 parts of polyacrylate.

[0016] By employing the above technical solutions, polyacrylate can effectively disperse soil particles in fluidized solidified soil, increasing the viscosity of the solidified soil and giving it better rheological properties, thus preventing particle aggregation and settling. This helps reduce the flow and collapse of solidified soil during construction, improving construction efficiency and quality.

[0017] In one specific implementation, the fiber reinforcement material includes at least one of polypropylene fibers or carbon fibers.

[0018] By adopting the above technical solutions, polypropylene fibers or carbon fibers can effectively bear and transfer loads, cross micro-cracks in the solidified soil, prevent further expansion of cracks through bridging, and improve the bearing capacity, deformation resistance and crack resistance of the solidified soil. Polypropylene fibers or carbon fibers can also increase the toughness and ductility of the solidified soil, enabling it to better absorb energy when subjected to impact or vibration, reduce brittle failure, and thus reduce cracking after solidification.

[0019] In one specific implementation, the fly ash has a particle size of 28-44 μm, the slag has a particle size of 124-138 μm, and the silica fume has a particle size of 50-200 nm.

[0020] By adopting the above technical solution, this application found through experiments that by controlling the particle size of fly ash, slag and silica fume within the above range, the solidified soil obtained has higher strength and density after solidification, which can further prevent the solidified soil from cracking.

[0021] Secondly, this application provides a method for preparing premixed fluidized solidified soil based on solid waste, using the following technical solution:

[0022] A method for preparing premixed fluidized solidified soil based on solid waste includes the following steps:

[0023] The curing agent is obtained by uniformly mixing fly ash, slag, silica fume, marine silt, water-reducing agent, sodium hydroxide, calcium sulfoaluminate, fiber reinforcement material and phosphate.

[0024] Weigh out the soil, water and solidifying agent according to the proportions. Mix the soil and water evenly and let it stand for 24-48 hours. Then stir it evenly to obtain a slurry. Mix the slurry and solidifying agent evenly to obtain solid waste base premixed fluidized solidified soil.

[0025] By adopting the above technical solution, soaking and mixing the soil in water first helps to reduce the particle size of the soil in the slurry, resulting in a more uniform slurry. Furthermore, it avoids the components in the solidifying agent reacting with water to form gel components, which helps to further improve the fluidity, uniformity, and post-solidification strength of the premixed fluidized bed solidified soil based on solid waste.

[0026] In summary, this application has the following beneficial effects:

[0027] 1. This application can avoid the problem of excessive stress concentration and excessive shrinkage in the solidified soil during the hydration process, thereby reducing the cracking of the solidified soil after the premixed fluid solidification.

[0028] 2. In this application, water glass powder, tartaric acid and polyacrylate are preferred, which can undergo complexation reaction with silicate ions in water glass to generate stable complexes. These complexes can fill the pores between soil particles, improve the compaction of the solidified soil and reduce cracking of the solidified soil. Detailed Implementation

[0029] The present application will be further described in detail below with reference to embodiments and comparative examples.

[0030] This embodiment provides a premixed fluidized solidified soil based on solid waste, comprising soil, water, and solidifying agent in a weight ratio of 32:52:7.

[0031] The curing agent consists of the following components: 32 kg of fly ash with a particle size of 28-44 μm, 35 kg of slag with a particle size of 124-138 μm, 18 kg of silica fume with a particle size of 50-200 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), and 2 kg of calcium phosphate.

[0032] This embodiment also provides a method for preparing premixed fluidized solidified soil based on solid waste, which includes the following steps:

[0033] According to the formula, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber and calcium phosphate are mixed evenly to obtain a curing agent;

[0034] Weigh out the soil, water and solidifying agent according to the proportions. Mix the soil and water evenly and let stand for 36 hours. Then stir evenly to obtain mud. Mix the mud with the solidifying agent and stir until even to obtain solid waste base premixed fluid solidified soil.

[0035] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 20 kg of fly ash with a particle size of 34-38 μm, 40 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 10 kg of marine silt with a particle size of 0.1-0.5 mm, 3 kg of PCE-11 type polycarboxylate superplasticizer, 3 kg of sodium hydroxide, 3 kg of calcium sulfoaluminate, 10 kg of polypropylene fiber (Hongyao HY-444), and 3 kg of calcium phosphate.

[0036] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 40 kg of fly ash with a particle size of 34-38 μm, 47 kg of slag with a particle size of 128-132 μm, 6 kg of silica fume with a particle size of 120-160 nm, 15 kg of marine silt with a particle size of 0.1-0.5 mm, 1 kg of PCE-11 type polycarboxylate superplasticizer, 1 kg of sodium hydroxide, 1 kg of calcium sulfoaluminate, 3 kg of polypropylene fiber (Hongyao HY-444), and 1 kg of calcium phosphate.

[0037] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 40 kg of fly ash with a particle size of 34-38 μm, 30 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 15 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 4 kg of polypropylene fiber (Hongyao HY-444), and 2 kg of calcium phosphate.

[0038] The only difference between this embodiment and Embodiment 1 is that the weight ratio of soil, water and curing agent is 28:50:6.

[0039] The only difference between this embodiment and Embodiment 1 is that the weight ratio of soil, water and curing agent is 36:54:9.

[0040] The only difference between this embodiment and Embodiment 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 0.4 kg of water glass powder (CAS No.: 1344-09-8, 120 mesh). In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and water glass powder are mixed evenly according to the proportion to obtain the curing agent.

[0041] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 0.2 kg of water glass powder (CAS No.: 1344-09-8, 120 mesh). In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and water glass powder are mixed evenly according to the proportion to obtain the curing agent.

[0042] The only difference between this embodiment and Embodiment 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 0.6 kg of water glass powder (CAS No.: 1344-09-8, 120 mesh). In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and water glass powder are mixed evenly according to the proportion to obtain the curing agent.

[0043] The difference between this embodiment and Embodiment 1 lies only in that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, 0.4 kg of water glass powder (CAS No.: 1344-09-8, 120 mesh), and 0.3 kg of tartaric acid. In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, water glass powder, and tartaric acid are mixed evenly according to the proportion to obtain the curing agent.

[0044] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 2 kg of nano-calcium carbonate (Liangde Nano D-3000A). In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and nano-calcium carbonate are mixed evenly according to the proportions to obtain the curing agent.

[0045] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 1 kg of nano-calcium carbonate (Liangde Nano D-3000A). In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and nano-calcium carbonate are mixed evenly according to the proportions to obtain the curing agent.

[0046] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 3 kg of nano-calcium carbonate (Liangde Nano D-3000A). In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and nano-calcium carbonate are mixed evenly according to the proportions to obtain the curing agent.

[0047] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, 0.4 kg of water glass powder (CAS No.: 1344-09-8, 120 mesh), 0.3 kg of tartaric acid, and 2 kg of nano calcium carbonate (Liangde Nano D-3000A). In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, water glass powder, tartaric acid and nano calcium carbonate are mixed evenly according to the proportion to obtain the solidifying agent.

[0048] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 2 kg of sodium polyacrylate (Juhe BiokgB29948). In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and sodium polyacrylate are mixed evenly according to the proportion to obtain the curing agent.

[0049] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 1 kg of sodium polyacrylate (Juhe BiokgB29948). In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and sodium polyacrylate are mixed evenly according to the proportion to obtain the curing agent.

[0050] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, and 3 kg of sodium polyacrylate (Juhe BiokgB29948). In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, and sodium polyacrylate are mixed evenly according to the proportion to obtain the curing agent.

[0051] The only difference between this embodiment and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 34-38 μm, 35 kg of slag with a particle size of 128-132 μm, 18 kg of silica fume with a particle size of 120-160 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), 2 kg of calcium phosphate, 0.4 kg of water glass powder (CAS No.: 1344-09-8, 120 mesh), 0.3 kg of tartaric acid, 2 kg of nano calcium carbonate (Liangde Nano D-3000A), and 3 kg of sodium polyacrylate (Juhe Bio kgB29948). In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, polypropylene fiber, calcium phosphate, water glass powder, tartaric acid, nano calcium carbonate and sodium polyacrylate are mixed evenly according to the proportion to obtain the solidifying agent.

[0052] The only difference between this embodiment and Embodiment 1 is that the particle size of the fly ash is 20-28 μm, the particle size of the slag is 114-124 μm, and the particle size of the silica fume is 15-45 nm.

[0053] The only difference between this embodiment and Embodiment 1 is that the particle size of the fly ash is 46-58μm, the particle size of the slag is 140-154μm, and the particle size of the silica fume is 210-300nm.

[0054] Comparative Example

[0055] Comparative Example 1

[0056] The only difference between this comparative example and Example 1 is that the weight ratio of soil, water and curing agent is 26:48:5.

[0057] Comparative Example 2

[0058] The only difference between this comparative example and Example 1 is that the weight ratio of soil, water and curing agent is 38:56:10.

[0059] Comparative Example 3

[0060] The only difference between this comparative example and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 28-44 μm, 35 kg of slag with a particle size of 124-138 μm, 18 kg of silica fume with a particle size of 50-200 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 4 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of calcium sulfoaluminate, 7 kg of polypropylene fiber (Hongyao HY-444), and 2 kg of calcium phosphate. In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, calcium sulfoaluminate, polypropylene fiber, and calcium phosphate are mixed evenly according to the proportions to obtain the curing agent.

[0061] Comparative Example 4

[0062] The only difference between this comparative example and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 28-44 μm, 35 kg of slag with a particle size of 124-138 μm, 18 kg of silica fume with a particle size of 50-200 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 4 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 7 kg of polypropylene fiber (Hongyao HY-444), and 2 kg of calcium phosphate. In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, polypropylene fiber, and calcium phosphate are mixed evenly according to the proportions to obtain the curing agent.

[0063] Comparative Example 5

[0064] The only difference between this comparative example and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 28-44 μm, 42 kg of slag with a particle size of 124-138 μm, 18 kg of silica fume with a particle size of 50-200 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 2 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, and 2 kg of calcium phosphate. In the preparation method of premixed fluidized solidified soil based on solid waste, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, and calcium phosphate are mixed evenly according to the proportions to obtain the curing agent.

[0065] Comparative Example 6

[0066] The only difference between this comparative example and Example 1 is that the curing agent uses the following components: 32 kg of fly ash with a particle size of 28-44 μm, 35 kg of slag with a particle size of 124-138 μm, 18 kg of silica fume with a particle size of 50-200 nm, 12.5 kg of marine silt with a particle size of 0.1-0.5 mm, 4 kg of PCE-11 type polycarboxylate superplasticizer, 2 kg of sodium hydroxide, 2 kg of calcium sulfoaluminate, and 7 kg of polypropylene fiber (Hongyao HY-444). In the preparation method of solid waste-based premixed fluidized solidified soil, fly ash, slag, silica fume, marine silt, polycarboxylate superplasticizer, sodium hydroxide, calcium sulfoaluminate, and polypropylene fiber are mixed evenly according to the proportions to obtain the curing agent.

[0067] Performance testing

[0068] For the solid waste-based premixed fluidized bed soil samples prepared in Examples 1-20 and Comparative Examples 1-6, the initial slump, 7-day compressive strength, and 7-day drying shrinkage were tested according to T / BkgEA001-2019 "Technical Standard for Premixed Fluidized Bed Soil Filling Engineering".

[0069] The test results are shown in Table 1.

[0070] Table 1

[0071] Group Initial slump / mm 7d compressive strength / MPa 7-day shrinkage rate / % Example 1 230 6.8 0.24 Example 2 224 6.2 0.28 Example 3 234 7 0.26 Example 4 231 6.4 0.25 Example 5 220 6.4 0.28 Example 6 236 6.0 0.29 Example 7 222 7.4 0.16 Example 8 225 7.1 0.21 Example 9 220 7.6 0.15 Example 10 220 7.9 0.13 Example 11 223 7.7 0.20 Example 12 226 7.4 0.22 Example 13 221 7.8 0.18 Example 14 218 9.4 0.10 Example 15 226 7.0 0.22 Example 16 228 6.9 0.23 Example 17 225 7.1 0.20 Example 18 216 9.6 0.08 Example 19 224 6.4 0.29 Example 20 242 7.1 0.22 Comparative Example 1 214 6.2 0.34 Comparative Example 2 238 5.7 0.31 Comparative Example 3 213 4.6 1.24 Comparative Example 4 215 4.8 1.36 Comparative Example 5 218 5.2 0.94 Comparative Example 6 207 3.2 1.62

[0072] Combining Examples 1, 5-6 and Comparative Examples 1-2 with Table 1, it can be seen that compared with Example 1, the initial slump and 7-day compressive strength of Comparative Examples 1-2 are significantly reduced, while the 7-day drying shrinkage rate is significantly increased. This indicates that using the weight ratio range of soil, water and curing agent in Examples 1, 5-6 helps to improve the fluidity and compressive strength of the cured soil and reduce the drying shrinkage rate, thereby helping to reduce cracking of premixed fluidized cured soil.

[0073] Combining Example 1 and Comparative Examples 3-6 with Table 1, it can be seen that compared with Example 1, the initial slump and 7-day compressive strength of Comparative Examples 3-6 are significantly reduced, while the 7-day shrinkage rate is significantly increased. This indicates that only by following the raw material ratio of Example 1, i.e., using sodium hydroxide, calcium sulfoaluminate, polypropylene fiber and calcium phosphate simultaneously, can the effects of improving the fluidity and compressive strength of the solidified soil and reducing the shrinkage rate be achieved.

[0074] As can be seen from Examples 1-4 and Table 1, Examples 1-4 all have high initial slump and 7-day compressive strength, and low 7-day drying shrinkage. This indicates that using the raw material ratios within the range of Examples 1-4 can help reduce cracking of premixed fluidized solidified soil.

[0075] Combining Examples 1 and 7-18 with Table 1, it can be seen that compared with Example 1, Examples 7-18 show smaller changes in initial slump, increased 7-day compressive strength, and decreased 7-day drying shrinkage. This indicates that the addition of water glass powder, tartaric acid, nano-calcium carbonate, and polyacrylate to the curing agent helps to further reduce cracking of premixed fluidized solidified soil.

[0076] Combining Examples 1 and 19-20 with Table 1, it can be seen that compared to Example 1, Example 19 has a smaller initial slump and 7-day compressive strength, and a larger 7-day drying shrinkage rate; while Example 20 has a larger initial slump and 7-day compressive strength, and a smaller 7-day drying shrinkage rate. This indicates that using the filler particle size of Example 1 helps reduce cracking of the premixed fluidized bed and enhances its compactness.

[0077] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A premixed fluidized solidified soil based on solid waste, characterized in that, The mixture comprises soil, water, and a curing agent in a weight ratio of (28-36):(50-54):(6-9); the curing agent comprises the following components in parts by weight: 20-40 parts fly ash, 30-47 parts slag, 6-18 parts silica fume, 10-15 parts marine silt, 1-3 parts water-reducing agent, 1-3 parts sodium hydroxide, 1-3 parts calcium sulfoaluminate, 3-10 parts fiber-reinforcing material, 1-3 parts phosphate, 0.2-0.6 parts water glass powder, 0.3 parts tartaric acid, 1-3 parts nano calcium carbonate, and 1-3 parts polyacrylate. The fiber reinforcing material is polypropylene fiber, and the phosphate is calcium phosphate; the particle size of the fly ash is 28-44 μm, the particle size of the slag is 124-138 μm, and the particle size of the silica fume is 50-200 nm; the preparation method of the solid waste-based premixed fluidized solidified soil includes the following steps: mixing fly ash, slag, silica fume, water-reducing agent, sodium hydroxide, calcium sulfoaluminate, fiber reinforcing material, and phosphate evenly to obtain a solidifying agent; weighing soil, water, and solidifying agent according to proportions, mixing soil and water evenly, letting stand for 24-48 hours, then stirring evenly to obtain slurry, and mixing the slurry and solidifying agent evenly to obtain solid waste-based premixed fluidized solidified soil.