An anti-freezing soil stabilizer for weathered slag soil and a preparation method thereof

Abstract

The present application relates to the technical field of soil consolidation agent, and specifically discloses a soil consolidation agent for anti-freezing weathered slag soil, which is prepared from the following raw materials in parts by mass: steel slag 5-25 parts, red mud 2-8 parts, fly ash 20-50 parts, power plant slag 3-25 parts, limestone powder 5-15 parts, shale 1-5 parts, reinforcing filler 3-8 parts, titanium gypsum 3-8 parts, sodium humate 1-2 parts, carbodiimide 0.01-0.1 part, N-hydroxysuccinimide 1-2 parts, gelatin 5-15 parts, chitosan 1-2 parts, calcium chloride 1-2 parts, slow-release urea 1-10 parts, sodium sulfate 0.2-2 parts, urease 0.2-3 parts, potassium hydroxide 0.1-3 parts, sodium silicate 3-10 parts, and dispersant 1.5-3 parts. The present application also discloses a preparation method and a use method of the soil consolidation agent for anti-freezing weathered slag soil.

Description

Technical Field

[0001] This invention relates to the field of soil-cement solidification agents, and in particular to a soil-cement solidification agent for frost-resistant weathered stone slag and its preparation method. Background Technology

[0002] Weathered stone slag is a product of surface rock weathering. Its durability is worse than that of ordinary soil, and its physical and mechanical properties are less stable. Currently, weathered stone slag is only piled up and simply landfilled, which has a relatively serious impact on the atmosphere, soil, and water quality.

[0003] Soil-cement-rock solidification agents are additives that, through a series of reactions with the soil, significantly improve its physicochemical properties. These agents can be used to reinforce various foundation soils and can also adjust soil strength according to engineering needs. The application of existing solidification agents can reduce the amount of cement and aggregate used, saving costs and minimizing environmental damage, thus playing a positive role in sustainable development and ecological protection. The application of solidification agents to weathered stone slag soil shows great promise for future research.

[0004] Currently, research on curing agents mainly uses materials such as cement, lime, and fly ash for curing alone or in combination. However, after weathered slag soil hardens, it is very easy to cause poor volume stability, generate many fine cracks, and the structure is prone to cracking. At the same time, it has poor resistance to frost cracking and the curing effect is not obvious.

[0005] In view of the above, how to develop a solidifying agent for weathered stone waste soil to improve the resource utilization level of weathered stone waste soil while enhancing its strength and frost crack resistance has become an urgent technical problem to be solved. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a frost-resistant weathered stone slag solidifying agent and its preparation method.

[0007] A frost-resistant weathered stone slag soil solidifying agent, the raw materials of which, by weight, include: 5-25 parts steel slag, 2-8 parts red mud, 20-50 parts fly ash, 3-25 parts power plant slag, 5-15 parts limestone powder, 1-5 parts shale, 3-8 parts reinforcing filler, 3-8 parts titanium gypsum, 1-2 parts sodium humate, 0.01-0.1 parts carbodiimide, 1-2 parts N-hydroxysuccinimide, 5-15 parts gelatin, 1-2 parts chitosan, 1-2 parts calcium chloride, 1-10 parts slow-release urea, 0.2-2 parts sodium sulfate, 0.2-3 parts urease, 0.1-3 parts potassium hydroxide, 3-10 parts sodium silicate, and 1.5-3 parts dispersant.

[0008] Preferably, the slow-release urea is prepared by the following specific steps: heating water to 50-60℃, adding polyvinyl alcohol and sodium dodecylbenzenesulfonate while stirring, stirring for 5-15 minutes, adding γ-polyglutamic acid and continuing to stir for 10-20 minutes, adjusting the pH of the system to 6-6.4, spraying it onto the surface of urea particles, and drying.

[0009] More preferably, the mass ratio of polyvinyl alcohol, sodium dodecylbenzenesulfonate, γ-polyglutamic acid, and urea particles is 0.01-0.1:0.01-0.1:1-2:5-10.

[0010] When cracks appear in the soil-concrete-rock solidified soil system, slow-release urea can slowly release urea and work with urease to decompose the slow-release urea and form carbonate ions. Under the action of calcium ions in the system, calcium carbonate precipitate can be formed and further fill the cracks. Combined with the self-healing reinforced filler, the system has an excellent self-healing effect, good durability and impermeability, and effectively ensures the soil's resistance to frost cracking.

[0011] Preferably, the reinforcing filler is prepared by the following specific steps: hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, and triethanolamine are added to water and stirred at 60-70°C for 1-2 hours. While stirring, terminal amino polyamide amine and tetraethyl orthosilicate are added, followed by the addition of saturated ammonia water and stirring for another 10-20 hours. The mixture is then filtered, washed, and freeze-dried.

[0012] More preferably, the mass ratio of hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, triethanolamine, amino-terminated polyamide amine, tetraethyl orthosilicate, and saturated ammonia is 1-2:1-2:2-6:1-5:5-10:1-5.

[0013] This invention utilizes a compound of hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, and triethanolamine to form micelles, which promotes the deposition of regular nanoparticles on the structural surface of macromolecular-terminal amino polyamide amines in nano-silica. This results in products with ultra-high specific surface area and self-healing reinforcing filler, leading to better solidification of weathered stone slag and allowing for better penetration into the system structure to form dendritic branches, effectively enhancing the product's resistance to frost cracking.

[0014] Meanwhile, because the reinforcing filler contains a large number of positively charged amino groups, it can electrostatically adsorb with the self-healing reinforcing filler under the action of potassium hydroxide, which promotes further improvement of the curing effect. It can also work with the calcium carbonate deposition during the curing process to effectively fill the pores in the system, resulting in excellent anti-freeze cracking performance of the product.

[0015] Preferably, the dispersant is at least one of lignosulfonate, dodecyl sulfonate, and polyacrylate.

[0016] The preparation method of the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0017] S1. Steel slag, red mud, fly ash, power plant slag, limestone powder, shale, reinforcing filler, and titanium gypsum are ball-milled to obtain powder.

[0018] S2. Disperse sodium humate in water, add carbodiimide and N-hydroxysuccinimide, stir at 40-50℃ for 5-15 min, add gelatin and chitosan and continue stirring for 1-4 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler;

[0019] S3. Mix the powder and self-healing reinforcing filler, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate and dispersant and stir evenly.

[0020] Preferably, in S1, the ball milling speed is 2000-4000 rpm, the ball milling time is 30-60 min, and the ball-to-material ratio is 3-5:1.

[0021] Preferably, in S1, the specific surface area of ​​the powder is ≥500-600 m². 2 / kg.

[0022] Preferably, in S2, the mass ratio of sodium humate to water is 1-2:20-30.

[0023] The method of using the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0024] (1) Dry the weathered stone slag;

[0025] (2) Add the frost-resistant weathered stone slag solidifying agent to the sun-dried weathered stone slag and mix evenly. The mass ratio of the frost-resistant weathered stone slag solidifying agent to the sun-dried weathered stone slag is 3-12:100.

[0026] Preferably, in step (1), the weathered stone slag is dried until its moisture content is ≤10%.

[0027] Beneficial effects:

[0028] This invention grafts sodium humate onto gelatin and then combines it with powder. Not only is the dispersion uniformity excellent, but the calcium ion crosslinking forms a well-developed and stable crosslinked network in the system. This network not only absorbs free water from weathered stone and soil and has good plasticity, but the resulting cementing components also effectively bind the weathered stone and soil. This significantly enhances the weathered stone and soil's resistance to erosion and freeze-thaw cycles, and makes it easier to compact and process.

[0029] The gel of this invention can effectively fill the pores between weathered stone slag particles and effectively overcome volume shrinkage after hardening. Even when cracks appear on the surface, under certain dry and wet cycle stimulation, the reversibility of the coordination bonds between sodium humate, chitosan and calcium ions and their absorption and expansion properties can promote the shrinkage of cracks. It has a strong self-repairing ability and effectively ensures the soil's resistance to frost cracking.

[0030] This invention is applicable to stone slag soil with different degrees of weathering. The soil-coagulating rock solidifier stabilizes weathered stone slag soil, making it high-strength, durable, and impermeable. It also has excellent frost resistance and crack resistance. At the same time, it improves the resource utilization level of solid wastes such as steel slag, red mud, fly ash, and power plant slag, reduces resource consumption, lowers production costs, reduces road construction costs, and is also beneficial to environmental protection. Attached Figure Description

[0031] Figure 1 The image shows a comparison of the compressive strength of the solidified soil obtained in Example 5 and Comparative Examples 1-2 after 7 days and 28 days of curing.

[0032] Figure 2 This is a comparison diagram of the displacement of the solidified soil obtained in Example 5 and Comparative Examples 1-2 under a 200kN load.

[0033] Figure 3 This is a comparison chart showing the mass loss of solidified soil obtained in Example 5 and Comparative Examples 1-2 after different freeze-thaw cycles. Detailed Implementation

[0034] The present invention will be further explained below with reference to specific embodiments.

[0035] Example 1

[0036] A frost-resistant weathered slag solidifying agent, the raw materials of which include: 5 kg steel slag, 2 kg red mud, 20 kg fly ash, 3 kg power plant slag, 5 kg limestone powder, 1 kg shale, 3 kg phosphogypsum, 3 kg titanium gypsum, 1 kg sodium humate, 0.01 kg carbodiimide, 1 kg N-hydroxysuccinimide, 5 kg gelatin, 1 kg chitosan, 1 kg calcium chloride, 1 kg slow-release urea, 0.2 kg sodium sulfate, 0.2 kg urease, 0.1 kg potassium hydroxide, 3 kg sodium silicate, and 1.5 kg calcium lignosulfonate.

[0037] The slow-release urea is prepared using the following specific steps: Heat 2 kg of water to 50°C, add 0.01 kg of polyvinyl alcohol and 0.01 kg of sodium dodecylbenzenesulfonate while stirring, stir for 5 min, add 1 kg of γ-polyglutamic acid, continue stirring for 10 min, adjust the pH of the system to 6-6.4, spray it onto the surface of 5 kg of urea particles with a particle size of 2-4.75 mm, and dry.

[0038] The preparation method of the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0039] S1. Add steel slag, red mud, fly ash, power plant slag, limestone powder, shale, phosphogypsum, and titanium gypsum to a ball mill and ball mill for 30 minutes at a speed of 2000 rpm and a ball-to-material ratio of 3:1 to obtain a specific surface area ≥500 m². 2 / kg of powder;

[0040] S2. Disperse sodium humate in 20 kg of water, add carbodiimide and N-hydroxysuccinimide, stir at 40°C for 5 min, add gelatin and chitosan and continue stirring for 1 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler.

[0041] S3. Add the powder and self-healing reinforcing filler to the mixer, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate, and calcium lignosulfonate. Stir at 100 r / min for 10 min.

[0042] The method of using the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0043] (1) Dry the weathered stone slag until its moisture content is ≤10%;

[0044] (2) Add the above-mentioned frost-resistant weathered stone soil solidifier to the sun-dried weathered stone soil and mix evenly. The mass ratio of the frost-resistant weathered stone soil solidifier to the sun-dried weathered stone soil is 3:100.

[0045] Example 2

[0046] A frost-resistant weathered slag solidifying agent, the raw materials of which include: 25 kg steel slag, 8 kg red mud, 50 kg fly ash, 25 kg power plant slag, 15 kg limestone powder, 5 kg shale, 8 kg phosphogypsum, 8 kg titanium gypsum, 2 kg sodium humate, 0.1 kg carbodiimide, 2 kg N-hydroxysuccinimide, 15 kg gelatin, 2 kg chitosan, 2 kg calcium chloride, 10 kg slow-release urea, 2 kg sodium sulfate, 3 kg urease, 3 kg potassium hydroxide, 10 kg sodium silicate, and 3 kg sodium polyacrylate.

[0047] The slow-release urea is prepared using the following specific steps: Heat 6 kg of water to 60°C, add 0.1 kg of polyvinyl alcohol and 0.1 kg of sodium dodecylbenzene sulfonate while stirring, stir for 15 min, add 2 kg of γ-polyglutamic acid, continue stirring for 20 min, adjust the pH of the system to 6-6.4, spray it onto the surface of 10 kg of urea particles with a particle size of 2-4.75 mm, and dry.

[0048] The preparation method of the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0049] S1. Add steel slag, red mud, fly ash, power plant slag, limestone powder, shale, phosphogypsum, and titanium gypsum to a ball mill and ball mill for 60 minutes at a speed of 4000 rpm and a ball-to-material ratio of 5:1 to obtain a specific surface area ≥500 m². 2 / kg of powder;

[0050] S2. Disperse sodium humate into 30 kg of water, add carbodiimide and N-hydroxysuccinimide, stir at 50°C for 15 min, add gelatin and chitosan and continue stirring for 4 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler.

[0051] S3. Add the powder and self-healing reinforcing filler to the mixer, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate, and sodium polyacrylate. Stir at 500 r / min for 50 min.

[0052] The method of using the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0053] (1) Dry the weathered stone slag until its moisture content is ≤10%;

[0054] (2) Add the above-mentioned frost-resistant weathered stone soil solidifier to the sun-dried weathered stone soil and mix evenly. The mass ratio of the frost-resistant weathered stone soil solidifier to the sun-dried weathered stone soil is 5:100.

[0055] Example 3

[0056] A frost-resistant weathered slag solidifying agent, the raw materials of which include: 10 kg steel slag, 6 kg red mud, 30 kg fly ash, 20 kg power plant slag, 8 kg limestone powder, 4 kg shale, 5 kg reinforcing filler, 6 kg titanium gypsum, 1.3 kg sodium humate, 0.08 kg carbodiimide, 1.3 kg N-hydroxysuccinimide, 12 kg gelatin, 1.4 kg chitosan, 1.7 kg calcium chloride, 2 kg slow-release urea, 0.8 kg sodium sulfate, 1 kg urease, 2 kg potassium hydroxide, 5 kg sodium silicate, and 2.5 kg sodium lignosulfonate.

[0057] The slow-release urea is prepared using the following specific steps: Heat 3 kg of water to 57°C, add 0.02 kg of polyvinyl alcohol and 0.07 kg of sodium dodecylbenzenesulfonate while stirring, stir for 8 min, add 1.8 kg of γ-polyglutamic acid, continue stirring for 13 min, adjust the pH of the system to 6-6.4, spray it onto the surface of 9 kg of urea particles with a particle size of 2-4.75 mm, and dry.

[0058] The reinforcing filler is prepared using the following specific steps: 1 kg of hexadecyltrimethylammonium bromide, 2 kg of sodium dodecyl sulfate, and 2 kg of triethanolamine are added to 100 kg of water and stirred at 60°C for 2 hours. While stirring, 1 kg of amino-terminated polyamide amine and 10 kg of tetraethyl orthosilicate are added and stirred at 500 r / min for 30 minutes. Then, 1 kg of saturated ammonia water is added and stirring is continued for 10-20 hours. The mixture is then filtered, washed, and freeze-dried.

[0059] The preparation method of the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0060] S1. Steel slag, red mud, fly ash, power plant slag, limestone powder, shale, reinforcing filler, and titanium gypsum are added to a ball mill and ball-milled for 40 minutes at a speed of 3500 rpm and a ball-to-material ratio of 3.5:1, to obtain a specific surface area ≥600 m². 2 / kg of powder;

[0061] S2. Disperse sodium humate into 22 kg of water, add carbodiimide and N-hydroxysuccinimide, stir at 48°C for 8 min, add gelatin and chitosan and continue stirring for 3 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler.

[0062] S3. Add the powder and self-healing reinforcing filler to the mixer, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate, and sodium lignosulfonate. Stir at 200 r / min for 40 min.

[0063] The method of using the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0064] (1) Dry the weathered stone slag until its moisture content is ≤10%;

[0065] (2) Add the above-mentioned frost-resistant weathered stone soil solidifier to the sun-dried weathered stone soil and mix evenly. The mass ratio of the frost-resistant weathered stone soil solidifier to the sun-dried weathered stone soil is 8:100.

[0066] Example 4

[0067] A frost-resistant weathered slag solidifying agent, the raw materials of which include: 20 kg steel slag, 4 kg red mud, 40 kg fly ash, 10 kg power plant slag, 12 kg limestone powder, 2 kg shale, 6 kg reinforcing filler, 4 kg titanium gypsum, 1.7 kg sodium humate, 0.02 kg carbodiimide, 1.7 kg N-hydroxysuccinimide, 8 kg gelatin, 1.8 kg chitosan, 1.3 kg calcium chloride, 8 kg slow-release urea, 0.4 kg sodium sulfate, 2 kg urease, 1 kg potassium hydroxide, 7 kg sodium silicate, and 2 kg sodium dodecyl sulfonate.

[0068] The slow-release urea is prepared using the following specific steps: Heat 5 kg of water to 53°C, add 0.08 kg of polyvinyl alcohol and 0.03 kg of sodium dodecylbenzenesulfonate while stirring, stir for 12 min, add 1.2 kg of γ-polyglutamic acid, continue stirring for 17 min, adjust the pH of the system to 6-6.4, spray it onto the surface of 7 kg of urea particles with a particle size of 2-4.75 mm, and dry.

[0069] The reinforcing filler is prepared using the following specific steps: 2 kg of hexadecyltrimethylammonium bromide, 1 kg of sodium dodecyl sulfate, and 6 kg of triethanolamine are added to 50 kg of water and stirred at 70°C for 1 hour. While stirring, 5 kg of amino-terminated polyamide amine and 5 kg of tetraethyl orthosilicate are added and stirred at 1000 r / min for 10 minutes. Then, 5 kg of saturated ammonia water is added and stirring is continued for 10-20 hours. The mixture is then filtered, washed, and freeze-dried.

[0070] The preparation method of the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0071] S1. Steel slag, red mud, fly ash, power plant slag, limestone powder, shale, reinforcing filler, and titanium gypsum are added to a ball mill and ball-milled for 50 minutes at a speed of 2500 rpm and a ball-to-material ratio of 4.5:1, to obtain a specific surface area ≥600 m². 2 / kg of powder;

[0072] S2. Disperse sodium humate in 28 kg of water, add carbodiimide and N-hydroxysuccinimide, stir at 42°C for 12 min, add gelatin and chitosan and continue stirring for 2 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler.

[0073] S3. Add the powder and self-healing reinforcing filler to the mixer, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate, and sodium dodecyl sulfonate. Stir at 400 r / min for 20 min.

[0074] The method of using the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0075] (1) Dry the weathered stone slag until its moisture content is ≤10%;

[0076] (2) The above-mentioned frost-resistant weathered stone soil solidifier is added to the sun-dried weathered stone soil and mixed evenly. The mass ratio of the frost-resistant weathered stone soil solidifier to the sun-dried weathered stone soil is 10:100.

[0077] Example 5

[0078] A frost-resistant weathered slag solidifying agent, the raw materials of which include: 15 kg steel slag, 5 kg red mud, 35 kg fly ash, 15 kg power plant slag, 10 kg limestone powder, 3 kg shale, 5.5 kg reinforcing filler, 5 kg titanium gypsum, 1.5 kg sodium humate, 0.05 kg carbodiimide, 1.5 kg N-hydroxysuccinimide, 10 kg gelatin, 1.6 kg chitosan, 1.5 kg calcium chloride, 5 kg slow-release urea, 0.6 kg sodium sulfate, 1.5 kg urease, 1.5 kg potassium hydroxide, 6 kg sodium silicate, and 2.2 kg sodium dodecyl sulfonate.

[0079] The slow-release urea is prepared using the following specific steps: Heat 4 kg of water to 55°C, add 0.05 kg of polyvinyl alcohol and 0.05 kg of sodium dodecylbenzene sulfonate while stirring, stir for 10 min, add 1.5 kg of γ-polyglutamic acid, continue stirring for 15 min, adjust the pH of the system to 6-6.4, spray it onto the surface of 8 kg of urea particles with a particle size of 2-4.75 mm, and dry.

[0080] The reinforcing filler is prepared using the following specific steps: 1.5 kg of hexadecyltrimethylammonium bromide, 1.5 kg of sodium dodecyl sulfate, and 4 kg of triethanolamine are added to 80 kg of water and stirred at 65°C for 1.5 h. While stirring, 3 kg of amino-terminated polyamide amine and 8 kg of tetraethyl orthosilicate are added and stirred at 800 r / min for 20 min. Then, 3 kg of saturated ammonia water is added and stirring is continued for 15 h. The mixture is then filtered, washed, and freeze-dried.

[0081] The preparation method of the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0082] S1. Steel slag, red mud, fly ash, power plant slag, limestone powder, shale, reinforcing filler, and titanium gypsum are added to a ball mill and ball-milled for 45 minutes at a speed of 3000 rpm and a ball-to-material ratio of 4:1, to obtain a specific surface area ≥600 m². 2 / kg of powder;

[0083] S2. Disperse sodium humate in 25 kg of water, add carbodiimide and N-hydroxysuccinimide, stir at 45°C for 10 min, add gelatin and chitosan and continue stirring for 2.5 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler;

[0084] S3. Add the powder and self-healing reinforcing filler to the mixer, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate, and sodium dodecyl sulfonate. Stir at 300 r / min for 30 min.

[0085] The method of using the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0086] (1) Dry the weathered stone slag until its moisture content is ≤10%;

[0087] (2) The above-mentioned antifreeze weathered stone soil solidifier is added to the sun-dried weathered stone soil and mixed evenly. The mass ratio of the antifreeze weathered stone soil solidifier to the sun-dried weathered stone soil is 12:100.

[0088] Comparative Example 1

[0089] Soil stabilizer was purchased from Shandong Mouya New Materials Co., Ltd.

[0090] Comparative Example 2

[0091] A frost-resistant weathered stone slag soil solidifying agent, the raw materials of which include: 15 kg steel slag, 5 kg red mud, 35 kg fly ash, 15 kg power plant slag, 10 kg limestone powder, 3 kg shale, 5.5 kg reinforcing filler, 5 kg titanium gypsum, 10 kg gelatin, 1.5 kg calcium chloride, 5 kg slow-release urea, 0.6 kg sodium sulfate, 1.5 kg urease, 1.5 kg potassium hydroxide, 6 kg sodium silicate, and 2.2 kg sodium dodecyl sulfate.

[0092] The slow-release urea is prepared using the following specific steps: Heat 4 kg of water to 55°C, add 0.05 kg of polyvinyl alcohol and 0.05 kg of sodium dodecylbenzene sulfonate while stirring, stir for 10 min, add 1.5 kg of γ-polyglutamic acid, continue stirring for 15 min, adjust the pH of the system to 6-6.4, spray it onto the surface of 8 kg of urea particles with a particle size of 2-4.75 mm, and dry.

[0093] The reinforcing filler is prepared using the following specific steps: 1.5 kg of hexadecyltrimethylammonium bromide, 1.5 kg of sodium dodecyl sulfate, and 4 kg of triethanolamine are added to 80 kg of water and stirred at 65°C for 1.5 h. While stirring, 3 kg of amino-terminated polyamide amine and 8 kg of tetraethyl orthosilicate are added and stirred at 800 r / min for 20 min. Then, 3 kg of saturated ammonia water is added and stirring is continued for 15 h. The mixture is then filtered, washed, and freeze-dried.

[0094] The preparation method of the above-mentioned frost-resistant weathered rock slag solidifier includes the following steps:

[0095] S1. Steel slag, red mud, fly ash, power plant slag, limestone powder, shale, reinforcing filler, and titanium gypsum are added to a ball mill and ball-milled for 45 minutes at a speed of 3000 rpm and a ball-to-material ratio of 4:1, to obtain a specific surface area ≥600 m². 2 / kg of powder;

[0096] S2. Add the powder and gelatin to the mixer, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate, and sodium dodecyl sulfonate. Stir at 300 r / min for 30 min.

[0097] The above-mentioned method for using the soil-cement solidifying agent for frost-resistant weathered rock slag includes the following steps:

[0098] (1) Dry the weathered stone slag until its moisture content is ≤10%;

[0099] (2) The above-mentioned antifreeze weathered stone slag soil solidifier is added to the sun-dried weathered stone slag soil and mixed evenly. The mass ratio of the antifreeze weathered stone slag soil solidifier to the sun-dried weathered stone slag soil is 12:100.

[0100] According to the instructions for the soil stabilizer used in Comparative Example 1, it was mixed with weathered rock slag to prepare stabilized soil. This stabilized soil was then molded along with the stabilized soils obtained in Example 5 and Comparative Example 2, and demolded after 1 day. Referring to CJJT 286-2018 "Technical Standard for Application of Soil Stabilizers", each group of samples was sealed and cured under standard conditions, and completely immersed in a water tank for 24 hours the day before testing. The unconfined compressive strength of each group of samples was then tested at 7 days and 28 days.

[0101] like Figure 1 As shown, the solidified soil obtained in Example 5 and Comparative Example 2 is significantly better than the solidified soil obtained using the soil stabilizer used in Comparative Example 1 (P < 0.01), and the solidified soil obtained in Example 5 is better than that in Comparative Example 2 (P < 0.05).

[0102] A load of 200 kN was applied to the solidified soil obtained above, and the displacement of each group of samples was measured. Figure 2 As shown, the solidified soil obtained in Example 5 exhibited the largest displacement under pressure, indicating that it possessed the best toughness. This invention utilizes a self-healing reinforcing filler that acts as a spring, resulting in increased deformation and enhanced toughness of the solidified soil specimen under the same load.

[0103] Referring to GB / T 50082-2009 "Standard for Test Methods of Long-Term Performance and Durability of Ordinary Concrete", the slow freezing method was used to conduct freeze-thaw cycle tests on the above-mentioned groups of solidified soil. The specimen mass was recorded at 0, 25, 50, 75, 100, 125, 150, 175, and 200 freeze-thaw cycles, respectively. If the weight loss rate exceeded 5%, the test for that group was stopped.

[0104] like Figure 3 As shown, the solidified soil obtained in Comparative Example 1 had a mass loss rate exceeding 5% after 175 cycles, and the test was stopped. In contrast, the solidified soil obtained in Example 5 had the lowest mass loss rate at each cycle number.

[0105] In summary, the soil-cementing solidifier obtained in this invention can effectively improve the compressive strength and toughness of weathered stone waste soil, and enhance its resistance to freeze-thaw cycles and frost cracking. This is because this invention grafts sodium humate onto gelatin and then combines it with powder. Not only is the dispersion uniformity excellent, but the calcium ion cross-linking forms a well-developed and stable cross-linked network in the system. This network not only absorbs free water from the weathered stone waste soil and exhibits good plasticity, but the resulting cementing components effectively bind the weathered stone waste soil, significantly enhancing its resistance to erosion and freeze-thaw cycles, and making it easier to compact. Furthermore, the gel of this invention effectively fills the pores between weathered stone waste soil particles and, after hardening, effectively overcomes volume shrinkage. Even when surface cracks appear, under certain wet-dry cycles, the reversibility of the coordination bonds between sodium humate, chitosan, and calcium ions, along with their absorption and expansion properties, promotes crack reduction, demonstrating strong self-healing capabilities and effectively ensuring the soil's resistance to freeze-thaw cracking.

[0106] Meanwhile, when cracks appear in the solidified soil system, the slow-release urea used in this invention can slowly release urea and, in combination with urease, decompose the slow-release urea to form carbonate ions. Under the action of calcium ions in the system, calcium carbonate precipitate can be formed and further fill the cracks. Combined with the self-healing reinforcing filler, the self-healing effect of the system is extremely excellent, with good durability and impermeability, effectively ensuring the soil's resistance to frost cracking.

[0107] This invention further utilizes a compound of hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, and triethanolamine to form micelles. This promotes the deposition of well-ordered nanoparticles of nano-silica on the surface of macromolecular-terminated amino polyamide amine structures. This results in a product with an ultra-high specific surface area and self-healing reinforcing filler, leading to better solidification of weathered stone slag and allowing for better penetration into the system structure to form dendritic branches, effectively enhancing the product's resistance to frost cracking. Furthermore, the reinforcing filler contains a large number of positively charged amino groups, which, under the action of potassium hydroxide, can electrostatically adsorb with the self-healing reinforcing filler, further improving the solidification effect. This, combined with the calcium carbonate deposition during the solidification process, effectively fills the pores in the system, resulting in excellent frost crack resistance in the product.

[0108] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A frost-resistant weathered rock slag solidifying agent, characterized in that, The raw materials, by weight, include: 5-25 parts steel slag, 2-8 parts red mud, 20-50 parts fly ash, 3-25 parts power plant slag, 5-15 parts limestone powder, 1-5 parts shale, 3-8 parts reinforcing filler, 3-8 parts titanium gypsum, 1-2 parts sodium humate, 0.01-0.1 parts carbodiimide, 1-2 parts N-hydroxysuccinimide, 5-15 parts gelatin, 1-2 parts chitosan, 1-2 parts calcium chloride, 1-10 parts slow-release urea, 0.2-2 parts sodium sulfate, 0.2-3 parts urease, 0.1-3 parts potassium hydroxide, 3-10 parts sodium silicate, and 1.5-3 parts dispersant. The reinforcing filler is prepared using the following specific steps: hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, and triethanolamine are added to water and stirred at 60-70℃ for 1-2 hours. While stirring, amino-terminated polyamide amine and tetraethyl orthosilicate are added, followed by saturated ammonia water and stirring for another 10-20 hours. The mixture is then filtered, washed, and freeze-dried. The following steps are used to prepare it: S1. Steel slag, red mud, fly ash, power plant slag, limestone powder, shale, reinforcing filler, and titanium gypsum are ball-milled to obtain powder. S2. Disperse sodium humate in water, add carbodiimide and N-hydroxysuccinimide, stir at 40-50℃ for 5-15 min, add gelatin and chitosan and continue stirring for 1-4 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler; S3. Mix the powder and self-healing reinforcing filler, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate and dispersant and stir evenly.

2. The frost-resistant weathered rock slag solidifying agent according to claim 1, characterized in that, The slow-release urea is prepared using the following specific steps: heat water to 50-60℃, add polyvinyl alcohol and sodium dodecylbenzenesulfonate while stirring, stir for 5-15 minutes, add γ-polyglutamic acid and continue stirring for 10-20 minutes, adjust the pH of the system to 6-6.4, spray it onto the surface of urea particles, and dry.

3. The frost-resistant weathered rock slag solidifying agent according to claim 1, characterized in that, The dispersant is at least one of lignosulfonate, dodecyl sulfonate, and polyacrylate.

4. A method for preparing a soil-cementing agent for frost-resistant weathered rock slag as described in any one of claims 1-3, characterized in that, Includes the following steps: S1. Steel slag, red mud, fly ash, power plant slag, limestone powder, shale, reinforcing filler, and titanium gypsum are ball-milled to obtain powder. S2. Disperse sodium humate in water, add carbodiimide and N-hydroxysuccinimide, stir at 40-50℃ for 5-15 min, add gelatin and chitosan and continue stirring for 1-4 h, centrifuge, wash, freeze dry to obtain self-healing reinforced filler; S3. Mix the powder and self-healing reinforcing filler, and add calcium chloride, slow-release urea, sodium sulfate, urease, potassium hydroxide, sodium silicate and dispersant and stir evenly.

5. The preparation method of the frost-resistant weathered rock slag solidifying agent according to claim 4, characterized in that, In S1, the ball mill speed is 2000-4000 rpm, the ball milling time is 30-60 min, and the ball-to-material ratio is 3-5:

1.

6. The preparation method of the frost-resistant weathered rock slag solidifying agent according to claim 4, characterized in that, In S1, the specific surface area of ​​the powder is 500-600 m². 2 / kg.

7. The preparation method of the frost-resistant weathered rock slag solidifying agent according to claim 4, characterized in that, In S2, the mass ratio of sodium humate to water is 1-2:20-30.

8. A method for using the frost-resistant weathered rock slag solidifying agent as described in any one of claims 1-3, characterized in that, Includes the following steps: (1) Dry the weathered stone slag; (2) The frost-resistant weathered stone slag solidifier according to any one of claims 1-3 is added to the sun-dried weathered stone slag and mixed evenly, wherein the mass ratio of the frost-resistant weathered stone slag solidifier to the sun-dried weathered stone slag is 3-12:

100.

9. The method of using the antifreeze weathered rock slag solidifying agent according to claim 8, characterized in that, In step (1), the weathered stone slag is dried until its moisture content is ≤10%.

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