Single-component soil stabilizer as well as preparation method and application thereof

Abstract

The invention provides a single-component soil stabilizer as well as a preparation method and application thereof. The single-component soil stabilizer is prepared from the following raw materials: modified aluminum silicate salt, cement, an alkaline activator, an ion exchanger, a flocculant, an accelerator, salt-tolerant quaternary ammonium salt, a calcium aluminate complex, an early strength agent and nano silicon dioxide. The modified aluminum silicate salt is aluminum silicate salt modified by a silane coupling agent. Through molecular structure design and functional group optimization, a single-component material with efficient excitation, ion exchange, cementation filling and hydrophobic corrosion resistance functions is developed.

Description

Technical Field

[0001] This invention relates to the field of soil stabilization, specifically to a single-component soil stabilizing agent, its preparation method, and its application. Background Technology

[0002] South my country has a hot and humid climate with abundant rainfall, and is home to a wide variety of unique soils, including soft soils with high water content, red clay, and marine sedimentary soils. These soils generally exhibit low strength, high compressibility, and poor water stability, severely hindering transportation infrastructure, water conservancy projects, and urban development. Traditional foundation treatment technologies (such as replacement and pile foundations) suffer from high costs, long cycles, and high energy consumption. Existing soil stabilizers often rely on multi-component formulations (such as cement + lime + chemical additives), which have drawbacks such as complex proportions, poor construction controllability, and insufficient adaptability. In particular, their stabilization effect is unstable in the high-organic-content and highly saline soils of South China.

[0003] To address the above problems, this invention is proposed. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a single-component soil stabilizer, its preparation method and application, and through molecular structure design and functional group optimization, develops a single-component material with efficient activation, ion exchange, cementation and filling and hydrophobic anti-corrosion functions.

[0005] According to a first aspect of the present invention, a single-component soil stabilizer is provided, comprising the following raw materials: modified aluminum silicate, cement, alkaline activator, ion exchanger, flocculant, quick-setting agent, salt-tolerant quaternary ammonium salt, calcium aluminate complex, early-strength agent, and nano-silica; wherein the modified aluminum silicate is an aluminum silicate modified with a silane coupling agent.

[0006] In the single-component soil stabilizer proposed in this invention, the salt-tolerant quaternary ammonium salt can effectively increase the hydrophobic chain density and improve the strength retention rate after salt cycling; the calcium aluminate complex has an early strength activating group, which can effectively improve the strength after 7 days; and the chelating group formed by nano-silica can effectively reduce the water immersion disintegration rate.

[0007] In some preferred embodiments, the silane coupling agent is at least one of γ-aminopropyltriethoxysilane (KH-550) or γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH-560). The silane coupling agent has a molecular structure where one end is a siloxane group capable of reacting with hydroxyl groups (-OH) on the surface of inorganic materials, and the other end is an amino group (KH-550) or an epoxy group (KH-560) capable of binding with organic matter or certain components in the soil. It forms a monolayer on the surface of aluminosilicate salt particles, acting as a "molecular bridge" and significantly enhancing the chemical bonding and mechanical properties of the curing agent with the soil system. Modification can be achieved by spraying, where the silane coupling agent solution or dilution is atomized through a nozzle and sprayed onto the aluminosilicate salt powder in a suspended or fluidized state (such as a fluidized bed), while simultaneously being heated and dried. Silane coupling agent-modified aluminum silicate salts have adhesive properties and stable chemical properties, making them suitable for application in various soils without causing adverse pollution.

[0008] In some embodiments, the single-component soil stabilizer comprises the following raw materials by mass percentage: 35%–45% modified aluminum silicate; 25%–30% cement; 6%–8% alkaline activator; 1.5%–3% ion exchanger; 0.15%–0.3% flocculant; 2%–4% quick-setting agent; 1%–2% salt-tolerant quaternary ammonium salt; 5%–8% calcium aluminate complex; 2%–4% early-strength agent; and 15%–20% nano-silica.

[0009] In some embodiments, the cement is selected from ordinary Portland cement PO 42.5; And / or, the quick-setting agent is sodium silicate.

[0010] By properly combining cement with modified aluminum silicate salts and using accelerators, the final strength of the product can be effectively improved, thereby achieving the desired curing effect.

[0011] In some embodiments, the alkaline activator is selected from calcium hydroxide; And / or, the flocculant is selected from PAM.

[0012] PAM flocculant can effectively improve the agglomeration effect of soil, and when combined with alkali-activating components, it can effectively improve the soil solidification efficiency.

[0013] In some embodiments, the ion exchanger is selected from anhydrous aluminum sulfate; And / or, the early strength agent is selected from calcium formate.

[0014] Thanks to the effects of ion exchangers and the use of early-strength agents, the early-stage activation strength of curing agents can be effectively improved, resulting in rapid solidification.

[0015] In some embodiments, the calcium aluminate complex comprises UEA calcium thioaluminate; And / or, the salt-resistant quaternary ammonium salt includes chitosan quaternary ammonium salt.

[0016] The consolidation problem of saline-alkali soils can be effectively solved by adding quaternary ammonium salts and utilizing their cation-capturing ability.

[0017] According to a second aspect of the present invention, a method for preparing a single-component soil stabilizer as described in the first aspect is provided, comprising the following steps: The raw materials are mixed evenly according to the formula to obtain the single-component soil stabilizer.

[0018] According to a third aspect of the present invention, the application of a single-component soil stabilizer prepared by the preparation method described in the first aspect of the present invention or the second aspect of the present invention in soil stabilization is proposed.

[0019] In some embodiments, the single-component soil stabilizer is added to the soil at a concentration of 1.2% to 3.0%.

[0020] In some preferred embodiments, the admixture content for coastal saline soil is 1.2% to 2.0%; And / or, for red clay, the admixture amount is 0.8%~1.0%; And / or, for high-organic soft soils, the admixture amount is 2.0% to 3.0%.

[0021] According to one embodiment of the present invention, at least the following beneficial effects are achieved: 1. This invention breaks through the bottleneck of low on-site mixing accuracy and weak reaction synergy of multi-component curing agents, significantly improving construction convenience and quality controllability; at the same time, it can address the core problems of weak water dispersibility and poor salt corrosion stability by synergistic effects of ion exchange, cementation curing and hydrophobic modification, targeting the characteristics of soils in South China (such as the mineral composition dominated by kaolinite and the high chloride ion environment), thereby achieving rapid strengthening and long-term durability of soft soils.

[0022] 2. Existing common early-strength activating components are mostly single silicate-calcium vanadate systems, which are susceptible to salt corrosion and have significant pH limitations. Compared with composite aluminosilicate systems, they cannot simultaneously achieve early-strength activation, resistance to water dispersion, and resistance to salt corrosion. This invention solves the aforementioned technical contradictions of single-component systems by constructing an "organic-inorganic hybrid" single-component molecular model, integrating activators (such as aluminosilicate activating groups), stabilizers (salt-resistant ion groups), and hydrophobic segments.

[0023] 3. This invention provides a low-cost, low-environmental-impact solution for highway subgrade, riverbank protection, and coastal mudflat projects in South China. It is of great strategic significance for alleviating the shortage of sand and gravel resources, reducing carbon emissions, and ensuring the safety of major infrastructure, and promotes the upgrading of soil solidification technology towards green and efficient development. Detailed Implementation

[0024] The following will describe the concept and technical effects of the present invention clearly and completely with reference to the embodiments, so as to fully understand the purpose, features and effects of the present invention.

[0025] Unless otherwise specified, the raw materials, reagents, or apparatus used in the following examples are all available from conventional commercial sources or can be obtained by existing known methods. PAM was purchased from Foshan Lide Coating New Materials Co., Ltd.; the modified aluminosilicate was obtained by spray-treating the aluminosilicate with γ-aminopropyltriethoxysilane.

[0026] Example 1 This embodiment provides a single-component soil stabilizer, which is prepared by uniformly mixing the following raw materials in the indicated mass percentages: 35% modified aluminum silicate; 30% PO 42.5 cement; 5% calcium hydroxide; 2% anhydrous aluminum sulfate; 0.15% PAM; 2.25% sodium silicate; 1.6% chitosan quaternary ammonium salt; 7% UEA calcium sulfoaluminate; 2% calcium formate; and 15% nano-silica.

[0027] Example 2 The difference from Example 1 is that the content of modified aluminum silicate is 45% and the content of PAM is 0.3%.

[0028] Comparative Example 1 The difference from Example 1 is that the modified aluminum silicate is replaced with an equal amount of potassium silicate.

[0029] Comparative Example 2 The difference from Example 1 is that the modified aluminum silicate salt is replaced with an equal amount of microsilica powder.

[0030] Comparative Example 3 The difference from Example 2 is that the modified aluminum silicate is replaced with an equal amount of potassium silicate.

[0031] Comparative Example 4 The difference from Example 2 is that the modified aluminum silicate salt is replaced with an equal amount of microsilica powder.

[0032] Comparative Example 5 The difference from Example 1 is that PAM is replaced with an equal amount of aluminum sulfate.

[0033] Comparative Example 6 The difference from Example 2 is that PAM is replaced with an equal amount of aluminum sulfate.

[0034] Test case Coastal saline soil from the Pearl River Delta region was collected and mixed with single-component soil stabilizers from Examples 1-2 and Comparative Examples 1-6 at a dosage of 2%, as well as commercially available similar products (purchased from Leizhikezhijie). Mechanical properties, water stability, salt resistance, and environmental adaptability were tested, and the results are shown in Table 1 below. Flocculation tests were also conducted on the single-component soil stabilizers from Examples 1-2 and Comparative Examples 5-6, and the results are shown in Table 2 below. Table 1

[0035] Table 2

[0036] As shown in Table 1, the modified aluminum silicate salt has the best effect on strength retention rate, strength, and water immersion disintegration rate among the three common raw materials. Considering the total amount added and other components, the optimal ratio is 35%-45%.

[0037] As shown in Table 2, PAM performs better than aluminum sulfate at the same dosage. Meanwhile, the amount of aluminum sulfate added has a significant impact on the setting time and results in lower strength. Therefore, a PAM dosage of approximately 0.15%-0.3% is recommended.

[0038] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A single-component soil stabilizer, characterized in that, The preparation materials include the following: modified aluminum silicate, cement, alkaline activator, ion exchanger, flocculant, quick-setting agent, salt-resistant quaternary ammonium salt, calcium aluminate complex, early strength agent and nano silica; the modified aluminum silicate is an aluminum silicate modified with a silane coupling agent.

2. The single-component soil stabilizer according to claim 1, characterized in that, The preparation materials include the following raw materials by mass percentage: 35%–45% modified aluminum silicate; 25%–30% cement; 5%–8% alkaline activator; 1.5%–3% ion exchanger; 0.15%–0.3% flocculant; 2%–4% quick-setting agent; 1%–2% salt-resistant quaternary ammonium salt; 5%–8% calcium aluminate complex; 2%–4% early-strength agent; and 15%–20% nano-silica.

3. The single-component soil stabilizer according to claim 1, characterized in that, The cement is selected from ordinary Portland cement PO 42.5; And / or, the quick-setting agent is selected from sodium silicate.

4. The single-component soil stabilizer according to claim 1, characterized in that, The alkaline activator is selected from calcium hydroxide; And / or, the flocculant is selected from PAM.

5. The single-component soil stabilizer according to claim 1, characterized in that, The ion exchanger is selected from anhydrous aluminum sulfate; And / or, the early strength agent is selected from calcium formate.

6. The single-component soil stabilizer according to claim 1, characterized in that, The calcium aluminate complex is selected from UEA calcium thioaluminate; And / or, the salt-resistant quaternary ammonium salt is selected from chitosan quaternary ammonium salts.

7. A method for preparing a single-component soil stabilizer as described in any one of claims 1-6, characterized in that, Includes the following steps: The raw materials are mixed evenly according to the formula to obtain the single-component soil stabilizer.

8. The application of the single-component soil stabilizer according to any one of claims 1-6 or the single-component soil stabilizer prepared by the preparation method according to claim 7 in soil stabilization.

9. The application according to claim 8, characterized in that, The dosage of the single-component soil stabilizer in the soil is 1.2% to 3.0%.

10. The application according to claim 9, characterized in that, For coastal saline soils, the admixture dosage is 1.2%~2.0%; And / or, for red clay, the admixture amount is 0.8%~1.0%; And / or, for high-organic soft soils, the admixture amount is 2.0% to 3.0%.

Images