High-temperature-resistant fluidized stabilized soil and preparation method thereof

Abstract

The invention relates to the technical field of soil solidification, and provides high-temperature-resistant flow-state solidified soil which comprises muck, a curing agent and a high-temperature-resistant reinforcing agent according to the weight ratio of (4.5-8.5): (0.5-1): (0.5-5). Wherein the high-temperature-resistant reinforcing agent comprises aluminum oxide, sodium silicate and nano titanium dioxide. The invention also provides a preparation method of the high-temperature-resistant fluidized stabilized soil. The high-temperature-resistant fluid-state solidified soil has the advantages that the aluminum oxide, the sodium silicate and the nano titanium dioxide are used as high-temperature-resistant reinforcing agents, the compactness of a matrix is remarkably improved by utilizing the synergistic effect of the aluminum oxide, the sodium silicate and the nano titanium dioxide in the high-temperature-resistant fluid-state solidified soil, and the matrix is endowed with good mechanical properties and excellent high-temperature resistance; on the basis, the solidified soil can still keep good strength and stability in a high-temperature environment, the service life of the solidified soil in a high-temperature area is ensured, and the solidified soil has important practical application value.

Description

Technical Field

[0001] The present invention relates to the technical field of soil solidification, and particularly to a high-temperature resistant fluidized solidified soil and a preparation method thereof. Background Art

[0002] With the acceleration of the urbanization process, soil solidification technology has been widely used in infrastructure construction. Traditional soil solidifying agents are usually composed of materials such as cement, lime, and fly ash, which can effectively improve the strength and stability of soil. However, in a high-temperature environment, the performance of traditional solidifying agents often decreases significantly, resulting in insufficient strength and durability of the solidified soil and affecting the engineering quality. Therefore, it is of great practical significance to develop a fluidized solidified soil that can maintain good performance in a high-temperature environment.

[0003] At present, some studies have tried to improve the high-temperature resistance of solidified soil by adding high-temperature resistant materials or improving the formula of the solidifying agent, but the effects of these methods are limited and it is difficult to be popularized and applied in actual projects. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a high-temperature resistant fluidized solidified soil with excellent high-temperature resistance and a preparation method thereof.

[0005] The present invention adopts the following technical solutions to solve the above technical problems:

[0006] A high-temperature resistant fluidized solidified soil, comprising muck, a solidifying agent, and a high-temperature resistant reinforcing agent, with weight ratios of (4.5 - 8.5) : (0.5 - 1) : (0.5 - 5); wherein, the high-temperature resistant reinforcing agent includes alumina, sodium silicate, and nano-titanium dioxide.

[0007] As one of the preferred embodiments of the present invention, the solidifying agent includes cement, lime, and fly ash, with weight ratios of 2 : 1 : 2.

[0008] As one of the preferred embodiments of the present invention, in the solidifying agent, the cement is Portland cement with a specific surface area ≥ 300 m 2 / kg; the lime is quicklime with a specific surface area ≥ 400 m 2 / kg; the fly ash is class II fly ash with a specific surface area ≥ 600 m 2 / kg.

[0009] As one of the preferred embodiments of the present invention, in the high-temperature resistant reinforcing agent, the purity of alumina ≥ 99%, the purity of sodium silicate ≥ 99%, the particle size of nano-titanium dioxide is 10 - 100 nm, and the purity ≥ 99%.

[0010] As one of the preferred embodiments of the present invention, in the high-temperature resistant reinforcing agent, the weight ratios of alumina, sodium silicate, and nano-titanium dioxide are 4 : 4 : 1 respectively.

[0011] As one of the preferred embodiments of the present invention, it further includes a water reducing agent and water.

[0012] As one of the preferred embodiments of the present invention, the dosage of the water reducing agent is 0.5% of the weight ratio of the muck, and the water dosage is 30% of the weight ratio of the muck.

[0013] As one of the preferred embodiments of the present invention, the water reducing agent is a polycarboxylate superplasticizer.

[0014] As one of the preferred embodiments of the present invention, the water is tap water.

[0015] A preparation method of the above-mentioned high-temperature resistant fluidized solidified soil includes the following steps:

[0016] (1) Mix the muck, solidifying agent, and high-temperature resistant reinforcing agent evenly to form a mixture.

[0017] (2) Add water and a water reducing agent to the mixture and stir evenly to form a fluidized solidified soil slurry.

[0018] (3) Pour the fluidized solidified soil slurry into a mold for shaping.

[0019] (4) Cure the solidified soil after shaping until the specified age.

[0020] The advantages of the present invention compared with the prior art are as follows:

[0021] The high-temperature resistant fluidized solidified soil of the present invention uses alumina, sodium silicate, and nano-titanium dioxide as high-temperature resistant reinforcing agents. By utilizing their synergistic effects in the high-temperature resistant fluidized solidified soil, the matrix density is significantly improved, endowing it with good mechanical properties and excellent high-temperature resistance. Among them, alumina has excellent high-temperature resistance and mechanical strength, which can effectively improve the heat resistance and compressive strength of the material; in addition, alumina particles can fill between soil particles, reducing the porosity and further improving the compactness and strength of the material; moreover, the chemical stability of alumina makes it not prone to chemical reactions in high-temperature environments, thus maintaining the structural integrity of the material. Sodium silicate will hydrolyze in water to generate silica gel, which can fill the voids between soil particles and play a cementing role, thereby improving the overall strength of the material. Sodium silicate can react with alumina to form a more complex aluminosilicate structure, further enhancing the high-temperature resistance of the material. Due to its nano-size, titanium dioxide has a large specific surface area, which can significantly improve the reaction activity and strength of the material and provide a reaction site for the reaction between alumina and sodium silicate.

[0022] Based on the good mechanical properties and excellent high-temperature resistance of the high-temperature resistant fluid-solidified soil of the present invention, the construction waste, curing agent and high-temperature resistant enhancer are closely packed and evenly distributed, ensuring the service performance of the high-temperature resistant fluid-solidified soil in a high-temperature environment, providing guarantee for the service life of building structures in high-temperature regions, and having important practical application value. Detailed Embodiment

[0023] The embodiments of the present invention will be described in detail below. These embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation manners and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments. At the same time, the raw materials used in the present invention, unless otherwise specified, are all conventional raw material reagents in the art. The experimental conditions and experimental methods used in the present invention, unless otherwise specified, are all conventional conditions and methods in the art, and will not be elaborated here.

[0024] Example 1

[0025] A kind of high-temperature resistant fluid-solidified soil in this embodiment includes construction waste, curing agent, high-temperature resistant enhancer, water reducing agent and water. Among them, the weight ratios of construction waste, curing agent and high-temperature resistant enhancer are 8.5:1:0.5 respectively, the dosage of the water reducing agent is 0.5% of the weight ratio of the construction waste, and the water dosage is 30% of the weight ratio of the construction waste.

[0026] At the same time, in this embodiment, the high-temperature resistant enhancer includes alumina (purity ≥ 99%), sodium silicate (purity ≥ 99%) and nano-titanium dioxide (particle size 10 - 100nm, purity ≥ 99%), and the weight ratios are 4:4:1 respectively.

[0027] The curing agent includes portland cement (specific surface area ≥ 300m 2 / kg), quicklime (specific surface area ≥ 400m 2 / kg) and fly ash (secondary fly ash, specific surface area ≥ 600m 2 / kg), and the weight ratios are 2:1:2 respectively.

[0028] The construction waste is used as construction engineering waste.

[0029] The water reducing agent uses polycarboxylate superplasticizer

[0030] The water uses tap water.

[0031] Preparation method:

[0032] (1) Use a magnetic stirrer to stir portland cement, quicklime and fly ash into a uniform curing agent, and stir alumina, sodium silicate and nano-titanium dioxide into a uniform high-temperature resistant enhancer.

[0033] (2) Weigh construction waste, curing agent, high-temperature resistant enhancer, water reducing agent and water according to the above ratios.

[0034] (3) Mix the muck, curing agent, and high-temperature resistant strengthening agent evenly to form a mixture.

[0035] (4) Add water and water reducer to the mixture and stir evenly to form a fluidized solidified soil slurry.

[0036] (5) Pour the fluidized solidified soil slurry into a mold for shaping.

[0037] (6) Cure the solidified soil after shaping until the specified age.

[0038] Example 2

[0039] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main difference is that the weight ratios of muck, curing agent, and high-temperature resistant strengthening agent are 8.05:0.95:1 respectively.

[0040] The preparation method is the same as that in Example 1.

[0041] Example 3

[0042] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main difference is that the weight ratios of muck, curing agent, and high-temperature resistant strengthening agent are 7.6:0.9:1.5 respectively.

[0043] The preparation method is the same as that in Example 1.

[0044] Example 4

[0045] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main difference is that the weight ratios of muck, curing agent, and high-temperature resistant strengthening agent are 7.15:0.85:5 respectively.

[0046] The preparation method is the same as that in Example 1.

[0047] Example 5

[0048] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main difference is that the weight ratios of muck, curing agent, and high-temperature resistant strengthening agent are 6.7:0.8:2.5 respectively.

[0049] The preparation method is the same as that in Example 1.

[0050] Example 6

[0051] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main difference is that the weight ratios of muck, curing agent, and high-temperature resistant strengthening agent are 6.25:0.75:3 respectively.

[0052] The preparation method is the same as that in Example 1.

[0053] Example 7

[0054] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main differences are as follows: the weight ratios of muck, curing agent, and high-temperature resistant enhancer are 5.8:0.7:3.5 respectively.

[0055] The preparation method is the same as that in Example 1.

[0056] Example 8

[0057] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main differences are as follows: the weight ratios of muck, curing agent, and high-temperature resistant enhancer are 5.35:0.65:4 respectively.

[0058] The preparation method is the same as that in Example 1.

[0059] Example 9

[0060] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main differences are as follows: the weight ratios of muck, curing agent, and high-temperature resistant enhancer are 4.9:0.6:4.5 respectively.

[0061] The preparation method is the same as that in Example 1.

[0062] Example 10

[0063] A kind of high-temperature resistant fluidized solidified soil in this example is basically the same as that in Example 1. The main differences are as follows: the weight ratios of muck, curing agent, and high-temperature resistant enhancer are 4.5:0.5:5 respectively.

[0064] The preparation method is the same as that in Example 1.

[0065] Comparative Example 1

[0066] A kind of high-temperature resistant fluidized solidified soil in this comparative example is basically the same as that in Example 1. The main differences are as follows: no high-temperature resistant enhancer (aluminum oxide, sodium silicate, nano-titanium dioxide) is added.

[0067] The preparation method is the same as that in Example 1.

[0068] Comparative Example 2

[0069] A kind of high-temperature resistant fluidized solidified soil in this comparative example is basically the same as that in Example 1. The main differences are as follows: no aluminum oxide is added.

[0070] Comparative Example 3

[0071] A kind of high-temperature resistant fluidized solidified soil in this comparative example is basically the same as that in Example 1. The main differences are as follows: no sodium silicate is added.

[0072] Comparative Example 4

[0073] A high-temperature resistant fluidized solidified soil of this comparative example is basically the same as that of Example 1, and the main difference is that: nano-titanium dioxide is not added.

[0074] Experimental Example 1

[0075] This experimental example is used to verify the application advantages of the high-temperature resistant fluidized solidified soil of the present invention.

[0076] The high-temperature resistant fluidized solidified soil prepared in Examples 1 to 10 and Comparative Examples 1 to 4 of the present invention was subjected to a compressive strength test, and the test method was in accordance with the "Code for Mix Proportion Design of Cement Soil" JGJ / T 233-2011.

[0077] Table 1 shows the test results of the compressive strength of the high-temperature resistant fluidized solidified soil in Examples 1 to 10 and Comparative Examples 1 to 4 of the present invention after curing at different temperatures.

[0078] Table 1 Test results of the compressive strength of the solidified soil in each example and comparative example

[0079]

[0080] It can be seen from the above results that:

[0081] (1) The high-temperature resistant fluidized solidified soil prepared by the present invention effectively improves its high-temperature resistance on the premise of improving its basic strength.

[0082] (2) Compared with Examples 1-10, in Comparative Example 1 (aluminum oxide, sodium silicate and nano-titanium dioxide were not added to the raw materials), the high-temperature resistance of the fluid-solidified soil decreased significantly, indicating that the coupling effect of aluminum oxide, sodium silicate and nano-titanium dioxide can greatly improve the high-temperature resistance of the fluid-solidified soil. Further, combining the results of Comparative Examples 2-4, aluminum oxide has excellent high-temperature resistance and mechanical strength, and can effectively improve the heat resistance and compressive strength of the material. In addition, aluminum oxide particles can be filled between soil particles to reduce the porosity, further improving the compactness and strength of the material. Moreover, the chemical stability of aluminum oxide makes it not prone to chemical reactions in high-temperature environments, thus maintaining the structural integrity of the material. Sodium silicate will hydrolyze in water to form silicic acid gel, which can fill the gaps between soil particles and play a cementing role, thereby improving the overall strength of the material. Sodium silicate can react with aluminum oxide to form a more complex aluminosilicate structure, further enhancing the high-temperature resistance of the material. Due to its nano-size, titanium dioxide has a large specific surface area, which can significantly improve the reaction activity and strength of the material, providing a reaction site for the reaction of aluminum oxide and sodium silicate. Considering the characteristics of these three materials (none of which can be absent), they act synergistically in the high-temperature resistant fluid-solidified soil, significantly improving the mechanical properties and heat resistance of the material.

[0083] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high temperature resistant fluidized solidified soil, characterized in that: It includes slag, curing agent and high temperature resistant reinforcing agent, and the weight ratio is (4.5-8.5): (0.5-1): (0.5-5) respectively; wherein the high temperature resistant reinforcing agent includes alumina, sodium silicate and nano titanium dioxide.

2. The high temperature resistant fluidized solidified soil according to claim 1, characterized in that: The curing agent comprises cement, lime and fly ash in a weight ratio of 2:1:2 respectively.

3. The high temperature resistant fluidized solidified soil according to claim 2, characterized in that: In the curing agent, the cement is silicate cement with a specific surface area of ​​≥300m 2 / kg; lime is quicklime, with a specific surface area of ​​≥400m 2 / kg; fly ash is secondary fly ash, with a specific surface area of ​​≥600m 2 / kg.

4. The high temperature resistant fluidized solidified soil according to claim 1, characterized in that: In the high temperature resistant reinforcing agent, the purity of aluminum oxide is ≥99%, the purity of sodium silicate is ≥99%, and the particle size of nano titanium dioxide is 10-100nm, and the purity is ≥99%.

5. The high temperature resistant fluidized solidified soil according to claim 1, characterized in that: In the high temperature resistant reinforcing agent, the weight ratios of alumina, sodium silicate and nano titanium dioxide are 4:4:1 respectively.

6. The high temperature resistant fluidized solidified soil according to any one of claims 1 to 5, characterized in that: Also includes water reducing agent and water.

7. The high temperature resistant fluidized solidified soil according to claim 6, characterized in that: The mixing amount of the water reducing agent is 0.5% of the weight ratio of the slag soil, and the mixing amount of water is 30% of the weight ratio of the slag soil.

8. The high temperature resistant fluidized solidified soil according to claim 6, characterized in that: The water reducer is a polycarboxylic acid high efficiency water reducer.

9. A method for preparing high temperature resistant fluidized solidified soil according to any one of claims 1 to 8, characterized in that: The steps include: (1) Mixing the slag, the curing agent and the high temperature resistant reinforcing agent uniformly to form a mixture; (2) adding water and a water reducing agent to the mixture and stirring evenly to form a fluidized solidified soil slurry; (3) pouring the fluidized solidified soil slurry into a mold for molding; (4) Maintain the solidified soil after forming until it reaches the specified age.

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