A high-content emulsified alkali-slag soil reinforcement material and its preparation method and application

Abstract

The present invention discloses a high-dosage emulsified alkali slag soil reinforcement material and a preparation method and application thereof. The high-dosage emulsified alkali slag soil reinforcement material of the present invention is prepared by mixing emulsified alkali slag with a stabilizer. The specific process is: mixing alkali slag with water to make it in an emulsion state to obtain emulsified alkali slag, then adding a stabilizer, and stirring the fully formed emulsion material to obtain the high-dosage emulsified alkali slag soil reinforcement material. First, the present invention adopts alkali slag in an emulsion state, and there will be no caking and uneven stirring during the construction process, which reduces the cost of alkali slag preservation, and can widely use the currently remaining alkali slag; the construction difficulty is greatly reduced, and no special on-site soil-alkali slag mixing machinery is required, and simple spreading is sufficient, and the natural flow of liquid makes the material mixing more uniform. Secondly, the present invention improves the moisture content stability of high-dosage alkali slag soil, improves the volume stability of high-dosage alkali slag soil, and improves the strength of high-dosage alkali slag soil.

Description

Technical Field

[0001] The invention belongs to the technical field of building materials, and relates to an alkali-slag soil reinforcement material, in particular to a high-dosage emulsified alkali-slag soil reinforcement material, and a preparation method and application thereof. Background Art

[0002] Alkali residue is the waste residue discharged during the process of making alkali by the ammonia-soda process. The annual production of alkali by the ammonia-soda process in my country can reach 4.21 million tons. Due to the characteristics of the soda ash production process of the ammonia-soda process, 0.3 tons of alkali residue is discharged for every ton of soda ash produced. For a factory with an annual output of 800,000 tons of soda ash, the annual cost of waste residue discharge is about 10 million yuan. In general, the alkali residue is treated by surface accumulation. After a large amount of alkali residue is deposited, a "white sea" is formed, causing pollution to the surrounding sea areas.

[0003] At present, using alkali slag, especially alkali slag with high dosage, as engineering soil for filling projects is an effective way to deal with alkali slag on a large scale. However, when alkali slag is used in large quantities in road soil reinforcement materials and subbase soil improvement, large amounts of alkali slag bring many construction problems, including cracking, poor volume stability, reduced bearing capacity, and uneven solid-solid mixing that makes it difficult to ensure project quality. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a high-dosage emulsified alkali slag soil reinforcement material, which is composed of emulsified alkali slag and a stabilizer, solves the problem of difficulty in treating alkali slag waste, turns waste into treasure, has obvious social and economic benefits, and has broad prospects.

[0005] The present invention is achieved through the following technical solutions:

[0006] A high-dosage emulsified alkali slag soil reinforcement material consists of emulsified alkali slag and a stabilizer, wherein the stabilizer comprises a powder and an aqueous solution.

[0007] Furthermore, the emulsified alkali residue is prepared by stirring and mixing the alkali residue with water.

[0008] Furthermore, the powder is composed of the following raw materials in parts by mass: 0.2 parts of wood or bamboo fiber, 0.3 parts of pregelatinized starch, 0.2 parts of polyacrylamide, and 0.3 parts of blast furnace slag; the aqueous solution is composed of the following raw materials in parts by mass: 0.05 parts of styrene acrylic emulsion and 0.05 parts of alkali activator.

[0009] Furthermore, the wood or bamboo fiber is made by drying wood or bamboo, heating, rolling, soaking and drying; the pregelatinized starch is modified starch, specifically, starch particles are partially or completely broken by chemical or mechanical methods; the polyacrylamide is a cationic polyacrylamide substance with a molecular weight of 180,000; the blast furnace slag powder is a molten product with calcium aluminosilicate as the main component obtained by the iron smelting plant in the blast furnace when smelting pig iron, and the industrial solid waste residue obtained after granulation after water quenching is crushed, and the grade is S105; the alkali activator is a sodium hydroxide solution with a concentration of 10 mol / l.

[0010] A further improvement of the present invention is:

[0011] A method for preparing a high-dosage emulsified alkali slag soil reinforcement material comprises the following steps: mixing the alkali slag with water to make it in an emulsion state to obtain emulsified alkali slag, adding powder, stirring to fully form a high-dosage emulsified alkali slag emulsion material, and mixing the water agent and storing it separately.

[0012] Furthermore, the weight ratio of the alkali slag, water, powder and aqueous solution is 8:10:0.1:0.01; the stabilizer is composed of the following raw materials in parts by weight: 0.2 parts of wood or bamboo fiber, 0.3 parts of pregelatinized starch, 0.2 parts of polyacrylamide, and 0.3 parts of blast furnace slag; the aqueous solution is composed of the following raw materials in parts by weight: 0.05 parts of styrene-acrylic emulsion and 0.05 parts of alkali activator.

[0013] Furthermore, the wood or bamboo fiber is made by drying wood or bamboo, heating, rolling, soaking and drying; the pregelatinized starch is modified starch, specifically, starch particles are partially or completely broken by chemical or mechanical methods; the polyacrylamide is a cationic polyacrylamide substance with a molecular weight of 180,000; the blast furnace slag powder is a molten product with calcium aluminosilicate as the main component obtained by the iron smelting plant in the blast furnace when smelting pig iron, and the industrial solid waste slag is obtained after granulation after water quenching, and the grade is S105; the alkali activator is a sodium hydroxide solution with a concentration of 10 mol / l.

[0014] A further improvement of the present invention is:

[0015] Application of a high-content emulsified alkali-slag soil reinforcement material in improving engineering soil.

[0016] Furthermore, the application of high-content emulsified alkali-slag soil reinforcement material in improving engineering soil specifically includes the following steps:

[0017] (1) Spread the high-volume emulsified alkali-slag soil reinforcement material in an emulsion state evenly on the roadbed with designed moisture content or other foundation soil surface that needs to be improved, or mix it evenly with the engineering soil, and carry out the first rolling;

[0018] (2) Spread the water agent on the surface of the primary compacted soil, and immediately carry out the second rolling and sealing maintenance;

[0019] (3) Construction is completed after 24 days when the strength is reached.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention mixes alkali residue with water to make it in an emulsion state to obtain emulsified alkali residue. The alkali residue in the emulsion state is mainly a saturated solution of a strong electrolyte and an insoluble weak electrolyte. Compared with solid alkali residue, firstly, there will be no agglomeration and uneven stirring during the construction process, which reduces the cost of alkali residue preservation and can widely use the residual alkali residue at present; secondly, the construction difficulty is greatly reduced, and no special on-site soil-alkali residue mixing machinery is required. Simple spreading is sufficient, and the natural flow of liquid makes the material mixing more uniform; thirdly, when solid alkali residue is used, the alkali residue dosage is difficult to exceed 10%. The results of engineering tests show that the uneven expansion and water absorption and cracking of alkali residue soil exceeding the dosage are serious. Emulsified alkali residue can increase the overall alkali residue dosage;

[0022] 2. The pregelatinized starch and polyacrylamide used in the present invention improve the problems of difficulty in adjusting the optimal moisture content of high-doped alkali slag soil, and high water absorption of alkali slag containing strong electrolytes leading to unstable moisture content of soil reinforcement materials.

[0023] 3. The fiber used in the present invention can improve the volume instability problem caused by high-dosage alkali slag soil, and can improve the toughness of soil reinforcement materials.

[0024] 4. The blast furnace slag powder, alkali activator and excess alkali slag components used in the present invention can form a gelling material with stable strength in the soil in the later stage, thereby improving the bearing capacity of the soil.

[0025] 5. Different from traditional soil reinforcement materials, the soil reinforcement material obtained by this method has an overall low cost. The stabilizer separates the powder and the water agent, which is conducive to preservation and greatly improves the engineering properties of the soil reinforcement material.

[0026] 6. At the microscopic level, the application of fiber materials of different fineness produces a spatial steric effect, which allows the insoluble matter in the alkali residue to be stably present in the emulsion, making it convenient for the alkali residue emulsion to have a longer timeliness during construction and storage.

[0027] 7. The soil reinforcement material obtained by construction with emulsified alkali slag with stabilizer has stable material strength and is improved to varying degrees. Due to the effect of fibers, its toughness and bending resistance are greatly improved.

[0028] 8. The current alkali residue utilization dosage is relatively low, while the current alkali residue waste output is huge. The present invention can increase the alkali residue dosage to more than 15%, which is specifically determined by the soil moisture content and soil properties at the project site. DETAILED DESCRIPTION

[0029] The present invention is described in detail below in conjunction with specific embodiments. Note: The amount of alkali residue added in the embodiments of the present invention is calculated using the external addition method in engineering.

[0030] Example 1

[0031] This embodiment provides a preparation method and application of a high-dosage emulsified alkali-slag soil reinforcement material, which specifically includes the following steps:

[0032] (1) Preparation of stabilizer:

[0033] Powder: 0.2 parts of wood (bamboo) fiber; 0.3 parts of pregelatinized starch; 0.2 parts of polyacrylamide; 0.3 parts of blast furnace slag; after pregelatinized starch, polyacrylamide and blast furnace slag powder are mixed evenly according to the proportion, continue to add the fiber and stir to form a fiber-powder;

[0034] Water solution: 0.05 parts of alkali activator; 0.05 parts of styrene acrylic emulsion;

[0035] (2) 8 parts of alkali residue are mixed with 10 parts of water to make them in an emulsion state to obtain emulsified alkali residue, and then 0.1 parts of powder are added and stirred to form an alkali residue soil reinforcement material emulsion material;

[0036] (3) Mix evenly with the engineering soil to form an alkali slag-soil composite with an alkali slag content of 5% for the first compaction;

[0037] (4) Then, sprinkle 0.01 part of the aqueous solution on the surface of the initially compacted soil, compress it into a 5 cm cylindrical standard specimen, and wrap it with plastic wrap for curing;

[0038] (5) After 24 days of full curing, standard specimen A1 was completed.

[0039] The comparative example is plain alkali slag without any external additives, the alkali slag content of which is 5%, and the material specimen is N1.

[0040] The two groups carried out indoor tests at the same time. After rolling, the specimens were covered with film for maintenance and the moisture content was tested within 1-72 days. The compaction retention measurement was carried out under the same conditions, and the cracking and strength of the specimens were observed.

[0041] Experimental results: Comparison between material specimens N1 and A1, the moisture content of the control group N1 is shown in the following table, no cracking occurred during the film-covered curing period, and the 72d strength value was 470KPa; the moisture content of the experimental group A1 is shown in the following table, no cracking occurred during the film-covered curing period, and the 72d strength value was 563KPa. It can be seen that in the test results with an alkali residue content of 5%, the moisture content of the soil reinforcement material specimens using external admixtures is relatively stable, and the strength is also improved.

[0042] Table 1 Moisture content change table

[0043] 6 12 18 24 30 36 42 48 72 N1 18.1 18.9 19.7 20.2 20.5 21.1 21.5 22.1 23.2 A1 18.5 18.6 18.7 18.7 18.7 18.7 18.7 18.7 18.7

[0044] Example 2

[0045] This embodiment provides a preparation method and application of a high-dosage emulsified alkali-slag soil reinforcement material, which specifically includes the following steps:

[0046] (1) Preparation of stabilizer:

[0047] Powder: 0.2 parts of wood (bamboo) fiber; 0.3 parts of pregelatinized starch; 0.2 parts of polyacrylamide; 0.3 parts of blast furnace slag; after pregelatinized starch, polyacrylamide and blast furnace slag powder are mixed evenly according to the proportion, continue to add the fiber and stir to form a fiber-powder;

[0048] Water solution: 0.05 parts of alkali activator; 0.05 parts of styrene acrylic emulsion;

[0049] (2) 8 parts of alkali residue are mixed with 10 parts of water to make them in an emulsion state to obtain emulsified alkali residue, 0.1 parts of powder are added, and the mixture is stirred to form an alkali residue soil reinforcement material emulsion material;

[0050] (3) Mix evenly with the engineering soil to form an alkali slag-soil composite with an alkali slag content of 10% for the first compaction;

[0051] (4) Then, sprinkle 0.01 part of the aqueous solution on the surface of the initially compacted soil, compress it into a 5 cm cylindrical standard specimen, and wrap it with plastic wrap for curing;

[0052] (5) After 24 days of full curing, standard specimen A2 is completed.

[0053] The comparative example is plain alkali slag without any external additives, the alkali slag content of which is 10%, and the material specimen is N2.

[0054] The two groups carried out indoor tests at the same time. After rolling, the specimens were covered with film for maintenance and the moisture content was tested within 1-72 days. The compaction retention measurement was carried out under the same conditions, and the cracking and strength of the specimens were observed.

[0055] Experimental results: Comparison between material specimens N2 and A2, the moisture content of control group N2 changes as shown in the table below, the surface is slightly cracked during the film curing period, and the 72d strength value is 375KPa; the moisture content of experimental group A2 is shown in the table below, no cracking occurs during the film curing period, and the 72d strength value is 533KPa. It can be seen that in the test results with 10% alkali slag content, the moisture content of the soil reinforcement material specimens using external admixtures is relatively stable, and the strength is also improved.

[0056] Table 2 Moisture content change table (%)

[0057] time 6 12 18 24 30 36 42 48 72 N2 18.7 20.7 21.4 22.6 23.8 24.1 24.5 25.6 28.8 A2 18.9 20.2 20.2 20.2 20.2 20.2 20.4 20.4 20.4

[0058] Example 3

[0059] This embodiment provides a preparation method and application of a high-dosage emulsified alkali-slag soil reinforcement material, which specifically includes the following steps:

[0060] (1) Preparation of stabilizer:

[0061] Powder: 0.2 parts of wood (bamboo) fiber; 0.3 parts of pregelatinized starch; 0.2 parts of polyacrylamide; 0.3 parts of blast furnace slag; after pregelatinized starch, polyacrylamide and blast furnace slag powder are mixed evenly according to the proportion, continue to add the fiber and stir to form a fiber-powder;

[0062] Water solution: 0.05 parts of alkali activator; 0.05 parts of styrene acrylic emulsion;

[0063] (2) 8 parts of alkali residue are mixed with 10 parts of water to make them in an emulsion state to obtain emulsified alkali residue, 0.1 parts of powder are added, and the mixture is stirred to form an alkali residue soil reinforcement material emulsion material;

[0064] (3) Mix evenly with the engineering soil to form an alkali slag-soil composite with an alkali slag content of 15% for the first compaction;

[0065] (4) Then, sprinkle 0.01 part of the aqueous solution on the surface of the initially compacted soil, compress it into a 5 cm cylindrical standard specimen, and wrap it with plastic wrap for curing;

[0066] (5) After 24 days of full curing, standard specimen A3 was completed.

[0067] The comparative example is plain alkali slag without any external additives, the alkali slag content of which is 15%, and the material specimen is N3.

[0068] The two groups carried out indoor tests at the same time. After rolling, the specimens were covered with film for maintenance and the moisture content was tested within 1-72 days. The compaction retention measurement was carried out under the same conditions, and the cracking and strength of the specimens were observed.

[0069] Experimental results: Comparison between material specimens N3 and A3, the moisture content of the control group N3 is shown in the following table, cracking occurred during the film-covered curing period, and the 72d strength value was 329KPa; the moisture content of the experimental group A3 is shown in the following table, no cracking occurred during the film-covered curing period, and the 72d strength value was 481KPa. It can be seen that in the test results with an alkali slag content of 15%, the moisture content of the soil reinforcement material specimens using external admixtures is relatively stable, and the strength is significantly improved.

[0070] Table 3 Moisture content change table

[0071] time 6 12 18 24 30 36 42 48 72 N3 19.8 20.7 22.1 24.2 27.4 28.9 31.5 32.6 33.8 A3 18.9 19.4 19.9 20.1 20.3 20.4 20.7 20.9 20.9

[0072] Example 4

[0073] This embodiment provides a preparation method and application of a high-dosage emulsified alkali-slag soil reinforcement material, which specifically includes the following steps:

[0074] (1) Preparation of stabilizer:

[0075] Powder: 0.2 parts of wood (bamboo) fiber; 0.3 parts of pregelatinized starch; 0.2 parts of polyacrylamide; 0.3 parts of blast furnace slag; after pregelatinized starch, polyacrylamide and blast furnace slag powder are mixed evenly according to the proportion, continue to add the fiber and stir to form a fiber-powder;

[0076] Water solution: 0.05 parts of alkali activator; 0.05 parts of styrene acrylic emulsion;

[0077] (2) 8 parts of alkali residue are mixed with 10 parts of water to make them in an emulsion state to obtain emulsified alkali residue, 0.1 parts of powder are added, and the mixture is stirred to form an alkali residue soil reinforcement material emulsion material;

[0078] (3) Mix evenly with the engineering soil to form an alkali slag-soil composite with an alkali slag content of 20% for the first compaction;

[0079] (4) Then, sprinkle 0.01 part of the aqueous solution on the surface of the initially compacted soil, compress it into a 5 cm cylindrical standard specimen, and wrap it with plastic wrap for curing;

[0080] (5) After 24 days of full curing, standard specimen A4 was completed.

[0081] The comparative example is plain alkali slag soil without any external additives, the alkali slag content of which is 20%, and the material specimen is N4.

[0082] The two groups carried out indoor tests at the same time. After rolling, the specimens were covered with film for maintenance and the moisture content was tested within 1-72 days. The compaction retention measurement was carried out under the same conditions, and the cracking and strength of the specimens were observed.

[0083] Experimental results: Comparison between material specimens N4 and A4, the moisture content of the control group N4 is shown in the following table. During the film-covered curing period, severe cracking occurred, and the 72d strength value decreased to 192KPa; the moisture content of the experimental group A4 is shown in the following table. No cracking occurred during the film-covered curing period, and the 72d strength value was 426KPa. It can be seen that in the test results with an alkali residue content of 20%, the moisture content of the soil reinforcement material specimens using external admixtures is still relatively stable, and the strength is significantly improved.

[0084] Table 4 Moisture content change table

[0085] time 6 12 18 24 30 36 42 48 72 N4 21.6 22.9 24.1 27.2 29.4 32.6 34.8 35.1 36.7 A4 20.5 20.7 20.8 20.9 21.0 21.3 21.6 22.0 22.1

[0086] Example 5

[0087] This embodiment provides a preparation method and application of a high-dosage emulsified alkali-slag soil reinforcement material, which specifically includes the following steps:

[0088] (1) Preparation of stabilizer:

[0089] Powder: 0.2 parts of wood (bamboo) fiber; 0.3 parts of pregelatinized starch; 0.2 parts of polyacrylamide; 0.3 parts of blast furnace slag; after pregelatinized starch, polyacrylamide and blast furnace slag powder are mixed evenly according to the proportion, continue to add the fiber and stir to form a fiber-powder;

[0090] Water solution: 0.05 parts of alkali activator; 0.05 parts of styrene acrylic emulsion;

[0091] (2) 8 parts of alkali residue are mixed with 10 parts of water to make them in an emulsion state to obtain emulsified alkali residue, 0.1 parts of powder are added, and the mixture is stirred to form an alkali residue soil reinforcement material emulsion material;

[0092] (3) Spread evenly to the designed moisture content and stir well on the roadbed or other foundation soil surface that needs to be improved and perform the first rolling;

[0093] (4) Then, sprinkle 0.01 part of the aqueous solution on the surface of the initially compacted soil, compress it into a 5 cm cylindrical standard specimen, and wrap it with plastic wrap for curing;

[0094] (5) After 24 days of full curing, standard specimen A5 was completed.

[0095] The comparative example is plain alkali slag without any external additives, the alkali slag content of which is 25%, and the material specimen is N5.

[0096] The two groups carried out indoor tests at the same time. After rolling, the specimens were covered with film for maintenance and the moisture content was tested within 1-72 days. The compaction retention measurement was carried out under the same conditions, and the cracking and strength of the specimens were observed.

[0097] Experimental results: Comparing material specimens N5 and A5, the moisture content of the control group N4 is shown in the following table. During the film-covered curing period, severe cracking occurred, and the 72d strength value was reduced to 151KPa. The moisture content of the experimental group A5 is shown in the following table. No cracking occurred during the film-covered curing period, and the 72d strength value was 387KPa. It can be seen that in the test results with an alkali residue content of 20%, the moisture content of the soil reinforcement material specimens using external admixtures is still relatively stable, and the strength is significantly improved.

[0098] Table 5 Moisture content change table

[0099] time 6 12 18 24 30 36 42 48 72 N5 21.6 22.0 24.8 27.3 29.4 33.9 37.7 38.7 39.2 A5 21.0 21.5 21.6 21.7 22.4 22.6 24 24.5 24.9

[0100] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-dosage emulsified alkali-containing slag reinforcement material, characterized in that: It is composed of emulsified alkali residue and stabilizer, wherein the stabilizer includes powder and aqueous solution; The emulsified alkali residue is prepared by stirring and mixing alkali residue and water; The powder is composed of the following raw materials in parts by weight: 0.2 parts of wood or bamboo fiber, 0.3 parts of pregelatinized starch, 0.2 parts of polyacrylamide, and 0.3 parts of blast furnace slag; The aqueous solution is composed of the following raw materials in parts by mass: 0.05 parts of styrene-acrylic emulsion and 0.05 parts of alkali activator.

2. The high-dosage emulsified alkali-containing slag reinforcement material according to claim 1, characterized in that: The wood or bamboo fiber is made by heating, rolling, soaking and drying wood or bamboo after drying; the pregelatinized starch is modified starch, specifically, starch particles are partially or completely broken by chemical or mechanical methods; the polyacrylamide is a cationic polyacrylamide substance with a molecular weight of 180,000; the blast furnace slag powder is a molten product with calcium aluminosilicate as the main component obtained by the iron smelting plant in the blast furnace when smelting pig iron, and the industrial solid waste residue is obtained after granulation after water quenching, and the grade is S105; the alkali activator is a sodium hydroxide solution with a concentration of 10 mol / l.

3. The method for preparing a high-dosage emulsified alkali-slag reinforcement material according to claim 1, characterized in that: The method comprises the following steps: mixing alkali residue with water to make it in an emulsion state to obtain emulsified alkali residue, adding powder, stirring fully to form a high-dosage emulsified alkali residue emulsion material, and mixing the aqueous solution and storing separately.

4. The method for preparing a high-dosage emulsified alkali-slag reinforcement material according to claim 3, characterized in that: The weight ratio of the alkali residue, water, powder and aqueous solution is 8:10:0.1:0.

01.

5. Application of a high-content emulsified alkali-slag soil reinforcement material as claimed in claim 1 in improving engineering soil.

6. The use of a high-content emulsified alkali-slag soil reinforcement material in improving engineering soil according to claim 5, characterized in that: The specific steps include: (1) Spread the high-volume emulsified alkali-slag soil reinforcement material in an emulsion state evenly on the roadbed with designed moisture content or other foundation soil surface that needs to be improved, or mix it evenly with the engineering soil, and carry out the first rolling; (2) Spread the water agent on the surface of the primary compacted soil, and immediately carry out the second rolling and sealing maintenance; (3) Construction is completed after 24 days when the strength is reached.