Soil stabilizer and preparation method therefor, and road surface paving method

Abstract

The present application relates to the technical field of road construction, and discloses a soil stabilizer and a preparation method therefor, as well as a road surface paving method. The soil stabilizer provided in the present application is a liquid stabilizer that can solidify soil in-situ, improve soil strength, and increase the stability of the soil structure. Therefore, the described soil stabilizer can directly treat soil into a road surface layer, solving the problem in related technologies that soil stabilizers are prone to cracking after solidification and cannot be used for paving road surface layers. Moreover, the soil stabilizer of the present application is environmentally friendly and pollution-free, does not cause ecological problems, and is beneficial to environmental protection. In addition, soil solidified by using said soil stabilizer can be directly used for road surface paving, which can reduce the use of cement and asphalt, save construction costs, and the solidified soil does not cause hardening of the road surface, making it particularly suitable for road construction inside mining areas and high-standard farmland construction.

Description

Soil solidifying agent, preparation method thereof, and road surface paving method

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the China Patent Office on December 25, 2023, with application number 202311796153.7 and invention name “Soil solidifier, preparation method thereof and method for paving road surface layer”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the technical field of road construction, and in particular to a soil solidifying agent and a preparation method thereof, as well as a method for paving a road surface layer. Background Art

[0004] Soil stabilizers are a new type of energy-saving and environmentally friendly geocomposite material that can be used to enhance or improve the engineering properties of soil. With the advancement of science and technology, soil stabilizers have evolved from traditional inorganic materials such as cement, fly ash, and lime to organic materials and composite materials combining these two materials. Their form has also evolved from powdered stabilizers to liquid stabilizers. In engineering applications, simply adding a specific amount of soil stabilizer based on the soil's physical and chemical properties, followed by a series of mixing and compaction processes, can achieve the desired engineering performance.

[0005] Chinese patent CN107032710A discloses a composite soil solidifier, which is made by mixing solid sulfur ash as the main raw material, adding (a small amount of) ordinary Portland cement, quicklime, activator, early strength agent, silica fume, and polyacrylamide and then mixing them evenly.

[0006] In the process of realizing this application, the inventors found that the above-mentioned soil solidifier in the prior art can be used to improve the roadbed structure, but the soil solidifier is prone to cracking after solidification and cannot be directly used for paving the road surface. Moreover, the soil solidifier will pollute the environment, causing a series of ecological problems, which is not conducive to environmental protection. Summary of the Invention

[0007] In view of this, the present application provides a soil solidifier and a preparation method thereof, as well as a method for paving a road surface layer, to solve the problem in the prior art that the soil solidifier is prone to cracking after curing and cannot be directly used for paving the road surface layer.

[0008] In a first aspect, the present application provides a soil solidifying agent. The raw materials of the soil solidifying agent include the following components in parts by weight:

[0009] 20-30 parts by weight of aluminum silicate, 5-15 parts by weight of sodium stearate, 15-25 parts by weight of sodium palmitate, 10-20 parts by weight of benzyl alcohol, 30-40 parts by weight of sodium chloride, 5-15 parts by weight of sodium sulfate, and 500-600 parts by weight of water.

[0010] The soil solidifier provided in the present application is a liquid solidifier, which can solidify the soil on site, improve the strength of the soil, and increase the stability of the soil structure. Therefore, the soil solidifier can directly process the soil into a road surface layer, solving the problem that the soil solidifier in the related art cannot be used for paving the road surface layer because it is easy to crack after solidification; and the soil solidifier of the present application is environmentally friendly and pollution-free, will not cause ecological problems, and is beneficial to environmental protection; in addition, the soil solidified by the soil solidifier can be directly used for paving the road surface layer, which can reduce the use of cement and asphalt, save construction costs, and the solidified soil will not cause the road surface layer to harden, which is particularly suitable for the construction of internal roads in mining areas and roads during the construction of high-standard farmland.

[0011] In a second aspect, the present application provides the use of the above-mentioned soil solidifier in road surface paving.

[0012] In an optional embodiment, the road surface layer is a mining road surface layer or a road surface layer involved in the construction of high-standard farmland. Relevant policies stipulate that hardened pavement shall not be used for internal roads in mining areas, and high-standard farmland construction requires that cement or concrete hardened pavement shall not be used.

[0013] In a third aspect, the present application provides a mixture-soil composition for road surface paving, wherein the mixture-soil composition comprises cement, lime soil and the above-mentioned soil solidifying agent.

[0014] In an optional embodiment, in parts by weight, the amount of cement is 500 to 2000 parts by weight, the amount of ash soil is 10,000 to 20,000 parts by weight, and the amount of soil solidifier is 2 to 8 parts by weight.

[0015] In a fourth aspect, the present application provides a method for preparing the soil solidifying agent, the method comprising the following steps:

[0016] Adding sodium chloride and sodium sulfate to water, heating and stirring until mixed, to obtain a first solution;

[0017] adding sodium stearate, sodium palmitate, and benzyl alcohol to the first solution, heating and stirring until uniformly mixed, to obtain a second solution;

[0018] Aluminum silicate is added to the second solution, heated and stirred until mixed to obtain the soil solidifying agent.

[0019] In an optional embodiment, after sodium chloride and sodium sulfate are added to water, the heating temperature is controlled to be 30-40° C. and the stirring speed is controlled to be 100-200 r / min;

[0020] and / or, after adding sodium stearate, sodium palmitate and benzyl alcohol to the first solution, controlling the heating temperature to 30-40° C., the stirring speed to 200-300 r / min, and the stirring time to 3-4 h;

[0021] And / or, after adding aluminum silicate to the second solution, the heating temperature is controlled to be 30-40° C., the stirring speed is controlled to be 200-300 r / min, and the stirring is performed for at least 1 hour.

[0022] In a fifth aspect, the present application provides a method for paving a road surface layer, the paving method comprising the following steps:

[0023] Spread cement and lime soil on the soil of the working surface and mix them evenly to obtain a mixed soil layer;

[0024] Spraying the soil solidifying agent on the mixed soil layer and mixing evenly to obtain a soil layer to be solidified;

[0025] The soil layer to be solidified is leveled and compacted.

[0026] In an optional embodiment, when the mixed soil layer is obtained, the process further comprises:

[0027] Remove the incompletely digested ash blocks and soil particles with a particle size of more than 5 mm, and at the same time control the measured moisture content of the soil during the mixing process to be greater than the optimal moisture content; optionally, the optimal moisture content is 18-22%.

[0028] Furthermore, to avoid the formation of interlayers of raw soil during the mixing process, a mixer is used to mix the mixture from both sides of the soil layer, and the mixing depth reaches 1cm in the roadbed. Before laying cement and lime soil on the working surface soil, the soil is pretreated to remove clods, tree roots, grass and other debris from the soil (raw soil) to ensure that the raw soil meets the construction requirements. At the same time, when pretreating some raw soil with poor workability, lime is used to mix the raw soil, and then the material is allowed to stand for two hours before use.

[0029] In an optional embodiment, before spraying the soil solidifying agent on the mixed soil layer, the process further includes diluting the soil solidifying agent, wherein the dilution factor of the soil solidifying agent is determined based on the measured soil moisture content and the optimum soil moisture content;

[0030] And / or, after spraying the soil solidifier on the mixed soil layer, let it stand for 30 to 60 minutes before mixing it evenly. For example, after spraying the soil solidifier, let it stand for 40 minutes before starting to mix it, and mix it evenly three times to ensure that the color of the mixed material treated with the soil solidifier is consistent. During the mixing process, it is necessary to sort out any missing soil lumps with a particle size of more than 5 mm.

[0031] Furthermore, when the soil solidifying agent is sprayed on the mixed soil layer, it is necessary to spray continuously to ensure that the soil solidifying agent can be sprayed evenly to prevent excessive spraying, local omissions, etc.

[0032] In an optional embodiment, the rolling includes:

[0033] First, use a 10-15t roller to perform static compaction for 1-3 times, and then use a 15-20t roller to perform strong vibration compaction for 3-5 times. Optionally, the compaction speed of the 10-15t roller is 2-3 km / h, and the compaction speed of the 15-20t roller is 3-4 km / h.

[0034] For example, after using a motor grader to level the soil layer to be solidified, a roller is used to perform one static roll (for a 12t roller), followed by three rolls (for an 18t roller). The number of rolls on both sides of the road is increased to seven. After the rolls are completed, a leveler is used to inspect the road surface for any low spots, which are then repaired. The 12t roller has a rolling speed of 2 km / h, while the 18t roller has a rolling speed of 2.5 km / h. When using the motor grader for leveling, any mixture exceeding the paving thickness is scraped to the outside. During the leveling process, the road crown and slope need to be controlled, and the joints of the road surface need to be treated.

[0035] and / or, after the completion of the rolling:

[0036] The moisture content of the road surface soil is measured. If the measured moisture content of the road surface soil is lower than the optimum moisture content, the road surface soil is rehydrated and rolled again. During the rolling process, the road must be driven at a constant speed. U-turns or sudden braking are not allowed to avoid damaging the surface structure of the cured pavement layer. In high-temperature environments, a sprinkler truck is required to add moisture to the road surface.

[0037] Among them, the standard of the optimal moisture content can be adjusted based on the construction area. In arid areas with low groundwater levels and an average annual rainfall of less than 150 mm, the compaction standard can usually be reduced by 2%-3%. In some overly humid areas with a moisture coefficient greater than 2 or an average annual rainfall of more than 2000 mm, as well as in rainy areas with difficult drying conditions, the soil needs to be treated before rolling. DETAILED DESCRIPTION

[0038] The following examples are provided to further better understand the present application, but are not limited to the best implementation mode described herein, and do not limit the content and protection scope of the present application. Any product identical or similar to the present application obtained by anyone under the inspiration of the present application or by combining the features of the present application with other prior arts shall fall within the scope of protection of the present application.

[0039] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in this field can be used. If the manufacturer of the reagents or instruments is not specified, they are all commercially available conventional reagents.

[0040] The present application is further described in detail below with reference to specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in this application.

[0041] Example 1

[0042] This embodiment is actually to renovate a road in a mining area, and the specific steps are as follows:

[0043] (1) Preparation of soil solidifier:

[0044] ① Add 6 kg of water to a container, then add 0.4 kg of sodium chloride and 0.1 kg of sodium sulfate solid in sequence, heat to 35°C, and stir the solution at a speed of 160 r / min during the heating process to mix uniformly to obtain a first solution;

[0045] ② Add 0.1 kg of sodium stearate, 0.2 kg of sodium palmitate and 0.1 kg of benzyl alcohol to the mixed first solution, and continue stirring at 300 r / min at 35°C for 4 hours to obtain a second solution;

[0046] ③ Add 0.2 kg of aluminum silicate to the mixed second solution, continue stirring at 300 rpm at 35°C for 1 hour, and cool to room temperature to obtain a liquid soil solidifier.

[0047] The raw materials used in the preparation of the above soil solidifier are as follows:

[0048] 10 parts by weight of aluminum silicate, 10 parts by weight of sodium stearate, 20 parts by weight of sodium palmitate, 10 parts by weight of benzyl alcohol, 40 parts by weight of sodium chloride, 10 parts by weight of sodium sulfate, and 600 parts by weight of water;

[0049] (2) 1 ton of cement (Portland cement) and 10 ton of lime soil are laid on the road surface and spread with a scraper to ensure that the paving area of ​​each portion of cement and lime soil is the same. Then, a mixer is used to evenly mix the cement and lime soil, and a bulldozer is used to level the mixture to obtain a mixed soil layer.

[0050] Among them, during the mixing process of the mixer, the ash blocks that have not been completely digested and the soil particles with a particle size of more than 5mm are removed in time. At the same time, during the mixing process, an appropriate amount of water needs to be added so that the measured water content is greater than the optimal water content (20%). The raw soil needs to be pretreated to clean the soil blocks, tree roots, turf and other debris in the raw soil to ensure that the raw soil meets the construction requirements. At the same time, when pretreating some raw soil with poor workability, it is necessary to use lime to mix the raw soil, and then let the material sit for two hours before use;

[0051] (3) diluting the soil solidifying agent prepared in step (1) by 10,000 times, and evenly spraying the diluted soil solidifying agent on the mixed soil layer obtained in step (2) with a sprinkler truck, and then using a mixer to start mixing from both sides of the mixed soil layer to obtain a soil layer to be solidified, wherein the mixing depth needs to be 1 cm to the road base to ensure that no bare soil interlayer appears during the mixing process;

[0052] Among them, during the spraying process of the soil solidifier, it is necessary to spray continuously and uninterruptedly to ensure that the soil solidifier can be sprayed evenly to prevent excessive spraying, local omissions, etc.; the dilution of the soil solidifier requires the water content of the mixed soil layer to be measured first, and the dilution multiple of the soil solidifier is determined according to the optimal water content and the measured water content. After the soil solidifier is sprayed, it is necessary to let it stand for 40 minutes before starting to mix the material, and mix it evenly three times to make the color of the mixture treated with the soil solidifier consistent. During the mixing process, it is necessary to pick out the missed soil blocks with a particle size of more than 5mm;

[0053] In steps (2)-(3), in parts by weight, the amount of cement used is 1000 parts by weight, the amount of lime soil used is 10,000 parts by weight, and the amount of soil solidifier used is 7.1 parts by weight;

[0054] (4) Using a grader to level the soil layer to be solidified obtained in step (3), after leveling, using a 12t roller to statically press the road surface for one round trip, and then using an 18t roller to vigorously roll the road surface for three round trips, increasing the number of rolling times on both sides of the road surface to seven times. After rolling, use a leveler to check the leveling of the road surface to detect whether there are local low-lying areas and repair the low-lying areas;

[0055] Among them, the rolling speed of the 12t roller is 2km / h, and the rolling speed of the 18t roller is 2.5km / h. When the grader is leveling, the mixture that exceeds the paving thickness will be scraped to the outside. During the leveling process, the road arch and slope need to be controlled, and the joints of the road surface need to be treated; after the roller is completed, the moisture content of the soil layer needs to be tested. The optimal moisture content is set to 18%-22%. When the moisture content is lower than the optimal moisture content, it is sprinkled with water. After the moisture content reaches the optimal moisture content, it is rolled again. During the rolling process, it is necessary to maintain a constant speed. U-turns or sudden braking are not allowed to avoid damaging the surface structure of the cured treatment layer of the road surface. In high-temperature environments, a sprinkler truck is required to add moisture to the road surface.

[0056] Example 2

[0057] The road in the same mining area was renovated according to the method of Example 1, except that in step (1) of this embodiment, the amount of water used was 5 kg, the amount of sodium chloride used was 0.3 kg, the amount of sodium sulfate used was 0.05 kg, the amount of sodium stearate used was 0.05 kg, the amount of sodium palmitate used was 0.15 kg, the amount of benzyl alcohol used was 0.1 kg, and the amount of aluminum silicate used was 0.2 kg.

[0058] The raw materials used in the preparation process of the soil solidifying agent of this embodiment are as follows:

[0059] 20 parts by weight of aluminum silicate, 5 parts by weight of sodium stearate, 15 parts by weight of sodium palmitate, 10 parts by weight of benzyl alcohol, 30 parts by weight of sodium chloride, 5 parts by weight of sodium sulfate, and 500 parts by weight of water.

[0060] Example 3

[0061] The same mining road was renovated according to the method of Example 1, except that in step (1) of this embodiment, the amount of water used was 6 kg, the amount of sodium chloride used was 0.4 kg, the amount of sodium sulfate used was 0.15 kg, the amount of sodium stearate used was 0.15 kg, the amount of sodium palmitate used was 0.25 kg, the amount of benzyl alcohol used was 0.2 kg, and the amount of aluminum silicate used was 0.3 kg.

[0062] The raw materials used in the preparation process of the soil solidifying agent of this embodiment are as follows:

[0063] 30 parts by weight of aluminum silicate, 15 parts by weight of sodium stearate, 25 parts by weight of sodium palmitate, 20 parts by weight of benzyl alcohol, 40 parts by weight of sodium chloride, 15 parts by weight of sodium sulfate, and 600 parts by weight of water.

[0064] Example 4

[0065] The road in the same mining area was renovated according to the method of Example 1, except that the amount of cement used in step (2) of this example was 500 kg and the amount of ash soil used was 10 t.

[0066] In this embodiment, in parts by weight, the amount of cement used is 500 parts by weight, the amount of ash soil used is 10,000 parts by weight, and the amount of soil solidifier used is 7.1 parts by weight.

[0067] Example 5

[0068] The road in the same mining area was renovated according to the method of Example 1, except that the amount of cement used in step (2) of this example was 800 kg and the amount of ash soil used was 10 t.

[0069] In this embodiment, in parts by weight, the amount of cement used is 800 parts by weight, the amount of lime soil used is 10,000 parts by weight, and the amount of soil solidifier used is 7.1 parts by weight.

[0070] Comparative Example 1

[0071] The same mining road was renovated according to the method of Example 1, except that no sodium chloride was added when preparing the soil solidifying agent in step (1) of this comparative example.

[0072] Comparative Example 2

[0073] The same mining road was renovated according to the method of Example 1, except that no sodium sulfate was added when preparing the soil solidifying agent in step (1) of this comparative example.

[0074] Comparative Example 3

[0075] The same mining road was renovated according to the method of Example 1, except that sodium stearate was not added when preparing the soil solidifying agent in step (1) of this comparative example.

[0076] Comparative Example 4

[0077] The same mining road was renovated according to the method of Example 1, except that sodium palmitate was not added when preparing the soil solidifying agent in step (1) of this comparative example.

[0078] Comparative Example 5

[0079] The same mining road was renovated according to the method of Example 1, except that benzyl alcohol was not added when preparing the soil solidifying agent in step (1) of this comparative example.

[0080] Comparative Example 6

[0081] The same mining road was renovated according to the method of Example 1, except that aluminum silicate was not added when preparing the soil solidifying agent in step (1) of this comparative example.

[0082] Comparative Example 7

[0083] The same mining road was renovated according to the method of Example 1, except that an equal amount of commercially available soil solidifier (manufacturer: AKEYUNG, model: AK 75) was used in this comparative example to replace the soil solidifier prepared in step (1) of Example 1.

[0084] Experimental Example 1

[0085] The soil layers to be solidified obtained in step (3) of Examples 1-5 and Comparative Examples 1-7 were sampled, and specimens were prepared indoors according to the method in JTG E51-2009 "Test Procedure for Stabilized Materials of Inorganic Binders for Highway Engineering". Performance tests were performed after curing at room temperature for 3 days. The test results are shown in Table 1.

[0086] Table 1 Performance test results of each soil layer to be solidified

[0087] As can be seen from Table 1, the mixture obtained by treating with the soil solidifier of the present application has good mechanical properties, rutting resistance, water stability and high and low temperature stability, and meets the technical requirements of road surface materials.

[0088] Experimental Example 2

[0089] The performance index tests of the mining road surface layers constructed in Examples 1-5 and Comparative Examples 1-7 were carried out according to the method in JTG 3450-2019 "Field Test Procedure for Highway Roadbed and Pavement", and the test results are shown in Table 2.

[0090] Table 2 Performance index test results of road surface layers in various mining areas

[0091] It can be seen from Table 2 that the road surface treated with the soil solidifier of the present application has high bearing capacity, small rebound deformation value, small water permeability coefficient, high flatness, and meets the surface paving requirements.

[0092] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A soil stabilizer, characterized in that, The raw materials of the soil stabilizer, in parts by weight, include the following components: 20 - 30 parts by weight of aluminum silicate, 5 - 15 parts by weight of sodium stearate, 15 - 25 parts by weight of sodium palmitate, 10 - 20 parts by weight of benzyl alcohol, 30 - 40 parts by weight of sodium chloride, 5 - 15 parts by weight of sodium sulfate, and 500 - 600 parts by weight of water.

2. Use of the soil stabilizer according to claim 1 in the paving of road surface courses.

3. A mixture soil composition for road surface paving, characterized in that, The mixture soil composition includes cement, lime soil, and the soil stabilizer according to claim 1.

4. The soil mixture composition according to claim 3, characterized in that, In parts by weight, the amount of the cement is 500 - 2000 parts by weight, the amount of the lime soil is 10000 - 20000 parts by weight, and the amount of the soil stabilizer is 2 - 8 parts by weight.

5. The preparation method of the soil stabilizer according to claim 1, characterized in that, The preparation method includes the following steps: Adding sodium chloride and sodium sulfate into water, heating and stirring until evenly mixed to obtain a first solution; Adding sodium stearate, sodium palmitate, and benzyl alcohol into the first solution, heating and stirring until evenly mixed to obtain a second solution; Adding aluminum silicate into the second solution, heating and stirring until evenly mixed to obtain the soil stabilizer.

6. The preparation method according to claim 5, characterized in that, After adding sodium chloride and sodium sulfate into water, controlling the heating temperature to be 30 - 40 °C and the stirring speed to be 100 - 200 r / min; And / or, after adding sodium stearate, sodium palmitate, and benzyl alcohol into the first solution, controlling the heating temperature to be 30 - 40 °C, the stirring speed to be 200 - 300 r / min, and the stirring time to be 3 - 4 h; And / or, after adding aluminum silicate into the second solution, controlling the heating temperature to be 30 - 40 °C, the stirring speed to be 200 - 300 r / min, and stirring for at least 1 h.

7. A method for laying a road surface layer, characterized in that The paving method includes the following steps: Laying the cement and lime soil on the working surface soil and mixing evenly to obtain a mixed soil layer; Spraying the soil stabilizer according to claim 1 on the mixed soil layer and mixing evenly to obtain a soil layer to be solidified; Levelling and compacting the soil layer to be solidified.

8. The laying method according to claim 7, characterized in that, When mixing to obtain the mixed soil layer, it further includes: Removing incompletely slaked lime lumps and soil particles with a particle size exceeding 5 mm, and at the same time controlling the measured water content of the soil during the mixing process to be greater than the optimum water content; Optionally, the optimum water content is 18 - 22%.

9. The laying method according to claim 7 or 8, characterized in that, Before spraying the soil stabilizer on the mixed soil layer, it further includes an operation of diluting the soil stabilizer, wherein the dilution multiple of the soil stabilizer is determined based on the measured water content and the optimum water content of the soil; And / or, after spraying the soil stabilizer on the mixed soil layer, standing for 30 - 60 min and then mixing evenly again.

10. The laying method according to any one of claims 7 to 9, characterized in that, The compaction includes: First, using a 10 - 15 t roller to statically compact for 1 - 3 round trips, and then using a 15 - 20 t roller to strongly vibrate and compact for 3 - 5 round trips; Optionally, the compaction speed of the 10 - 15 t roller is 2 - 3 km / h, and the compaction speed of the 15 - 20 t roller is 3 - 4 km / h; And / or, after the compaction is completed, it further includes: Measure the water content of the road surface soil, and when the measured water content of the road surface soil is lower than the optimum water content, replenish water to the road surface soil and compact it again.

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