Soil solidifying agent and preparation method thereof and road surface laying method

Abstract

The present invention relates to the technical field of road construction, and discloses a soil solidifying agent and a preparation method thereof, as well as a method for paving a road surface layer. The soil solidifying agent provided by the present invention is a liquid solidifying agent, which can solidify the soil on site, improve the strength of the soil, and increase the stability of the soil structure. Therefore, the soil solidifying agent can directly process the soil into a road surface layer, solving the problem that the soil solidifying agent in the related art cannot be used for paving the road surface layer because it is easy to crack after solidification; and the above-mentioned soil solidifying agent of the present invention is environmentally friendly and pollution-free, will not cause ecological problems, and is conducive to environmental protection; in addition, the soil solidified by the soil solidifying agent 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 roads inside mining areas and roads during the construction of high-standard farmland.

Description

Technical Field

[0001] The invention relates to the technical field of road construction, and in particular to a soil solidifying agent and a preparation method thereof, and a method for paving a road surface layer. Background Art

[0002] Soil stabilizer is a new type of energy-saving and environmentally friendly geocomposite material that can be used to enhance or improve the engineering performance of soil. With the development of science and technology, soil stabilizers have gradually evolved from some traditional inorganic materials such as cement, fly ash, lime, etc. to organic materials and composite materials synthesized from inorganic and organic materials. In terms of form, it has also gradually evolved from powdered stabilizers to liquid stabilizers. In engineering applications, it is usually only necessary to add a certain amount of soil stabilizer according to the physical and chemical properties of the soil, and then after a series of mixing and compaction treatments, the engineering performance indicators of the soil can meet the specified requirements.

[0003] Chinese patent CN107032710A discloses a composite soil solidifier, which is made by using sulfur-fixing ash as the main raw material, adding (a small amount of) ordinary Portland cement, quicklime, activator, early strength agent, silica fume, and polyacrylamide and mixing them evenly.

[0004] In the process of realizing the present invention, 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, cause a series of ecological problems, and is not conducive to environmental protection. Summary of the invention

[0005] In view of this, the present invention 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.

[0006] In a first aspect, the present invention provides a soil solidifying agent, wherein the raw materials of the soil solidifying agent include the following components in parts by weight:

[0007] 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.

[0008] The soil solidifying agent provided by the present invention is a liquid solidifying agent, which can solidify the soil on site, improve the strength of the soil, and increase the stability of the soil structure. Therefore, the soil solidifying agent can directly process the soil into a road surface layer, solving the problem that the soil solidifying agent in the related art cannot be used for paving the road surface layer because it is easy to crack after solidification; and the soil solidifying agent of the present invention 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 solidifying agent 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.

[0009] In a second aspect, the present invention provides use of the soil solidifying agent in paving a road surface.

[0010] 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 the construction of high-standard farmland requires that cement or concrete hardened pavement shall not be used.

[0011] In a third aspect, the present invention provides a mixture-soil composition for paving a road surface, wherein the mixture-soil composition comprises cement, lime soil and the above-mentioned soil solidifying agent.

[0012] 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 10000 to 20000 parts by weight, and the amount of soil solidifier is 2 to 8 parts by weight.

[0013] In a fourth aspect, the present invention provides a method for preparing the soil solidifying agent, the method comprising the following steps:

[0014] Adding sodium chloride and sodium sulfate into water, heating and stirring until well mixed, to obtain a first solution;

[0015] Adding sodium stearate, sodium palmitate and benzyl alcohol to the first solution, heating and stirring until mixed, to obtain a second solution;

[0016] Aluminum silicate is added to the second solution, heated and stirred until mixed, to obtain the soil solidifying agent.

[0017] In an optional embodiment, after adding sodium chloride and sodium sulfate to water, the heating temperature is controlled to be 30-40° C. and the stirring speed is controlled to be 100-200 r / min;

[0018] 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;

[0019] 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.

[0020] In a fifth aspect, the present invention provides a method for laying a road surface layer, the method comprising the following steps:

[0021] Spread cement and lime soil on the soil of the working surface and mix them evenly to obtain a mixed soil layer;

[0022] Spraying the soil solidifying agent on the mixed soil layer and mixing evenly to obtain a soil layer to be solidified;

[0023] The soil layer to be solidified is leveled and rolled.

[0024] In an optional embodiment, when the mixed material soil layer is obtained, the process further comprises:

[0025] The incompletely decomposed ash blocks and soil particles with a particle size exceeding 5 mm are removed, and the measured moisture content of the soil during the mixing process is controlled to be greater than the optimal moisture content; optionally, the optimal moisture content is 18-22%.

[0026] Furthermore, in order to avoid the formation of a soil interlayer during the mixing process, a mixer is used to mix from both sides of the mixed soil layer, and the mixing depth reaches 1 cm of the roadbed. Before laying cement and lime soil on the soil of the working surface, the soil is pretreated to clean up the soil (plain soil), including lumps of soil, tree roots, turf and other debris, to ensure that the plain soil meets the construction requirements. At the same time, when pretreating some plain soil with poor workability, lime is needed to mix the plain soil, and then the material is stuffed for two hours before use.

[0027] 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 multiple of the soil solidifying agent is determined based on the measured water content of the soil and the optimum water content;

[0028] And / or, after the soil solidifier is sprayed on the soil layer of the mixture, it is left to stand for 30 to 60 minutes, and then mixed evenly. For example, after the soil solidifier is sprayed, it is left to stand for 40 minutes before mixing, and mixed evenly three times to make the mixture after the soil solidifier is treated with a uniform color. During the mixing process, it is necessary to pick out the missing soil blocks with a particle size of more than 5 mm.

[0029] 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, and the like.

[0030] In an optional embodiment, the rolling includes:

[0031] First, use a 10-15t roller to perform static rolling for 1-3 times, and then use a 15-20t roller to perform strong vibration rolling for 3-5 times; optionally, the rolling speed of the 10-15t roller is 2-3km / h, and the rolling speed of the 15-20t roller is 3-4km / h.

[0032] For example, after using a grader to level the soil layer to be solidified, use a roller to statically press the road surface 1 time (12t roller), and then use strong vibration rolling 3 times (18t roller). Increase the number of rolling times on both sides of the road surface to 7 times. After rolling, use a leveler to level the road surface to detect whether there are local low-lying areas and make up for the low-lying areas. The rolling speed of a 12t roller is 2km / h, and the rolling speed of an 18t roller is 2.5km / h. When using a grader for leveling, scrape the mixture that exceeds the paving thickness to the outside. During the leveling process, it is necessary to control the road humps and slopes, and process the joints of the road surface.

[0033] and / or, after the rolling is completed, including:

[0034] The moisture content of the road surface soil is measured, and when 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 vehicle must maintain a constant speed, and U-turns or sudden braking are not allowed to avoid damaging the surface structure of the road surface curing treatment layer. In a high-temperature use environment, a sprinkler truck is required to add moisture to the road surface.

[0035] 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 wet areas with a moisture coefficient greater than 2 or an average annual rainfall of more than 2000 mm, as well as rainy areas with difficult drying conditions, the soil needs to be treated before rolling. DETAILED DESCRIPTION

[0036] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0037] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0038] The present invention is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed by the present invention.

[0039] Example 1

[0040] This embodiment is actually to renovate a road in a mining area, and the specific steps are as follows:

[0041] (1) Preparation of soil solidifier:

[0042] ① Add 6 kg of water to the container, then add 0.4 kg of sodium chloride and 0.1 kg of sodium sulfate solid in sequence, heat to 35° C. During the heating process, stir the solution at a speed of 160 r / min to mix evenly to obtain a first solution;

[0043] 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 to stir at 300 r / min at 35° C. for 4 h to obtain a second solution;

[0044] ③ Add 0.2 kg of aluminum silicate to the mixed second solution, continue stirring at 300 r / min at 35°C for 1 hour, cool to room temperature, and finally obtain a liquid soil solidifier;

[0045] The raw materials used in the preparation process of the above soil solidifier are as follows:

[0046] 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;

[0047] (2) 1 ton of cement (Portland cement) and 10 ton of lime soil are laid on the road surface, spread with a scraper to ensure that the paving area of ​​each portion of cement and lime soil is the same, then the cement and lime soil are evenly mixed with a mixer, and then the mixture is leveled with a bulldozer to obtain a mixed soil layer;

[0048] 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, it is necessary to add an appropriate amount of water so that the measured water content is greater than the optimal water content (20%). The raw soil needs to be pre-treated, and the soil blocks, tree roots, turf and other debris in the raw soil are cleaned up to ensure that the raw soil meets the construction requirements. At the same time, when pre-treating some raw soils with poor workability, it is necessary to use lime to mix the raw soil, and then suffocate the material for two hours before use;

[0049] (3) diluting the soil solidifying agent prepared in step (1) by 10,000 times, and spraying the diluted soil solidifying agent evenly 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;

[0050] During the spraying process of the soil stabilizer, it is necessary to spray continuously and uninterruptedly to ensure that the soil stabilizer can be sprayed evenly to prevent excessive spraying, local omissions, etc. The dilution of the soil stabilizer requires the actual measurement of the moisture content of the mixed soil layer, and the dilution multiple of the soil stabilizer is determined according to the optimal moisture content and the measured moisture content. After the soil stabilizer is sprayed, it is necessary to leave it for 40 minutes before mixing the material, and mix it evenly three times to make the color of the mixture treated with the soil stabilizer consistent. During the mixing process, it is necessary to pick out the missed soil blocks with a particle size of more than 5mm;

[0051] 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 10000 parts by weight, and the amount of soil solidifier used is 7.1 parts by weight;

[0052] (4) using a land grader to level the soil layer to be solidified obtained in step (3), and after leveling, using a 12t roller to statically press the road surface once, and then using an 18t roller to perform strong vibration rolling three times, and increasing the number of rolling times on both sides of the road surface to 7 times. After rolling, use a leveler to perform a leveling test on the road surface to detect whether there are local low-lying areas, and make up for the low-lying areas;

[0053] 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 finished rolling, the moisture content of the soil layer needs to be tested, and the optimal moisture content is set to 18%-22%. When the moisture content is lower than the optimal moisture content, water it, and roll it again after the moisture content reaches the optimal moisture content. During the rolling process, it is necessary to maintain a uniform speed, and U-turns or sudden brakes are not allowed to avoid damaging the surface structure of the road surface curing treatment layer. In high-temperature use environments, a sprinkler truck is needed to replenish moisture to the road surface.

[0054] Example 2

[0055] 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 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.

[0056] The raw materials used in the preparation process of the soil solidifier of this embodiment are as follows:

[0057] 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.

[0058] Example 3

[0059] 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.

[0060] The raw materials used in the preparation process of the soil solidifier of this embodiment are as follows:

[0061] 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.

[0062] Example 4

[0063] The same mining area road was renovated according to the method of Example 1, except that in step (2) of this example, the amount of cement used was 500 kg and the amount of ash soil used was 10 t.

[0064] 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.

[0065] Example 5

[0066] The same mining road was renovated according to the method of Example 1, except that in step (2) of this example, the amount of cement used was 800 kg and the amount of ash soil used was 10 t.

[0067] In this embodiment, in parts by weight, the amount of cement used is 800 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.

[0068] Comparative Example 1

[0069] 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.

[0070] Comparative Example 2

[0071] 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.

[0072] Comparative Example 3

[0073] 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.

[0074] Comparative Example 4

[0075] 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.

[0076] Comparative Example 5

[0077] 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.

[0078] Comparative Example 6

[0079] The same mining road was renovated according to the method of Example 1, except that no aluminum silicate was added when preparing the soil solidifying agent in step (1) of this comparative example.

[0080] Comparative Example 7

[0081] 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.

[0082] Experimental Example 1

[0083] The soil layers to be solidified obtained in step (3) of Examples 1-5 and Comparative Examples 1-7 were sampled respectively, and specimens were prepared indoors according to the method in JTG E51-2009 "Test Procedure for Stabilized Materials of Inorganic Binders for Highway Engineering". The performance was tested after curing at room temperature for 3 days. The test results are shown in Table 1.

[0084] Table 1 Performance test results of each soil layer to be solidified

[0085]

[0086]

[0087] As can be seen from Table 1, the mixture obtained by treating with the soil solidifying agent of the present invention 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 were carried out on the mining road surface layers constructed in Examples 1-5 and Comparative Examples 1-7 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] Test items Compaction degree / % Deflection / 0.01mm Water seepage coefficient / % Flatness / 0.01mm Example 1 96.4 7.7 19 1.7 Example 2 96.3 7.5 19 1.9 Example 3 96.4 7.8 17 1.9 Example 4 96.2 7.4 18 1.7 Example 5 96.4 7.5 19 1.5 Comparative Example 1 96.1 6.9 11 1.1 Comparative Example 2 96.0 6.0 11 0.9 Comparative Example 3 96.0 5.9 14 0.9 Comparative Example 4 95.9 6.1 12 1.0 Comparative Example 5 96.1 5.3 9 1.0 Comparative Example 6 96.2 6.1 11 0.8 Comparative Example 7 96.2 6.7 14 1.0

[0092] It can be seen from Table 2 that the road surface treated with the soil solidifying agent of the present invention has high bearing capacity, small rebound deformation value, small water permeability coefficient, high flatness, and meets the requirements for surface paving.

[0093] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A mixed soil composition, characterized in that: The mixed soil composition comprises cement, lime soil and soil solidifier, wherein the amount of cement is 500 to 2000 parts by weight, the amount of lime soil is 10000 to 20000 parts by weight, and the amount of soil solidifier is 2 to 8 parts by weight; The raw materials of the soil solidifying agent 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. The mixed soil composition according to claim 1, characterized in that: The preparation method of the soil solidifying agent comprises the following steps: Adding sodium chloride and sodium sulfate into water, heating and stirring until well mixed, to obtain a first solution; Adding sodium stearate, sodium palmitate and benzyl alcohol to the first solution, heating and stirring until mixed, to obtain a second solution; Aluminum silicate is added to the second solution, heated and stirred until mixed, to obtain the soil solidifying agent.

3. The mixed soil composition according to claim 2, characterized in that: After adding sodium chloride and sodium sulfate into water, the heating temperature is controlled to be 30-40°C and the stirring speed is controlled to be 100-200 r / min; 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; 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.

4. Use of the mixed soil composition according to any one of claims 1 to 3 in paving a road surface.

5. A method for laying the mixed soil composition according to any one of claims 1 to 3 on a road surface, characterized in that: The laying method comprises the following steps: Spread cement and lime soil on the soil of the working surface and mix them evenly to obtain a mixed soil layer; Spraying the soil solidifying agent on the mixed soil layer and mixing evenly to obtain a soil layer to be solidified; The soil layer to be solidified is leveled and rolled.

6. The laying method according to claim 5, characterized in that: When the mixed material soil layer is obtained, the method further comprises: Remove the incompletely digested ash blocks and soil particles with a particle size of more than 5 mm. At the same time, control the measured moisture content of the soil during the mixing process to be greater than the optimal moisture content, which is 20%.

7. The laying method according to any one of claims 5 to 6, characterized in that: Before spraying the soil solidifying agent on the mixed soil layer, the process further includes diluting the soil solidifying agent, wherein the dilution multiple of the soil solidifying agent is determined based on the measured water content of the soil and the optimum water content; And / or, after spraying the soil solidifying agent on the mixed soil layer, the mixture is allowed to stand for 30 to 60 minutes and then mixed evenly.

8. The laying method according to any one of claims 5 to 6, characterized in that: The rolling comprises: First, use a 10-15t roller to perform static rolling for 1-3 times, and then use a 15-20t roller to perform strong vibration rolling for 3-5 times; The rolling speed of a 10-15t roller is 2-3km / h, and the rolling speed of a 15-20t roller is 3-4km / h; and / or, after the rolling is completed, including: The moisture content of the road surface soil is measured, and when the measured moisture content of the road surface soil is lower than the optimum moisture content, the road surface soil is replenished with water and rolled again.

Images