Foundation filling construction method for high-fill road

Abstract

The invention relates to the technical field of construction technologies, and discloses a high-fill track foundation filling construction method, which comprises the following steps: summarizing related improved soil backfilling mix proportion parameters through laboratory tests, and issuing a related improved soil backfilling mix proportion report through a laboratory; according to the filling construction method for the high-liquid-limit soil red clay improved backfill high-fill track foundation, by considering from the aspect of compaction filling, the optimal proportion of cement-doped improved red clay is 5%, it is proved that the compaction performance of the red clay can be changed by adding a certain amount of cement into the red clay, and the compaction performance of the red clay can be changed by adding 5% of cement into the red clay. The maximum dry density of the red clay can be increased from 1.1. 76 g / cm < 2 > to 1.82 g / cm < 2 >, so that the cement improves the compaction performance of the red clay, the effect is good, the liquid plasticity of the improved red clay meets the standard bearing capacity, strength and deformation requirements, outsourcing of earthwork is not needed, the red clay in the local area can be reasonably utilized, the engineering cost is reduced, and the construction efficiency is improved. And the damage to the natural environment is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of construction technology, and in particular to a high fill field road foundation filling construction method. Background Art

[0002] With the development of social economy, airports, as important infrastructure, have become increasingly necessary in cities. In recent years, a large number of new general airports have been built. However, due to the large area of ​​airports and high requirements for the surrounding environment, there are few sites suitable for direct airport construction. Some airports can only be located in areas with poor geological conditions such as mountainous areas. Airport construction is bound to involve deep excavation and high filling of earthwork, and the construction process will face this problem.

[0003] The red clay in the proposed site is the weathered residual of limestone, with the characteristics of developed cracks, hard on top and soft on the bottom, shrinkage due to water loss, and softening when exposed to water. It is distributed throughout the site, with uneven thickness and distribution, and the re-immersion characteristic category is Class I (it can return to its original position after shrinkage and re-immersion), with medium to high compressibility. Due to the large amount of excavation and backfilling of red clay, it has been tested that the red clay is a high liquid limit soil. According to Article 6.4.3 of the "Civil Airport Geotechnical Engineering Design Code" (MH / T5027-2013), this layer of red clay cannot be directly used as filler in the flight zone pavement influence zone and the fill slope stability influence zone. In order to carry out the high fill runway foundation filling construction, it is necessary to discard the excavated red clay and purchase earthwork from outside, which increases the cost very much. It can be seen that we are in urgent need of a high fill runway foundation filling construction method. Summary of the invention

[0004] In view of the above technical deficiencies, the purpose of the present invention is to provide a high liquid limit soil red clay improved backfill high fill field road foundation filling construction method, by improving the red clay (slope area, soil surface area, road trough area) backfill, the high liquid limit soil can not be used as backfill material and the need to purchase earthwork outside the problem, at the same time, the improved red clay liquid plasticity meets the standard bearing capacity, strength and deformation requirements, can reasonably use the local red clay, reduce engineering costs, reduce damage to the natural environment.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a high fill road foundation filling construction method, comprising the following steps: Construction preparation: Summarize the parameters of the improved soil backfill mix ratio through laboratory tests, and issue a report on the improved soil backfill mix ratio through the laboratory; Treatment of high fill areas: The engineering properties of the upper soil layer of the high fill area are poor, so it is treated by excavation and replacement. After the replacement of the plain soil, the surface is impact rolled, and then tested. After passing the test, the site is leveled, the surface soil is removed from the construction area, the loose soil layer on the surface is rolled, and the access roads for machinery and equipment are built to remove surface water. Drainage ditches are built around the construction area to ensure smooth drainage of the site, and the horizontal elevation of the fill surface is measured, preferably with horizontal marks to control the thickness of the fill layer; Surveying and setting out: Use a total station to encrypt and re-measure the pile position coordinates, set the middle pile every 20m, measure and set the filling control side piles in the trench area and insert the filling layer control poles at the side piles, use red paint to mark the paving thickness and width of each layer, and then hang the line for construction; Red clay and cement testing: Take samples of red clay and cement for indoor experiments, and conduct compaction tests and unconfined compressive strength tests on the mixture according to design requirements to determine the maximum dry density and optimal moisture content of the improved soil; Earthwork excavation: Use horizontal layered excavation method to obtain red clay filler with relatively consistent water content. Unload the improved red clay directly from the excavation section and spread it on the filling surface of the road-mixing operation site. Calculate the filling area of ​​each truck based on the transportation volume and loose paving thickness of the dump truck. Draw a square grid on the ground to be paved with lime powder, and unload one truck of soil in each grid; Moisture content detection: Test the moisture content of the filler to ensure that the filler is controlled within the optimum moisture content range of -3% to 2%; Cement paving: Calculate the area of ​​lime paving per truck based on the volume of the dump truck, and draw squares with lime powder on the finely leveled red clay roadbed. Unload a truckload of cement per square, and use a scraper to spread the cement evenly with manual labor; Road mixer mixing: Use a soil road mixer to mix cement and red clay, and mix at least twice to form improved soil; Leveling: First use a roller to quickly and statically press the improved soil once, then use a grader to perform fine leveling operations. For local pits, the soil is manually added and leveled in time for the local uneven areas; Rolling: After the improved soil is mixed evenly and the ash dosage is tested to be qualified, it is initially leveled by a grader and manual labor, and then rolled to the required compaction density within the full width of the roadbed by a roller. The first rolling is static rolling, the second to third times are weak vibration rolling, and from the fourth time onwards, strong vibration rolling is used until the improved soil after rolling reaches the required density. The last static rolling is done to eliminate the traces of the roller; Compactness test: Test the compactness of the improved soil to ensure that the compactness of the improved soil meets the standard; Curing: After the improved soil is compacted, if construction cannot continue, the improved soil roadbed should be cured.

[0006] Preferably, the construction preparation comprises the following steps: Test ratio confirmation: Determine the natural water content, liquid limit, plastic limit, and optimal water content of red clay; Sample preparation: 0%, 3%, 5%, 7%, and 9% cement were added to the red clay samples for 5 groups of tests. Five samples with a moisture content difference of 2.5% were prepared for each group of tests. The moisture content of the third sample was close to the optimal moisture content (the optimal moisture content is approximately equal to the plastic limit moisture content. The optimal moisture content of the red clay used in the test should be determined before the test). Water was added to the remaining samples by analogy. After adding water, the samples were mixed well and simmered for one day. Record volume and weight: Wipe the light compacting cylinder clean, weigh it, and record the volume and weight of the compacting cylinder; Compaction test: Use a light compactor to compact the sample layer by layer, and weigh the total weight of the sample and the cylinder after scraping it flat; Push out the sample; use a demoulding instrument to push out the sample, pick out an appropriate amount of sample from the middle to determine the moisture content of the sample.

[0007] Preferably, in the red clay and cement testing, the organic soil, tree roots, turf and other debris at the red clay source are first completely removed and transported to a designated waste dump, and then representative soil samples are taken at the red clay source.

[0008] Preferably, if the water content is too low in the moisture content detection step, a watering truck is used to spray water to reach an optimal water content. If the water content is too high, a bulldozer tiller or a plow is used to loosen and dry the soil to reduce the water content to the optimal water content. A roller is then used to quickly statically press the spread red clay, and then a grader is used to fine-level it. For areas with uneven surfaces and insufficient elevations, the red clay is filled with a grader or manually.

[0009] Preferably, the cement dosage in the cement paving step is calculated as follows: cement dosage (50kg) = dry density of soil × loose paving thickness of plain soil × loose paving coefficient of plain soil × cement paving area × cement dosage ratio. Ordinary cement with a strength grade of P.C32.5 (the cement physical properties of fineness, setting time, stability and strength have all been found to be qualified after testing) is mixed with red clay, and the cement dosage is 5% (by weight).

[0010] Preferably, when mixing cement and red clay in the mixing step of the road mixer, the soil lumps are broken up and the particle size thereof is not greater than 15 mm. The road mixer should enter the lower supporting layer 2 cm during the second mixing, and check the water content of the improved soil after mixing. If the water content is insufficient, water is added by sprinkling, and the mixture is mixed again to make the water content of the improved soil within -3% to 2% of the optimum water content.

[0011] Preferably, the maximum rolling speed of the roller in the rolling step is no more than 4 km / h, and one forward and one backward rolling is the full width of the rolling.

[0012] Preferably, during the rolling step, the longitudinal lap length is not less than 2m, the longitudinal track overlap between rows is not less than 40cm, and the upper and lower layers of filling joints should be staggered by not less than 3m.

[0013] Preferably, in the curing step, the surface of the improved soil is kept moisturized for no less than 7 days.

[0014] Compared with the prior art, the beneficial effects achieved by the present invention are: The present invention considers the compaction and filling aspect and finds that the optimal ratio of cement-added red clay is 5%, which also proves that adding a certain amount of cement into red clay can change the compaction performance of red clay, and cement can improve the filling performance of red clay. When 5% cement is added into red clay, the maximum dry density of red clay can be increased from 1.1.76 g / cm² to 1.82 g / cm². It can be seen that the compaction performance of cement-improved red clay is good, and the liquid plasticity of the improved red clay meets the standard bearing capacity, strength and deformation requirements, and there is no need to purchase earthwork, so that the red clay in the area can be reasonably utilized, thereby reducing the engineering cost and reducing the damage to the natural environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a curve diagram of compaction test data of the present invention; Figure 2 It is a flowchart of the overall process steps of the present invention; DETAILED DESCRIPTION

[0016] The specific implementation modes of the present invention will be further described in detail below with reference to the accompanying drawings. The following is a specific implementation method of a high fill road foundation filling construction method.

[0018] See also Figure 1-2 A high fill road foundation filling construction method comprises the following steps: 1. Construction preparation: Summarize the relevant improved soil backfill mix ratio parameters through laboratory tests, and issue the relevant improved soil backfill mix ratio report through the laboratory; Construction preparation includes the following steps: Test ratio confirmation: Determine the natural water content, liquid limit, plastic limit, and optimal water content of red clay; Sample preparation: 0%, 3%, 5%, 7%, and 9% cement were added to the red clay samples for 5 groups of tests. Five samples with a moisture content difference of 2.5% were prepared for each group of tests. The moisture content of the third sample was close to the optimal moisture content (the optimal moisture content is approximately equal to the plastic limit moisture content. The optimal moisture content of the red clay used in the test should be determined before the test). Water was added to the remaining samples by analogy. After adding water, the samples were mixed well and simmered for one day. Record volume and weight: Wipe the light compacting cylinder clean, weigh it, and record the volume and weight of the compacting cylinder; Compaction test: Use a light compactor to compact the sample layer by layer, and weigh the total weight of the sample and the cylinder after scraping it flat; Push out the sample; use a demoulding instrument to push out the sample, and pick out an appropriate amount of sample from the middle to measure the moisture content of the sample; Reference Figure 1The moisture content of the sample can be directly measured through the compaction test. The density can be obtained by dividing the mass by the density. The dry density of the sample can be obtained according to the moisture content and density. The relationship curve between dry density and moisture content is drawn with dry density as the ordinate and moisture content as the abscissa. The ordinate and abscissa of the peak point on the curve represent the maximum dry density and the optimal moisture content of the compacted sample. When the red clay is not mixed with cement, the relationship curve between the dry density and moisture content of the sample shows that at the top of the curve, the maximum dry density of the red clay is 1.76g / cm³, and the optimal moisture content corresponding to the maximum dry density is 17.2%. It can be seen that the maximum dry density of the red clay is not large at this time, and the optimal moisture content of the red clay is relatively high, which is related to the high compressibility and high liquid limit characteristics of the red clay. Recently, when the cement content is 5%, the maximum dry density is 1.82g / cm³, and the corresponding optimal moisture content is 16.2%. Therefore, when 5% lime is added to red clay, the maximum dry density of red clay is greater than that of 3% cement, but the optimal moisture content does not decrease. When the cement content is 7%, the relationship curve between dry density and moisture content shows that the maximum dry density of the mixed sample is 1.76g / cm³, and the corresponding optimal moisture content is 11.5%. Therefore, when 7% lime is added to red clay, the maximum dry density is less than that of 5% cement, and the maximum dry density does not increase with the increase of cement content. In other words, using cement to improve red clay, adding too much cement cannot improve the filling performance of red clay. When the water content is When the mud content is 9%, the relationship curve between dry density and moisture content shows that the maximum dry density of the mixed sample is 1.78g / cm³, and the corresponding optimal moisture content is 16.5%. It can be seen that when 9% cement is added to the red clay, the maximum dry density is not much different from that of 7% cement, and is smaller than that of 5% cement. This proves again that excessive addition of cement cannot improve the filling performance of red clay. In summary, the maximum dry densities of the samples with cement content of 0%, 3%, 5%, 7%, and 9% are 1.76g / cm³, 1.80g / cm³, 1.82g / em³, 1.76g / cm³, and 1.78g / em³, respectively, and the corresponding optimal moisture contents are 17.2%, 14.6%, and 15.9%, respectively. .8%, 16.2%, 11.5%, 16.5%. From these data, the maximum dry density does not increase with the increase of water mixing amount. When the cement content is 5%, the maximum dry density is the largest. The optimum moisture content does not show regularity with the change of cement content. Therefore, from the perspective of compaction and filling, the best ratio of cement to improve red clay is 5%, which also proves that adding a certain amount of cement to red clay can change the compaction performance of red clay, but it is not the case that the more cement is added, the better the improvement effect. The cement content of 5% is the best ratio. Therefore, cement can improve the filling performance of red clay. When 5% cement is added to red clay, the maximum dry density of red clay can be increased from 1.1.76g / cm² to 1.82g / cm², which shows that the compaction performance of cement-improved red clay is good.

[0019] 2. Treatment of high fill areas: The engineering properties of the upper soil layer in high fill areas are poor, so excavation and replacement are adopted for treatment. After replacement with bare soil, the surface is impact compacted and tested after compaction. After passing the test, the site is leveled, the topsoil is removed from the area to be constructed, the loose soil layer is compacted, access roads for machinery and equipment are built, surface water is removed, drainage ditches are built around the construction area to ensure smooth drainage of the site, the horizontal elevation of the fill surface is measured, and horizontal marks are preferably made to control the thickness of the fill layers.

[0020] 3. Surveying and laying out: Use a total station to encrypt and re-measure the pile position coordinates, set the center pile every 20m, measure and set the filling control side piles in the trench area and insert the filling layer control poles at the side piles, use red paint to mark the paving thickness and width of each layer, and carry out line construction.

[0021] 4. Red clay and cement testing: Take samples of red clay and cement for indoor experiments, and carry out compaction tests and unconfined compressive strength tests on the mixture according to the design requirements to determine the maximum dry density and optimal moisture content of the improved soil; For red clay and cement testing, firstly, the organic soil, tree roots, grass and other debris at the red clay source should be completely removed and transported to the designated waste dump, and then representative soil samples should be taken at the red clay source; By taking representative soil samples at the red clay source and then conducting experiments on red clay and cement according to the design requirements of the construction preparation stage, the maximum dry density and optimal moisture content of the improved soil at the construction site are ensured.

[0022] 5. Earth excavation: Use horizontal layered excavation method to obtain red clay filler with relatively consistent water content. Unload the improved red clay directly from the excavation section and spread it on the filling surface of the road mixing operation site. Calculate the filling area of ​​each truck based on the transportation volume and loose paving thickness of the dump truck. Draw a square grid on the ground to be paved with lime powder, and unload one truck of soil in each grid.

[0023] 6. Moisture content detection: Detect the moisture content of the filler to ensure that the filler is controlled within the optimum moisture content of -3% to 2%; If the moisture content is too low during the moisture content detection step, a sprinkler truck is used to spray water to reach the optimal moisture content. If the moisture content is too high, a bulldozer tiller or a plow is used to loosen and dry the soil to reduce the moisture content to the optimal moisture content. A roller is then used to quickly statically press the spread red clay, and then a grader is used to fine-level it. For areas with uneven surfaces and insufficient elevations, the red clay is filled with a grader or manually.

[0024] 7. Cement paving: Calculate the area of ​​lime paving per truck according to the volume of dump trucks, and draw squares with lime powder on the finely leveled red clay roadbed. Unload a truckload of cement per square, and use a scraper to spread the cement evenly with manual labor; The cement dosage in the cement paving step is calculated as follows: cement dosage (50kg) = dry density of soil × loose paving thickness of plain soil × loose paving coefficient of plain soil × cement paving area × cement dosage ratio. Ordinary cement with strength grade P.C32.5 (the cement physical properties of fineness, setting time, stability and strength have all been tested to be qualified) is mixed with red clay, and the cement dosage is 5% (weight percentage).

[0025] 8. Mixing with road mixer: Use soil road mixer to mix cement and red clay, mix at least twice to form improved soil; When mixing cement and red clay in the mixing step of the road mixer, the soil lumps are broken up and their particle size is not greater than 15mm. The road mixer should enter the lower supporting layer 2cm during the second mixing and check the moisture content of the improved soil after mixing. If its moisture content is insufficient, sprinkle water to supplement it and mix it again so that the moisture content of the improved soil is within -3% to 2% of the optimal moisture content.

[0026] 9. Leveling: First use a roller to quickly and statically compact the improved soil once, and then use a grader to perform fine leveling operations. For local potholes, lack of soil and uneven areas, manually add improved soil and flatten them in time.

[0027] 10. Rolling: After the improved soil is mixed evenly and the ash dosage is tested to be qualified, it is initially leveled by a grader and manual labor, and then rolled to the required compaction density within the full width of the roadbed by a roller. The first rolling is static rolling, the 2nd to 3rd rolling is weak vibration rolling, and from the fourth time onwards, strong vibration rolling is used until the improved soil after rolling reaches the required density. The last static rolling is done to eliminate the traces of the roller. The maximum rolling speed of the roller in the rolling step is not more than 4km / h, and one forward and backward rolling is considered one rolling. When rolling in the rolling step, the longitudinal lap length is not less than 2m, the longitudinal track overlap between rows is not less than 40cm, and the upper and lower layers of filling joints should be staggered by not less than 3m.

[0028] Compactness test: Test the compactness of the improved soil to ensure that the compactness of the improved soil meets the standard; By testing the compaction degree of red clay, it is ensured that the liquid plasticity of red clay meets the standard requirements of bearing capacity, strength and deformation.

[0029] 12. Curing: After the improved soil is compacted, if construction cannot continue, the improved soil roadbed should be cured.

[0030] In the curing step, the surface of the improved soil is kept moisturized for no less than 7 days, and steps 3 to 10 are repeated to achieve layered filling of the improved soil roadbed.

[0031] Through the above-mentioned construction method, the red clay is improved. The liquid plasticity of the improved red clay meets the standard requirements of bearing capacity, strength and deformation. There is no need to purchase earthwork from outside, so that the red clay in the area can be reasonably utilized, achieving the effect of reducing project costs and reducing damage to the natural environment.

[0032] Although specific embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit thereof, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high fill field foundation construction method, characterized in that: The following steps are involved: Construction preparation: Summarize the parameters of the improved soil backfill mix ratio through laboratory tests, and issue a report on the improved soil backfill mix ratio through the laboratory; Treatment of high fill areas: The engineering properties of the upper soil layer of the high fill area are poor, so it is treated by excavation and replacement. After the replacement of the plain soil, the surface is impact rolled, and then tested. After passing the test, the site is leveled, the surface soil is removed from the construction area, the loose soil layer on the surface is rolled, and the access roads for machinery and equipment are built to remove surface water. Drainage ditches are built around the construction area to ensure smooth drainage of the site, and the horizontal elevation of the fill surface is measured, preferably with horizontal marks to control the thickness of the fill layer; Surveying and setting out: Use a total station to encrypt and re-measure the pile position coordinates, set the middle pile every 20m, measure and set the filling control side piles in the trench area and insert the filling layer control poles at the side piles, use red paint to mark the paving thickness and width of each layer, and then hang the line for construction; Red clay and cement testing: Take samples of red clay and cement for indoor experiments, and conduct compaction tests and unconfined compressive strength tests on the mixture according to design requirements to determine the maximum dry density and optimal moisture content of the improved soil; Earthwork excavation: Use horizontal layered excavation method to obtain red clay filler with relatively consistent water content. Unload the improved red clay directly from the excavation section and spread it on the filling surface of the road-mixing operation site. Calculate the filling area of ​​each truck based on the transportation volume and loose paving thickness of the dump truck. Draw a square grid on the ground to be paved with lime powder, and unload one truck of soil in each grid; Moisture content detection: Test the moisture content of the filler to ensure that the filler is controlled within the optimum moisture content range of -3% to 2%; Cement paving: Calculate the area of ​​lime paving per truck based on the volume of the dump truck, and draw squares with lime powder on the finely leveled red clay roadbed. Unload a truckload of cement per square, and use a scraper to spread the cement evenly with manual labor; Road mixer mixing: Use a soil road mixer to mix cement and red clay, and mix at least twice to form improved soil; Leveling: First use a roller to quickly and statically press the improved soil once, then use a grader to perform fine leveling operations. For local pits, the soil is manually added and leveled in time for the local uneven areas; Rolling: After the improved soil is mixed evenly and the ash dosage is tested to be qualified, it is initially leveled by a grader and manual labor, and then rolled to the required compaction density within the full width of the roadbed by a roller. The first rolling is static rolling, the second to third times are weak vibration rolling, and from the fourth time onwards, strong vibration rolling is used until the improved soil after rolling reaches the required density. The last static rolling is done to eliminate the traces of the roller; Compactness test: Test the compactness of the improved soil to ensure that the compactness of the improved soil meets the standard; Curing: After the improved soil is compacted, if construction cannot continue, the improved soil roadbed should be cured.

2. A high fill field road foundation filling construction method according to claim 1, characterized in that: Construction preparation includes the following steps: Test ratio confirmation: Determine the natural water content, liquid limit, plastic limit, and optimal water content of red clay; Sample preparation: 0%, 3%, 5%, 7%, and 9% cement were added to the red clay samples for 5 groups of tests. Five samples with a moisture content difference of 2.5% were prepared for each group of tests. The moisture content of the third sample was close to the optimal moisture content (the optimal moisture content is approximately equal to the plastic limit moisture content. The optimal moisture content of the red clay used in the test should be determined before the test). Water was added to the remaining samples by analogy. After adding water, the samples were mixed well and simmered for one day. Record volume and weight: Wipe the light compacting cylinder clean, weigh it, and record the volume and weight of the compacting cylinder; Compaction test: Use a light compactor to compact the sample layer by layer, and weigh the total weight of the sample and the cylinder after scraping it flat; Push out the sample; use a demoulding instrument to push out the sample, pick out an appropriate amount of sample from the middle to determine the moisture content of the sample.

3. A high fill road foundation filling construction method according to claim 1, characterized in that: For red clay and cement testing, the organic soil, tree roots, turf and other debris at the red clay source should be completely removed and transported to the designated waste dump, and then representative soil samples should be taken at the red clay source.

4. A high fill road foundation construction method according to claim 1, characterized in that: If the moisture content is too low during the moisture content detection step, a sprinkler truck is used to spray water to reach the optimal moisture content. If the moisture content is too high, a bulldozer tiller or a plow is used to loosen and dry the soil to reduce the moisture content to the optimal moisture content. A roller is then used to quickly statically press the spread red clay, and then a grader is used to fine-level it. For areas with uneven surfaces and insufficient elevations, the red clay is filled with a grader or manually.

5. A high fill road foundation construction method according to claim 1, characterized in that: The cement dosage in the cement paving step is calculated as follows: cement dosage (50kg) = dry density of soil × loose paving thickness of plain soil × loose paving coefficient of plain soil × cement paving area × cement dosage ratio. Ordinary cement with strength grade P.C32.5 (the cement physical properties of fineness, setting time, stability and strength have all been tested to be qualified) is mixed with red clay, and the cement dosage is 5% (weight percentage).

6. A high fill road foundation construction method according to claim 1, characterized in that: When mixing cement and red clay in the mixing step of the road mixer, the soil lumps are broken up and their particle size is not greater than 15mm. The road mixer should enter the lower supporting layer 2cm during the second mixing and check the moisture content of the improved soil after mixing. If its moisture content is insufficient, sprinkle water to supplement it and mix it again so that the moisture content of the improved soil is within -3% to 2% of the optimal moisture content.

7. A high fill road foundation construction method according to claim 1, characterized in that: The maximum rolling speed of the roller in the rolling step is not more than 4km / h, and one forward and one backward rolling is considered one rolling.

8. A high fill road foundation construction method according to claim 1, characterized in that: During the rolling step, the longitudinal lap length shall be no less than 2m, the longitudinal overlap between rows shall be no less than 40cm, and the joints between the upper and lower layers of filling shall be staggered by no less than 3m.

9. A high fill road foundation construction method according to claim 1, characterized in that: During the curing step, the surface of the improved soil should be kept moisturized for no less than 7 days.

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