Construction method of maca sand filling material roadbed

Abstract

The invention discloses a maca sand filling material roadbed construction method, which comprises the following steps of: adopting a line production construction mode of excavating and loading by an excavator, transporting by a dump truck, manually matching with a bulldozer, leveling by a land leveler, rolling by a vibratory roller and detecting the compaction quality by a density method in the whole filling construction process, and sorting and removing maca sand according to the particle size and components of the maca sand in a material taking field. Grading optimization treatment is carried out, organic soil, tree roots, turf and other sundries in the yard are thoroughly removed and then transported to a designated waste slag yard, the whole large maca sand roadbed filler generally does not exceed 2 / 3 of the paving and filling thickness, and the whole large maca sand roadbed filler is transported to an area which is convenient to use and does not affect construction to be classified and stacked; when the maca sand is applied to highway roadbed filling, the requirements of roadbed construction on the strength and stability of a filling material can be met, the service life of a pavement is prolonged, the utilization rate of land resources can be increased, land resource conservation and intensification are enhanced, land resources are practically protected, and the dependence of highway roadbed filling on earthwork resources is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of highway embankment construction, and particularly relates to a construction method for a roadbed filled with magu sand. Background Art

[0002] As the bottom structure of highway engineering, the roadbed is the foundation of the entire road surface, bearing the traffic load transmitted from the road surface. The quality of the roadbed is directly related to the service quality of the entire highway. It is not uncommon for the road surface to fail to reach the designed service life due to roadbed problems and show early damage; therefore, ensuring the strength and stability of the roadbed is the top priority in highway construction.

[0003] With the development of infrastructure construction, a large amount of earthwork resources are required for highway embankments. Due to its advantages such as convenient excavation, local selection, easy compaction, and effective reduction of transportation costs, earthwork is the most widely used roadbed filling material in plain areas; if roadbed filling only relies on local earthwork resources, it will not only cause a large waste of high-quality resources, resulting in a shortage of land resources, but also have a certain impact on the cultivated land area, generating a large number of social problems.

[0004] Facing the contradiction between the large consumption of earthwork required for highway construction and the shortage of land resources, it is necessary to strengthen the conservation and intensive use of land resources during traffic infrastructure construction, effectively protect land resources, and improve land resource utilization. Therefore, while constructing highways, it is urgent to seek a new material and new technology for roadbed filling.

[0005] Magu sand is widely distributed in the mountainous areas of the Funiu Mountain system in western Henan and the remaining veins of the Tongbai Mountains. It is strongly weathered granite particles, with a sandy yellow and grayish white appearance. The bonding performance between magu sand particles is weak, and the particles can be easily separated. Magu sand particles are harder, more resistant to wind and rain erosion, and have greater water absorption than ordinary soil. Applying magu sand to highway roadbed filling can not only meet the requirements of roadbed construction for the strength and stability of filling materials, reduce the dependence of highway embankments on earthwork resources, but also effectively solve the problem of shortage of roadbed filling materials. Summary of the Invention

[0006] The purpose of the present invention is to provide a construction method for a roadbed filled with magu sand to solve the problems raised in the above background art.

[0007] To achieve the above purpose, the present invention provides the following technical solution: A construction method for a roadbed filled with magu sand, including the following steps:

[0008] S1 Foundation treatment

[0009] After removing the sundries within the subgrade construction area with the assistance of manual labor and bulldozers, level the original ground with a grader, and compact the original ground with a vibratory roller before filling the subgrade. Compaction degree should reach over 90% before proceeding with subgrade filling construction;

[0010] S2 Subbase Course Construction

[0011] After the foundation treatment is completed, set up a subbase course for the macadam subgrade before filling the macadam. The materials for the subbase course are a 50-cm-thick clay, soil-cement, and polypropylene filament needle-punched geotextile subbase course. The first layer of macadam material on the subbase course is paved in full width; when using grass planting protection or comprehensive protection with framework plants, cover the slope surface with 30 cm of planting soil;

[0012] S3 Construction Layout

[0013] Before filling the macadam subgrade on the subbase course working surface that has passed the acceptance, conduct survey layout, lay out the center pile and left and right side piles of the road, measure the actual elevation, calculate the designed width of the subgrade, then widen 0.5 meters on both sides according to the designed width, mark the filling construction side piles, and then use lime to mark square grids along the longitudinal and transverse directions of the road surface. The specific width is determined according to the loading capacity of each vehicle and the paving thickness, and unload one vehicle of macadam for each grid;

[0014] S4 Layered Filling

[0015] S5 Paving and Levelling

[0016] Use a bulldozer to pave the soil, with manual labor for assistance. During paving, manually clean the sundries in the filler and stack them in a designated area outside the subgrade to ensure that the maximum particle size of the filler is not greater than 10 cm. First, use manual labor in cooperation with the bulldozer to initially level from both sides of the subgrade to the middle along the subgrade direction, then use the bulldozer to stabilize for 1 - 2 passes. During mechanical leveling, on-site inspectors should use a ruler to measure the loose paving thickness at any time. If it does not meet the thickness requirements, it must be leveled again until the required loose paving thickness is reached, and make the construction surface of the embankment into a 2% double-sided cross slope for subgrade drainage;

[0017] S6 Sunning

[0018] S7 Control of Filler Moisture Content

[0019] After each paving of macadam, on-site testers conduct moisture content detection on the paved macadam filler. If the moisture content of the compacted macadam is not within the range of the optimum moisture content ±2%, sprinkle water; the water sprinkling is carried out in two times. The first water sprinkling is 60% - 70% of the required water volume. After the subgrade surface dries and does not stick to the wheel, roll it for 2 - 3 passes. The second water sprinkling volume is 30% - 40% of the required water volume. After the subgrade surface dries and does not stick to the wheel, roll it quickly. If the moisture content exceeds the optimum moisture content by 2%, conduct sunning until it is within 2% of the optimum moisture content and roll it quickly;

[0020] S8 Subgrade Rolling

[0021] After the material is pushed and initially leveled by a bulldozer, the bulldozer is used to perform a stabilizing roll for 1 - 2 passes, and the grader is used for fine leveling for 1 - 2 passes to ensure a cross slope of 2% for the road crown. Then, a 20T vibratory roller is used for a light vibration for 1 pass followed by a heavy vibration for 3 passes. Finally, the roller is used for a static roll for 1 - 2 passes. During the vibratory rolling, pay attention to the rolling speed increasing from slow to fast and the vibration intensity increasing from weak to strong. The compaction routes are longitudinally parallel to each other. In the straight section, roll from both sides towards the center of the subgrade. In the curved section, roll from the inner side of the curve towards the outer side. The transverse joints should overlap, and there should be a longitudinal overlap between the adjacent two sections before and after;

[0022] The rolling speed of the roller is controlled at 30 - 70 m / min, the frequency is 25 - 35 Hz, and the amplitude is not less than 2 mm. During rolling, it is carried out longitudinally in a forward and backward manner from both sides to the middle, with a transverse rolling wheel overlap of 30 - 50 cm. During rolling, ensure that there is no missed rolling, no dead corners, uniform compaction, no soft springing or peeling on the subgrade surface, the subgrade surface is flat, the side lines are straight, and the edges are stable without slope deficiency;

[0023] S9 Compaction Degree Detection

[0024] Ensure that the compaction equipment and testing equipment are in good condition, ensure that the materials to be tested meet the design requirements, select representative test points according to the specifications, perform compaction operations according to the design requirements, record the compaction times and speed parameters, use a nuclear density gauge or sand cone method for preliminary compaction degree detection, record the data, take samples from the site to ensure that the samples are representative, use laboratory equipment to measure the maximum dry density and actual dry density of the samples. After passing, continue construction. If not qualified, repeat the mechanical rolling;

[0025] S10 Road Surface Shaping

[0026] Remove the sundries, loose materials and obstacles on the road surface, ensure that the base layer is flat and dense and meets the design requirements, prepare the shaping equipment and measuring tools, use a level or laser screed to measure the road surface elevation, determine the shaping thickness, use a grader or scraper to perform preliminary shaping on the road surface, adjust the road surface elevation and slope, and perform fine adjustment according to the measurement data to ensure that the road surface flatness and slope meet the design requirements;

[0027] S11 Inspection and Acceptance.

[0028] Preferably, before construction, check the performance of the construction equipment and the supporting conditions and performance of the auxiliary construction vehicles to ensure that all equipment works normally before construction.

[0029] Preferably, the filling material of crushed bone sand meets the requirements of CBR and maximum particle size for the rock - filled subgrade.

[0030] Preferably, the settlement after rolling should tend to be stable, with the average settlement of the last two passes not exceeding 3 mm, or the average settlement being 5% - 10% of the total settlement.

[0031] Preferably, the lofting structure includes a base. Nuts are symmetrically and fixedly connected to the surface of the base. Fixed screws are screwed inside the inner walls of the two nuts. The lower ends of the fixed screws are in the shape of a needle tip. The fixed screws penetrate through the base. A through groove is formed in the middle of the surface of the base. Two support plates are symmetrically assembled on both sides of the surface of the base. The two support plates are located on both sides of the through groove. A slide rail is fixedly assembled between the two support plates. Two sliders are slidably sleeved on the outer wall of the slide rail. Cross plates are fixedly assembled on the side walls of the two sliders. Hydraulic cylinders are fixedly assembled inside the inner walls of the two cross plates. Drill bits are fixedly assembled at the ends of the piston rods of the two hydraulic cylinders.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] (1) Save earthwork and conserve land resources;

[0034] (2) The bonding force between the magu sand particles is small. Large magu sand can be broken without increasing the power of the compaction machinery. Moreover, the magu sand is easy to compact, reducing the compaction times of the roller, improving the construction efficiency, and reducing the idle costs of machinery and personnel;

[0035] (3) The post-construction settlement of the magu sand subgrade filling material is small. An interlocking skeleton structure is formed between the particles. Soil particles fill the voids of the magu sand skeleton, making the magu sand subgrade form a skeleton-dense structure. This structure has a large internal friction angle and cohesion, greatly improving the strength and stability of the magu sand subgrade, and reducing the risk of post-construction rework and the overhaul costs caused by uneven settlement of the subgrade during the operation period;

[0036] (4) Compared with the traditional filled soil subgrade, the magu sand subgrade is harder and more resistant to wind and rain erosion, reducing the probability of the subgrade being damaged by water, extending the overall service life of the highway, reducing the maintenance and repair costs, and reducing the life cycle cost;

[0037] Applying magu sand to the filling of the expressway subgrade can not only meet the requirements of the subgrade construction for the strength and stability of the filling material, extend the service life of the road surface, but also improve the utilization rate of land resources, strengthen the conservation and intensive use of land resources, effectively protect land resources, and reduce the dependence of the expressway embankment on earthwork resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the implementation of a specific embodiment of this construction method;

[0039] Figure 2 It is a three-dimensional schematic diagram of the lofting structure;

[0040] Figure 3 It is a front view of the lofting structure.

[0041] 1 - Lofting structure, 11 - Base, 12 - Drill bit, 13 - Nut, 14 - Fixed screw, 15 - Support plate, 16 - Slide rail, 17 - Slide block, 18 - Cross plate, 19 - Hydraulic cylinder Specific implementation manner

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0043] Please refer to Figures 1 - 3 , the present invention provides a construction method for a roadbed of magmatic sand filling material. The entire filling construction process adopts a flow operation construction method of excavator loading, self - unloading truck transportation, manual cooperation with a bulldozer, grader leveling, vibratory roller compaction, and density method for detecting compaction quality. Sorting and removing are carried out according to the particle size and composition of magmatic sand in the material yard, and gradation optimization treatment is carried out. Organic soil, tree roots, turf and other sundries in the yard are completely removed and transported to the designated waste dump. Generally, a large piece of magmatic sand roadbed filler does not exceed 2 / 3 of the paving thickness and is transported to an area convenient for utilization and without affecting construction for classified stacking; Subsequently, relevant tests are carried out by the laboratory, and the test results of various raw materials are reviewed and approved by the supervision engineer as the basis for the construction of the test section;

[0044] S1 Foundation treatment

[0045] After manually cooperating with a bulldozer to remove grass, humus soil, tree roots and other sundries within the roadbed construction range, the original ground is leveled with a grader, and the original ground is pre - compacted with a vibratory roller. When the compaction degree reaches more than 90%, roadbed filling construction is carried out;

[0046] S2 Sub - seal layer construction

[0047] After the foundation treatment is completed, a sub - seal layer of the roadbed is set before the magmatic sand roadbed filling. The material of the sub - seal layer can adopt a 50 - cm - thick clay, soil - cement (cement mass incorporation ratio is 10%) and polypropylene filament needle - punched geotextile sub - seal layer. The first layer of magmatic sand material on the seal layer should be paved in full width; When grass planting protection or comprehensive protection of skeleton plants is adopted, the slope surface should be covered with a 30 - cm - thick planting soil;

[0048] S3 Construction lofting

[0049] Before filling the subgrade with macadam sand on the accepted and qualified lower seal layer working surface, conduct survey and setting out, mark the center pile and left and right side piles of the road, measure the actual elevation, calculate the designed width of the subgrade, then widen both sides by 0.5 m according to the designed width, mark the filling construction side piles, and then use lime to mark square grids along the longitudinal and transverse directions of the road surface. The specific width is determined according to the loading capacity of each vehicle and the paving thickness, and one vehicle of macadam sand is unloaded in each grid.

[0050] S4 Layered filling

[0051] S5 Paving and leveling

[0052] Use a bulldozer to pave the soil, with manual assistance. During paving, manually clean up sundries such as tree branches and grass roots in the filler and stack them centrally at a designated place outside the subgrade to ensure that the maximum particle size of the filler does not exceed 10 cm. First, manually cooperate with the bulldozer to initially level from both sides of the subgrade to the middle along the subgrade direction, and then use the bulldozer to stabilize for 1 - 2 passes. During mechanical leveling, on-site inspectors should use a ruler to measure the loose paving thickness at any time. If it does not meet the thickness requirements, it must be leveled again until the required loose paving thickness is reached, and make the construction surface of the embankment into a 2% double-sided cross slope for subgrade drainage.

[0053] S6 Sunning

[0054] S7 Control of filler moisture content

[0055] The interior of large macadam sand is mainly composed of sand grains with a diameter of less than 1 cm and various metal mineral components mainly composed of black iron powder. The sand grains are aggregated and adhered to form a continuous stone, which is hard and stable as a whole, but macadam sand has a large water absorption. Therefore, controlling the moisture content of macadam sand is the key to the success of compaction.

[0056] After each paving of macadam sand, on-site testers should detect the moisture content of the paved macadam sand filler. If the moisture content of the compacted macadam sand is not within the range of the optimum moisture content ±2%, watering should be carried out. The watering is carried out in two times. The first watering is 60% - 70% of the required water volume (generally slightly larger than the theoretical value, adjusted according to the on-site temperature). After the subgrade surface dries and does not stick to the wheels, roll for 2 - 3 passes. The second watering volume is about 30% - 40% of the required water volume. After the subgrade surface dries and does not stick to the wheels, quickly roll. If the moisture content exceeds the optimum moisture content by 2%, sunning should be carried out until it is within 2% of the optimum moisture content and quickly roll.

[0057] S8 Subgrade rolling

[0058] During the construction of macadam sand subgrade, great attention must be paid to the compaction process. Only by strictly controlling the subgrade compaction construction and providing sufficient compaction work can large macadam sand be broken, the particle size be reduced, the particles be rearranged, the pores be filled, and the void ratio be reduced, thereby improving the overall strength and deformation stability of the subgrade.

[0059] However, it should also be noted that the compaction work should be controlled within a reasonable range, ensuring sufficient compaction while avoiding excessive compaction energy that may cause the particle size to be rolled too small to achieve continuous grading. At the same time, avoid the occurrence of particle size rebound and insufficient compaction of the filler;

[0060] After the material is initially leveled by a bulldozer, the bulldozer is used to stabilize it for 1 - 2 passes, and the grader is used to finish leveling it for 1 - 2 passes to ensure a 2% cross slope of the road crown. Then, a 20T vibratory roller is used to lightly vibrate for 1 pass and then strongly vibrate for 3 passes, and finally the roller is used for static compaction for 1 - 2 passes. During vibratory compaction, pay attention to the rolling speed increasing from slow to fast and from weak vibration to strong vibration. The compaction route is longitudinally parallel. In straight sections, it is rolled from both sides towards the center of the roadbed, and in curved sections, it is rolled from the inside of the curve towards the outside. The transverse joints should overlap, and there should be longitudinal overlap between adjacent sections before and after;

[0061] The rolling speed of the roller is controlled at 30 - 70 m / min, the appropriate frequency is 25 - 35 Hz, and the amplitude is not less than 2 mm. During rolling, it is carried out longitudinally from both sides towards the middle in a progressive manner. The transverse rolling wheels overlap by 30 - 50 cm. During rolling, ensure that there is no missed compaction, no dead corners, uniform compaction, no soft springing or peeling on the roadbed surface, the roadbed surface is flat, the side lines are straight, and the edges are stable without slope deficiency;

[0062] S9 Compaction Degree Detection

[0063] Ensure that the compaction equipment (such as rollers, vibrating plates, etc.) and testing equipment (such as nuclear density gauges, sand cone methods, etc.) are in good condition, ensure that the materials to be tested meet the design requirements, select representative testing points according to the specifications, carry out compaction operations according to the design requirements, record parameters such as compaction times and speeds, use a nuclear density gauge or sand cone method for preliminary compaction degree detection, record the data, take samples from the site to ensure the samples are representative, use laboratory equipment (such as oven drying method, pycnometer method, etc.) to determine the maximum dry density and actual dry density of the samples. If qualified, continue construction; if unqualified, repeat mechanical rolling;

[0064] S10 Road Surface Shaping

[0065] Remove debris, loose materials, and obstacles on the road surface, ensure that the base layer (such as the roadbed or subbase) is flat and dense and meets the design requirements, prepare the shaping equipment and measuring tools, use a level or laser screed to measure the road surface elevation, determine the shaping thickness, use a grader or scraper to conduct preliminary shaping of the road surface, adjust the road surface elevation and slope, and make fine adjustments according to the measurement data to ensure that the road surface flatness and slope meet the design requirements;

[0066] S11 Inspection and Acceptance.

[0067] Before construction, the performance of construction equipment, the supporting conditions and performance of auxiliary construction vehicles, etc. shall be inspected to ensure that all equipment works properly before construction.

[0068] The filling material of magu sand shall meet the requirements of CBR and maximum particle size of the rock-filled subgrade.

[0069] The settlement after rolling should tend to be stable. Generally, the average settlement of the last two passes should not exceed 3 mm, or its average settlement is 5% - 10% of the total settlement.

[0070] The lofting structure 1 includes a base 11. Nuts 13 are symmetrically fixedly connected to the surface of the base 11. Fixing screws 14 are screwed inside the inner walls of the two nuts 13. The lower end of the fixing screw 14 is set to be needle-shaped. The fixing screw penetrates through the base 11. A through groove is opened in the middle of the surface of the base 11. Two support plates 15 are symmetrically assembled on both sides of the surface of the base 11. The two support plates 15 are located on both sides of the through groove. A slide rail 16 is fixedly assembled between the two support plates 15. Two sliders 17 are slidably sleeved on the outer wall of the slide rail 16. Cross plates 18 are fixedly assembled on the side walls of the two sliders 17. Hydraulic cylinders 19 are fixedly assembled inside the inner walls of the two cross plates 18. Drill bits 12 are fixedly assembled at the ends of the piston rods of the two hydraulic cylinders 19.

[0071] When the lofting structure 1 needs to be used, first rotate the fixing screws 14 on both sides, insert the needle-shaped end into the road surface to be lofted and measured, and fix the base 11. At this time, adjust the position to be lofted and measured, adjust the displacement of the slider 17 on the slide rail 16. After reaching the appropriate position, turn on the hydraulic cylinder 19. The hydraulic cylinder 19 controls the piston rod to displace downward and drives the drill bit 12 to insert into the ground until it touches the hard position at the bottom of the ground, then stop inserting. At this time, retract the piston rod and the drill bit 12, and measure the hole depth in the drilled hole. The support plate 15 ensures the stability of the equipment during use, and the cross plate 18 ensures the stability of the hydraulic cylinder 19.

[0072] Adopting a construction process similar to that of the construction of the subgrade filled with construction waste, it has strong operability, perfect technology, simple process, can meet the construction specifications and design requirements, has sufficient material sources, reduces the dependence of the embankment subgrade of the expressway on earthwork resources and construction costs, effectively solves the problem of shortage of filling materials, greatly shortens the construction period. The bonding performance between magu sand particles is weak and it is easy to separate under the action of the roller, reducing the void ratio between magu sand particles and improving the compaction degree of the subgrade. The filling material of the magu sand subgrade has properties such as large density, hard texture, not easy to weather, wear-resistant, good stability, clean sand quality, resistant to wind and rain erosion, no mud and other harmful impurities, and stable chemical properties. Applying it to the embankment subgrade can reduce the settlement of the subgrade and improve the stability and strength of the subgrade.

[0073] Embodiment

[0074] Magu sand particles are bonded to each other in a natural state to form a large piece of Magu sand. Since the bonding between Magu sand particles is not strong, the Magu sand particles can be easily separated by hand. Therefore, during the construction of the Magu sand subgrade, great attention must be paid to the compaction process, strictly control the compaction process, reasonably control the mechanical compaction power, press the large Magu sand mined into small granular shapes, fill the voids in the subgrade, reduce the void ratio, improve the overall strength and stability of the subgrade, and not break the Magu sand particles.

[0075] In addition, Magu sand is a coarse aggregate with good water stability. When filling the embankment, in order to prevent the impact on the underground soil and water, a subbase layer should be set under the subgrade to play an isolation role. The first layer of Magu sand subgrade filling material on the subbase layer is paved in full width to facilitate lateral drainage.

[0076] At the same time, the compaction power should be controlled within a reasonable range. It is necessary to ensure sufficient compaction and avoid excessive compaction energy, so that the particle size is rolled too small to achieve continuous grading, and at the same time avoid the phenomenon of particle size rebound and insufficient compaction of the filler.

[0077] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

[0078] The materials used in this construction method are Magu sand from the Funiu Mountain system in western Henan. The mechanical equipment and personnel configuration are as follows:

[0079] Serial number Equipment name Model specification Quantity 1 Excavator XE200GH 2 2 Bulldozer B160CL 2 3 Graders QSB6.7 1 4 Loader GD220 3 5 Dump truck HN3311B36C7BEV 10 6 Water truck ZBF5160GPSDFE6 2 7 Roller XS263J 2

[0080] Measured items and requirements:

[0081]

Claims

1. A method for roadbed construction using macadam sand filling materials, characterized in that: The steps include: S1 Foundation Treatment After removing the debris within the roadbed construction range by manual labor and bulldozers, the original ground is leveled with a grader, and the original ground is rolled before filling with a vibratory roller. The roadbed filling construction is carried out when the compaction degree reaches more than 90%; S2 lower sealing layer construction After the foundation treatment is completed, the roadbed lower sealing layer is set before the magu sand roadbed is filled. The material of the lower sealing layer is 50cm thick clay, cement soil and polypropylene filament needle-punched geotextile lower sealing layer. The first layer of magu sand material on the sealing layer is spread in full width; when grass planting protection or skeleton plant comprehensive protection is adopted, the slope surface is covered with 30cm thick planting soil; S3 Construction Stakeout Before the mahogany sand roadbed is filled on the lower sealing layer working surface that has been accepted, the layout structure (1) is used to measure and layout, the center pile and the left and right side piles of the road are laid out, the actual elevation is measured, and the design width of the roadbed is calculated. Then, the design width is widened by 0.5 meters on both sides, the filling construction side piles are marked, and then white lime is used to mark square grids along the longitudinal and transverse directions of the road surface. The specific width is determined according to the loading amount of each truck and the paving thickness, and one truck of mahogany sand is unloaded in each grid; S4 Layered filling S5 Paving and Leveling Bulldozers are used to spread the earthwork, and manual labor is used for construction. When spreading, the debris in the filler is cleaned up manually and piled in a designated place outside the roadbed to ensure that the maximum particle size of the filler is not greater than 10cm. First, the roadbed is leveled from both sides to the middle by manual labor and bulldozers along the direction of the roadbed, and then the bulldozer is used to stabilize the pressure 1 to 2 times. During mechanical leveling, the on-site inspection personnel use a ruler to measure the loose paving thickness at any time. If it does not meet the thickness requirements, it must be leveled again until the required loose paving thickness is reached, and the embankment construction surface is made into a 2% double-sided cross slope to facilitate roadbed drainage; S6 Drying S7 packing moisture content control After each paving of the magu sand, the on-site test personnel will test the moisture content of the paved magu sand filler. If the moisture content of the compacted magu sand is not within the range of ±2% of the optimum moisture content, water will be sprinkled; the watering is carried out twice, the first watering is 60% to 70% of the required water volume, and the roadbed surface is rolled 2 to 3 times when it is air-dried and does not stick to the wheels, and the second watering is 30% to 40% of the required water volume, and the roadbed surface is quickly rolled when it is air-dried and does not stick to the wheels. If the moisture content exceeds 2% of the optimum moisture content, it will be air-dried until it is within 2% of the optimum moisture content, and then quickly rolled; S8 roadbed rolling After the bulldozer is used to push the material for initial leveling, use the bulldozer to stabilize the pressure 1-2 times, use the grader to fine-level 1-2 times to ensure that the road arch cross slope is 2%, then use a 20T vibratory roller to vibrate lightly once and then vibrate heavily 3 times, and finally use the roller to statically compact 1-2 times. When vibrating and rolling, pay attention to the rolling speed from slow to fast, from weak vibration to strong vibration. The compaction routes are parallel to each other in the longitudinal direction. The straight section is rolled from both sides to the center of the roadbed, and the curved section is rolled from the inside of the curve to the outside. The transverse joints should overlap, and the front and rear adjacent sections should overlap in the longitudinal direction. The roller rolling speed is controlled at 30-70m / min, the frequency is 25-35Hz, the amplitude is not less than 2mm, and the rolling is carried out longitudinally from both sides to the middle, with the horizontal rolling wheels overlapping 30-50cm. During rolling, the roadbed should be compacted evenly without leakage, dead corners, softness, and peeling. The roadbed surface should be flat, the sideline should be straight, and the edge should be stable without slope loss. S9 compaction test Ensure that the compaction equipment and testing equipment are in good condition, ensure that the materials to be tested meet the design requirements, select representative test points according to the specifications, perform compaction operations according to the design requirements, record the number of compaction times and speed parameters, use a nuclear density meter or sand cone method to perform preliminary compaction tests, record the data, retrieve samples from the site, ensure that the samples are representative, use laboratory equipment to measure the maximum dry density and actual dry density of the samples, continue construction if qualified, and repeat mechanical rolling if unqualified; S10 Road Shaping Remove debris, loose materials and obstacles on the road surface, ensure that the base layer is flat and dense, and meets the design requirements, prepare shaping equipment and measuring tools, use a level or laser leveler to measure the road surface elevation, determine the shaping thickness, use a grader or scraper to perform preliminary shaping of the road surface, adjust the road surface elevation and slope, and make fine adjustments based on the measured data to ensure that the road surface flatness and slope meet the design requirements; S11 inspection.

2. A method for constructing a roadbed using macadam filling materials according to claim 1, characterized in that: Before construction, check the performance of the construction equipment and the supporting conditions and performance of the auxiliary construction vehicles to ensure that all equipment is working properly before construction.

3. The method for constructing a roadbed using macadam filling materials according to claim 1, characterized in that: Magu sand filling material meets the requirements of CBR and maximum particle size of stone-filled roadbed.

4. The method for constructing a roadbed using macadam filling materials according to claim 1, characterized in that: The settlement after rolling should tend to be stable, with the average settlement of the last two times not exceeding 3mm, or the average settlement being 5% to 10% of the total settlement.

5. The method for constructing a roadbed using macadam filling materials according to claim 1, characterized in that: The layout structure (1) comprises a base (11), a nut (13) is symmetrically fixedly connected to the surface of the base (11), the inner walls of the two nuts (13) are both screwed with a fixing screw (14), the lower end of the fixing screw (14) is arranged in a needle-like shape, the fixing screw passes through the base (11), a through-type through groove is provided in the middle of the surface of the base (11), two support plates (15) are symmetrically arranged on both sides of the surface of the base (11), the two support plates (15) are located on both sides of the through groove, a slide rail (16) is fixedly arranged between the two support plates (15), the outer wall of the slide rail (16) is slidably sleeved with two sliders (17), the side walls of the sliders (17) are both fixedly arranged with a cross plate (18), the inner walls of the two cross plates (18) are both fixedly arranged with a hydraulic cylinder (19), and the piston rod ends of the two hydraulic cylinders (19) are both fixedly arranged with a drill bit (12).

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