Inverted trapezoidal environmental protection cement stabilized road element in seasonal frozen region and preparation and construction method thereof

Abstract

The preparation and construction method of the inverted round trapezoidal environment-friendly cement stabilized road element in the seasonal frozen region belongs to the technical field of road traffic engineering, and the cement stabilized gravel mixture used includes rice straw fiber, ordinary Portland cement, aggregate and water, wherein the aggregate contains coarse aggregate and fine aggregate, and the rice straw fiber used has been pretreated. The road constructed by the cement stabilized road element is divided into three layers from bottom to top: a roadbed layer (1), a road element layer (2) and a road surface layer (3), wherein the road element layer (2) is composed of road elements (4) and fillers (5), and is characterized in that: the road elements (4) are multiple and are laid on the roadbed layer (1) at the same interval, each road element (4) is composed of a road element shell (6) and a road element core (11), the road element shell (6) is a prefabricated part; the road element shell (6) is in the shape of an inverted round trapezoid, and a road element shell cavity (8) is a cavity for containing the road element core (11). The present application is simple to make, has strong operability, low cost and obvious effect.

Description

Technical Field

[0001] The invention relates to an inverted truncated cone-shaped seasonally frozen zone environmentally friendly cement stabilized road component and a preparation and construction method thereof, belonging to the technical field of road traffic engineering. Background Art

[0002] Green, low-carbon, and circular development has become a global consensus. Heilongjiang Province, a major agricultural province in my country, is located in a seasonally frozen region. With a total permanent population of 37.719 million, 15.05 million of these people live in rural areas, accounting for 39.9%. This large rural population results in abundant crop resources, particularly straw, primarily composed of rice and corn straw. Straw contains nitrogen, phosphorus, potassium, carbon, hydrogen, and organic sulfur. Incomplete combustion of straw produces large amounts of sulfur dioxide, hydrocarbons, and soot. Under sunlight, it can also produce ozone, a secondary pollutant that harms the environment. The smoke produced by combustion is also harmful to health. Heilongjiang Province aims to achieve a straw resource utilization rate of over 92% by 2022. The province will continue to expand the breadth and depth of straw comprehensive utilization, creating more value from straw and promoting agricultural modernization and the achievement of the dual carbon goals. Therefore, recycling straw fiber not only saves money but also contributes to environmental sustainability, offering significant economic and social benefits. In recent years, crack control in cement-stabilized gravel bases has been extensively studied. Cement-stabilized crushed stone bases offer numerous advantages, such as good pressure bearing capacity and strong integrity. However, after forming, cement-stabilized crushed stone exhibits high stiffness and brittleness, making it susceptible to drying and thermal shrinkage cracking. Once cracks develop in the base layer, the coupled effects of humidity, temperature, and vehicle loads cause them to propagate, leading to stress concentrations at the bottom of the surface layer and the top of the base layer, resulting in cracking and damage in asphalt pavements. This is a major cause of early-stage pavement failure. Furthermore, Heilongjiang Province, a typical seasonally frozen region with long periods of low temperatures, large diurnal temperature swings, and difficult construction and curing, further contributes to widespread problems with cement-stabilized crushed stone bases, such as low strength and severe transverse cracking. Therefore, effectively controlling the shrinkage deformation of cement-stabilized crushed stone, improving its mechanical properties, and thereby suppressing shrinkage fracture, is a key issue in addressing pavement damage on semi-rigid bases. Current research focuses on improving the mechanical properties of the cement-stabilized crushed stone material itself, including optimizing aggregate grading, suppressing pre-cracking in the semi-rigid base layer, laying geotextiles, and adding various additives. Although these measures have a certain effect on preventing the cracking of cement-stabilized gravel bases, they cannot fundamentally solve the cracking problem of semi-rigid bases. Some researchers have tried to add admixtures such as basalt fiber, glass fiber, polypropylene fiber, and corn straw fiber to cement-stabilized gravel to improve its mechanical properties and crack resistance. Studies have shown that the addition of fibers has a great effect on enhancing the mechanical properties and crack resistance of pavement mixtures. However, there is currently little research on the influence and correlation of various factors after the addition of rice straw fiber to cement-stabilized gravel bases. These factors limit the application of rice straw fiber in actual engineering projects. The inverted truncated cone structure can gradually apply the gravity applied from above to the obliquely distributed side walls, greatly enhancing the supporting capacity of the component.The current road pavement is constructed by compacting the roadbed and directly pouring the sand stone cement concrete on the roadbed, and the cement is solidified to become an integral part. In the seasonal frozen region, the high temperature or severe cold winter is easy to appear the crack, and seriously affects the quality and cost of the constructed road. Therefore, how to construct the road in the seasonal frozen region, and how to use the straw and other agricultural waste to reduce the cost, and how to improve the mechanical properties and crack resistance of semi-rigid cement stabilized gravel, and how to improve the temperature control ability of the road itself become a difficult problem to be solved. Therefore, the inverted circular trapezoidal prefabricated road piece increases the overall support ability of the road piece layer, and the compressed straw filled in the road piece can use a large amount of straw, so as to achieve the purpose of constructing the road in the seasonal frozen region, using the straw and other agricultural waste to reduce the cost, improving the mechanical properties and crack resistance of semi-rigid cement stabilized gravel, and improving the road construction speed and the temperature control ability of the road itself, and it is necessary to invent an inverted circular trapezoidal environmental protection cement stabilized road piece in the seasonal frozen region and a preparation and construction method thereof. SUMMARY

[0003] In order to solve the problem of how to construct the road in the seasonal frozen region, and how to use the straw and other agricultural waste to reduce the cost, and how to improve the mechanical properties and crack resistance of semi-rigid cement stabilized gravel, and how to improve the temperature control ability of the road itself, the present application provides an inverted circular trapezoidal environmental protection cement stabilized road piece in the seasonal frozen region and a preparation and construction method thereof. The inverted circular trapezoidal environmental protection cement stabilized road piece in the seasonal frozen region and the preparation and construction method thereof use the inverted circular trapezoidal prefabricated road piece to increase the overall support ability of the road piece layer, and the compressed straw filled in the road piece can use a large amount of straw, so as to achieve the purpose of constructing the road in the seasonal frozen region, using the straw and other agricultural waste to reduce the cost, improving the mechanical properties and crack resistance of semi-rigid cement stabilized gravel, and improving the road construction speed and the temperature control ability of the road itself.

[0004] The technical scheme adopted by the present application to solve the technical problems is:

[0005] The cement-stabilized gravel mixture used in the inverted truncated cone-shaped environmentally friendly cement-stabilized road member for seasonally frozen areas of the present invention includes rice straw fiber, ordinary Portland cement, aggregate and water, wherein the aggregate includes coarse aggregate and fine aggregate, and the rice straw fiber used has been pre-treated. The specific weight composition ratio is as follows: 100 parts of aggregate; 4-5 parts of Portland cement; 5-6 parts of water; 0.6-1 part of rice straw fiber. The road constructed using the inverted truncated cone-shaped environmentally friendly cement-stabilized road member for seasonally frozen areas is divided into three layers from bottom to top: a road base layer 1, a road member layer 2, and a road surface layer 3, wherein the road member layer 2 is composed of road members 4 and fillers 5. There are multiple road members 4, which are laid on the road base layer 1 at equal intervals, and the distance between adjacent road members 4 is 5-10 cm; each road member 4 is composed of a road member shell 6 and a road member core 11. The road member shell 6 is the outer shell of the road member 4 and is made of a cement-stabilized gravel mixture. The cement-stabilized gravel mixture used is a kind of cement-stabilized gravel mixture. The aggregate used in the composite material has a particle size of no more than 0.5 cm. The road shell 6 is a prefabricated part. Each road shell 6 is composed of a road shell opening 7, a road shell cavity 8, a road shell bottom 9, and a road shell side wall 10. The road shell 6 is in the shape of an inverted truncated cone. The upper bottom diameter of the truncated cone road shell 6 is 20-30 cm, the lower bottom diameter is 10-20 cm, and the height is 10-30 cm. The road shell opening 7 is an opening formed by the lack of an upper bottom of the road shell 6. The diameter of the road shell opening 7 is 1 5-25 cm; the road piece shell cavity 8 is a cavity for holding the road piece core 11, the road piece shell cavity 8 is truncated cone-shaped, the diameter of the upper bottom circle of the truncated cone-shaped road piece shell cavity 8 is 15-25 cm, the diameter of the lower bottom circle is 5-15 cm, and the height is 8-20 cm. After the road piece core 11 is placed in the road piece shell cavity 8, the upper surface of the road piece core 11 is 71-2 cm from the road piece shell opening; the road piece shell bottom 9 is the bottom wall of the road piece shell 6, with a thickness of 1-5 cm; the road piece shell side wall 10 is the side of the road piece shell 6 around The wall has a thickness of 5 cm; the road member core 11 is a truncated cone, with a diameter of the upper bottom circle of 13-20 cm, a diameter of the lower bottom circle of 5-15 cm, and a height of 6-18 cm; the top surface 12 of the road member core is the upper bottom surface of the road member core 11; the bottom surface 13 of the road member core is the lower bottom surface of the road member core 11; the side wall 14 of the road member core is the side surface of the road member core 11; the filler 5 is made of a cement-stabilized gravel mixture, and the aggregate in the cement-stabilized gravel mixture used uses a gravel particle size of no more than 1 cm.

[0006] The cement-stabilized gravel mixture is prepared as follows: S1. First, coarse aggregates (2-2.5 cm, 1-2 cm, 0.5-1 cm) and fine aggregates (0-0.5 cm) of various grades are mixed in a weight ratio of 16:33:16:35, and stirred evenly to obtain first-grade gravel; S2. 0.6 parts of rice straw fiber, 5.9 parts of water, and 4.5 parts of Portland cement are added to the first-grade gravel and stirred evenly to obtain a cement-stabilized gravel mixture.

[0007] Preferably, the rice straw fiber used in this application needs to undergo the following pretreatment steps:

[0008] A1: Soak rice straw in 1.5 wt% H2O2 for 30 minutes, then wash the straw to neutrality and dry it for later use.

[0009] A2 Place the straw in a mixed solution of water and sodium hydroxide, turn on the magnetic stirrer, set the temperature to 70°C, stir for 60 minutes, and then wash to neutral.

[0010] By employing this technical solution, rice straw is first placed in H2O2 to remove polluting nitrogen and sulfur, allowing for clean straw utilization. The straw is then placed in a sodium hydroxide solution with a defined ratio and heated and stirred in a magnetic stirrer. This is done to increase the hydrolysis rate of hemicellulose, ensuring a more complete hydrolysis of small-molecule sugars, and to remove the non-polar structure formed by silicon and wax on the straw surface, thereby enhancing the interfacial adhesion between the rice fibers and the cement matrix.

[0011] The present invention also provides another method for preparing a cement-stabilized gravel mixture incorporating rice straw fiber, which adopts the following technical solution:

[0012] A method for preparing a cement-stabilized crushed stone mixture comprises the following steps:

[0013] S1 Determine the optimal moisture content and maximum dry density of the proposed mix ratio of rice straw fiber cement stabilized gravel mixture through compaction test;

[0014] S2: weighing each grade of aggregate according to a predetermined ratio and dry mixing them to obtain first-grade crushed stone;

[0015] S3: adding pretreated rice straw fibers to the first-level gravel and continuing dry mixing to obtain second-level gravel;

[0016] S4: adding some water to the secondary crushed stone and stirring the mixture, and then placing the mixture in a sealed bag and soaking it for 2 hours to obtain tertiary crushed stone;

[0017] S5: adding the remaining water and a predetermined amount of cement to the third-grade gravel and uniformly stirring the mixture to obtain a rice straw fiber cement-stabilized gravel mixture.

[0018] The beneficial effects of the present invention are that the inverted truncated cone-shaped environmentally friendly cement-stabilized road member in seasonally frozen areas and the preparation and construction method thereof utilize inverted truncated cone-shaped prefabricated road members, thereby increasing the overall supporting capacity of the road member layer, and the compressed straw filled in the middle of the road member can make large-scale use of straw, thereby achieving the purpose of using straw and other agricultural waste to reduce costs when building roads in seasonally frozen areas, and improving the mechanical properties and crack resistance of semi-rigid cement-stabilized gravel, and also improving the road construction speed and its own thermal insulation and temperature control capabilities.

[0019] The purpose of pretreatment of rice straw fiber is to increase the hydrolysis rate of hemicellulose and make the hydrolysis of small molecular sugars more complete. The second purpose is to remove the non-polar structure formed by silicon and wax on the straw surface and enhance the interfacial adhesion between rice fiber and cement matrix.

[0020] In addition, compared with the prior art, the present invention is also beneficial in that:

[0021] 1. Applying rice straw fiber to cement-stabilized gravel base effectively reduces the pollution caused by straw burning and improves the crack resistance of the base, which is a technology that is very consistent with my country's "dual carbon" goals.

[0022] 2. The present invention fully pre-treats rice straw fiber before incorporating it into the cement-stabilized gravel base, maximizing its performance improvement. Furthermore, the mixing process during the mixture preparation process is studied to ensure the uniform distribution of various raw materials in the cement-stabilized gravel.

[0023] 3. This application verifies the feasibility of using rice straw fiber cement stabilized gravel in seasonally frozen areas and derives relevant technical indicators.

[0024] 4. This application utilizes waste straw fibers to save natural resources and reduce project costs, and has great application prospects and social and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below with reference to the accompanying drawings.

[0026] Figure 1 This is a schematic diagram of the overall structure of the pavement after construction of inverted cone-shaped seasonally frozen zone environmentally friendly cement stabilized road components and their preparation and construction methods.

[0027] Figure 2 This is a schematic diagram of the overall structure of the road member shell of an inverted frustum-shaped seasonally frozen zone environmentally friendly cement-stabilized road member and its preparation and construction method.

[0028] Figure 3 The diagram shows the overall structure of the road member core of an inverted truncated cone-shaped seasonally frozen zone environmentally friendly cement stabilized road member and its preparation and construction method.

[0029] In the figure, 1. road base layer, 2. road component layer, 3. road surface layer, 4. road component, 5. filler, 6. road component shell, 7. road component shell opening, 8. road component shell cavity, 9. road component shell bottom, 10. road component shell side wall, 11. road component core, 12. road component core top surface, 13. road component core bottom surface, 14. road component core side wall. DETAILED DESCRIPTION

[0030] Example 1

[0031] The cement stabilized gravel mixture for the inverted trapezoidal environmental protection cement stabilized road element in the seasonal frozen region comprises rice straw fiber, ordinary Portland cement, aggregate and water, wherein the aggregate comprises coarse aggregate and fine aggregate, and the rice straw fiber used has been pretreated.

[0032] Aggregate 100 parts

[0033] Portland cement 4.5 parts

[0034] Rice straw fiber 0.6 parts

[0035] Water 5.9 parts

[0036] The preparation steps of the cement stabilized gravel mixture are as follows:

[0037] S1 first, mix the coarse aggregate (2-2.5 cm, 1-2 cm, 0.5-1 cm) and fine aggregate (0-0.5 cm) according to the weight ratio of 16:33:16:35, and then stir uniformly to obtain the first grade gravel.

[0038] S2 after the 0.6 parts of rice straw fiber, 5.9 parts of water and 4.5 parts of Portland cement are mixed into the above first grade gravel and stirred uniformly, the cement stabilized gravel mixture is prepared.

[0039] In this embodiment, the length of the rice straw fiber is 5 mm.

[0040] As preferred, the rice straw fiber used in the application needs to be pretreated by the following steps:

[0041] A1 the rice straw is soaked in 1.5wt% H2O2 for 30 min, and then the straw is washed to be neutral and dried for use.

[0042] A2 the straw is placed in a mixed solution of water and sodium hydroxide, a magnetic stirrer is started, the temperature is set to 70℃, and stirring is performed for 60 min, and then the straw is washed to be neutral.

[0043] By using the above technical scheme, the nitrogen and sulfur elements which will cause pollution are removed from the rice straw by placing the rice straw in H2O2, so that the rice straw can be used cleanly. Then the straw is placed in a sodium hydroxide solution with a certain proportion, and heated and stirred in a magnetic stirrer. This is done in order to increase the hydrolysis speed of hemicellulose, so that the hydrolysis of small molecule sugar substances is more sufficient, and to remove the non-polar structure formed by silicon and wax on the surface of the straw, and to enhance the interfacial adhesion between the rice fiber and the cement matrix.

[0044] The application also provides another preparation method of the cement stabilized gravel mixture incorporating rice straw fiber, which uses the following technical scheme:

[0045] A method for preparing a cement-stabilized crushed stone mixture comprises the following steps:

[0046] S1 Determine the optimal moisture content and maximum dry density of the proposed mix ratio of rice straw fiber cement stabilized gravel mixture through compaction test;

[0047] S2: weighing each grade of aggregate according to a predetermined ratio and dry mixing them to obtain first-grade crushed stone;

[0048] S3: adding pretreated rice straw fibers to the first-level gravel and continuing dry mixing to obtain second-level gravel;

[0049] S4: adding some water to the secondary crushed stone and stirring the mixture, and then placing the mixture in a sealed bag and soaking it for 2 hours to obtain tertiary crushed stone;

[0050] S5: adding the remaining water and a predetermined amount of cement to the third-grade gravel and uniformly stirring the mixture to obtain a rice straw fiber cement-stabilized gravel mixture.

[0051] Examples 2-9

[0052] Different from Example 1, the proportions of the cement-stabilized gravel mixtures in Examples 2-9 are different, as shown in Table 1 for details.

[0053] Table 1 Mixture ratios of Examples 1-9

[0054]

[0055] Control group:

[0056] Control group 1

[0057] The difference from Example 1 is that the control group 1 does not incorporate rice straw fiber.

[0058] Control group 2

[0059] The difference from Example 1 is that the rice straw fibers incorporated into the control group 2 were not subjected to a pretreatment process.

[0060] Test specimens were compacted and formed according to the mix ratios of the nine examples and two control groups at the optimal moisture content and maximum dry density. After curing for 28 days under standard conditions, specimens were subjected to the unconfined compressive strength test (T0805-1994), the splitting test (T0806-1994), the drying shrinkage coefficient test (T0854-2009), and the frost resistance test (T0858-2009) in accordance with the "Testing Procedures for Inorganic Binder Stabilized Materials for Highway Engineering" (JTGE51-2009). The test data are shown in Table 2.

[0061] Table 2 Test data

[0062]

[0063] The application can significantly improve the compressive strength, splitting tensile strength, freeze-thaw residual strength ratio and reduce the dry shrinkage coefficient of the cement stabilized macadam mixture by adding the rice straw fiber after the pretreatment process and selecting the content and length of the rice straw fiber. This makes it more suitable for the environment and temperature change in the seasonal freezing area during service, thereby achieving the purpose of improving the durability of the cement stabilized macadam base in the seasonal freezing area. In addition, the incorporation of the rice straw fiber into the cement stabilized macadam can not only improve the strength of the cement stabilized macadam, but also recycle the waste resources, reduce the production cost and reduce environmental pollution.

[0064] It is found from the test data in Table 2 that the performance of the cement stabilized macadam mixture prepared in Examples 1-9 is better than that of Comparative Example 1, which shows that the addition of the rice straw fiber is beneficial to the cement hydration in the cement stabilized macadam and enhances the combination of the aggregate and the fiber. As for the application of the rice straw fiber cement stabilized macadam in the seasonal freezing area, the improvement of the splitting tensile strength is more effective than the improvement of the compressive strength, because the rice straw fiber plays a role in strengthening and embedding stability, so that the axial tensile performance of the cement stabilized macadam is good; when the cement stabilized macadam is subjected to external force, the dispersed fiber tightly connects the mixture to resist the tensile force, thereby better improving the crack resistance of the cement stabilized macadam.

[0065] From the test data of Examples 1-9 and Comparative Example 2, it can be seen that the dry shrinkage coefficient of each group of test pieces after adding the rice straw fiber is significantly smaller than that of Comparative Example 1. This shows that the rice straw fiber can effectively inhibit the drying shrinkage of the cement stabilized macadam. The fiber has a reinforcing and anchoring effect, and when the internal tensile stress of the cement stabilized macadam is generated due to water loss, the anchoring effect of the fiber increases the tensile strength and offsets a part of the drying shrinkage stress, thereby improving the drying shrinkage.

[0066] Taking Examples 1, 4 and 7 as examples, it can be shown that compared with the fiber length, the fiber content has a more obvious effect on the freeze-thaw residual compressive strength ratio, and the freeze-thaw residual compressive strength ratio gradually increases with the increase of the fiber content. It can be seen that the incorporation of the rice straw fiber can obviously improve the frost resistance of the cement stabilized macadam, which is beneficial to its application in the seasonal freezing area.

[0067] It is found from the comparison of the test data of Example 1 and Comparative Example 2 that the pretreatment process of the rice straw fiber before being incorporated into the cement stabilized macadam mixture can effectively enhance the combination of the rice straw and the cement-based material, thereby better improving the overall performance.

[0068] In the three groups of Examples 1-3, 4-6, and 7-9, different fiber lengths were optimized at the same fiber dosage. The results showed that with the increase of fiber length, the compressive strength and splitting strength of cement-stabilized gravel both showed a trend of first increasing and then decreasing. The increase in fiber length made it easier for the fibers to form a network structure in the mixture. In addition, as shown in Examples 3, 6, and 9, with the increase of fiber length, the shrinkage coefficient of cement-stabilized gravel gradually decreased. The shrinkage coefficient was the smallest when the fiber length was 15 mm in each group of Examples. However, when the fiber length was too long, it was difficult for the fibers to be evenly dispersed in the mixture, resulting in the fibers agglomerating into clumps. This aggregation led to a decrease in the overall mechanical strength of cement-stabilized gravel. Taking all the above factors into consideration, at the same dosage, when the fiber length was 10 mm, the performance improvement of cement-stabilized gravel was better.

[0069] Comparing Examples 2, 5, and 8, all with a fiber length of 10 mm, reveals that the various properties of cement-stabilized macadam gradually decline with increasing fiber content, while the fiber content in Example 5 achieves superior results in terms of unconfined compressive strength, splitting tensile strength, freeze-thaw strength residual ratio, and shrinkage coefficient. This is because excessive fiber content weakens the bond between the fiber and the cement-based mixture, thereby reducing the close connection between the fiber and the cement-based mixture. This shows that the fiber content and length have a significant impact on the performance of cement-stabilized macadam, and selecting a reasonable fiber content and length can significantly improve the performance of the cement-stabilized macadam base.

[0070] Example 10

[0071] The application discloses a rounded-trapezoidal environment-friendly cement stabilized road element in a seasonal frozen region and a preparation and construction method thereof. The rounded-trapezoidal environment-friendly cement stabilized road element in a seasonal frozen region is composed of a roadbed layer 1, a road element layer 2, a road surface layer 3, a road element 4, a filler 5, a road element shell 6, a road element shell opening 7, a road element shell cavity 8, a road element shell bottom 9, a road element shell side wall 10, a road element core 11, a road element core top surface 12, a road element core bottom surface 13 and a road element core side wall 14. The roadbed layer 1 is the lowermost layer structure of a roadbed of a road to be built, is formed by leveling the ground at the original position by a machine, laying slag or gravel, compacting by a road roller or gravity, laying 10-30 cm thick gravel mixture on the surface of the leveled slag or gravel, leveling the upper surface of the roadbed layer 1 by a machine before the gravel mixture solidifies, and is used for supporting the road element layer 2 and the road surface layer 3. The road element layer 2 is the middle layer of the road to be built, is composed of the road element 4 and the filler 5, a plurality of the road element 4 is laid on the roadbed layer 1 at the same interval, the road element shell bottom 9 under the road element 4 is located on the upper surface of the roadbed layer 1, and the road element shell bottom 9 is smeared with cement slurry when being laid, so that the road element shell bottom 9 and the upper surface of the roadbed layer 1 are in close contact. The distance between two adjacent road elements 4 is 5-10 cm, so that a gap with a width of at least 5 cm is formed between the two adjacent road elements 4, and the filler 5 is filled between the two adjacent road elements 4. Each road element 4 is composed of the road element shell 6 and the road element core 11. The road element shell 6 is the outer shell of the road element 4, is made of cement stabilized gravel mixture, the aggregate in the cement stabilized gravel mixture has a particle size of not more than 0.5 centimeters, therefore, the road element shell 6 is a prefabricated element for containing the road element core 11, which can greatly increase the speed of road construction; each road element shell 6 is composed of a road element shell opening 7, a road element shell cavity 8, a road element shell bottom 9, and a road element shell side wall 10, and is in the shape of an inverted circular truncated cone, the upper base diameter of the circular truncated cone-shaped road element shell 6 is 20-30 centimeters, the lower base diameter is 10-20 centimeters, and the height is 10-30 centimeters, the road element shell opening 7 is an opening formed by the lack of the upper base of the road element shell 6, and the road element core 11 is inserted into the road element shell cavity 8 from the road element shell opening 7, and the diameter of the road element shell opening 7 is 15-25 centimeters; the road element shell cavity 8 is a cavity for containing the road element core 11, and the road element shell cavity 8 is in the shape of a circular truncated cone, the diameter of the upper base circle of the circular truncated cone-shaped road element shell cavity 8 is 15-25 centimeters, the diameter of the lower base circle is 5-15 centimeters, and the height is 8-20 centimeters, after the road element core 11 is placed in the road element shell cavity 8, the upper surface of the road element core 11 is 1-2 centimeters away from the road element shell opening 7, so that when the road is being repaired, the cement stabilized macadam mixture of the road surface layer 3 is filled into the upper part of the road element shell cavity 8, and downwardly forms a protrusion that is engaged with the road element shell 6, at the same time, with the aid of the filler 5, the road surface layer 3 and the road element layer 2 are more firmly connected together to form a whole, and the road element shell opening 7 is sealed to prevent moisture from penetrating into the road element shell cavity 8 and causing the road element core 11 containing fibers to expand and damage the road; the road element shell bottom 9 is the bottom wall of the road element shell 6, and the thickness is 1-5 centimeters; the road element shell side wall 10 is the side wall around the road element shell 6, and the thickness is 5 centimeters, since the road element shell 6 lacks an upper base, the cavity surrounded by the road element shell side wall 10 and the road element shell bottom 9 is the road element shell cavity 8; the road element core 11 is obtained by uniformly mixing straw powder, water, and cement in a ratio of 2:0.3:1, and then pressing in a circular truncated cone-shaped mold under high pressure, after the cement solidifies, the road element core 11 forms a circular truncated cone-shaped prefabricated element, the diameter of the upper base circle of the circular truncated cone-shaped road element core 11 is 13-20 centimeters, the diameter of the lower base circle is 5-15 centimeters, and the height is 6-18 centimeters; the road element core top surface 12 is the upper surface of the road element core 11, and after the road element core 11 is placed in the road element shell cavity 8, there is still a part of the road element shell cavity 8 above the road element core top surface 12; the road element core bottom surface 13 is the lower surface of the road element core 11, and when it is set, a layer of cement slurry prepared by water and cement in a ratio of 0.5:1 is brushed on the road element core bottom surface 13 in advance, so that the road element core bottom surface 13 and the upper surface of the road element shell bottom 9 are tightly connected together to form a whole; the road element core side wall 14 is the side surface of the road element core 11, and when it is set, a layer of cement slurry prepared by water and cement in a ratio of 0.5:1 ratio of cement slurry, so that the core side wall 14 and the shell side wall 10 are tightly connected together to form a whole; the filler 5 is made of cement stabilized gravel mixture, the aggregate of which uses gravel with a particle size of not more than 1 cm, after the mixing of the filler 5, it is poured into the gap between the adjacent road blocks 4, and is vibrated by a vibrating rod to make the cement stabilized gravel mixture fill completely to prevent the formation of air bubbles and ensure the quality of the constructed road; the road surface layer 3 is the uppermost layer of the road, which is above the road block layer 2 and is poured by cement stabilized gravel mixture, the aggregate of which uses gravel with a particle size of not more than 2.65 cm.

[0072] The above shows and describes the basic features and main characteristics of the present application and the advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for preparing and constructing an inverted truncated cone-shaped environmentally friendly cement-stabilized road member for seasonally frozen areas, wherein the cement-stabilized crushed stone mixture used comprises rice straw fiber, ordinary Portland cement, aggregate, and water, wherein the aggregate comprises coarse aggregate and fine aggregate, wherein the rice straw fiber used has been pretreated; the weight composition ratio thereof is: 100 parts of aggregate; 4-5 parts of Portland cement; 5-6 parts of water; and 0.6-1 part of rice straw fiber; a road constructed using the inverted truncated cone-shaped environmentally friendly cement-stabilized road member for seasonally frozen areas is divided into three layers from bottom to top: a road base layer (1), a road member layer (2), and a road surface layer (3), wherein the road member layer (2) is composed of road members (4) and fillers (5), and the method is characterized in that: The road piece (4) is a plurality of road pieces, which are laid on the road base (1) at the same interval, and the distance between two adjacent road pieces (4) is 5-10 cm; each road piece (4) is composed of a road piece shell (6) and a road piece core (11), the road piece shell (6) is the outer shell of the road piece (4), and is made of a cement-stabilized crushed stone mixture. The aggregate in the cement-stabilized crushed stone mixture has a crushed stone particle size of no more than 0.5 cm. The road piece shell (6) is a prefabricated part; each road piece shell (6) is composed of a road piece shell mouth (7), The road piece shell cavity (8), the road piece shell bottom (9), the road piece shell side wall (10) is composed, the road piece shell (6) is inverted truncated cone shape, the upper bottom diameter of the truncated cone shaped road piece shell (6) is 20-30 cm, the lower bottom diameter is 10-20 cm, and the height is 10-30 cm. The road piece shell mouth (7) is an opening formed by the lack of the upper bottom of the road piece shell (6). The diameter of the road piece shell mouth (7) is 15-25 cm; the road piece shell cavity (8) is a cavity for holding the road piece core (11). The road piece shell cavity (8) is round The upper bottom circle diameter of the truncated cone-shaped road piece shell cavity (8) is 15-25 cm, the lower bottom circle diameter is 5-15 cm, and the height is 8-20 cm. After the road piece core (11) is placed in the road piece shell cavity (8), the upper surface of the road piece core (11) is 1-2 cm away from the road piece shell opening (7); the road piece shell bottom (9) is the bottom wall of the road piece shell (6), with a thickness of 1-5 cm; the road piece shell side wall (10) is the side wall around the road piece shell (6), with a thickness of 5 cm; the road piece core (11) is truncated cone-shaped, The diameter of the upper bottom circle is 13-20 cm, the diameter of the lower bottom circle is 5-15 cm, and the height is 6-18 cm. The road member core (11) is a prefabricated member. The top surface (12) of the road member core is the upper bottom surface of the road member core (11). The bottom surface (13) of the road member core is the lower bottom surface of the road member core (11). The side wall (14) of the road member core is the side surface of the road member core (11). The filler (5) is made of a cement-stabilized crushed stone mixture. The aggregate in the cement-stabilized crushed stone mixture has a crushed stone particle size of no more than 1 cm. The rice straw fiber used needs to go through the following pretreatment steps: A1: Soak rice straw in 1.5 wt% H2O2 for 30 min, then wash the straw to neutrality and dry it for later use; A2: Place the straw in a mixture of water and sodium hydroxide, turn on a magnetic stirrer, set the temperature to 70°C, stir for 60 minutes, and then wash to neutrality; By adopting the above-mentioned pretreatment steps, the rice straw is first placed in H2O2 to remove nitrogen and sulfur elements that may cause pollution, so that the straw can be used cleanly; then the straw is placed in a sodium hydroxide solution and heated and stirred in a magnetic stirrer. This is done to increase the hydrolysis rate of hemicellulose and make the hydrolysis of small molecular sugar substances more complete, and secondly, to remove the non-polar structure formed by silicon and wax on the surface of the straw, thereby strengthening the interfacial bonding between the rice fiber and the cement matrix.

2. The method for preparing and constructing the inverted truncated cone-shaped environmentally friendly cement stabilized road member for seasonally frozen areas according to claim 1, characterized in that: The cement-stabilized gravel mixture used was prepared as follows: S1. First, coarse aggregates (2-2.5 cm, 1-2 cm, 0.5-1 cm) and fine aggregates (0-0.5 cm) of various grades were mixed in a weight ratio of 16:33:16:35, and stirred evenly to obtain first-grade gravel; S2. 0.6 parts of rice straw fiber, 5.9 parts of water, and 4.5 parts of Portland cement were added to the first-grade gravel and stirred evenly to obtain a cement-stabilized gravel mixture.

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