Road water-stabilizing layer mixing material and mixing method thereof

Abstract

The present invention discloses a road water-stabilizing layer mixture and a mixing method thereof. The road water-stabilizing layer mixture comprises the following materials in parts by weight: 3 to 11 parts of a binder, 81 to 96 parts of a stabilized material, and 1 to 8 parts of water. The binder is ordinary Portland cement and an alkali-activated cementitious material, and the stabilized material is clay-based recycled aggregate and washed sand. Since the stabilized materials in the present invention are clay-based recycled aggregate and washed sand, the large amount of engineering slag and silt generated during the construction and maintenance of water conservancy projects in plain rural areas can be fully utilized as raw materials for efficient and high-value-added resource utilization, making it convenient to obtain materials locally, effectively reducing the raw material cost and transportation cost of the road water-stabilizing layer mixture, and being beneficial to the sustainable development of new rural road construction and renovation. In addition, since clay-based recycled aggregate can effectively replace natural stone, the demand for natural stone in rural road construction is greatly reduced, protecting the natural ecological environment.

Description

Technical Field

[0001] The invention belongs to the field of highway pavement base construction, and in particular relates to a road water-stabilizing layer mixing material and a mixing method thereof. Background Art

[0002] By the end of 2022, China's highway mileage reached 5.3548 million kilometers, while rural roads totaled 4.5314 million kilometers, including 699,600 kilometers of county roads, 1.2432 million kilometers of township roads, and 2.5886 million kilometers of village roads. Rural roads account for 85% of the country's total highway mileage. Highway construction requires a large amount of gravel, but nearly one-third of my country's plains make it difficult to obtain the gravel needed for highway construction. Furthermore, the large-scale construction projects of recent decades have led to a shortage of high-quality stone in many areas. Furthermore, excessive stone mining can lead to vegetation destruction, soil erosion, mountain instability, and damage to the ecological environment critical to plant and animal life.

[0003] With the continuous advancement of new rural construction, the cost and quality of rural road construction are related to the sustainable development of new rural construction. Since sand and gravel aggregates often account for more than two-thirds of the road construction process, especially the amount of gravel in the road water-stabilizing layer can reach more than 80%, for rural areas in plain areas, there is a lack of local stone materials. Transporting gravel over long distances for road construction will undoubtedly greatly increase the cost of the project. The recycled aggregates mentioned in the prior art are used for municipal road construction, mostly for municipal roads not far from the demolition of buildings. For rural areas far away from cities, it is not economical to transport recycled aggregates over long distances for road construction. For the vast plains, there is still a lack of effective solutions for the high-value-added resource utilization of the large amount of engineering debris and silt generated during the construction and maintenance of water conservancy projects. Summary of the Invention

[0004] Aiming at the current problems of shortage of gravel required for rural road construction in plain areas of my country, large amount of engineering debris and silt generated during the construction and maintenance of water conservancy projects, and lack of high value-added resource utilization technology solutions, the present invention proposes a road water-stabilizing layer mixture and a mixing method thereof.

[0005] The present invention provides a road water-stabilizing layer mixture, which comprises the following materials in parts by weight: 3 to 11 parts of a binder, 81 to 96 parts of a stabilized material, and 1 to 8 parts of water. The binder is ordinary Portland cement and an alkali-activated cementitious material, and the stabilized material is clay-based recycled aggregate and washed sand.

[0006] Furthermore, the activator used in the alkali-activated gelling material is one or more of water glass and sulfate activator;

[0007] The sulfate activator comprises the following raw materials in parts by weight: 27 to 80 parts of quicklime powder, 0 to 67 parts of dihydrate gypsum, and 6 to 20 parts of sodium sulfate.

[0008] Furthermore, the washed sand is sand that is washed with water after separation of engineering debris mud and sand, has a fineness modulus of 2.0 to 2.5, and a mud content of less than 3%.

[0009] Furthermore, the stabilized material includes the following materials in parts by weight: 75-95 parts of clay-based recycled aggregate and 5-25 parts of washed sand;

[0010] The particle gradation of the clay-based recycled aggregate is: 0 to 100 parts of 10 mm particle size, 0 to 100 parts of 20 mm particle size, and 0 to 100 parts of 30 mm particle size.

[0011] Furthermore, the clay-based recycled aggregate comprises the following raw materials in parts by weight: 50 to 96 parts of clay base material, 4 to 56 parts of cementitious material, 0 to 28 parts of mineral admixture, and 0 to 50 parts of water;

[0012] The clay-based material includes: one or more of river, lake and sea sedimentary soil, engineering mud, engineering spoil, tailings with a particle size of less than 2.36 mm, sandy loam, loam, clay and silt; the cementitious material is ordinary Portland cement; the mineral admixture includes: one or more of waste slag and stone powder in the ceramic firing process; and the water is fresh water.

[0013] Furthermore, the method for producing the clay-based recycled aggregate comprises the following steps:

[0014] S1. Weigh the raw materials according to the designed ratio. The clay base material is weighed in two parts, with the mass percentages of the first and second parts being 70% and 30% respectively. Add the cementitious material to the first part of the clay material and stir. Then add the second part of the clay base material, mineral admixtures and water and stir;

[0015] S2, adding the stirred mixture to a clay-based recycled aggregate extrusion molding device to extrude the clay-based recycled aggregate;

[0016] S3. Carry out indoor curing, water immersion curing or carbonization curing on clay-based recycled aggregate.

[0017] Furthermore, the carbonization curing conditions of the clay-based recycled aggregate are: temperature 3-48° C., relative humidity 36-62%, and pressure 0-2.8 MPa.

[0018] Furthermore, the clay-based recycled aggregate has a 28d cylinder compressive strength greater than 2MPa, a crushing index less than 30%, and a 1h water absorption rate less than 20%.

[0019] The present invention provides a mixing method for a road water-stabilizing layer mixture, the mixing method comprising the following steps:

[0020] P1. Evenly mix the weighed binder and water into a slurry;

[0021] P2. Mix the weighed stabilized materials evenly;

[0022] P3, add the slurry in P1 to the stabilized material in P2 and stir evenly to form a mixture;

[0023] P4. Transport the mixture in P3 to the road construction site for water-stabilizing layer construction.

[0024] Furthermore, the initial setting time of the binder is greater than 3 hours, the final setting time is 6 to 10 hours, and the unconfined compressive strength of the water-stable layer 7d is 2 to 4.5 MPa.

[0025] The stabilized materials in this invention utilize clay-based recycled aggregate and washed sand, and the raw materials are the large quantities of construction debris and silt generated during the construction and maintenance of water conservancy projects in plain rural areas. This allows for efficient and high-value resource utilization, making it convenient to source local materials. This material can be used in highway construction in plain rural areas, effectively reducing the raw material and transportation costs of the road water-stabilizing layer mix, thus facilitating the sustainable development of new rural highway construction and renovation. Furthermore, because clay-based recycled aggregate can effectively replace natural stone, it significantly reduces the demand for natural stone in rural road construction, avoids the damage to natural mountains and surface vegetation caused by stone mining, and protects the natural ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of an ellipsoidal clay-based recycled aggregate.

[0027] Figure 2 This is a schematic diagram of a mixing method for road water-stabilizing layer mixing material.

[0028] Figure 3 This is a schematic diagram of an extrusion molding device for producing clay-based recycled aggregate.

[0029] Figure 4 Schematic diagram of an aggregate vibrating screen for clay-based recycled aggregate production equipment.

[0030] In the figure: 7, extrusion molding equipment; 22, feed port; 23, double-roller extrusion device; 24, aggregate vibrating screen; 25, residual material conveyor belt; 26, extrusion controller; 27, double-roller wheels; 28, extrusion motor; 29, roller cleaning machine; 30, hemispherical groove; 31, screen bracket; 32, aggregate screen; 33, vibration motor; 34, flexible bracket; 35, flexible cover. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0032] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0033] The road water-stabilizing layer mixture of the present invention comprises the following materials in parts by weight: 3 to 11 parts of a binder, 81 to 96 parts of a stabilized material, and 1 to 8 parts of water, wherein the binder is ordinary Portland cement and an alkali-activated cementitious material, and the stabilized material is clay-based recycled aggregate and washed sand.

[0034] Specifically, the washed sand in the stabilized material is the washed sand after the construction waste is separated from the mud and sand; the clay-based recycled aggregate in the stabilized material is the mud cake after the separation of the mud and sand of the construction waste and the coarse aggregate made by solidifying the silt generated during the maintenance of the water conservancy project.

[0035] The stabilized materials used in the road water-stabilizing layer mixtures in the embodiments of the present invention are all engineering debris and silt generated during the construction and maintenance of water conservancy projects in plain rural areas, representing high-value-added resource products. Because the stabilized materials are all locally sourced, transportation and material costs are significantly reduced, while also conserving significant amounts of natural sand and gravel and mineral resources, protecting the natural ecological environment.

[0036] Optionally, the activator used for the alkali-activated cementitious material is one or more of water glass and sulfate activator; the sulfate activator includes the following raw materials in parts by weight: 27 to 80 parts of quicklime powder, 0 to 67 parts of dihydrate gypsum, and 6 to 20 parts of sodium sulfate.

[0037] Specifically, the alkali-activated cementitious material used is solid waste mineral powder from steelmaking in steel mills, which facilitates the use of local materials for road construction in rural areas near steel mills, thereby saving rural road construction costs.

[0038] Optionally, the washed sand has a fineness modulus of 2.0 to 2.5 and a mud content of less than 3%. The washed sand used is a resource product of engineering slag, which is convenient for local material and reduces transportation costs, thereby saving rural road construction costs.

[0039] Optionally, the stabilized material includes the following materials in parts by weight: 75-95 parts of clay-based recycled aggregate and 5-25 parts of washed sand; the particle grading of the clay-based recycled aggregate is: 0-100 parts of 10mm particle size, 0-100 parts of 20mm particle size, and 0-100 parts of 30mm particle size.

[0040] Optionally, the clay-based recycled aggregate comprises the following raw materials in parts by weight: 50-96 parts of clay base material, 4-56 parts of cementitious material, 0-28 parts of mineral admixture, and 0-50 parts of water;

[0041] Specifically, the clay-based material includes: one or more of river, lake and sea sedimentary soil, engineering mud, engineering waste soil, tailings with a particle size of less than 2.36 mm, sandy loam, loam, clay and silt; the cementitious material is ordinary Portland cement; the mineral admixture includes: one or more of waste slag and stone powder in the ceramic firing process; and the water is fresh water.

[0042] The embodiments of the present invention make full use of solid waste from the raw materials of clay-based recycled aggregates, which is not only beneficial to the resource treatment of solid waste and reduces the adverse effects of solid waste on the natural environment and production and life, but also significantly improves the technical level of resource utilization of solid waste, which is beneficial to the high-quality development of the solid waste resource treatment industry.

[0043] Optionally, the method for producing clay-based recycled aggregate comprises the following steps:

[0044] S1. Weigh the clay-based recycled aggregate raw materials according to the designed ratio. The clay-based material is weighed in two parts, with the mass percentages of the first and second parts being 70% and 30% respectively. The weighed cementitious material is added to the first part of the clay material and stirred. Then, the second part of the clay-based material is added, and the weighed mineral admixture and water are added and stirred.

[0045] S2, adding the stirred mixture to the clay-based recycled aggregate extrusion molding device 7 to extrude the clay-based recycled aggregate;

[0046] S3. Carry out indoor curing, water immersion curing or carbonization curing on clay-based recycled aggregate.

[0047] Specifically, the extrusion molding device 7 includes: a feed port 22, a double-roller extrusion device 23, an aggregate vibrating screen 24, a residual material conveyor belt 25, and an extrusion controller 26. The feed port 22 is located above the double-roller extrusion device 23, and the feed port 22 is connected to the mixing device via a mixing material conveyor belt. The double-roller extrusion device 23 is located above the aggregate vibrating screen 24, and the aggregate vibrating screen 24 is located above the residual material conveyor belt 25. The extrusion controller 26 is connected to the extrusion molding device 7. The extrusion molding device 7 extrudes the mixed material into clay-based recycled aggregate, achieving large-scale production of colloidal waste with a high moisture content without drying, providing production equipment support for sustainable development and waste-free city construction.

[0048] Optionally, the roller extrusion device 23 includes: a roller wheel 27, an extrusion motor 28 and a roller cleaning machine 29. The surface of the roller wheel 27 is provided with a plurality of hemispherical grooves 30. The roller wheel 27 is connected to the extrusion motor 28. The roller cleaning machine 29 is connected to the extrusion controller 26. The roller cleaning machine 29 is located above the roller wheel 27. By providing the hemispherical grooves 30 on the surface of the roller wheel 27, the mixture of the colloidal waste with a high water content is squeezed into Figure 1 The ellipsoidal clay-based recycled aggregate shown in the figure enables the clay-based recycled aggregate to be tightly combined together through physical action before molding, thereby reducing the porosity of the clay-based recycled aggregate, ensuring the uniformity and integrity of the particle shape of the clay-based recycled aggregate, and effectively promoting the strength growth of the clay-based recycled aggregate.

[0049] Optionally, five extrusion molding devices 7 are provided, including two with roller grooves having a diameter of 10 mm, two with roller grooves having a diameter of 20 mm, and one with a diameter of 30 mm. Extrusion molding devices 7 with roller grooves having diameters of 30 mm, 20 mm, and 10 mm are provided in order from near to far from the mixing device. By providing extrusion molding devices 7 with different particle sizes, the particle size requirements of clay-based recycled aggregate for different applications can be met. Simultaneously, the extrusion molding device 7 with a larger particle size is provided closest to the mixing device, which facilitates the extrusion of the residual material conveyed by the residual material conveyor belt 25 into clay-based recycled aggregate with a larger particle size first, and then into clay-based recycled aggregate with a smaller particle size.

[0050] Optionally, the carbonization curing conditions for the clay-based recycled aggregate are: temperature of 3-48°C, relative humidity of 36-62%, and pressure of 0-2.8 MPa. The clay-based recycled aggregate used in the road water-stabilizing layer mixture is simple to manufacture and is easy to manufacture on a large scale. It can effectively meet the natural stone substitute aggregate requirements for rural road construction. Furthermore, the produced clay-based recycled aggregate can also be used in other projects related to new rural construction, significantly reducing the dependence of vast plain rural areas on natural stone resources. This contributes to the high-quality development of new rural construction projects in plain rural areas and improves the new quality productivity of new rural areas.

[0051] Optionally, the clay-based recycled aggregate has a 28d cylinder compressive strength greater than 2 MPa, a crushing index less than 30%, and a 1h water absorption rate less than 20%.

[0052] like Figure 2 As shown, a method for mixing a road water-stabilizing layer mixture comprises the following steps:

[0053] P1. Evenly mix the weighed binder and water into a slurry;

[0054] P2. Mix the weighed stabilized materials evenly;

[0055] P3, add the slurry in P1 to the stabilized material in P2 and stir evenly to form a mixture;

[0056] P4. Transport the mixture in P3 to the road construction site for water-stabilizing layer construction.

[0057] Optionally, the initial setting time of the binder is greater than 3 hours, the final setting time is 6 to 10 hours, and the unconfined compressive strength of the water-stable layer 7d is 2 to 4.5 MPa.

[0058] The mixing method of the road water-stabilizing layer mixture described in the present invention has smaller resistance between coarse aggregates during the mixing process due to the clay-based recycled aggregate used, which is different from traditional natural stone. The mixing method of adding slurry to sand and gravel aggregate is more conducive to the full mixing of different components of the mixture, effectively avoiding problems such as insufficient and unbalanced bonding between the binder and the stabilized material, and can effectively improve the mixing quality of the mixture, thereby improving the construction quality of the water-stabilizing layer.

[0059] Example 1

[0060] In this embodiment, the road water-stabilizing layer mixture includes the following materials in parts by weight: 11 parts of 32.5 grade ordinary Portland cement, 81 parts of stabilized materials and 8 parts of water. The stabilized materials include the following materials in parts by weight: 75 parts of clay-based recycled aggregate and 25 parts of washed sand. The particle grading of the clay-based recycled aggregate is: 100 parts of 10 mm particle size, 0 parts of 20 mm particle size, and 0 parts of 30 mm particle size. The fineness modulus of the washed sand is 2.0, and the mud content is 1.6%.

[0061] The clay-based recycled aggregate includes the following raw materials in parts by weight: 60 parts of engineering waste with a moisture content of 7%, 20 parts of 42.5-grade ordinary Portland cement, and 20 parts of tap water. The engineering waste is the mud cake obtained by separating the mud and sand from the engineering debris and then naturally drying and crushing it into powder. The raw materials of the clay-based recycled aggregate are weighed according to the designed ratio. The clay base material is weighed in two parts, and the mass percentages of the first and second parts are 70% and 30% respectively. The weighed cementitious material is added to the first part of the clay material and stirred. Then, the second part of the clay base material is added and the weighed external admixtures and water are added and stirred. The stirred mixture is added to the clay-based recycled aggregate extrusion molding equipment to extrude the clay-based recycled aggregate. The clay-based recycled aggregate is cured indoors. The aggregate produced by the extrusion molding equipment is as follows: Figure 1 As shown, both sides of the relative structure are arched structures, similar to a spindle. After 28 days of indoor curing, the cylinder compressive strength of the clay-based recycled aggregate is 2.9 MPa, the crushing index is 16.5%, and the water absorption rate is 11% in 1 hour. After 28 days of water-immersion curing, the cylinder compressive strength of the clay-based recycled aggregate is 4.1 MPa, the crushing index is 14.3%, and the water absorption rate is 9% in 1 hour.

[0062] When used in a road cement stabilization layer, the mixing method is as follows: First, mix 11 parts of 32.5-grade ordinary Portland cement with 8 parts of water to form a slurry. Then, mix 81 parts of the stabilizing material (75 parts of clay-based recycled aggregate and 25 parts of washed sand) evenly. The slurry is then added to the stabilizing material and mixed evenly to form a mixture. The mixture is then transported to the road construction site for cement stabilization layer construction. The 32.5-grade ordinary Portland cement used has an initial setting time of 4.6 hours and a final setting time of 6.4 hours. The cement stabilization layer has an unconfined compressive strength of 2 MPa at 7 days.

[0063] Example 2

[0064] In this embodiment, the road water-stabilizing layer mixture includes the following materials in parts by weight: 3 parts of 32.5 grade ordinary Portland cement, 96 parts of stabilized materials and 1 part of water. The stabilized materials include the following materials in parts by weight: 95 parts of clay-based recycled aggregate and 5 parts of washed sand. The particle grading of the clay-based recycled aggregate is: 0 parts of 10 mm particle size, 100 parts of 20 mm particle size, and 0 parts of 30 mm particle size. The fineness modulus of the washed sand is 2.5, and the mud content is 2.1%.

[0065] Among them, the clay-based recycled aggregate includes the following raw materials in parts by weight: 60 parts of river, lake and sea sedimentary soil with a moisture content of 7%, 13.3 parts of 42.5-grade ordinary Portland cement, 6.7 parts of waste residue from the ceramic firing process, and 20 parts of tap water. The mud cake after separation of mud and sand from the river, lake and sea sedimentary soil is naturally dried and crushed to obtain powder. The particle size of the waste residue from the ceramic firing process is 1.18 mm. The raw materials of the clay-based recycled aggregate are weighed according to the designed ratio. The clay base material is weighed in two parts, and the mass percentages of the first and second parts are 70% and 30% respectively. The weighed cementitious material is added to the first part of the clay material and stirred. Then, the second part of the clay base material is added and the weighed external admixtures and water are added and stirred. The stirred mixture is added to the clay-based recycled aggregate extrusion molding equipment to extrude the clay-based recycled aggregate. The clay-based recycled aggregate is cured indoors. The aggregate produced by the extrusion molding equipment is as follows: Figure 1 As shown in the figure, the cylinder compressive strength of the clay-based recycled aggregate after 28 days of indoor curing is 2.4 MPa, the crushing index is 17.6%, and the water absorption rate is 10% in 1 hour; the cylinder compressive strength of the clay-based recycled aggregate after 28 days of water-immersion curing is 3.9 MPa, the crushing index is 14.8%, and the water absorption rate is 9% in 1 hour.

[0066] When used in road cement stabilization layers, the mixing method is as follows: First, mix 3 parts 32.5-grade ordinary Portland cement with 1 part water to form a slurry. Then, evenly mix 96 parts of the stabilizing material (95 parts clay-based recycled aggregate and 5 parts washed sand). The slurry is then added to the stabilizing material and mixed thoroughly to form a mixture. The mixture is then transported to the road construction site for cement stabilization layer construction. The 32.5-grade ordinary Portland cement used has an initial setting time of 4.1 hours and a final setting time of 6.0 hours. The cement stabilization layer has an unconfined compressive strength of 2.5 MPa at 7 days.

[0067] Example 3

[0068] In this embodiment, the road water-stabilizing layer mixture includes the following materials in parts by weight: 7 parts of 32.5 grade ordinary Portland cement, 88 parts of stabilized materials and 5 parts of water. The stabilized materials include the following materials in parts by weight: 85 parts of clay-based recycled aggregate and 15 parts of washed sand. The particle grading of the clay-based recycled aggregate is: 0 parts of 10 mm particle size, 0 parts of 20 mm particle size, and 100 parts of 30 mm particle size. The fineness modulus of the washed sand is 2.2, and the mud content is 1.8%.

[0069] Among them, the clay-based recycled aggregate includes the following raw materials in parts by weight: 60 parts of engineering mud with a moisture content of 7%, 17.3 parts of 42.5-grade ordinary Portland cement, 6.7 parts of waste slag from the ceramic firing process, and 16 parts of tap water. The mud cake after the separation of mud and sand from the engineering mud is naturally dried and crushed to obtain powder. The particle size of the waste slag from the ceramic firing process is 1.18 mm. The raw materials of the clay-based recycled aggregate are weighed according to the designed ratio. The clay base material is weighed in two parts, and the mass percentages of the first and second parts are 70% and 30% respectively. The weighed cementitious material is added to the first part of the clay material and stirred. Then, the second part of the clay base material is added and the weighed external admixtures and water are added and stirred. The stirred mixture is added to the clay-based recycled aggregate extrusion molding equipment to extrude the clay-based recycled aggregate. The clay-based recycled aggregate is cured indoors. The aggregate produced by the extrusion molding equipment is as follows: Figure 1 As shown in the figure, the cylinder compressive strength of the clay-based recycled aggregate after 28 days of indoor curing is 3.0 MPa, the crushing index is 29%, and the water absorption rate is 9% in 1 hour; the cylinder compressive strength of the clay-based recycled aggregate after 28 days of water-immersion curing is 4.2 MPa, the crushing index is 26%, and the water absorption rate is 8% in 1 hour.

[0070] For road cement stabilization, the mixing method is as follows: First, mix 7 parts 32.5-grade ordinary Portland cement with 5 parts water to form a slurry. Then, add 88 parts of the stabilizing material (85 parts clay-based recycled aggregate and 15 parts washed sand) and mix thoroughly. The slurry is then added to the stabilizing material and mixed thoroughly to form a mixture. The mixture is then transported to the road construction site for cement stabilization. The 32.5-grade ordinary Portland cement used has an initial setting time of 4.5 hours and a final setting time of 6.2 hours. The cement stabilization layer has an unconfined compressive strength of 3.5 MPa after 7 days.

[0071] Example 4

[0072] The road water-stabilizing layer mixture in this embodiment includes the following materials in parts by weight: 11 parts of alkali-activated cementitious material, 81 parts of stabilized material and 8 parts of water. The activator is a sulfate activator, and the sulfate activator includes the following raw materials in parts by weight: 27 parts of quicklime powder, 67 parts of dihydrate gypsum, and 6 parts of sodium sulfate. The stabilized material includes the following materials in parts by weight: 75 parts of clay-based recycled aggregate and 25 parts of washed sand. The particle gradation of the clay-based recycled aggregate is: 50 parts of 10mm particle size, 30 parts of 20mm particle size, and 20 parts of 30mm particle size. The fineness modulus of the washed sand is 2.0, and the mud content is 1.6%.

[0073] Among them, the clay-based recycled aggregate includes the following raw materials in parts by weight: 60 parts of clay with a moisture content of 7%, 13.3 parts of 42.5-grade ordinary Portland cement, 6.7 parts of stone powder, and 20 parts of tap water. The mud cake after the separation of clay and sand is naturally dried and crushed to obtain powder. The stone powder is powder particles with a particle size of 0.074 mm produced during the concrete crushing process. The raw materials of the clay-based recycled aggregate are weighed according to the designed ratio. The clay base material is weighed in two parts, and the mass percentages of the first and second parts are 70% and 30% respectively. The weighed cementitious material is added to the first part of the clay material and stirred. Then, the second part of the clay base material is added and the weighed external admixtures and water are added and stirred. The stirred mixture is added to the clay-based recycled aggregate extrusion molding equipment to extrude the clay-based recycled aggregate. The clay-based recycled aggregate is cured indoors. The aggregate produced by the extrusion molding equipment is as follows: Figure 1 As shown in the figure, the cylinder compressive strength of the clay-based recycled aggregate after 28 days of indoor curing is 3.0 MPa, the crushing index is 28.7%, and the water absorption rate is 11% in 1 hour; the cylinder compressive strength of the clay-based recycled aggregate after 28 days of water-immersion curing is 4.9 MPa, the crushing index is 26.4%, and the water absorption rate is 9% in 1 hour.

[0074] When used in road stabilization layers, the mixing method is as follows: First, mix 11 parts alkali-activated cementitious material with 8 parts water to form a slurry. Then, evenly mix 81 parts (75 parts clay-based recycled aggregate and 25 parts washed sand) of the stabilized material. The slurry is then added to the stabilized material and mixed evenly to form a mixture. The mixture is then transported to the road construction site for the stabilization layer. The alkali-activated cementitious material has an initial setting time of 3.2 hours and a final setting time of 6.1 hours. The 7-day unconfined compressive strength of the stabilization layer is 4.5 MPa.

[0075] Example 5

[0076] In this embodiment, the road water-stabilizing layer mixture includes the following materials in parts by weight: 3 parts of alkali-activated cementitious material, 96 parts of stabilized material and 1 part of water. The activator is a sulfate activator, and the sulfate activator includes the following raw materials in parts by weight: 80 parts of quicklime powder, 0 parts of dihydrate gypsum, and 20 parts of sodium sulfate. The stabilized material includes the following materials in parts by weight: 95 parts of clay-based recycled aggregate and 5 parts of washed sand. The particle gradation of the clay-based recycled aggregate is: 45 parts of 10 mm particle size, 35 parts of 20 mm particle size, and 20 parts of 30 mm particle size. The fineness modulus of the washed sand is 2.0, and the mud content is 3.0%.

[0077] The clay-based recycled aggregate includes the following raw materials in parts by weight: 60 parts of engineering waste with a moisture content of 7%, 6.7 parts of 42.5-grade ordinary Portland cement, 13.3 parts of stone powder, and 20 parts of tap water. The engineering waste is the powder obtained by crushing the mud cake after the separation of engineering debris and sand and then drying it naturally. The stone powder is powder particles with a particle size of 0.074 mm produced during the concrete crushing process. The raw materials of the clay-based recycled aggregate are weighed according to the designed ratio. The clay base material is weighed in two parts, and the mass percentages of the first and second parts are 70% and 30% respectively. The weighed cementitious material is added to the first part of the clay material and stirred. Then, the second part of the clay base material is added and the weighed external admixtures and water are added and stirred. The stirred mixture is added to the clay-based recycled aggregate extrusion molding equipment to extrude the clay-based recycled aggregate. The clay-based recycled aggregate is cured indoors. The aggregate produced by the extrusion molding equipment is as follows: Figure 1 As shown in the figure, the cylinder compressive strength of the clay-based recycled aggregate after 28 days of indoor curing is 2.5 MPa, the crushing index is 25.9%, and the water absorption rate of 1h is 13%; the cylinder compressive strength of the clay-based recycled aggregate after 28 days of water-immersion curing is 3.6 MPa, the crushing index is 23.5%, and the water absorption rate of 1h is 11%.

[0078] For road cement stabilization, the mixing method is as follows: First, mix 3 parts 32.5-grade ordinary Portland cement with 1 part water to form a slurry. Then, evenly mix 96 parts of the stabilized material (95 parts clay-based recycled aggregate and 5 parts washed sand). The slurry is then added to the stabilized material and mixed thoroughly to form a mixture. The mixture is then transported to the road construction site for cement stabilization. The alkali-activated cementitious material used has an initial setting time of 4.2 hours and a final setting time of 6.3 hours. The unconfined compressive strength of the cement stabilization layer after 7 days is 3.2 MPa.

[0079] Example 6

[0080] The road water-stabilizing layer mixture in this embodiment includes the following materials in parts by weight: 7 parts of alkali-activated cementitious material, 88 parts of stabilized material and 5 parts of water. The activator is a sulfate activator, and the sulfate activator includes the following raw materials in parts by weight: 54 parts of quicklime powder, 33 parts of dihydrate gypsum, and 13 parts of sodium sulfate. The stabilized material includes the following materials in parts by weight: 85 parts of clay-based recycled aggregate and 15 parts of washed sand. The particle gradation of the clay-based recycled aggregate is: 55 parts of 10 mm particle size, 35 parts of 20 mm particle size, and 10 parts of 30 mm particle size. The fineness modulus of the washed sand is 2.2, and the mud content is 1.8%.

[0081] Among them, the clay-based recycled aggregate includes the following raw materials in parts by weight: 60 parts of engineering waste soil with a moisture content of 7%, 17.3 parts of 42.5-grade ordinary Portland cement, 6.7 parts of waste residue from the ceramic firing process, and 16 parts of tap water. The engineering waste soil is the mud cake obtained by natural drying and crushing after the separation of engineering waste soil and sand. The particle size of the waste residue from the ceramic firing process is 1.18 mm. The raw materials of the clay-based recycled aggregate are weighed according to the designed ratio. The clay base material is weighed in two parts, and the mass percentages of the first and second parts are 70% and 30% respectively. The weighed cementitious material is added to the first part of the clay material and stirred. Then, the second part of the clay base material is added and the weighed external admixtures and water are added and stirred. The stirred mixture is added to the clay-based recycled aggregate extrusion molding equipment to extrude the clay-based recycled aggregate. The clay-based recycled aggregate is cured indoors. The aggregate produced by the extrusion molding equipment is as follows: Figure 1 As shown in the figure, the cylinder compressive strength of the clay-based recycled aggregate after 28 days of indoor curing is 3.0 MPa, the crushing index is 29%, and the water absorption rate is 9% in 1 hour; the cylinder compressive strength of the clay-based recycled aggregate after 28 days of water-immersion curing is 4.2 MPa, the crushing index is 26%, and the water absorption rate is 8% in 1 hour.

[0082] For road cement stabilization, the mixing method is as follows: First, mix 7 parts 32.5-grade ordinary Portland cement with 5 parts water to form a slurry. Then, add 88 parts of the stabilized material (85 parts clay-based recycled aggregate and 15 parts washed sand) and mix thoroughly. The slurry is then added to the stabilized material and mixed thoroughly to form a mixture. The mixture is then transported to the road construction site for cement stabilization. The alkali-activated cementitious material used has an initial setting time of 4.3 hours and a final setting time of 6.5 hours. The unconfined compressive strength of the cement stabilization layer after 7 days is 3.9 MPa.

[0083] By applying clay-based recycled aggregate and washed sand to rural road construction, the level of solid waste resource utilization in water conservancy project construction and maintenance projects in plain rural areas has been effectively improved, and the dependence of plain rural areas on natural sand and gravel resources has been significantly reduced, providing technical support for the sustainable development and high-quality development of new rural road construction. The road water-stabilizing layer mixture and mixing method of the present invention not only provide a new type of road stabilized coarse aggregate, but also improve the mixing quality of the mixture, which is conducive to the high-quality development of road construction in plain rural areas and the improvement of new quality productivity.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading the specification of this application, technicians can still modify or replace the specific implementation methods of the present invention with equivalents, but these modifications or changes do not depart from the scope of protection of the pending claims of the present application.

Claims

1. A road water-stabilizing layer mixture, characterized in that: The road water-stabilizing layer mixture comprises the following materials by weight: 3 to 11 parts of a binder, 81 to 96 parts of a stabilized material, and 1 to 8 parts of water, wherein the binder is an alkali-activated cementitious material, and the stabilized material is a clay-based recycled aggregate and washed sand; The activator used in the alkali-activated gelling material is a sulfate activator; The sulfate activator comprises the following raw materials in parts by weight: 27 to 80 parts of quicklime powder, 6 to 20 parts of sodium sulfate, and 33 to 67 parts of dihydrate gypsum; The stabilized material includes the following materials by weight: 75-95 parts of clay-based recycled aggregate and 5-25 parts of washed sand; The clay-based recycled aggregate comprises the following raw materials in parts by weight: 50 to 96 parts of clay-based material and 4 to 56 parts of cementitious material; The clay base material is a powder obtained by naturally drying and then crushing the mud cake after separation of engineering debris and sand; The cementitious material is ordinary Portland cement; The clay-based recycled aggregate is ellipsoidal; The method for producing the clay-based recycled aggregate comprises the following steps: S1. Weigh the raw materials according to the designed ratio. The clay base material is weighed in two parts, with the mass percentages of the first and second parts being 70% and 30% respectively. Add the gelling material to the first part of the clay material and stir, then add the second part of the clay base material and water and stir; S2, adding the stirred mixture to a clay-based recycled aggregate extrusion molding device to extrude the clay-based recycled aggregate; S3. Carry out indoor curing, water immersion curing or carbonization curing on clay-based recycled aggregate.

2. A road water-stabilizing layer mixture according to claim 1, characterized in that: The washed sand is sand that is washed with water after the separation of engineering debris mud and sand, has a fineness modulus of 2.0 to 2.5, and a mud content of less than 3%.

3. A road water-stabilizing layer mixture according to claim 1, characterized in that: The particle gradation of the clay-based recycled aggregate is: 0 to 100 parts of 10 mm particle size, 0 to 100 parts of 20 mm particle size, and 0 to 100 parts of 30 mm particle size.

4. A road water-stabilizing layer mixture according to claim 1, characterized in that: The clay-based recycled aggregate further comprises the following parts by weight: 6.7 to 28 parts of raw mineral admixtures and 16 to 50 parts of water; The mineral admixture includes: one or more of waste residue and stone powder in the ceramic firing process; and the water is fresh water.

5. A road water-stabilizing layer mixture according to claim 1, characterized in that: The carbonization curing conditions of the clay-based recycled aggregate are: temperature of 3 to 48° C., relative humidity of 36 to 62%, and pressure of 0 to 2.8 MPa.

6. A road water-stabilizing layer mixture according to claim 1, characterized in that: The clay-based recycled aggregate has a 28-day cylinder compressive strength greater than 2 MPa, a crushing index less than 30%, and a 1-hour water absorption rate less than 20%.

7. The method for mixing a road water-stabilizing layer mixture according to any one of claims 1 to 6, characterized in that: The mixing method comprises the following steps: P1. Evenly mix the weighed binder and water into a slurry; P2. Mix the weighed stabilized materials evenly; P3, add the slurry in P1 to the stabilized material in P2 and stir evenly to form a mixture; P4. Transport the mixture in P3 to the road construction site for water-stabilizing layer construction.

8. A method for mixing road water-stabilizing layer mixture according to claim 7, characterized in that: The initial setting time of the binder is greater than 3 hours, the final setting time is 6 to 10 hours, and the unconfined compressive strength of the water-stabilizing layer 7d is 2 to 4.5 MPa.

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