Construction method of multi-element solid waste-based cementing material roadbed filler

Abstract

The invention provides a construction method of a multi-element solid waste-based cementing material roadbed filler, and relates to the technical field of road engineering, and the construction method comprises the following steps: S1, selecting raw materials: fly ash, slag powder, carbide slag powder, desulfurized gypsum powder, gasified slag powder, coal gangue powder, steel slag powder, tailing powder, coal cinder powder, building solid waste powder and municipal waste powder; s2, raw material pretreatment; s3, preparing a composite exciting agent: preparing sodium sulfate, calcium hydroxide, calcium chloride, calcium sulfate, sodium silicate and sodium hydroxide; s4, preparing a composite exciting agent solution; s5, preparing a multi-element solid waste-based cementing material: uniformly mixing the raw materials pretreated in the step S2 with the composite activator prepared in the step S4 according to a ratio; s6, roadbed laying, wherein a sodium bentonite waterproof blanket is laid on the bottom layer of the roadbed and then laid; s7, geogrids are laid; s8, maintenance is conducted; through fine selection and proportioning of the raw materials, efficient resource utilization of various industrial solid wastes is realized.

Description

Technical Field

[0001] The invention relates to the technical field of road engineering, and in particular to a construction method for a roadbed filler made of a multi-solid waste-based cementitious material. Background Art

[0002] Driven by the comprehensive utilization of solid waste and relevant policies on the development of circular economy, the resource utilization of bulk solid waste has become a hot topic and focus.

[0003] Inner Mongolia is rich in mineral resources, with a large amount of industrial solid waste. The storage takes up a lot of land space and has a high risk of pollution. The amount of various solid wastes has increased dramatically. How to deal with these solid wastes efficiently and environmentally friendly has become an urgent problem to be solved. Traditional solid waste treatment methods, such as landfill and incineration, not only occupy a lot of land resources, but also may cause secondary pollution to the environment. Therefore, exploring ways to utilize solid waste resources and achieve the reduction, harmlessness and resource utilization of solid waste has important practical significance and environmental value.

[0004] In the field of transportation infrastructure construction, roadbed fillers are indispensable materials. Traditional roadbed fillers mainly come from natural minerals, such as crushed stone, gravel, etc. The mining and transportation of these materials not only consume a lot of energy, but may also cause damage to the ecological environment. Therefore, converting solid waste into roadbed fillers can not only solve the problem of solid waste disposal, but also reduce the demand for traditional roadbed fillers and realize the recycling of resources.

[0005] However, there are still some problems in the current construction method of multi-solid waste based cementitious materials roadbed filler, such as insufficient pretreatment of raw materials, unreasonable ratio of composite activator, inadequate standardization of construction process, etc. These problems limit the application of multi-solid waste based cementitious materials roadbed filler in actual engineering. Therefore, it is necessary to optimize and improve the construction method of multi-solid waste based cementitious materials roadbed filler to improve its construction quality and engineering performance. Summary of the invention

[0006] In order to solve the above technical problems, the present invention proposes a construction method for a multi-solid waste-based cementitious material roadbed filler. Through fine raw material selection, pretreatment and proportioning, as well as reasonable composite activator preparation and construction process, efficient resource utilization of multi-solid waste is achieved, providing a new and environmentally friendly roadbed filler option for transportation infrastructure construction, as follows: A construction method for a multi-solid waste-based cementitious material roadbed filler comprises the following steps: S1. Raw material selection: by mass: 20-40 parts of fly ash, 10-30 parts of slag powder, 5-20 parts of calcium carbide slag powder, 3-10 parts of desulfurized gypsum powder, 5-15 parts of gasified slag powder, 10-25 parts of coal gangue powder, 10-20 parts of steel slag powder, 5-15 parts of tailings powder, 5-15 parts of coal slag powder, 3-5 parts of construction solid waste powder, and 3-5 parts of urban garbage powder; S2, raw material pretreatment: drying and grinding the raw materials in step S1; S3, preparation of composite activator: by mass, 5-15 parts of sodium sulfate, 10-25 parts of calcium hydroxide, 2-8 parts of calcium chloride, 5-10 parts of calcium sulfate, 10-20 parts of sodium silicate, and 2-5 parts of sodium hydroxide; S4, preparation of composite activator solution: adding 5-10 times the mass of water to the composite activator prepared in step S3 to form a composite activator solution; S5, multi-solid waste-based gelling material: the raw materials pretreated in step S2 and the composite activator prepared in step S4 are mixed uniformly at a mass ratio of raw materials: composite activator solution = 1:0.3-0.6 to obtain a multi-solid waste-based gelling material; S6. Roadbed paving: After laying the sodium-based bentonite waterproof blanket on the roadbed sub-base, mix the multi-solid waste-based cementitious material with water and lay it on the sodium-based bentonite waterproof blanket; S7. Geogrid laying: After the roadbed is completed, geogrid laying is carried out; S8. Maintenance.

[0007] Moreover, after the raw materials in step S2 are dried and ground, the particle size of the fly ash is 40-50μm, the particle size of the slag powder is 30-40μm, the particle size of the carbide slag powder is 10-20μm, the particle size of the desulfurized gypsum powder is 2-3mm, the particle size of the gasified slag powder, coal gangue powder, steel slag powder, the tailings powder, and coal slag powder is 20-30μm, and the particle size of the construction solid waste powder and urban garbage powder is 2-3mm.

[0008] Moreover, in step S6, the ratio of the multi-solid waste-based gelling material to water is 10:3-4.

[0009] Furthermore, in the step S6, when the multi-solid waste-based cementitious material is mixed with water and laid, horizontal filling and compaction are performed in layers.

[0010] Furthermore, in step S7, the geogrid is attached to the surface of the roadbed and fixed by U-shaped nails.

[0011] Moreover, in step S7, the transverse joints of the geogrid are staggered by a distance greater than or equal to 1 m.

[0012] Moreover, in the step S3, the composite activator is prepared by: by mass, 10 parts of sodium sulfate, 15 parts of calcium hydroxide, 5 parts of calcium chloride, 8 parts of calcium sulfate, 15 parts of sodium silicate, and 3 parts of sodium hydroxide.

[0013] Moreover, in the step S3, the composite activator is prepared by: by mass, 5 parts of sodium sulfate, 10 parts of calcium hydroxide, 2 parts of calcium chloride, 5 parts of calcium sulfate, 10 parts of sodium silicate, and 2 parts of sodium hydroxide.

[0014] Moreover, in the step S3, the composite activator is prepared by: by mass, 15 parts of sodium sulfate, 25 parts of calcium hydroxide, 8 parts of calcium chloride, 10 parts of calcium sulfate, 20 parts of sodium silicate, and 5 parts of sodium hydroxide.

[0015] Moreover, construction solid waste includes construction debris, waste mud, construction garbage, demolition waste, etc.; urban garbage includes waste plastics, waste metals, etc.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention realizes efficient resource utilization of various industrial solid wastes (such as fly ash, slag powder, carbide slag powder, etc.) through fine raw material selection and proportioning, which not only solves the problem of solid waste disposal, but also reduces the demand for traditional roadbed fillers (such as natural ore, gravel), and reduces energy consumption and ecological damage during mining and transportation. Compared with traditional solid waste treatment methods (such as landfill and incineration), the method of the present invention has higher environmental value, can effectively reduce land occupation and reduce the risk of secondary pollution.

[0017] 2. The present invention ensures the stable and reliable performance of multi-solid waste-based cementitious materials through reasonable composite activator preparation and construction technology. The addition of composite activators can stimulate the activity of solid waste materials and improve the strength and stability of cementitious materials. At the same time, during the construction process, the present invention adopts layered horizontal filling and layered compaction methods to ensure the uniformity and density of the roadbed filler, thereby improving the bearing capacity and durability of the roadbed.

[0018] 4. The method of the present invention can utilize a large amount of industrial solid waste as roadbed filler, which can significantly reduce the cost of raw materials. At the same time, due to the optimization of construction technology and the improvement of engineering performance, it can also reduce waste and rework in the construction process, further reducing construction costs.

[0019] 5. The method of the present invention is in line with the national policy orientation on waste recycling and green transformation, and will help promote the comprehensive utilization of bulk solid waste and the realization of carbon peak and carbon neutrality goals. Through the implementation of the present invention, it can provide a new and environmentally friendly roadbed filling option for the field of transportation infrastructure construction, which has important demonstration effect and promotion value.

[0020] 6. The composite activator provided by the present invention can activate the potential active ingredients in various industrial solid wastes through reasonable formula selection and ratio, so that the solid waste that was originally difficult to utilize can be converted into high-performance building materials. The utilization rate of solid waste is significantly improved, the mining and consumption of traditional building materials are reduced, and it is helpful to protect natural resources and the ecological environment.

[0021] 7. The composite activator provided by the present invention can significantly improve the strength, stability and durability of multi-solid waste-based cementitious materials, so that they can maintain good performance during long-term use, help extend the service life of roads, reduce repair and maintenance costs, and improve the efficiency and safety of transportation.

[0022] 8. The composite activator provided by the present invention can promote chemical reactions between solid waste components to form a more stable chemical bonding structure. This chemical bonding structure helps to improve the overall performance and stability of the material, making it more durable during use. DETAILED DESCRIPTION

[0023] Example 1 A construction method for a multi-solid waste-based cementitious material roadbed filler, comprising the following steps S1. Raw materials selection: by mass: 20 parts of fly ash, 10 parts of slag powder, 5 parts of calcium carbide slag powder, 3 parts of desulfurized gypsum powder, 5 parts of gasified slag powder, 10 parts of coal gangue powder, 10 parts of steel slag powder, 5 parts of tailings powder, 5 parts of coal slag powder, 3 parts of construction solid waste powder, and 3 parts of urban garbage powder; S2, raw material pretreatment: drying and grinding the raw materials in step S1; S3, composite activator preparation: by mass, 5 parts of sodium sulfate, 10 parts of calcium hydroxide, 2 parts of calcium chloride, 5 parts of calcium sulfate, 10 parts of sodium silicate, and 2 parts of sodium hydroxide; S4, preparation of composite activator solution: adding 5 times the mass of water to the composite activator prepared in step S3 to form a composite activator solution; S5, multi-solid waste-based gelling material: the raw materials pretreated in step S2 and the composite activator prepared in step S4 are mixed uniformly at a mass ratio of raw materials: composite activator solution = 1:0.3 to obtain a multi-solid waste-based gelling material; S6. Roadbed paving: After laying the sodium-based bentonite waterproof blanket on the roadbed bottom layer, mix the multi-solid waste-based cementitious material with water and lay it on the sodium-based bentonite waterproof blanket; S7. Geogrid laying: After the roadbed is completed, geogrid laying is carried out; S8. Maintenance.

[0024] Furthermore, after the raw materials in step S2 are dried and ground, the particle size of the fly ash is 40 μm, the particle size of the slag powder is 30 μm, the particle size of the carbide slag powder is 10 μm, the particle size of the desulfurized gypsum powder is 2 mm, the particle size of the gasified slag powder, coal gangue powder, steel slag powder, the tailings powder, and coal slag powder is 20 μm, and the particle size of the construction solid waste powder and urban garbage powder is 2 mm.

[0025] Furthermore, in step S6, the ratio of the multi-solid waste-based gelling material to water is 10:3-4.

[0026] Furthermore, in step S6, when the multi-solid waste-based cementitious material is mixed with water and laid, it is horizontally filled and compacted in layers.

[0027] Furthermore, in step S7, the geogrid is attached to the surface of the roadbed and fixed by U-shaped nails.

[0028] Furthermore, in step S7, the transverse joints of the geogrid are staggered by a distance greater than or equal to 1 m.

[0029] Example 2 A construction method for a multi-solid waste-based cementitious material roadbed filler, comprising the following steps S1. Raw materials selection: by mass: 40 parts of fly ash, 30 parts of slag powder, 20 parts of calcium carbide slag powder, 10 parts of desulfurized gypsum powder, 15 parts of gasified slag powder, 25 parts of coal gangue powder, 20 parts of steel slag powder, 15 parts of tailings powder, 15 parts of coal slag powder, 5 parts of construction solid waste powder, and 5 parts of urban garbage powder; S2, raw material pretreatment: drying and grinding the raw materials in step S1; S3, composite activator preparation: by mass, 15 parts of sodium sulfate, 25 parts of calcium hydroxide, 8 parts of calcium chloride, 10 parts of calcium sulfate, 20 parts of sodium silicate, 5 parts of sodium hydroxide; S4, preparation of composite activator solution: adding 10 times the mass of water to the composite activator prepared in step S3 to form a composite activator solution; S5, multi-solid waste-based gelling material: the raw materials pretreated in step S2 and the composite activator prepared in step S4 are mixed uniformly at a mass ratio of raw materials: composite activator solution = 1:0.6 to obtain a multi-solid waste-based gelling material; S6. Roadbed paving: After laying the sodium-based bentonite waterproof blanket on the roadbed sub-base, mix the multi-solid waste-based cementitious material with water and lay it on the sodium-based bentonite waterproof blanket; S7. Geogrid laying: After the roadbed is completed, geogrid laying is carried out; S8. Maintenance.

[0030] Furthermore, after the raw materials in step S2 are dried and ground, the particle size of the fly ash is 50 μm, the particle size of the slag powder is 40 μm, the particle size of the carbide slag powder is 20 μm, the particle size of the desulfurized gypsum powder is 3 mm, the particle size of the gasified slag powder, coal gangue powder, steel slag powder, the tailings powder, and coal slag powder is 30 μm, and the particle size of the construction solid waste powder and urban garbage powder is 3 mm.

[0031] Furthermore, in step S6, the ratio of the multi-solid waste-based gelling material to water is 10:4.

[0032] Furthermore, in step S6, when the multi-solid waste-based cementitious material is mixed with water and laid, it is horizontally filled and compacted in layers.

[0033] Furthermore, in step S7, the geogrid is attached to the surface of the roadbed and fixed by U-shaped nails.

[0034] Furthermore, in step S7, the transverse joints of the geogrid are staggered by a distance greater than or equal to 1 m.

[0035] Example 3 A construction method for a multi-solid waste-based cementitious material roadbed filler, comprising the following steps S1. Raw material selection: by mass: 30 parts of fly ash, 20 parts of slag powder, 12 parts of calcium carbide slag powder, 6 parts of desulfurized gypsum powder, 10 parts of gasified slag powder, 18 parts of coal gangue powder, 15 parts of steel slag powder, 10 parts of tailings powder, 10 parts of coal slag powder, 4 parts of construction solid waste powder, and 4 parts of urban garbage powder; S2, raw material pretreatment: drying and grinding the raw materials in step S1; S3, composite activator preparation: by mass: 10 parts of sodium sulfate, 15 parts of calcium hydroxide, 5 parts of calcium chloride, 8 parts of calcium sulfate, 15 parts of sodium silicate, and 3 parts of sodium hydroxide; S4, preparation of composite activator solution: adding 8 times the mass of water to the composite activator prepared in step S3 to form a composite activator solution; S5, multi-solid waste-based gelling material: the raw materials pretreated in step S2 and the composite activator prepared in step S4 are mixed uniformly at a mass ratio of raw materials: composite activator solution = 1:0.45 to obtain a multi-solid waste-based gelling material; S6. Roadbed paving: After laying the sodium-based bentonite waterproof blanket on the roadbed bottom layer, mix the multi-solid waste-based cementitious material with water and lay it on the sodium-based bentonite waterproof blanket; S7. Geogrid laying: After the roadbed is completed, geogrid laying is carried out; S8. Maintenance.

[0036] Furthermore, after the raw materials in step S2 are dried and ground, the particle size of the fly ash is 45 μm, the particle size of the slag powder is 35 μm, the particle size of the carbide slag powder is 15 μm, the particle size of the desulfurized gypsum powder is 2.5 mm, the particle size of the gasified slag powder, coal gangue powder, steel slag powder, the tailings powder, and coal slag powder is 25 μm, and the particle size of the construction solid waste powder and urban garbage powder is 2.5 mm.

[0037] Furthermore, in step S6, the ratio of the multi-solid waste-based gelling material to water is 10:3.5.

[0038] Furthermore, in step S6, when the multi-solid waste-based cementitious material is mixed with water and laid, it is horizontally filled and compacted in layers.

[0039] Furthermore, in step S7, the geogrid is attached to the surface of the roadbed and fixed by U-shaped nails.

[0040] Furthermore, in step S7, the transverse joints of the geogrid are staggered by a distance greater than or equal to 1 m.

[0041] Comparative Example 1 The difference between this comparative example and Example 3 is that in step S3, no sodium sulfate is added when the composite activator is prepared.

[0042] Comparative Example 2 The difference between this comparative example and Example 3 is that in step S3, no calcium hydroxide is added when the composite activator is prepared.

[0043] Comparative Example 3 The difference between this comparative example and Example 3 is that in step S3, no calcium chloride is added when the composite activator is prepared.

[0044] Comparative Example 4 The difference between this comparative example and Example 3 is that in step S3, no calcium sulfate is added when the composite activator is prepared.

[0045] Comparative Example 5 The difference between this comparative example and Example 3 is that in step S3, no sodium silicate is added when the composite activator is prepared.

[0046] Comparative Example 6 The difference between this comparative example and Example 3 is that in step S3, no sodium hydroxide is added when the composite activator is prepared.

[0047] Experimental Section The roadbed constructed by the methods of Examples 1-3 and Comparative Examples 1-6 was tested for strength, stability and durability, and the results were recorded and analyzed. The compressive strength was tested according to the national standard GB / T50123-2019 "Geotechnical Engineering Test Code"; the deformation resistance was measured by the Beckman beam test method; the water resistance strength loss rate was tested according to the "Technical Specifications for Highway Roadbed Construction"; The test method for weather resistance strength loss rate is as follows: 1. Randomly sample the roadbed to be tested, use a universal testing machine to test the strength of the specimen, and record the initial strength value; 2. Simulate the climate, load and other conditions in the actual environment and conduct accelerated aging or long-term exposure experiments on the specimens; 3. After the aging or exposure test, perform strength test on the specimen again and record the strength value after aging; 4. Calculate the strength loss rate based on the initial strength value and the strength value after aging: Strength loss rate = (initial strength - strength after aging) / initial strength × 100%.

[0048] The results are shown in Table 1 below: Table 1 Roadbed test results

[0049] It can be seen from the above experiments that the strength, stability and durability of the roadbed constructed using the technical solution of the present invention are better than those of the control example, which proves that the construction using the technical solution of the present invention has a significant improvement in the performance of the roadbed. This is because the addition of the composite activator of the present invention can promote the chemical reaction between the solid waste components to form a more stable chemical bonding structure. This chemical bonding structure helps to improve the overall performance and stability of the material, so that it has better durability during use, can improve the compressive strength and deformation resistance of the roadbed, reduce the water resistance strength loss rate and weather resistance strength loss rate, and further extend the service life of the roadbed.

Claims

1. A construction method for roadbed filler made of multi-solid waste-based cementitious materials, characterized in that: The steps include: S1. Raw material selection: by mass: 20-40 parts of fly ash, 10-30 parts of slag powder, 5-20 parts of calcium carbide slag powder, 3-10 parts of desulfurized gypsum powder, 5-15 parts of gasified slag powder, 10-25 parts of coal gangue powder, 10-20 parts of steel slag powder, 5-15 parts of tailings powder, 5-15 parts of coal slag powder, 3-5 parts of construction solid waste powder, and 3-5 parts of urban garbage powder; S2, raw material pretreatment: drying and grinding the raw materials in step S1; S3, preparation of composite activator: by mass, 5-15 parts of sodium sulfate, 10-25 parts of calcium hydroxide, 2-8 parts of calcium chloride, 5-10 parts of calcium sulfate, 10-20 parts of sodium silicate, and 2-5 parts of sodium hydroxide; S4, preparation of composite activator solution: adding 5-10 times the mass of water to the composite activator prepared in step S3 to form a composite activator solution; S5, multi-solid waste-based gelling material: the raw materials pretreated in step S2 and the composite activator prepared in step S4 are mixed uniformly at a mass ratio of raw materials: composite activator solution = 1:0.3-0.6 to obtain a multi-solid waste-based gelling material; S6. Roadbed paving: After laying the sodium-based bentonite waterproof blanket on the roadbed sub-base, mix the multi-solid waste-based cementitious material with water and lay it on the sodium-based bentonite waterproof blanket; S7. Geogrid laying: After the roadbed is completed, geogrid laying is carried out; S8. Maintenance.

2. A construction method for a multi-solid waste-based cementitious material roadbed filler as claimed in claim 1, characterized in that: After the raw materials in step S2 are dried and ground, the particle size of the fly ash is 40-50μm, the particle size of the slag powder is 30-40μm, the particle size of the carbide slag powder is 10-20μm, the particle size of the desulfurized gypsum powder is 2-3mm, the particle size of the gasified slag powder, coal gangue powder, steel slag powder, the tailings powder, and coal slag powder is 20-30μm, and the particle size of the construction solid waste powder and urban garbage powder is 2-3mm.

3. A construction method for a multi-solid waste-based cementitious material roadbed filler as claimed in claim 1, characterized in that: In step S6, the ratio of the multi-solid waste-based gelling material to water is 10:3-4.

4. A construction method for a multi-solid waste-based cementitious material roadbed filler as claimed in claim 3, characterized in that: In step S6, when the multi-solid waste-based cementitious material is mixed with water and laid, horizontal filling and compaction are performed in layers.

5. The method for constructing a multi-solid waste-based cementitious material roadbed filler as claimed in claim 1, characterized in that: In step S7, the geogrid is attached to the surface of the roadbed and fixed by U-shaped nails.

6. A construction method for roadbed filling material of multi-solid waste-based cementitious materials as claimed in claim 1, characterized in that: In step S7, the transverse joints of the geogrid are staggered by a distance greater than or equal to 1 m.

7. A construction method for roadbed filling material of multi-solid waste-based cementitious materials as claimed in claim 1, characterized in that: In step S3, the composite activator is prepared by: by mass, 10 parts of sodium sulfate, 15 parts of calcium hydroxide, 5 parts of calcium chloride, 8 parts of calcium sulfate, 15 parts of sodium silicate, and 3 parts of sodium hydroxide.

8. A construction method for a multi-solid waste-based cementitious material roadbed filler as claimed in claim 1, characterized in that: In step S3, the composite activator is prepared by: by mass, 5 parts of sodium sulfate, 10 parts of calcium hydroxide, 2 parts of calcium chloride, 5 parts of calcium sulfate, 10 parts of sodium silicate, and 2 parts of sodium hydroxide.

9. A construction method for roadbed filling material of multi-solid waste-based cementitious materials as claimed in claim 1, characterized in that: In step S3, the composite activator is prepared by: by mass, 15 parts of sodium sulfate, 25 parts of calcium hydroxide, 8 parts of calcium chloride, 10 parts of calcium sulfate, 20 parts of sodium silicate, and 5 parts of sodium hydroxide.

Images