A solid waste-based grouting material for road repair and its preparation method

Abstract

This invention proposes a solid waste-based grouting material for road repair and its preparation method, belonging to the field of comprehensive utilization technology of solid waste. The solid waste-based grouting material for road repair comprises, by weight, 20-40 parts of waste concrete fine powder, 10-40 parts of fly ash, 30-80 parts of blast furnace slag, 10-30 parts of red mud, 15-25 parts of waste iron filings, 20-33 parts of titanium slag, 3-8 parts of early-strength agent, 2-4 parts of water-reducing agent, 5-6 parts of expansion agent, and 1-4 parts of composite admixture. The titanium slag and waste iron filings are mixed, then hydrochloric acid is added, followed by aeration and heating aging to obtain filtrate and filter residue. The filter residue is mixed evenly with the remaining raw materials, and then water and filtrate are added to obtain the grouting material. The grouting material of this invention has the advantages of short setting time, excellent mechanical properties, corrosion resistance, and freeze resistance, while simultaneously solving the problem of low recycling efficiency of industrial and construction solid waste.

Description

Technical Field

[0001] This invention belongs to the field of comprehensive utilization technology of solid waste, and in particular relates to a solid waste-based grouting material for road repair and its preparation method. Background Technology

[0002] Due to repeated traffic loads and the influence of environmental factors such as temperature changes, humidity, and chemical erosion, the roadbed and base structure gradually suffer damage over long-term use. This damage manifests as uneven subgrade settlement, voids in the base material, and pavement heave, among other defects. These defects not only affect the service life of the road but may also lead to a decrease in pavement structural strength, increasing traffic safety hazards and reducing road efficiency. To minimize economic losses and improve socio-economic benefits, rapid pavement repair, while minimizing traffic disruption time, has become a top priority in pavement technology development.

[0003] Currently, the most commonly used road repair materials are silicate cement, which is mixed with aggregates to form mortar or concrete. Although it is low in cost, it has problems such as low bonding strength, low adhesion strength, and long setting time. On the other hand, commonly used organic grouting materials have good fluidity, strong adhesion, and fast hardening, but they are expensive, prone to aging, not resistant to high temperatures, and have poor compatibility with old concrete. In addition, many organic grouting materials are toxic and can pollute the surrounding groundwater.

[0004] With the acceleration of industrialization and urbanization, the output of industrial and construction solid waste has accumulated year by year, and the types of solid waste are numerous. The accumulation of large amounts of solid waste has led to many disastrous problems, including environmental pollution and ecological damage. If it is not treated and utilized in a timely manner, it will inevitably have adverse effects on society, the environment, and resources. Industrial and construction solid waste can be reused. For example, it can be crushed and mixed with sand and gravel for use as paving in ground gaps or molded into bricks, reducing the pollution and waste of resources caused by direct disposal of waste. However, existing solid waste treatment methods still face the problem of low utilization efficiency.

[0005] Therefore, this invention proposes a solid waste-based grouting material for road repair and its preparation method. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention proposes a solid waste-based grouting material for road repair and its preparation method.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] One of the technical solutions of the present invention:

[0009] A solid waste-based grouting material for road repair, by weight, comprises the following raw materials: 20-40 parts of waste concrete fine powder, 10-40 parts of fly ash, 30-80 parts of blast furnace slag, 10-30 parts of red mud, 15-25 parts of waste iron filings, 20-33 parts of titanium slag, 3-8 parts of early strength agent, 2-4 parts of water-reducing agent, 5-6 parts of expansion agent, and 1-4 parts of composite admixture.

[0010] Furthermore, the particle size of the waste concrete powder, fly ash, and blast furnace slag is all less than 0.2 mm.

[0011] Furthermore, the particle size of both the waste iron filings and titanium slag is less than 0.3 mm.

[0012] Furthermore, the specific surface area of ​​the red mud is 150–250 m². 2 / kg.

[0013] Furthermore, the molar ratio of Ca to Fe in the waste concrete fine powder is (2-3):1.

[0014] Furthermore, the waste iron filings are an iron-carbon mixture, wherein the mass ratio of iron to carbon is (1-3):1.

[0015] Furthermore, the early strength agent is one or more of calcium chloride, calcium sulfate, sodium aluminate, and sodium nitrite.

[0016] Furthermore, the water-reducing agent is a lignin sulfonate or a melamine-based water-reducing agent.

[0017] Furthermore, the expanding agent is an alum stone expanding agent or a calcium sulfoaluminate expanding agent.

[0018] Furthermore, the composite additive is composed of disodium hydrogen phosphate and borax mixed in a weight ratio of (3-4):1.

[0019] Preferably, the solid waste-based grouting material for road repair comprises, by weight, the following raw materials: 33 parts waste concrete powder, 25 parts fly ash, 63 parts blast furnace slag, 18 parts red mud, 20 parts waste iron filings, 26 parts titanium slag, 4 parts early strength agent, 3 parts water-reducing agent, 6 parts expansion agent, and 2 parts composite admixture.

[0020] The second technical solution of the present invention:

[0021] A method for preparing the solid waste-based grouting material for road repair includes the following steps:

[0022] Weigh each raw material according to the specified weight proportions, mix titanium slag and waste iron filings, then add hydrochloric acid and aerate to obtain a reaction material. After heating and aging the reaction material, obtain filtrate and filter residue. Mix the filter residue with red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture evenly to obtain a mixture. Then add the filtrate and water and mix evenly to obtain the solid waste-based grouting material for road repair.

[0023] Furthermore, the amount of hydrochloric acid added is 1 to 3 times the total mass of titanium slag and scrap iron, and the concentration of hydrochloric acid is 1 to 3 mol / L.

[0024] Furthermore, the aeration flow rate is 1–3 m³ / s. 3 / min, and the aeration time is >0.5 hours.

[0025] Furthermore, the heating and aging treatment is carried out at a temperature of 95–100°C for 2–4 hours.

[0026] Furthermore, the amount of water added is 20-40% of the total mass of the mixture, and the amount of filtrate added is 5-20% of the total mass of the mixture.

[0027] The technical principle of this invention is as follows:

[0028] This invention first mixes titanium slag and scrap iron, then adds hydrochloric acid and aerates the mixture to obtain a reaction material. After heating and aging the reaction material, filtrate and filter residue are obtained. Under acidic and aerated conditions, the titanium in the titanium slag exists as TiOCl2. Further heating and aging forms TiO2 adhering to the surface of the filter residue, thus giving the raw material filter residue a larger specific surface area and providing more contact points, thereby accelerating the setting time of the grouting material. The scrap iron contains iron and carbon. Under the influence of the electrode difference between iron and carbon, combined with aeration, the Fe content increases. 2+ It is rapidly oxidized to Fe 3+ The Ca in the filtrate is present in the filtrate. During the mixing process of the filtrate with waste concrete fine powder, fly ash, and blast furnace slag, the Ca in the waste concrete fine powder, fly ash, and blast furnace slag is also present. 2+ Fe in the filtrate 3+A calcium-iron layered double hydroxide is formed through a co-precipitation method. This calcium-iron layered double hydroxide can act as a nanobridge to bind the grouting material and soil colloid. This structure ensures the stability and synergistic fixation of the grouting material. In road repair, this stability helps improve the bonding force between the grouting material and the roadbed, thereby enhancing the overall stability and durability of the road. In addition, solid waste materials such as red mud, fly ash, and blast furnace slag, under the action of various admixtures, can promote hydration reactions, generating more hydration products and forming more gel mixtures such as CSH, CAH, and CASH, improving the strength and stability of the grout. This invention, through the rational combination of these solid waste materials and admixtures, can significantly improve the durability of solid waste-based grouting materials for road repair, thereby improving the quality and durability of road repair.

[0029] Compared with the prior art, the present invention has the following advantages and technical effects:

[0030] (1) The road repair solid waste-based grouting material of the present invention contains a variety of solid wastes, including waste concrete fine powder, fly ash, blast furnace slag, red mud, waste iron filings and titanium slag, which solves the problem of low recycling efficiency of industrial solid waste and construction solid waste and saves material preparation costs.

[0031] (2) The solid waste-based grouting material for road repair prepared by the present invention has the advantages of short setting time, excellent mechanical properties, corrosion resistance and freeze resistance. It can be widely used in grouting fields such as highway repair and reinforcement. It can not only efficiently solve the problems of insufficient bearing capacity of the original roadbed and serious damage to the roadbed and base structure, but also dispose of solid waste in large quantities and alleviate ecological and environmental pollution problems. Detailed Implementation

[0032] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0033] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0034] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0035] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0036] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0037] This invention provides a solid waste-based grouting material for road repair, comprising the following raw materials by weight: 20-40 parts of waste concrete fine powder, 10-40 parts of fly ash, 30-80 parts of blast furnace slag, 10-30 parts of red mud, 15-25 parts of waste iron filings, 20-33 parts of titanium slag, 3-8 parts of early-strength agent, 2-4 parts of water-reducing agent, 5-6 parts of expansion agent, and 1-4 parts of composite admixture.

[0038] In a preferred embodiment of the present invention, the particle size of the waste concrete powder, fly ash and blast furnace slag is all less than 0.2 mm.

[0039] In a preferred embodiment of the present invention, the particle size of both the waste iron filings and titanium slag is less than 0.3 mm.

[0040] In a preferred embodiment of the present invention, the specific surface area of ​​the red mud is 150–250 m². 2 / kg, moisture content ≤10%, pH value ≥10.

[0041] In a preferred embodiment of the present invention, the molar ratio of Ca to Fe in the waste concrete powder is (2-3):1. For example, the molar ratio of Ca to Fe in the waste concrete powder used in the embodiment of the present invention is measured to be 2:1.

[0042] In a preferred embodiment of the present invention, the waste iron scrap is an iron-carbon mixture, wherein the mass ratio of iron to carbon is (1-3):1. For example, it has been determined that the mass ratio of iron to carbon in the waste iron scrap used in the embodiment of the present invention is 1.8:1.

[0043] In a preferred embodiment of the present invention, the early strength agent is one or more of calcium chloride, calcium sulfate, sodium aluminate and sodium nitrite.

[0044] In a preferred embodiment of the present invention, the water-reducing agent is a lignin sulfonate or a melamine-based water-reducing agent. For example, the lignin sulfonate used in the embodiments of the present invention is calcium lignin sulfonate, and the melamine-based water-reducing agent used is melamine sulfonate formaldehyde resin.

[0045] In a preferred embodiment of the present invention, the expanding agent is alum stone expanding agent or calcium sulfoaluminate expanding agent.

[0046] In a preferred embodiment of the present invention, the composite additive is a mixture of disodium hydrogen phosphate and borax in a weight ratio of (3-4):1.

[0047] In a preferred embodiment of the present invention, the solid waste-based grouting material for road repair comprises, by weight, the following raw materials: 33 parts of waste concrete powder, 25 parts of fly ash, 63 parts of blast furnace slag, 18 parts of red mud, 20 parts of waste iron filings, 26 parts of titanium slag, 4 parts of early strength agent, 3 parts of water-reducing agent, 6 parts of expansion agent, and 2 parts of composite admixture.

[0048] This invention also provides a method for preparing the aforementioned solid waste-based grouting material for road repair, comprising the following steps:

[0049] Weigh each raw material according to the specified weight proportions, mix titanium slag and waste iron filings, then add hydrochloric acid and aerate to obtain a reaction material. After heating and aging the reaction material, obtain filtrate and filter residue. Mix the filter residue with red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture evenly to obtain a mixture. Then add the filtrate and water and mix evenly to obtain the solid waste-based grouting material for road repair.

[0050] In a preferred embodiment of the present invention, the amount of hydrochloric acid added is 1 to 3 times the total mass of titanium slag and scrap iron, and the concentration of hydrochloric acid is 1 to 3 mol / L.

[0051] In a preferred embodiment of the present invention, the aeration flow rate is 1-3 m³ / h. 3 / min, and the aeration time is >0.5 hours.

[0052] In a preferred embodiment of the present invention, the temperature of the heating and aging treatment is 95-100°C, and the time is 2-4 hours.

[0053] In a preferred embodiment of the present invention, the amount of water added is 20-40% of the total mass of the mixture, and the amount of filtrate added is 5-20% of the total mass of the mixture.

[0054] All raw materials used in the embodiments of this invention were commercially available. Specifically, waste concrete powder, fly ash, and blast furnace slag were ground to a particle size of less than 0.2 mm; waste iron filings and titanium slag were ground to a particle size of less than 0.3 mm; and red mud was ground to a specific surface area of ​​200 m². 2 / kg, moisture content = 15.3%, pH value = 12, ready for use; the mass ratio of iron to carbon in the scrap iron is 1.8:1, and the molar ratio of Ca to Fe in the waste concrete powder is 2:1.

[0055] In the embodiments of this invention, unless otherwise specified, "parts" refers to "number of parts by weight".

[0056] The technical solution of the present invention will be further illustrated by the following embodiments.

[0057] Example 1

[0058] A method for preparing a solid waste-based grouting material for road repair includes the following steps:

[0059] Weigh the following raw materials according to the following weight proportions: 33 parts waste concrete fine powder, 25 parts fly ash, 63 parts blast furnace slag, 18 parts red mud, 20 parts waste iron filings, 26 parts titanium slag, 4 parts early strength agent (calcium chloride), 3 parts water reducing agent (calcium lignosulfonate), 6 parts expansion agent (calcium sulfoaluminate expansion agent), and 2 parts composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 3:1).

[0060] Titanium slag and scrap iron were mixed, then 2 mol / L hydrochloric acid was added and aerated. The amount of hydrochloric acid added was twice the total mass of the titanium slag and scrap iron, and the aeration flow rate was 1.5 m³ / h. 3 The aeration rate is 1 min, and the aeration time is 1 hour to obtain the reaction material. The reaction material is heated and aged at 98℃ for 2.5 hours to obtain filtrate and filter residue. The filter residue is mixed evenly with red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture to obtain a mixture. Then, the filtrate (10% of the total mass of the mixture) and water (38% of the total mass of the mixture) are added and mixed evenly to obtain solid waste-based grouting material for road repair.

[0061] Example 2

[0062] A method for preparing a solid waste-based grouting material for road repair includes the following steps:

[0063] Weigh the following raw materials according to the following weight proportions: 40 parts waste concrete fine powder, 10 parts fly ash, 80 parts blast furnace slag, 10 parts red mud, 25 parts waste iron filings, 20 parts titanium slag, 3 parts early strength agent (calcium sulfate), 4 parts water reducing agent (melamine sulfonate formaldehyde resin), 6 parts expansion agent (calcium sulfoaluminate expansion agent), and 1 part composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 4:1).

[0064] Titanium slag and scrap iron were mixed, then 3 mol / L hydrochloric acid was added and aerated. The amount of hydrochloric acid added was equal to the total mass of the titanium slag and scrap iron, and the aeration flow rate was 3 m³ / h. 3 The aeration rate is 1 / min, and the aeration time is 1.5 hours to obtain the reaction material. The reaction material is heated and aged at 100℃ for 2 hours to obtain filtrate and filter residue. The filter residue is mixed evenly with red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture to obtain a mixture. Then, filtrate (20% of the total mass of the mixture) and water (40% of the total mass of the mixture) are added and mixed evenly to obtain solid waste-based grouting material for road repair.

[0065] Example 3

[0066] A method for preparing a solid waste-based grouting material for road repair includes the following steps:

[0067] Weigh the following raw materials according to the following weight proportions: 20 parts waste concrete fine powder, 40 parts fly ash, 30 parts blast furnace slag, 30 parts red mud, 15 parts waste iron filings, 33 parts titanium slag, 8 parts early strength agent (sodium aluminate), 2 parts water reducing agent (calcium lignosulfonate), 5 parts expansion agent (alum stone expansion agent), and 4 parts composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 3:1).

[0068] Titanium slag and scrap iron were mixed, then 1 mol / L hydrochloric acid was added and aerated. The amount of hydrochloric acid added was three times the total mass of the titanium slag and scrap iron, and the aeration flow rate was 1 m³ / s. 3 The aeration rate is 1 min, and the aeration time is 1 hour to obtain the reaction material. The reaction material is heated and aged at 95℃ for 4 hours to obtain filtrate and filter residue. The filter residue is mixed evenly with red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture to obtain a mixture. Then, filtrate (5% of the total mass of the mixture) and water (20% of the total mass of the mixture) are added and mixed evenly to obtain solid waste-based grouting material for road repair.

[0069] Example 4

[0070] A method for preparing a solid waste-based grouting material for road repair includes the following steps:

[0071] Weigh the following raw materials according to the following proportions by weight: 33 parts waste concrete fine powder, 22 parts fly ash, 74 parts blast furnace slag, 12 parts red mud, 20 parts waste iron filings, 28 parts titanium slag, 4 parts early strength agent (sodium nitrite), 3 parts water reducing agent (melamine sulfonate formaldehyde resin), 5 parts expansion agent (calcium sulfoaluminate expansion agent), and 2 parts composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 3:1).

[0072] Titanium slag and scrap iron were mixed, then 2 mol / L hydrochloric acid was added and aerated. The amount of hydrochloric acid added was twice the total mass of the titanium slag and scrap iron, and the aeration flow rate was 1.5 m³ / h. 3 The aeration rate is 1000 m / min, and the aeration time is 2 hours to obtain the reaction material. The reaction material is heated and aged at 99°C for 3 hours to obtain filtrate and filter residue. The filter residue is mixed evenly with red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture to obtain a mixture. Then, the filtrate (6% of the total mass of the mixture) and water (36% of the total mass of the mixture) are added and mixed evenly to obtain solid waste-based grouting material for road repair.

[0073] Comparative Example 1

[0074] A method for preparing a solid waste-based grouting material for road repair includes the following steps:

[0075] Weigh the following raw materials according to the following weight proportions: 33 parts waste concrete fine powder, 25 parts fly ash, 63 parts blast furnace slag, 18 parts red mud, 20 parts waste iron filings, 26 parts titanium slag, 4 parts early strength agent (calcium chloride), 3 parts water reducing agent (calcium lignosulfonate), 6 parts expansion agent (calcium sulfoaluminate expansion agent), and 2 parts composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 3:1).

[0076] Titanium slag, waste iron filings, red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture are mixed evenly to obtain a mixture. Then water (48% of the total mass of the mixture) is added and mixed evenly to obtain a solid waste-based grouting material for road repair.

[0077] Comparative Example 2

[0078] A method for preparing a solid waste-based grouting material for road repair, similar to Example 1, except that the addition of titanium slag is omitted, includes the following steps:

[0079] Weigh the following raw materials according to the following proportions by weight: 33 parts waste concrete fine powder, 25 parts fly ash, 63 parts blast furnace slag, 18 parts red mud, 20 parts waste iron filings, 4 parts early strength agent (calcium chloride), 3 parts water reducing agent (calcium lignosulfonate), 6 parts expansion agent (calcium sulfoaluminate expansion agent), and 2 parts composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 3:1).

[0080] Add 2 mol / L hydrochloric acid to the scrap iron and aerate. The amount of hydrochloric acid added is twice the mass of the scrap iron, and the aeration flow rate is 1.5 m³ / h. 3The aeration rate is 1 min, and the aeration time is 1 hour to obtain the reaction material. The reaction material is heated and aged at 98℃ for 2.5 hours to obtain filtrate and filter residue. The filter residue, red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture are mixed evenly to obtain a mixture. Then, the filtrate (10% of the total mass of the mixture) and water (38% of the total mass of the mixture) are added and mixed evenly to obtain solid waste-based grouting material for road repair.

[0081] Comparative Example 3

[0082] A method for preparing a solid waste-based grouting material for road repair, similar to Example 1, except that the addition of scrap iron is omitted, includes the following steps:

[0083] Weigh the following raw materials according to the following proportions by weight: 33 parts waste concrete fine powder, 25 parts fly ash, 63 parts blast furnace slag, 18 parts red mud, 26 parts titanium slag, 4 parts early strength agent (calcium chloride), 3 parts water reducing agent (calcium lignosulfonate), 6 parts expansion agent (calcium sulfoaluminate expansion agent), and 2 parts composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 3:1).

[0084] Add 2 mol / L hydrochloric acid to the titanium slag and aerate it. The amount of hydrochloric acid added is twice the mass of the titanium slag, and the aeration flow rate is 1.5 m³ / h. 3 The aeration rate is 1 min, and the aeration time is 1 hour to obtain the reaction material. The reaction material is heated and aged at 98℃ for 2.5 hours to obtain filtrate and filter residue. The filter residue, red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture are mixed evenly to obtain a mixture. Then, the filtrate (10% of the total mass of the mixture) and water (38% of the total mass of the mixture) are added and mixed evenly to obtain solid waste-based grouting material for road repair.

[0085] Comparative Example 4

[0086] A method for preparing a solid waste-based grouting material for road repair, similar to Example 1, except that the addition of waste concrete powder and red mud is omitted, includes the following steps:

[0087] Weigh the following raw materials according to the following weight proportions: 25 parts fly ash, 63 parts blast furnace slag, 20 parts waste iron filings, 26 parts titanium slag, 4 parts early strength agent (calcium chloride), 3 parts water reducing agent (calcium lignosulfonate), 6 parts expansion agent (calcium sulfoaluminate expansion agent), and 2 parts composite admixture (disodium hydrogen phosphate and borax in a weight ratio of 3:1).

[0088] Titanium slag and scrap iron were mixed, then 2 mol / L hydrochloric acid was added and aerated. The amount of hydrochloric acid added was twice the total mass of the titanium slag and scrap iron, and the aeration flow rate was 1.5 m³ / h. 3The aeration rate is 1 min, and the aeration time is 1 hour to obtain the reaction material. The reaction material is heated and aged at 98℃ for 2.5 hours to obtain filtrate and filter residue. The filter residue is mixed evenly with fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite additive to obtain a mixture. Then, filtrate (10% of the total mass of the mixture) and water (38% of the total mass of the mixture) are added and mixed evenly to obtain solid waste-based grouting material for road repair.

[0089] Comparative Example 5

[0090] Same as Example 1, except that the following raw materials are weighed in parts by weight: 10 parts waste concrete fine powder, 50 parts fly ash, 20 parts blast furnace slag, 40 parts red mud, 30 parts waste iron filings, 10 parts titanium slag, 2 parts early strength agent, 5 parts water reducing agent, 3 parts expansion agent and 5 parts composite admixture.

[0091] Performance testing

[0092] The initial setting time, final setting time, compressive strength, flexural strength, corrosion resistance and frost resistance of the solid waste-based grouting materials for road repair prepared in Examples 1-4 and Comparative Examples 1-5 were determined in accordance with JTG / T 50 "Technical Specification for Construction of Highway Bridges and Culverts", SL 352 "Test Procedure for Hydraulic Concrete" and JC / T1011 "Concrete Anti-sulfurization Corrosion Inhibitors". The results are shown in Tables 1 and 2.

[0093] Table 1. Performance test results of grouting materials in Examples 1-4 and Comparative Examples 1-5

[0094] Initial setting time / min Final setting time / min Corrosion resistance coefficient Freeze resistance rating Example 1 176 228 1.02 200 freeze-thaw cycles Example 2 185 232 1.02 198 freeze-thaw cycles Example 3 179 229 1.02 190 freeze-thaw cycles Example 4 183 237 1.01 194 freeze-thaw cycles Comparative Example 1 204 269 0.87 130 freeze-thaw cycles Comparative Example 2 196 254 0.82 148 freeze-thaw cycles Comparative Example 3 194 257 0.95 137 freeze-thaw cycles Comparative Example 4 201 260 0.74 152 freeze-thaw cycles Comparative Example 5 189 251 0.92 176 freeze-thaw cycles

[0095] Table 2. Performance test results of grouting materials in Examples 1-4 and Comparative Examples 1-5

[0096]

[0097] As can be seen from Tables 1 and 2, the grouting material prepared in the embodiments of the present invention has the advantages of short setting time, excellent mechanical properties, corrosion resistance, and freeze resistance.

[0098] Compared with Example 1, Comparative Example 1 omits the steps of mixing and aerating titanium slag and waste iron filings, and heating and aging them. Instead, it directly mixes the raw materials. Since titanium in titanium slag and iron in waste iron filings are not easily dissolved, the specific surface area of ​​the mixture and the calcium-iron layered double hydroxide are reduced. Therefore, the setting time, stability and durability of the grouting material are reduced.

[0099] Compared with Example 1, Comparative Examples 2 to 4 omitted the addition of titanium slag, waste iron filings, waste concrete powder, and red mud, respectively. Comparative Example 5 changed the specific dosage of each raw material. Due to the reduction in the types of solid waste materials or the change in dosage, the hydration reaction process of solid waste materials was weakened under the action of various admixtures, and the amount of hydration products and gel mixture generated was reduced, thereby reducing the setting time, stability, and durability of the grouting material. This shows that by reasonably combining these solid waste materials and admixtures, the present invention can significantly improve the durability, thixotropic properties, and volume stability of solid waste-based grouting materials for road repair, thereby improving the quality and durability of road repair.

[0100] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A solid waste-based grouting material for road repair, characterized in that, The preparation method of the solid waste-based grouting material for road repair includes the following steps: weigh the following raw materials according to the following weight proportions: 33 parts of waste concrete fine powder, 25 parts of fly ash, 63 parts of blast furnace slag, 18 parts of red mud, 20 parts of waste iron filings, 26 parts of titanium slag, 4 parts of early strength agent, 3 parts of water-reducing agent, 6 parts of expansion agent, and 2 parts of composite admixture; the composite admixture is composed of disodium hydrogen phosphate and borax in a weight ratio of 3:1; Titanium slag and scrap iron were mixed, then 2 mol / L hydrochloric acid was added and aerated. The amount of hydrochloric acid added was twice the total mass of the titanium slag and scrap iron, and the aeration flow rate was 1.5 m³ / h. 3 The aeration time is 1 hour, and the reaction material is obtained. The reaction material is heated and aged at 98℃ for 2.5 hours to obtain filtrate and filter residue. The filter residue is mixed evenly with red mud, waste concrete fine powder, fly ash, blast furnace slag, early strength agent, water reducing agent, expansion agent and composite admixture to obtain a mixture. Then, the filtrate and water are added and mixed evenly to obtain solid waste-based grouting material for road repair.

2. The solid waste-based grouting material for road repair according to claim 1, characterized in that, The particle size of the waste concrete powder, fly ash, and blast furnace slag is all less than 0.2 mm; and / or The particle size of the waste iron filings and titanium slag is less than 0.3 mm; and / or The specific surface area of ​​the red mud is 150–250 m². 2 / kg.

3. The solid waste-based grouting material for road repair according to claim 1, characterized in that, The early-strength agent is one or more of calcium chloride, calcium sulfate, sodium aluminate, and sodium nitrite; and / or The water-reducing agent is a lignin sulfonate or a melamine-based water-reducing agent; and / or The expanding agent is alum stone expanding agent or calcium sulfoaluminate expanding agent.

4. The solid waste-based grouting material for road repair according to claim 1, characterized in that, The amount of water added is 40-60% of the total mass of the mixture, and the amount of filtrate added is 5-20% of the total mass of the mixture.

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