Low-carbon road grouting material dry powder composition with self-regulating performance and preparation method thereof

Abstract

The application provides a low-carbon road grouting material dry powder composition with self-regulating performance and a preparation method thereof, which comprises the following components based on 100 parts of total weight: 45-55 parts of slag, 25-30 parts of steel slag, 5-10 parts of fly ash, 1-2 parts of modified bentonite, 10-15 parts of activator, 0.5-1 part of expanding agent, 0.5-1 part of water reducing agent, 0.1-0.2 part of interface agent and 1-2 parts of phase change water retaining agent. The modified bentonite is used to promote the dispersion of the grouting material in water by using the space stereo structure of alkyl chain and hydroxyl isomerization; the phase change water retaining agent is used to regulate the moisture release of the water retaining material by changing the phase change state of paraffin at different environmental temperatures, so as to realize the fine regulation of the moisture content in the grouting material; finally, the polysiloxane powder is used to promote the formation of a good interface between the grouting material and the silicon dioxide at the repair position, so that the self-regulation and stability of the performance of the grouting material according to the environmental conditions are realized.

Description

Technical Field

[0001] This invention relates to the field of road engineering structure void repair technology, specifically to a low-carbon road grouting material dry powder composition with self-regulating performance and its preparation method. Background Technology

[0002] As my country's comprehensive national strength continues to increase, the scale of road construction is also expanding, greatly facilitating people's travel. However, different types of roadbed and pavement defects are becoming increasingly prominent, not only affecting the normal use of roads but also leading to frequent traffic accidents and seriously impacting people's lives and property. Investigations into early-stage defects in cement and asphalt pavements reveal that interlayer voids and poor or weak interlayer bonding are among the key causes of early pavement damage. Therefore, early preventative maintenance of the base, subbase, and surface layers of cement concrete and asphalt concrete pavements—filling interlayer voids, strengthening interlayer bonding, improving the overall load-bearing capacity of the pavement, sealing surface layer cracks, and preventing moisture infiltration into the pavement structure—can significantly reduce later pavement damage and extend road service life.

[0003] Grouting materials are an indispensable and crucial component in road structure reinforcement technology. Existing grouting materials are generally mixtures of two or more of the following: cement grout, polyurethane grout, and polymer-modified asphalt. However, the performance of such grouting materials is greatly affected by ambient temperature and humidity during construction, resulting in unstable performance and weak early compressive strength. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a low-carbon road grouting material dry powder composition with self-regulating performance and its preparation method, which can solve the existing problems.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] This invention is achieved through the following technical solution: a low-carbon road grouting material dry powder composition with self-regulating performance, comprising the following components based on a total weight of 100 parts: 45-55 parts slag, 25-30 parts steel slag, 5-10 parts fly ash, 1-2 parts modified bentonite, 10-15 parts activator, 0.5-1 part expansion agent, 0.5-1 part water-reducing agent, 0.1-0.2 parts interface agent, and 1-2 parts phase change water-retaining agent.

[0007] Furthermore, the specific surface area of ​​the modified bentonite is not less than 300 m². 2 / kg; the modified bentonite is prepared from sodium-based bentonite by modification with triisopropanolamine.

[0008] Furthermore, the modified bentonite is prepared by modifying sodium-based bentonite with triisopropanolamine, comprising:

[0009] The sodium-based bentonite was mixed and stirred with hydrochloric acid solution, and then the suspension was centrifuged after stirring.

[0010] Rinse the bottom precipitate with deionized water and centrifuge until it is neutral. Remove the bottom precipitate and dry it.

[0011] The dried precipitate was ground and sieved to obtain acidified bentonite.

[0012] Triisopropanolamine was added to deionized water and stirred until dissolved. Acidified bentonite was added to the hydrolyzed solution and stirred.

[0013] After stirring, the suspension is centrifuged, and the precipitate is vacuum dried and ground to obtain modified bentonite.

[0014] Furthermore, the preparation method of the phase change water-retaining agent includes:

[0015] Prepare a neutral pH solution of potassium hydroxide and acrylic acid.

[0016] Acrylamide and polysaccharide are added to the mixed solution until completely dissolved;

[0017] After complete dissolution, the temperature is raised to 70°C and the reaction is carried out for at least 2 hours. Then, the mixture is sent to a vacuum drying chamber and vacuum dried at 40°C to form a water-retaining block.

[0018] The dried water-retaining block was broken down to 75μm to obtain water-retaining powder;

[0019] The water-retaining powder was added to the paraffin emulsion and stirred at 500 r / min for 0.5 hours at 70°C. After centrifugation and drying, the powder was ground to 75 μm to obtain the phase change water-retaining agent.

[0020] Furthermore, the polysaccharide includes starch or glucose; the mass of the acrylamide and polysaccharide is based on 100 parts, wherein the acrylamide is 50 parts and the polysaccharide is 50 parts; the mass of the acrylamide and polysaccharide is 40% of the mass of the mixed solution; the water-retaining powder is 40% of the mass of the paraffin emulsion.

[0021] Furthermore, the paraffin emulsion is prepared by stirring paraffin and an aqueous ethanol solution at 85°C for 0.5 hours to form a paraffin emulsion; the mass ratio of paraffin to aqueous ethanol solution is 4:1.

[0022] Furthermore, the interface agent includes polysiloxane powder.

[0023] Furthermore, the interface agent comprises SHP-50 polysiloxane, wherein the particle size of the interface agent is greater than 200 μm and the specific surface area is not less than 500 m². 2 / kg; the activator includes at least one of sodium sulfate, sodium carbonate, sodium metasilicate, and sodium aluminate powder; the water-reducing agent includes one of naphthalene, polycarboxylic acid, and lignin; the expanding agent is a plastic expanding agent.

[0024] Furthermore, the slag has a particle size of less than 250 μm and a specific surface area of ​​not less than 450 m². 2 / kg; the particle size of the fly ash is less than 250μm, and the specific surface area is not less than 400m². 2 / kg; the average particle size of the steel slag is not less than 20 μm, and the specific surface area is not less than 450 m². 2 / kg.

[0025] This invention also provides a method for preparing a low-carbon road grouting material dry powder composition with self-regulating performance. The dry powder composition is prepared by adding the components of the dry powder composition according to the weight ratio of each component described in any one of the above-mentioned methods into a mixing device, with a mixing speed of 50-150 rpm, a temperature of 10-40°C, and a mixing time of 2-4 hours; the dry powder composition can then be obtained.

[0026] Compared with the prior art, the beneficial effects of the present invention include:

[0027] This invention relates to a low-carbon road grouting material dry powder composition with self-regulating performance and its preparation method. It utilizes modified bentonite loaded with triisopropanolamine, leveraging its alkyl chain and hydroxyl isomer spatial stereostructure to promote the dispersion of the grouting material in water. By utilizing the different phase change states of paraffin wax under different environmental temperatures, the water release of the water-retaining material is controlled, achieving micro-control of the moisture content in the grouting material. Finally, polysiloxane powder promotes the formation of a good interface between the grouting material and the silica at the repair site, thus achieving self-regulation and stability of the grouting material's performance according to environmental conditions. This effectively solves the problem that environmental temperature severely affects the setting time and early strength of the grouting material during road grouting, ensuring the stability of the grouting material and its repair effect. Furthermore, this invention uses solid waste materials as the grouting material, resulting in lower costs. Detailed Implementation

[0028] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following specific embodiments are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0029] This invention provides a low-carbon road grouting material dry powder composition with self-regulating performance, comprising the following components based on a total weight of 100 parts: 45-55 parts slag, 25-30 parts steel slag, 5-10 parts fly ash, 1-2 parts modified bentonite, 10-15 parts activator, 0.5-1 part expansion agent, 0.5-1 part water-reducing agent, 0.1-0.2 parts interface agent, and 1-2 parts phase change water-retaining agent.

[0030] The slag, fly ash, and steel slag mentioned may be derived from solid waste.

[0031] The slag has a particle size of less than 250 μm and a specific surface area of ​​not less than 450 m². 2 / kg;

[0032] The fly ash has a particle size of less than 250 μm and a specific surface area of ​​not less than 400 m². 2 / kg;

[0033] The steel slag has an average particle size of not less than 20 μm and a specific surface area of ​​not less than 450 m². 2 / kg.

[0034] The specific surface area of ​​the modified bentonite is not less than 300 m². 2 / kg; the modified bentonite is prepared from sodium-based bentonite through modification with triisopropanolamine, specifically,

[0035] 5g of bentonite was dissolved in 50ml of hydrochloric acid solution (1.5mol / L), and the solution was kept at 20℃ and stirred for 5 hours. After stirring, the suspension was centrifuged, and the bottom precipitate was washed with deionized water 4 to 6 times until the solution was neutral. The bottom precipitate was then removed and placed in a vacuum oven to dry at 60℃ for 90 minutes. Finally, the dried precipitate was ground and passed through a 300-mesh sieve to prepare acidified bentonite for further modification.

[0036] 2.0 g of triisopropanolamine was added dropwise to 50 ml of deionized water and hydrolyzed by stirring at room temperature for 1 hour. Then, 1 g of acidified bentonite was added to the hydrolysis solution, and the mixture was stirred at 90 °C for 2 hours. The suspension was then centrifuged, and the lower precipitate was dried in a vacuum oven at 105 °C for 2 hours. Finally, the dried precipitate was ground and sieved again through a 300-mesh sieve to obtain modified bentonite.

[0037] The preparation method of the phase change water-retaining agent includes: preparing a neutral pH mixed solution of potassium hydroxide and acrylic acid; adding acrylamide and polysaccharide to the mixed solution until completely dissolved; after complete dissolution, heating to 70°C and reacting for at least 2 hours, then sending it to a vacuum drying chamber and vacuum drying at 40°C to form a water-retaining block; crushing the dried water-retaining block to 75 μm to obtain water-retaining powder; adding the water-retaining powder to a paraffin emulsion, stirring at 500 r / min for 0.5 hours at 70°C, centrifuging and drying, and then grinding to 75 μm to obtain the phase change water-retaining agent.

[0038] Specifically, the polysaccharide includes starch or glucose; the mass of the acrylamide and polysaccharide is based on 100 parts, wherein the acrylamide is 50 parts and the polysaccharide is 50 parts; the mass of the acrylamide and polysaccharide is 40% of the mass of the mixed solution; the water-retaining powder is 40% of the mass of the paraffin emulsion.

[0039] Specifically, the paraffin emulsion is prepared by stirring paraffin and an aqueous ethanol solution at 85°C for 0.5 hours to form a paraffin emulsion; the mass ratio of paraffin to aqueous ethanol solution is 4:1.

[0040] The interface agent comprises polysiloxane powder; for example, the interface agent comprises SHP-50 polysiloxane, wherein the particle size of the interface agent is greater than 200 μm and the specific surface area is not less than 500 m². 2 / kg; the activator includes at least one of sodium sulfate, sodium carbonate, sodium metasilicate, and sodium aluminate powder; the water-reducing agent includes one of naphthalene, polycarboxylic acid, and lignin; the expanding agent is a plastic expanding agent.

[0041] This invention also provides a method for preparing a low-carbon road grouting material dry powder composition with self-regulating performance, comprising:

[0042] The following ingredients are prepared based on a total weight of 100 parts: 45-55 parts slag, 25-30 parts steel slag, 5-10 parts fly ash, 1-2 parts modified bentonite, 10-15 parts activator, 0.5-1 part expanding agent, 0.5-1 part water-reducing agent, 0.1-0.2 parts interface agent, and 1-2 parts phase change water-retaining agent. The above-mentioned ingredients are added to a mixing device at a stirring speed of 50-150 rpm, a temperature of 10-40°C, and a stirring time of 2-4 hours to obtain a dry powder composition.

[0043] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are explanations of the present invention and not limitations thereof.

[0044] Example 1:

[0045] The dry powder mixture consists of 55 parts slag, 25 parts steel slag, 5 parts fly ash, 2 parts modified bentonite, 10 parts activator, 1 part expanding agent, 0.9 parts water-reducing agent, 0.1 parts interface agent, and 1 part phase change water-retaining agent. The dry powder mixture is obtained by stirring at 50 rpm and 10℃ for 4 hours.

[0046] When using, mix the dry powder mixture with water, with the water mass being 40% of the dry powder mixture mass. This mixture is the grouting material. Its fluidity is 16s, initial setting time is 65min, final setting time is 112min, and 28-day compressive strength is 36.4MPa.

[0047] Example 2:

[0048] The dry powder mixture consists of 45 parts slag, 26.3 parts steel slag, 10 parts fly ash, 1 part modified bentonite, 15 parts activator, 0.5 parts expansion agent, 1 part water-reducing agent, 0.2 parts interface agent, and 1 part phase change water-retaining agent. The dry powder mixture is obtained by stirring at 100 rpm and 25°C for 3 hours.

[0049] When using, mix the dry powder mixture with water, with the water mass being 42% of the dry powder mixture mass. This mixture is the grouting material. Its fluidity is 15s, initial setting time is 78min, final setting time is 122min, and 28-day compressive strength is 34.4MPa.

[0050] Example 3:

[0051] The dry powder mixture consists of 47 parts slag, 30 parts steel slag, 8 parts fly ash, 1.5 parts modified bentonite, 11 parts activator, 0.8 parts expansion agent, 0.5 parts water-reducing agent, 0.2 parts interface agent, and 1 part phase change water-retaining agent. The dry powder mixture is obtained by stirring at 150 rpm and 40℃ for 2 hours.

[0052] When using, mix the dry powder mixture with water, with the water mass being 38% of the dry powder mixture mass. This mixture is the grouting material, with a flowability of 17s, an initial setting time of 86min, a final setting time of 147min, and a 28-day compressive strength of 32.4MPa.

[0053] As can be seen from the examples, the dry powder composition of the grouting material of the present invention still has good performance under different environments (different temperatures and humidity). Therefore, the grouting material of the present invention has stable performance during construction and strong early compressive strength.

[0054] This invention achieves performance regulation of grouting materials under different environmental conditions by synergistically regulating the properties of grouting materials using polysilane powder, modified bentonite, and phase change water-retaining materials.

[0055] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A low-carbon road grouting material dry powder composition with self-regulating performance, characterized in that: Based on a total weight of 100 parts, the following components are included: 45-55 parts slag, 25-30 parts steel slag, 5-10 parts fly ash, 1-2 parts modified bentonite, 10-15 parts activator, 0.5-1 part expansion agent, 0.5-1 part water-reducing agent, 0.1-0.2 parts interface agent, and 1-2 parts phase change water-retaining agent. The specific surface area of ​​the modified bentonite is not less than 300 m². 2 / kg; The modified bentonite was prepared by modifying sodium-based bentonite with triisopropanolamine. The modified bentonite is prepared by a method of modifying sodium-based bentonite with triisopropanolamine, comprising: The sodium-based bentonite was mixed and stirred with hydrochloric acid solution, and then the suspension was centrifuged after stirring. Rinse the bottom precipitate with deionized water and centrifuge until it is neutral. Remove the bottom precipitate and dry it. The dried precipitate was ground and sieved to obtain acidified bentonite. Triisopropanolamine was added to deionized water and stirred until dissolved. Acidified bentonite was added to the hydrolyzed solution and stirred. After stirring, the suspension is centrifuged, and the precipitate is vacuum dried, ground, and sieved to obtain modified bentonite. The preparation method of the phase change water-retaining agent includes: Prepare a neutral solution of potassium hydroxide and acrylic acid; Acrylamide and polysaccharide are added to the mixed solution until completely dissolved; After complete dissolution, the temperature is raised to 70°C and the reaction is carried out for at least 2 hours. Then, the mixture is sent to a vacuum drying chamber and vacuum dried at 40°C to form a water-retaining block. The dried water-retaining block was broken down to 75μm to obtain water-retaining powder; The water-retaining powder was added to the paraffin emulsion and stirred at 500 r / min for 0.5 hours at 70°C. After centrifugation and drying, it was ground to 75 μm to obtain the phase change water-retaining agent. The polysaccharide includes starch or glucose; the mass of the acrylamide and polysaccharide is based on 100 parts, of which 50 parts are acrylamide and 50 parts are polysaccharide; the mass of the acrylamide and polysaccharide is 40% of the mass of the mixed solution; the water-retaining powder is 40% of the mass of the paraffin emulsion.

2. The low-carbon road grouting material dry powder composition with self-regulating performance according to claim 1, characterized in that: The paraffin emulsion is prepared by stirring paraffin and an aqueous ethanol solution at 85°C for 0.5 hours to form a paraffin emulsion; the mass ratio of paraffin to aqueous ethanol solution is 4:

1.

3. The low-carbon road grouting material dry powder composition with self-regulating performance according to claim 1, characterized in that: The interface agent includes polysiloxane powder.

4. The low-carbon road grouting material dry powder composition with self-regulating performance according to claim 3, characterized in that: The interface agent comprises SHP-50 polysiloxane, wherein the particle size of the interface agent is greater than 200 μm and the specific surface area is not less than 500 m². 2 / kg; the activator includes at least one of sodium sulfate, sodium carbonate, sodium metasilicate, and sodium aluminate powder; the water-reducing agent includes one of naphthalene, polycarboxylic acid, and lignin; the expanding agent is a plastic expanding agent.

5. The low-carbon road grouting material dry powder composition with self-regulating performance according to claim 1, characterized in that: The slag has a particle size of less than 250 μm and a specific surface area of ​​not less than 450 m². 2 / kg; the particle size of the fly ash is less than 250μm, and the specific surface area is not less than 400m². 2 / kg; the average particle size of the steel slag is not less than 20μm, and the specific surface area is not less than 450m². 2 / kg.

6. A method for preparing a low-carbon road grouting material dry powder composition with self-regulating performance, characterized in that: The dry powder composition according to any one of claims 1 to 5 is added to a stirring device in the specified weight ratio, the stirring speed is 50 to 150 rpm, the temperature is 10 to 40°C, and the stirring time is 2 to 4 hours; the dry powder composition can then be obtained.