Granite slag binary composite rubber emulsified asphalt mortar material and preparation method thereof

Abstract

According to the granite slag binary composite rubber emulsified asphalt mortar material and the preparation method thereof, solid waste slag powder and granite powder serve as alkali-activated raw materials, anionic emulsified asphalt is introduced, alkali in the emulsified asphalt replaces part of alkali in an existing cementing material, and environmental protection is facilitated. Meanwhile, hydration in an alkali-activated system can reduce alkalinity of the emulsified asphalt and absorb moisture in the emulsified asphalt, demulsification of the emulsified asphalt is accelerated, strength is enhanced, and the breaking strength of the emulsified asphalt is improved. According to the invention, the breaking strength of the mortar material is improved while the alkali content in the mortar material is reduced, the risk of early cracking when the mortar material is used as a cement-like cementing material is reduced, and the defect of low early strength when the mortar material is used as an emulsified asphalt mortar material is overcome. According to the invention, an environment-friendly treatment mode is provided for the solid waste granite and slag, and meanwhile, a low-carbon environment-friendly building material is provided.

Description

Technical Field

[0001] The invention relates to the technical field of rubber emulsified asphalt bonding preparation in building materials, and in particular to a granite slag binary composite rubber emulsified asphalt mortar material and a preparation method thereof. Background Art

[0002] Granite is an acidic salt rock material with abundant reserves and low cost. A large amount of granite solid waste is easily generated during the ore mining process. These solid wastes require a large amount of space for stacking, and are easy to affect the air quality, causing great environmental problems. They are a solid waste that needs to be solved urgently. Slag is a by-product of the blast furnace ironmaking process. During the ironmaking process, iron oxide is reduced to metallic iron at high temperature, and impurities such as silica and alumina in the iron ore react with lime and other substances to form a molten material with silicate and aluminosilicate as the main components. After quenching, it becomes a loose and porous granular material, which is blast furnace slag, referred to as slag. Steel mills need to clean up slag regularly, and only part of a large amount of slag is used. A large part of it needs to be harmlessly treated and belongs to industrial waste. If these two solid wastes can be utilized, while reducing the processing cost, it can also better protect the environment.

[0003] At present, asphalt road maintenance is mainly preventive maintenance, and the main maintenance material is emulsified asphalt. Emulsified asphalt has the characteristics of being laid at room temperature, which can provide a good construction environment for road builders and can well overcome the influence of construction seasons. Therefore, emulsified asphalt is widely used in road repair and maintenance projects. However, general emulsified asphalt composite materials have the technical problem of insufficient early strength. Generally, emulsified asphalt and cement are combined to form emulsified asphalt to improve early strength. The industry is actively seeking cement substitutes. Alkali-activated materials are a good choice, but a big disadvantage of alkali-activated materials is that they are brittle and lack toughness.

[0004] The patent with publication number CN103232182A discloses a geopolymer / emulsified asphalt composite material and its preparation method. The geopolymer / emulsified asphalt composite material disclosed in the invention is mainly composed of the following components in parts by weight: 75-95 parts of geopolymer slurry and 5-25 parts of emulsified asphalt. The geopolymer is prepared by mixing an alkali-activated active material with modified water glass in a mass ratio of 1:1. The alkali-activated active material is a mixture of one or more selected from metakaolin, slag and fly ash. The emulsified asphalt uses industrial emulsified asphalt with a solid content of 50-70%. The composite material has excellent performance, high strength, good toughness, and a simple and feasible preparation process. However, its metakaolin requires high-temperature calcination, which consumes huge energy and is not conducive to energy saving and carbon reduction, and requires a large proportion of alkali activator, which is not conducive to environmental protection.

[0005] In view of this, it is necessary to design an improved granite slag binary composite rubber emulsified asphalt mortar material and a preparation method thereof to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a granite slag binary composite rubber emulsified asphalt mortar material and a preparation method thereof, aiming to utilize solid waste, save energy and reduce emissions, and be low-carbon and environmentally friendly while preparing a high-performance cementitious material. The preparation method uses solid waste slag powder and granite powder as alkali-activated raw materials, and reduces its alkali content and improves its flexural strength by introducing anionic emulsified asphalt, thereby reducing the risk of early cracking as a cement-like cementitious material and overcoming the disadvantage of low early strength as an emulsified asphalt mortar material. In addition, the present invention utilizes ordinary solid waste granite that has no activity, which is beneficial to solid waste utilization and energy conservation and emission reduction, and helps to provide an environmentally friendly treatment method for solid waste granite and slag while providing a low-carbon and environmentally friendly building material.

[0007] To achieve the above-mentioned purpose of the invention, the present invention provides a method for preparing a granite slag binary composite rubber emulsified asphalt mortar material, comprising the following steps:

[0008] S1, drying granite and slag particles, grinding and sieving to obtain granite powder and slag powder; the diameter of the granite powder and slag powder is less than 0.075 mm;

[0009] S2, preparation of rubber emulsified asphalt:

[0010] S21, heating the base asphalt to a free-flowing state for standby use; the base asphalt is 70# or 90# base asphalt;

[0011] S22, preparing an emulsion: pouring an anionic emulsifier into warm water at a temperature of 55-65° C. to obtain an emulsion for later use;

[0012] S23, pour hot water into the emulsified asphalt colloid mill to preheat the inside of the emulsified asphalt colloid mill, and then release the hot water; then, slowly pour the base asphalt heated in step S21 and the emulsion prepared in step S22 into the emulsified asphalt colloid mill, stirring while pouring; emulsify for 2-5 minutes after completely pouring; then, pour SBR rubber latex, continue emulsifying for 3-10 minutes and release; after standing in an oven at 55-65°C for 30-60 minutes, take out, and cool naturally to obtain rubber emulsified asphalt; wherein, by mass ratio, the base asphalt: emulsion: SBR latex is (50-60): (40-50): (1-5);

[0013] S3, mixing the granite powder, slag powder and sodium hydroxide particles obtained in step S1 and stirring them evenly to obtain a premixed dry material; wherein, by mass ratio, the ratio of granite to slag is 1:1, and the ratio of granite to sodium hydroxide is (30-10):1;

[0014] S4, mixing water, water glass and the rubber emulsified asphalt obtained in step S23 to obtain an exciting solution;

[0015] S5, mixing the premixed dry materials obtained in step S3 and the stimulating liquid obtained in step S4 and pouring them into a stirring pot, premixing them at 60-140 rpm for 2-5 minutes to allow the stimulating liquid to evenly wet the surface of the dry materials, and then stirring them at 200-300 rpm for 3-6 minutes to make the mixture evenly mixed, and then pouring or pressing them into a mold, curing, and demolding to obtain the granite slag binary composite rubber emulsified asphalt mortar material.

[0016] As a further improvement of the present invention, in step S4, the ratio of water: water glass: rubber emulsified asphalt is (3-5): (2-3): (1-5) by mass.

[0017] As a further improvement of the present invention, the water glass modulus is 1-2.

[0018] As a further improvement of the present invention, the anionic emulsifier is one of fatty acid soap, alkyl sulfate and alkyl benzene sulfonate.

[0019] As a further improvement of the present invention, the anionic emulsifier is sodium dodecylbenzene sulfonate or sodium dodecyl sulfate.

[0020] As a further improvement of the present invention, in step S23, the pH value of the rubber emulsified asphalt is 11-13.

[0021] As a further improvement of the present invention, in step S22, the mass ratio of the anionic emulsifier to water in the emulsion is anionic emulsifier: water = (3-10): (87-96).

[0022] As a further improvement of the present invention, step S22 also includes the following steps: adding an organic stabilizer and an inorganic stabilizer to the emulsion; the organic stabilizer is polyvinyl alcohol PVA, and the inorganic stabilizer is anhydrous sodium sulfate Na2SO4.

[0023] As a further improvement of the present invention, in step S5, the liquid-to-solid ratio is (3-5):(10-12).

[0024] The present invention also provides a granite-slag binary composite rubber emulsified asphalt mortar material, which is prepared by the above-mentioned technical scheme; the granite-slag binary composite rubber emulsified asphalt mortar material is composed of the following components in parts by mass: 35-45 parts of granite, 35-45 parts of slag, 7-10 parts of water glass, 1-3 parts of sodium hydroxide, 6-15 parts of rubber emulsified asphalt, and the balance is water; the rubber emulsified asphalt is prepared by mixing base asphalt, anionic emulsifier emulsion, and SBR latex; wherein, by mass ratio, base asphalt: anionic emulsifier emulsion: SBR latex is (50-60): (40-50): (1-5).

[0025] The beneficial effects of the present invention are:

[0026] 1. The present invention provides a method for preparing a granite slag binary composite rubber emulsified asphalt mortar material, which utilizes two solid waste materials, slag powder and granite powder, as alkali-activated raw materials, and introduces anionic emulsified asphalt to combine with the alkali-activated system, thereby solving the problem of early cracking in alkali-activated cement systems and improving their flexural strength. It also provides a solution to the low early strength of the modified emulsified asphalt system.

[0027] 2. In the present invention, both the alkali-activated cement system and the anionic rubber emulsified asphalt belong to an alkaline system. The addition of anionic rubber emulsified asphalt to the alkali-activated cement system can replace part of the alkali in the emulsified asphalt, thereby playing a role in green environmental protection. At the same time, hydration in the alkali-activated system can reduce the alkalinity of the emulsified asphalt and absorb the moisture in the emulsified asphalt, accelerate the demulsification of the emulsified asphalt, enhance the strength, and improve its flexural strength. Combining rubber emulsified asphalt with alkali-activated materials can not only improve the shortcomings of insufficient toughness and high brittleness of alkali-activated materials, but also can effectively solve the problem of insufficient early compressive strength of general emulsified asphalt composite materials by virtue of the high strength and early strength characteristics of alkali-activated materials.

[0028] 3. The present invention reduces environmental pressure and provides a low-carbon and environmentally friendly cementitious material. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below in conjunction with specific embodiments.

[0030] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0031] The present invention provides a method for preparing a granite slag binary composite rubber emulsified asphalt mortar material, comprising the following steps:

[0032] S1, drying and grinding the granite and slag particles of uneven coarseness and size to obtain granite powder and slag powder; wherein the diameter of the granite powder and the slag powder is less than 0.075 mm;

[0033] S2, preparation of rubber emulsified asphalt:

[0034] S21, heating the base asphalt to a free-flowing state for standby use; wherein the base asphalt is 70# or 90# base asphalt;

[0035] S22, preparing an emulsion: pouring an anionic emulsifier into warm water at a temperature of 55-65° C. to obtain an emulsion for later use;

[0036] The mass ratio of anionic emulsifier to water in the emulsion is anionic emulsifier: water = (3-10): (87-96).

[0037] The anionic emulsifier is one of fatty acid soap, alkyl sulfate and alkyl benzene sulfonate.

[0038] Furthermore, the anionic emulsifier is sodium dodecylbenzene sulfonate or sodium dodecyl sulfate.

[0039] Preferably, step S22 further includes the following steps: adding an organic stabilizer and an inorganic stabilizer to the emulsion. The organic stabilizer is polyvinyl alcohol (PVA), and the inorganic stabilizer is anhydrous sodium sulfate (Na2SO4). In this way, the prepared emulsion can be stored stably for a long time, and is not easy to stratify and demulsify at room temperature.

[0040] S23, pour hot water into the emulsified asphalt colloid mill to preheat the inside of the emulsified asphalt colloid mill, and then release the hot water; then, slowly pour the base asphalt heated in step S21 and the emulsion prepared in step S22 into the emulsified asphalt colloid mill, stirring while pouring; emulsify for 2-5 minutes after completely pouring; then, pour in SBR rubber latex, continue emulsifying for 3-10 minutes and release; after standing in an oven at 55-65℃ for 30-60min, take out, and cool naturally to obtain rubber emulsified asphalt; wherein the pH value of the rubber emulsified asphalt is 11-13.

[0041] Wherein, by mass ratio, the matrix asphalt: emulsion: SBR latex is (50-60): (40-50): (1-5).

[0042] S3, mixing the granite powder, slag powder and sodium hydroxide particles obtained in step S1 and stirring them evenly to obtain a premixed dry material; wherein, by mass ratio, the ratio of granite to slag is 1:1, and the ratio of granite to sodium hydroxide is (30-10):1;

[0043] S4, mixing water, water glass and rubber emulsified asphalt obtained in step S23 to obtain an exciting solution; in step S4, the mass ratio of water: water glass: rubber emulsified asphalt is (3-5): (2-3): (1-5). The modulus of water glass is 1-2.

[0044] S5, mixing the premixed dry materials obtained in step S3 and the stimulating liquid obtained in step S4 and pouring them into a stirring pot, premixing them at 60-140 rpm for 2-5 minutes to allow the stimulating liquid to evenly wet the surface of the dry materials, and then stirring them at 200-300 rpm for 3-6 minutes to make the mixture evenly mixed, and then pouring or pressing them into a mold, curing, and demolding to obtain the granite slag binary composite rubber emulsified asphalt mortar material.

[0045] Among them, the liquid-to-solid ratio of the mixture is (3-5):(10-12).

[0046] The present invention also provides a granite slag binary composite rubber emulsified asphalt mortar material, which is prepared by the above-mentioned preparation method. The granite slag binary composite rubber emulsified asphalt mortar material is composed of the following components in parts by mass: 35-45 parts of granite, 35-45 parts of slag, 7-10 parts of water glass, 1-3 parts of sodium hydroxide, 6-15 parts of rubber emulsified asphalt, and the balance is water. The rubber emulsified asphalt is prepared by mixing base asphalt, anionic emulsifier emulsion, and SBR latex; wherein, by mass ratio, base asphalt: anionic emulsifier emulsion: SBR latex is (50-60): (40-50): (1-5).

[0047] The preparation method of the granite slag binary composite rubber emulsified asphalt mortar material provided by the present invention is described below in conjunction with specific examples. Unless otherwise specified, the raw materials and reagents in the examples of the present application are purchased through commercial channels.

[0048] Example 1

[0049] This embodiment provides a method for preparing a granite slag binary composite rubber emulsified asphalt mortar material, comprising the following steps:

[0050] S1, drying and grinding the granite and slag particles of uneven coarseness and size to obtain ultra-fine granite and slag powder. The sieve size is 200 mesh, and the powder diameter is less than 0.075mm;

[0051] S21, heat 600g of 70# base asphalt to 155°C to make it flow freely and keep it in an oven for later use.

[0052] S22, prepare emulsion: pour 30g of anionic emulsifier (sodium dodecylbenzene sulfonate) into a beaker, then add 6g of organic stabilizer (polyvinyl alcohol PVA) and 6g of inorganic stabilizer (anhydrous sodium sulfate Na2SO4), and finally add 60°C deionized water.

[0053] S23, emulsified asphalt preparation: first open the emulsified asphalt colloid mill, pour in hot water, start it, preheat the entire colloid mill, and then release the hot water. Slowly pour the heated base asphalt and emulsion into the emulsified asphalt colloid mill, stirring while pouring. After pouring completely, emulsify for 3 minutes.

[0054] Then, pour in 50 g of SBR rubber latex and continue emulsifying for 5 minutes, then take it out after standing in a 60° C. oven for 30 minutes and cool it naturally to obtain rubber emulsified asphalt.

[0055] S3, premixed dry materials: weigh 500 g of dried, ground and sieved slag powder and granite powder, respectively, and mix with 30 g of sodium hydroxide particles and stir evenly to obtain premixed dry materials.

[0056] S4, mixing the stimulating liquid: weigh 200g of water, 100g of water glass and 100g of rubber emulsified asphalt and mix them to obtain the stimulating liquid.

[0057] S5, mixing: Mix the premixed dry materials and the stimulating liquid and pour them into the mixing pot. Premix at low speed (70 rpm) for two minutes to allow the stimulating liquid to evenly wet the surface of the dry materials, and then stir at high speed (250 rpm) for 3 minutes to make the mixture evenly mixed and have good fluidity. Subsequently, the granite slag binary composite rubber emulsified asphalt mortar with excellent fluidity is loaded into the mold, vibrated and compacted, and wrapped with plastic wrap for constant temperature maintenance at 25°C. After demolding, the granite slag binary composite rubber emulsified asphalt mortar material is obtained.

[0058] Examples 2-4 and Comparative Example 1

[0059] Compared with Example 1, the difference between Examples 2-4 and Comparative Example 1 is that the formula content is changed. Please see the table below for the specific formula; the rest is roughly the same as Example 1 and will not be repeated here.

[0060] Comparative Example 2

[0061] The difference between Comparative Example 2 and Example 1 is that no rubber emulsified asphalt is added, that is, step S2 is not performed; the rest is roughly the same as Example 1 and will not be repeated here.

[0062] Comparative Example 3

[0063] The difference between Comparative Example 3 and Example 3 is that no SBR rubber latex is added, specifically, no SBR rubber latex is added in step S23; the rest is roughly the same as Example 3, which will not be repeated here.

[0064] Comparative Example 4

[0065] The difference between Comparative Example 4 and Example 3 is that in step S22, the cationic emulsifier hexadecyltrimethylammonium bromide is used to replace the anionic emulsifier sodium dodecylbenzenesulfonate; the rest is roughly the same as Example 3 and will not be repeated here.

[0066] Comparative Example 5

[0067] Compared with Example 3, Comparative Example 5 is different in that, in step S22, the cationic emulsifier hexadecyltrimethylammonium bromide is used to replace the anionic emulsifier sodium dodecylbenzenesulfonate, and SBR rubber latex is not added in step S23; the rest is roughly the same as Example 3 and will not be repeated here.

[0068] Each sample was tested in 3 groups in parallel.

[0069] The compressive strength and flexural strength tests were performed on the samples of Examples 1-4 and Comparative Examples 1-5. The test results are shown in the table below.

[0070] Test method:

[0071] The mortar material was removed from the mold after curing for 1 day, and its 3-day compressive and flexural strength was tested after curing for another 2 days. Compressive strength test: The universal press MTS was used to test the compressive strength (uniaxial compression method) of the sample. The loading method was displacement loading, and the loading rate was 2 mm / min.

[0072] The flexural strength test is as follows: the flexural strength (three-point bending method) of the sample is tested using a universal press MTS. The loading method is displacement loading, and the loading rate is 2 mm / min.

[0073] The dialysis phenomenon and gel condition of the product obtained in step S2 were statistically analyzed, and the results are shown in the table below.

[0074]

[0075]

[0076] It can be seen from the above table that the granite slag binary composite rubber emulsified asphalt mortar prepared in Examples 1-4 has excellent compression and flexural properties and is a green and environmentally friendly building material.

[0077] By comparing Example 1 with Comparative Example 2, it can be seen that adding anionic rubber emulsified asphalt into the alkali activation system can improve its flexural strength.

[0078] By comparing Examples 1-4 with Comparative Examples 1, 4, and 5, it can be seen that the alkali in the anionic rubber emulsified asphalt can replace part of the alkali in the alkali-activated system. However, as can be seen from Comparative Example 1, too low an alkali content will bring negative effects. As can be seen from Example 3 and Comparative Examples 4 and 5, adding anionic rubber emulsified asphalt to the alkali-activated system can improve its flexural strength, which is mainly due to the synergistic effect of the emulsified asphalt and the alkaline environment.

[0079] By comparing Example 3 with Comparative Example 3, it can be seen that the addition of rubber latex can enhance the compression and flexural properties of the granite slag binary composite rubber emulsified asphalt mortar.

[0080] In summary, the appropriate amount of anionic rubber emulsified asphalt added can further improve the flexural strength of the sample while ensuring that the granite slag binary composite rubber emulsified asphalt mortar has better compressive strength.

[0081] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for preparing a granite slag binary composite rubber emulsified asphalt mortar material, characterized in that: The following steps are involved: S1, drying granite and slag particles, grinding and sieving to obtain granite powder and slag powder; the diameter of the granite powder and slag powder is less than 0.075 mm; S2, preparation of rubber emulsified asphalt: S21, heating the base asphalt to a free-flowing state for standby use; the base asphalt is 70# or 90# base asphalt; S22, preparing an emulsion: pouring an anionic emulsifier into warm water at a temperature of 55-65° C. to obtain an emulsion for later use; S23, pour hot water into the emulsified asphalt colloid mill to preheat the inside of the emulsified asphalt colloid mill, and then release the hot water; then, slowly pour the base asphalt heated in step S21 and the emulsion prepared in step S22 into the emulsified asphalt colloid mill, stirring while pouring; emulsify for 2-5 minutes after completely pouring; then, pour SBR rubber latex, continue emulsifying for 3-10 minutes and release; after standing in an oven at 55-65°C for 30-60 minutes, take out, and cool naturally to obtain rubber emulsified asphalt; wherein, by mass ratio, the base asphalt: emulsion: SBR latex is (50-60): (40-50): (1-5); S3, mixing the granite powder, slag powder and sodium hydroxide particles obtained in step S1 and stirring them evenly to obtain a premixed dry material; wherein, by mass ratio, the ratio of granite to slag is 1:1, and the ratio of granite to sodium hydroxide is (30-10):1; S4, mixing water, water glass and the rubber emulsified asphalt obtained in step S23 to obtain an exciting solution; S5, mixing the premixed dry materials obtained in step S3 and the stimulating liquid obtained in step S4 and pouring them into a stirring pot, premixing them at 60-140 rpm for 2-5 minutes to allow the stimulating liquid to evenly wet the surface of the dry materials, and then stirring them at 200-300 rpm for 3-6 minutes to make the mixture evenly mixed, and then pouring or pressing them into a mold, curing, and demolding to obtain the granite slag binary composite rubber emulsified asphalt mortar material.

2. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 1, characterized in that: In step S4, the mass ratio of water: water glass: rubber emulsified asphalt is (3-5): (2-3): (1-5).

3. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 2, characterized in that: The water glass modulus is 1-2.

4. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 1, characterized in that: The anionic emulsifier is one of fatty acid soap, alkyl sulfate and alkyl benzene sulfonate.

5. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 4, characterized in that: The anionic emulsifier is sodium dodecylbenzene sulfonate or sodium dodecyl sulfate.

6. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 1, characterized in that: In step S23, the pH value of the rubber emulsified asphalt is 11-13.

7. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 1, characterized in that: In step S22, the mass ratio of the anionic emulsifier to water in the emulsion is anionic emulsifier: water = (3-10): (87-96).

8. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 1, characterized in that: Step S22 also includes the following steps: adding an organic stabilizer and an inorganic stabilizer to the emulsion; the organic stabilizer is polyvinyl alcohol (PVA), and the inorganic stabilizer is anhydrous sodium sulfate (Na2SO4).

9. The method for preparing the granite slag binary composite rubber emulsified asphalt mortar material according to claim 1, characterized in that: In step S5, the liquid-to-solid ratio is (3-5):(10-12).

10. A granite slag binary composite rubber emulsified asphalt mortar material, characterized in that: It is prepared according to the preparation method described in any one of claims 1 to 9; the granite slag binary composite rubber emulsified asphalt mortar material is composed of the following components in parts by mass: 35-45 parts of granite, 35-45 parts of slag, 7-10 parts of water glass, 1-3 parts of sodium hydroxide, 6-15 parts of rubber emulsified asphalt, and the balance is water; the rubber emulsified asphalt is prepared by mixing base asphalt, anionic emulsifier emulsion, and SBR latex; wherein, by mass ratio, the base asphalt: anionic emulsifier emulsion: SBR latex is (50-60): (40-50): (1-5).

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