Preparation method and use method of anti-abrasion concrete admixture in freeze-thaw-dissolution environment

Abstract

The present invention discloses a kind of preparation method and use method of anti-abrasion concrete admixture under freeze-thaw-solution environment, the admixture includes the components of following parts by weight:50~60 parts of STG powder, 5~8 parts of polyimide fibers, 1~3 parts of hydroxypropyl methyl (HPMC) cellulose, 10~13 parts of polycarboxylate water-reducing agent, 10~15 parts of antifreeze, 10~13 parts of expansion agent, wherein STG powder includes modified silica fume-glass powder, silicon carbide titanium, graphene oxide. Anti-abrasion concrete admixture under freeze-thaw-solution environment of the present invention can effectively suppress the decomposition of calcium hydroxide, and can refine pore structure, make hydraulic concrete more compact, while improving the ability of hydraulic concrete to resist dissolution, enhance its anti-abrasion performance, the admixture has good low temperature resistance, can be applicable to cold low temperature environment, for the anti-abrasion strength under low temperature conditions there is obvious improvement.

Description

Technical Field

[0001] The invention belongs to the technical field of building material concrete admixtures, and in particular relates to a preparation method and a use method of an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment. Background Art

[0002] Hydraulic dam concrete is a typical large-volume concrete with concentrated hydration heat release and rapid internal temperature rise, resulting in a complex engineering environment. In high-altitude areas, winter temperatures generally fluctuate between -50°C and 0°C. Hydraulic structures are subject to freeze-thaw cycles of rising and falling temperatures, and the moisture within the structure undergoes a water-to-ice-to-water phase transition. Repeated freeze-thaw cycles can destabilize the internal structure and easily cause concrete cracking. Hydraulic structures in dam environments are frequently exposed to ambient water, resulting in a concentration difference between the concrete's pore solution and the ambient aqueous solution. This can cause calcium ions to bleed from the concrete into the ambient water, leading to the decomposition of the CSH gel in the concrete structure, a degradation of material properties, and a reduction in the strength of the structure. Furthermore, the flow surfaces of hydraulic structures are frequently eroded by debris, and the impact and abrasion of sand-laden water can degrade the structure, severely impacting the service life of the hydraulic structures.

[0003] At present, there are mainly the following preventive measures to address the anti-erosion problem of hydraulic concrete in different environments: adding mineral admixtures such as fly ash and silica fume to improve the strength of concrete and enhance its resistance to erosion and abrasion, but excessive fly ash and silica fume will reduce the frost resistance of concrete; adding ordinary fibers can improve the crack resistance and wear resistance of concrete, but the effect of fibers is not particularly obvious in low-temperature environments; in addition, most of the existing literature studies the anti-erosion performance of hydraulic concrete under single freeze-thaw conditions and single dissolution conditions, and cannot take into account the anti-erosion performance of concrete in a dissolution-freeze-thaw environment.

[0004] Therefore, it is necessary to study an anti-abrasion concrete admixture under freeze-thaw-dissolution environment to improve the anti-abrasion performance of concrete and solve the durability problem of hydraulic structures under freeze-thaw-dissolution environment. Summary of the Invention

[0005] Purpose of the invention: The purpose of the present invention is to provide an anti-abrasion concrete admixture under a freeze-thaw-dissolution environment, which takes into account the improvement of the anti-abrasion performance of hydraulic concrete under both freeze-thaw and dissolution conditions. By adding the admixture, the decomposition of calcium hydroxide can be reduced, and the anti-dissolution performance of concrete can be improved. The low-temperature resistant polyimide fiber can improve the anti-abrasion performance of concrete in a freeze-thaw environment, and hydroxypropyl methyl (HPMC) cellulose improves the strength and hydrophobicity of hydraulic concrete, further improving the anti-abrasion performance of hydraulic concrete; another purpose of the present invention is to provide a preparation method of the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment; another purpose of the present invention is to provide a method for using the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment.

[0006] Technical solution:

[0007] The present invention discloses an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment. The admixture comprises the following components: by weight, 50 to 60 parts of STG powder, 5 to 8 parts of polyimide fiber, 1 to 3 parts of HPMC cellulose, 10 to 13 parts of polycarboxylic acid water reducer, 10 to 15 parts of antifreeze, and 10 to 13 parts of expansion agent; wherein the STG powder comprises modified silica fume-glass powder, silicon carbide titanium, and graphene oxide.

[0008] Furthermore, the preparation method of modified silica fume-glass powder is: 50 to 55 parts of silica fume and 50 to 55 parts of glass powder are mixed, ball milled and sieving are performed to obtain a mixed powder, the mixed powder is dehydrated, a modifier containing stearic acid is added, and the mixed powder is heated to 120 to 130° C. and continuously dried to obtain modified silica fume-glass powder.

[0009] Furthermore, the silica fume-glass powder is modified by the following method: 50 to 55 parts of silica fume and 50 to 55 parts of glass powder are mixed, the above powders are ball-milled at a speed of 270 r / s for 45 minutes using a ball mill, and sieved through a 0.075 mm sieve to obtain a mixed powder with a particle size of less than or equal to 0.075 mm, the mixed powder is heated to 100 to 110° C. for dehydration, a modifier containing stearic acid is added, it is heated to 120 to 130° C., and it is continuously dried for 2 to 4 hours, and the agglomerated mixture is beaten into powder using a blender, and then sieved through a 0.075 mm sieve to obtain modified silica fume-glass powder.

[0010] Furthermore, the STG powder includes the following components: by weight, 50 to 60 parts of modified silica fume-glass powder, 0.5 to 1 part of graphene oxide powder, and 2 to 2.5 parts of titanium silicon carbide.

[0011] The preparation method of STG powder is as follows: graphene oxide powder, titanium silicon carbide and modified silica fume-glass powder are uniformly stirred in a blender to obtain STG powder.

[0012] Furthermore, the modifier containing stearic acid comprises the following components: by weight, 85 to 95 parts of water, 4 to 6 parts of stearic acid, 1 to 2 parts of sodium hydroxide, 1 to 2 parts of calcium hydroxide, and 1 part of potassium hydroxide.

[0013] Furthermore, the preparation method of the modifier containing stearic acid is: mixing the components and heating them to perform saponification reaction, and obtaining the modifier after 2 to 4 hours.

[0014] Preferably, the loss on ignition of the silica fume is 3.92%, and the specific surface area is 19.1m 2 / g, chloride ion content is 0.07%, and silicon dioxide content is 96.1%.

[0015] Preferably, the glass powder has a softening temperature of ≥360°C and a linear expansion coefficient of 50×10 -7 ~160×10 -7 , particle size 5~10μm.

[0016] Preferably, the graphene oxide is a brown powder with a particle size of 20 to 40 μm and an oxygen content of 40 to 45%.

[0017] Preferably, the titanium silicon carbide is a gray-black powder with a particle size of 5 to 10 μm and a density of 5.87 g / cm 3 .

[0018] Preferably, the polyimide fiber has a diameter of 2 mm and a length of 6 mm.

[0019] Preferably, the HPMC cellulose is a white slightly yellow powder with a fineness of 80-100 mesh and a loss on drying of ≤5%.

[0020] Preferably, the polycarboxylic acid high-performance water-reducing agent has a water reduction rate of 28%, an air content of 3%, and a water bleeding rate of 20%.

[0021] Preferably, the antifreeze has a water bleeding rate of ≤95%, a gas content of ≤4%, and a water reduction rate of 8-12%.

[0022] Preferably, the expansion agent is a TD-P1 concrete expansion agent, with a limited expansion rate of 0.08% to 0.1%, and a potassium oxide and sodium oxide content of 0.3% to 0.4%.

[0023] The anti-abrasion concrete admixture under the freeze-thaw-dissolution environment of the present invention, takes into account the anti-abrasion performance of hydraulic concrete under freeze-thaw and dissolution, can effectively suppress the decomposition of calcium hydroxide, reach the ability of strengthening hydraulic concrete anti-dissolution, and the admixture can refine the pore structure, make hydraulic concrete more compact, thereby improving its anti-abrasion performance; At the same time, the admixture of the present invention can make the connection between mortar and aggregate tighter, improve the bonding ability of concrete internal structure, strengthen the strength of concrete, and can also be used in cold low-temperature environment, for the anti-abrasion strength under low temperature conditions has obvious improvement. In addition, when the STG powder in the admixture of the present invention is used in conjunction with antifreeze and expansion agent, it is ensured that the volume stability of hydraulic structures under freeze-thaw conditions, the impact of calcium ion dissolution on the durability of hydraulic concrete is also reduced, and more importantly, the anti-abrasion performance of hydraulic concrete is improved. Under the joint action of various components, the corrosion depth of the anti-abrasion concrete of the present invention at 7d, 14d and 28d decreased by 28.57%, 26.58% and 21.88% respectively relative to the blank group, the mass loss after 25, 50, 75 and 100 freeze-thaw cycles decreased by 33.33%, 36.36%, 25% and 16% respectively relative to the blank group, and the anti-abrasion strength after 28d of corrosion and 0, 50 and 100 freeze-thaw cycles increased by 22.49%, 29.17% and 39.81% relative to the blank group. The hydraulic concrete using the admixture of the present invention has good freeze-thaw resistance, corrosion resistance and anti-abrasion characteristics.

[0024] On the other hand, the present invention provides a method for preparing an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment. The preparation method comprises: uniformly stirring 50 to 60 parts of STG powder, 5 to 8 parts of polyimide fiber, 1 to 3 parts of HPMC cellulose, 10 to 13 parts of polycarboxylic acid water reducer, 10 to 15 parts of antifreeze, and 10 to 13 parts of expansion agent to obtain an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment.

[0025] Specifically, the components of the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment are placed in a cement mortar mixer and stirred for 4 minutes. After uniform mixing, the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment is obtained. Specifically, 50 to 60 parts by mass of silica fume and 50 to 60 parts of glass powder are mixed, and the above powders are ball-milled at a speed of 270 r / s for 45 minutes using a ball mill, and sieved through a 0.075 mm sieve to obtain a mixed powder with a particle size of less than or equal to 0.075 mm. The mixed powder is heated to 100-110° C. for dehydration, and a modifier containing stearic acid is added. The mixture is heated to 120-130° C. and continuously dried for 2 to 4 hours. The agglomerated mixture is powdered using a mixer and then sieved through a 0.075 mm sieve to obtain modified silica fume-glass powder. 50-60 parts of modified silica fume-glass powder, 0.5-1 part of graphene oxide, and 2-3 parts of titanium silicon carbide were uniformly stirred for 3-4 minutes to obtain STG powder. 50-60 parts of STG powder, 5-8 parts of polyimide fiber, 1-3 parts of HPMC cellulose, 10-13 parts of polycarboxylate water reducer, 10-15 parts of antifreeze, and 10-13 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain an anti-abrasion concrete admixture for freeze-thaw-dissolution environment.

[0026] On the other hand, the present invention provides a method for using the above-mentioned anti-abrasion concrete admixture in a freeze-thaw-dissolution environment. After dry mixing of concrete aggregate, the admixture is wet mixed with water to obtain hydraulic concrete, and the admixture is added in an amount of 4.0 to 6.0 kg per cubic meter of concrete.

[0027] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0028] (1) The present invention takes into account the anti-abrasion performance of hydraulic concrete under freeze-thaw and dissolution, can effectively inhibit the decomposition of calcium hydroxide, thereby enhancing the anti-dissolution ability of hydraulic concrete, and can refine the pore structure, making the hydraulic concrete more dense, thereby improving its anti-abrasion performance;

[0029] (2) The anti-abrasion concrete admixture of the present invention in a freeze-thaw-dissolution environment can make the connection between mortar and aggregate tighter, improve the bonding ability of the internal structure of concrete, enhance the strength of concrete, and can be used in cold and low-temperature environments, and has a significant improvement in anti-abrasion strength under low-temperature conditions;

[0030] (3) The anti-abrasion concrete admixture of the present invention under freeze-thaw-dissolution environment ensures the volume stability of hydraulic structures under freeze-thaw conditions, reduces the effect of calcium ion dissolution on the durability of hydraulic concrete, and more importantly, improves the anti-abrasion performance of hydraulic concrete;

[0031] (4) Under the action of the admixture of the present invention, the dissolution depth of concrete at 7d, 14d and 28d decreased by 28.57%, 26.58% and 21.88% respectively compared with the blank group, and the mass loss after 25, 50, 75 and 100 freeze-thaw cycles decreased by 33.33%, 36.36%, 25% and 16% respectively compared with the blank group. The abrasion resistance after dissolution for 28d and 0, 50 and 100 freeze-thaw cycles increased by 22.49%, 29.17% and 39.81% compared with the blank group. The hydraulic concrete under the action of the admixture of the present invention has good freeze-thaw resistance, dissolution resistance and abrasion resistance. DETAILED DESCRIPTION

[0032] The following is a detailed, clear, and complete description of the technical solutions of the present invention. It should be understood that the examples described are merely a portion of actual examples and do not represent all practical examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without inventive effort are intended to fall within the scope of protection of the present invention.

[0033] The present invention provides an anti-abrasion concrete admixture for freeze-thaw-dissolution environments, comprising the following components by weight: 50-60 parts STG powder, 5-8 parts polyimide fiber, 1-3 parts HPMC cellulose, 10-13 parts polycarboxylate superplasticizer, 10-15 parts antifreeze, and 10-13 parts expansion agent. The STG powder includes modified silica fume-glass powder, titanium silicon carbide, and graphene oxide.

[0034] In the following examples and comparative examples, the loss on ignition of silica fume is 3.92% and the specific surface area is 19.1 m 2 / g, chloride ion content is 0.07%, silicon dioxide content is 96.1%; glass powder softening temperature is ≥360℃, linear expansion coefficient is 50×10 -7 ~160×10 -7 , particle size 5-10μm; graphene oxide is brown powder, particle size 20-40μm, oxygen content 40-45%; silicon carbide titanium is gray-black powder, particle size 5-10μm, density 5.87g / cm 3The diameter of the polyimide fiber is 2 mm and the length is 6 mm; the HPMC cellulose is a white slightly yellow powder with a fineness of 80-100 mesh and a drying loss of ≤5%; the water reducer is a polycarboxylic acid high-performance water reducer produced by Shanxi Feike New Materials Technology Co., Ltd., with a water reduction rate of 28%, an air content of 3%, and a water bleeding rate of 20%; the antifreeze is a concrete antifreeze produced by Mingzhu Waterproof and Anticorrosive Materials Co., Ltd. in Xinmi City, Henan Province, with a water bleeding rate of ≤95%, an air content of ≤4%, and a water reduction rate of 8-12%; the air entraining agent is the FK-AE type air entraining agent produced by Shanxi Feike New Materials Technology Co., Ltd., with a water reduction rate of 7%, an air content of ≤4.5%, and a water bleeding rate of 25%; the expansive agent is the TD-P1 type concrete expansive agent produced by Nanjing Xinjiasheng New Building Materials Co., Ltd., with a limited expansion rate of 0.08%-0.1%, and potassium oxide and sodium oxide contents of 0.3-0.4%.

[0035] Example 1

[0036] This embodiment provides an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment, comprising the following components in parts by weight: 50 parts of STG powder, 5 parts of polyimide fiber, 1 part of HPMC cellulose, 10 parts of expansion agent, 10 parts of polycarboxylate water reducer, and 10 parts of antifreeze.

[0037] In this embodiment, the preparation method of the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment is as follows: 50 parts of STG powder, 5 parts of polyimide fiber, 1 part of HPMC cellulose, 10 parts of antifreeze, 10 parts of polycarboxylate water reducer, and 10 parts of expansion agent are put into a blender and uniformly stirred for 20 minutes to obtain the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment.

[0038] The STG powder comprises the following components, by weight: 55 parts modified silica fume-glass powder, 0.5 parts graphene oxide, and 2 parts titanium silicon carbide. The STG powder is prepared by mixing 50 parts silica fume and 60 parts glass powder. The powder is ball-milled at 270 rpm for 45 minutes, sieved through a 0.075 mm sieve, and obtained a mixed powder with a particle size of 0.075 mm or less. The mixed powder is then heated to 110°C for dehydration. A modifier containing stearic acid is added, and the mixture is heated to 130°C and dried for 3 hours. The agglomerated mixture is then ground into a powder using a blender and sieved through a 0.075 mm sieve to obtain the modified silica fume-glass powder. The modified silica fume-glass powder is then uniformly stirred with graphene oxide and titanium silicon carbide for 3 minutes to obtain the STG powder.

[0039] The modifier containing stearic acid includes the following components: by weight, 85 parts of water, 4 parts of stearic acid, 1 part of sodium hydroxide, 2 parts of calcium hydroxide, and 1 part of potassium hydroxide.

[0040] The preparation method of the modifier containing stearic acid is as follows: stearic acid, sodium hydroxide, calcium hydroxide, potassium hydroxide and water are mixed and heated to 95° C. to carry out saponification reaction, and the modifier is obtained after 3 hours.

[0041] This embodiment provides an anti-abrasion concrete admixture for freeze-thaw-dissolution environments. After dry-mixing the aggregate of ordinary concrete for 3 minutes, the admixture is wet-mixed with water for 3 minutes to produce hydraulic concrete. The admixture dosage is 4.0 kg per cubic meter of concrete. The ordinary concrete comprises the following components: PO 42.5 cement, water, gravel, sand, a polycarboxylate water-reducing agent, and an air-entraining agent.

[0042] Example 2

[0043] In this embodiment, the preparation method of the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment is as follows: 60 parts of STG powder, 8 parts of polyimide fiber, 3 parts of HPMC cellulose, 15 parts of antifreeze, 10 parts of polycarboxylate water reducer, and 13 parts of expansion agent are placed in a blender and uniformly stirred for 20 minutes to obtain the anti-abrasion concrete admixture under a freeze-thaw-dissolution environment.

[0044] The STG powder comprises the following components, by weight: 60 parts modified silica fume-glass powder, 1 part graphene oxide, and 2.5 parts titanium silicon carbide. The STG powder is prepared by mixing 60 parts silica fume and 50 parts glass powder. The powder is ball-milled at 270 rpm for 45 minutes, and sieved through a 0.075 mm sieve to obtain a mixed powder with a particle size of 0.075 mm or less. The mixed powder is then heated to 110°C for dehydration. A modifier containing stearic acid is added, and the mixture is heated to 130°C and dried for 3 hours. The agglomerated mixture is then ground into a powder using a blender and sieved through a 0.075 mm sieve to obtain the modified silica fume-glass powder. The modified silica fume-glass powder is then uniformly stirred with graphene oxide and titanium silicon carbide for 4 minutes to obtain the STG powder.

[0045] The modifier containing stearic acid includes the following components: 95 parts of water, 6 parts of stearic acid, 2 parts of sodium hydroxide, 1 part of calcium hydroxide, and 1 part of potassium hydroxide.

[0046] The preparation method of the modifier containing stearic acid is the same as that in Example 1.

[0047] This embodiment provides an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment. After dry mixing the aggregate of ordinary concrete for 3 minutes, the admixture is wet mixed with water for 3 minutes to obtain hydraulic concrete. The admixture is added in an amount of 6.0 kg per cubic meter of concrete.

[0048] Example 3

[0049] The preparation method of the hydraulic anti-abrasion concrete anti-freeze-melt admixture in this embodiment is as follows: 55 parts of STG powder, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylic acid water reducer, and 12 parts of expansion agent are placed in a blender and uniformly stirred for 20 minutes to obtain the anti-freeze-thaw-melt concrete admixture.

[0050] The STG powder comprises the following components, by weight: 58 parts modified silica fume-glass powder, 0.8 parts graphene oxide, and 2 parts titanium silicon carbide. The STG powder is prepared by mixing 55 parts silica fume and 55 parts glass powder. The powders are ball-milled at 270 rpm for 45 minutes, sieved through a 0.075 mm sieve, and obtained a mixed powder with a particle size of 0.075 mm or less. The mixed powder is then heated to 110°C for dehydration. A modifier containing stearic acid is added, and the mixture is heated to 130°C and dried for 3 hours. The agglomerated mixture is then ground into a powder using a blender and sieved through a 0.075 mm sieve to obtain the modified silica fume-glass powder. The modified silica fume-glass powder is then uniformly stirred with graphene oxide and titanium silicon carbide for 4 minutes to obtain the STG powder.

[0051] The modifier containing stearic acid comprises the following components: 90 parts by weight of water, 5 parts by weight of stearic acid, 1.5 parts by weight of sodium hydroxide, 1.5 parts by weight of calcium hydroxide, and 1 part by weight of potassium hydroxide. The preparation method of the modifier containing stearic acid is the same as that of Example 1.

[0052] This embodiment provides an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment. After dry mixing the aggregate of ordinary concrete for 3 minutes, the admixture is wet mixed with water for 3 minutes to obtain hydraulic concrete. The admixture is added in an amount of 5.0 kg per cubic meter of concrete.

[0053] Example 4

[0054] This embodiment provides an anti-abrasion concrete admixture in a freeze-thaw-dissolution environment. The difference between this embodiment and Example 1 lies in the preparation of STG powder, and the rest is the same as Example 1.

[0055] The STG powder was prepared by mixing 50 parts of silica fume and 60 parts of glass powder, ball milling the powder at 270 rpm for 45 minutes, and sieving it through a 0.075 mm sieve to obtain a mixed powder with a particle size of 0.075 mm or less. The mixed powder was heated to 100°C for dehydration, and a modifier containing stearic acid was added. The mixture was heated to 120°C and dried for 2 hours. The agglomerated mixture was ground into powder using a blender and sieved through a 0.075 mm sieve to obtain the modified silica fume-glass powder. The modified silica fume-glass powder was then uniformly stirred with graphene oxide and titanium silicon carbide for 4 minutes to obtain the STG powder.

[0056] The modifier containing stearic acid includes the following components: by weight, 85 parts of water, 4 parts of stearic acid, 1 part of sodium hydroxide, 2 parts of calcium hydroxide, and 1 part of potassium hydroxide.

[0057] The preparation method of the modifier containing stearic acid is as follows: stearic acid, sodium hydroxide, calcium hydroxide, potassium hydroxide and water are mixed and heated to 95° C. for saponification reaction, and the modifier is obtained after 2 hours.

[0058] In this embodiment, in the preparation of STG powder, after adding a modifier containing stearic acid, heating to 120° C. for 4 hours can also prepare STG powder.

[0059] In this embodiment, in the preparation of the modifier containing stearic acid, the saponification reaction is carried out for 4 hours to obtain the modifier.

[0060] Comparative Example 1

[0061] Comparative Example 1 differs from Example 3 in that STG powder is not used in this comparative example. Specifically, the admixture comprises the following components, by weight: 7 parts polyimide fiber, 2 parts HPMC cellulose, 12 parts antifreeze agent, 10 parts polycarboxylate water reducer, and 12 parts expansion agent.

[0062] 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylate water-reducing agent, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain a freeze-thaw-dissolution-resistant concrete admixture that does not contain STG powder. The admixture dosage is 5.0 kg per cubic meter of concrete. The preparation method of STG powder is the same as that of Example 3.

[0063] Comparative Example 2

[0064] Comparative Example 2 differs from Example 3 in that unmodified silica fume-glass powder is used in this comparative example. Specifically, the admixture comprises the following components, by weight: 55 parts unmodified silica fume-glass powder (STG), 7 parts polyimide fiber, 2 parts HPMC cellulose, 12 parts antifreeze, 10 parts polycarboxylate superplasticizer, and 12 parts expansion agent. The unmodified silica fume-glass powder (STG) comprises 58 parts unmodified silica fume-glass powder, 0.8 parts graphene oxide, and 2 parts titanium silicon carbide.

[0065] Among them, the preparation method of unmodified silica fume-glass powder is: mix 55 parts of silica fume and 55 parts of glass powder, use a ball mill to ball mill the above powder at a speed of 270r / s for 45 minutes, and sieve through a 0.075mm sieve to obtain a mixed powder with a particle size less than or equal to 0.075mm, heat the mixed powder to 110°C for dehydration, heat to 130°C, and continue drying for 3 hours, use a blender to beat the agglomerated mixture into powder, and then pass through a 0.075mm sieve to obtain unmodified silica fume-glass powder.

[0066] 55 parts of unmodified silica fume-glass powder STG powder, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylate water reducer, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain an unmodified silica fume-glass powder freeze-thaw-solution resistant concrete admixture. The amount of the unmodified silica fume-glass powder admixture was 5.0 kg per cubic meter of concrete. The preparation method of the STG powder was the same as that of Example 3.

[0067] Comparative Example 3

[0068] Comparative Example 3 differs from Example 3 in that graphene oxide is not used in this comparative example. Specifically, the admixture comprises the following components, by weight: 55 parts of STG powder undoped with graphene oxide, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze agent, 10 parts of polycarboxylate water-reducing agent, and 12 parts of expansion agent. The STG powder undoped with graphene oxide comprises 58 parts of modified silica fume-glass powder and 2 parts of titanium silicon carbide.

[0069] 55 parts of STG powder without graphene oxide, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylate water reducer, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain a freeze-thaw-dissolution-resistant concrete admixture without graphene oxide. The admixture was 5.0 kg per cubic meter of concrete. The preparation method of STG powder was the same as that in Example 3.

[0070] Comparative Example 4

[0071] Comparative Example 4 differs from Example 3 in that silicon titanium carbide is not used in this comparative example. Specifically, the admixture comprises the following components, by weight: 55 parts of STG powder undoped with silicon titanium carbide, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylate water-reducing agent, and 12 parts of expansion agent. The STG powder undoped with silicon titanium carbide includes 58 parts of modified silica fume-glass powder and 0.8 parts of graphene oxide.

[0072] 55 parts of STG powder without silicon carbide titanium added, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylate water reducer, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain a freeze-thaw-dissolution-resistant concrete admixture without STG powder. The admixture was added in an amount of 5.0 kg per cubic meter of concrete. The preparation method of STG powder was the same as in Example 3.

[0073] Comparative Example 5

[0074] Comparative Example 5 differs from Example 3 in that polyimide fiber is not used in this comparative example. Specifically, the admixture comprises the following components, by weight: 55 parts STG powder, 2 parts HPMC cellulose, 12 parts antifreeze, 10 parts polycarboxylate water-reducing agent, and 12 parts expansion agent.

[0075] 55 parts of STG powder, 2 parts of HPMC cellulose, 12 parts of antifreeze, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain a freeze-thaw-dissolution-resistant concrete admixture that does not contain polyimide fiber. The admixture was added in an amount of 5.0 kg per cubic meter of concrete. The preparation method of STG powder was the same as in Example 3.

[0076] Comparative Example 6

[0077] Comparative Example 6 differs from Example 3 in that HPMC cellulose is not used in this comparative example. Specifically, the admixture comprises the following components, by weight: 55 parts of STG powder, 7 parts of polyimide fiber, 12 parts of antifreeze agent, 10 parts of polycarboxylate water reducer, and 12 parts of expander.

[0078] 55 parts of STG powder, 7 parts of polyimide fiber, 12 parts of antifreeze agent, 10 parts of polycarboxylate water reducer, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain a freeze-thaw-dissolution-resistant concrete admixture that does not contain HPMC cellulose. The admixture was added in an amount of 5.0 kg per cubic meter of concrete. The preparation method of STG powder was the same as in Example 3.

[0079] Comparative Example 7

[0080] Comparative Example 7 differs from Example 3 in that no expansion agent is used in this comparative example. Specifically, the admixture comprises the following components, by weight: 55 parts of STG powder, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 10 parts of polycarboxylate water reducer, and 12 parts of antifreeze.

[0081] 55 parts of STG powder, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, and 12 parts of antifreeze were placed in a blender and uniformly stirred for 20 minutes to obtain a freeze-thaw-dissolution-resistant concrete admixture that does not contain HPMC cellulose. The admixture dosage was 5.0 kg per cubic meter of concrete. The preparation method of STG powder was the same as in Example 3.

[0082] Comparative Example 8

[0083] Comparative Example 8 differs from Example 3 in that 4.0 kg of the admixture is added per cubic meter of concrete. Specifically, the admixture comprises the following components, by weight: 55 parts STG powder, 7 parts polyimide fiber, 2 parts HPMC cellulose, 12 parts antifreeze, 10 parts polycarboxylate water-reducing agent, and 12 parts expansion agent.

[0084] 55 parts of STG powder, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylate water-reducing agent, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain an HPMC-free freeze-thaw-dissolution resistant concrete admixture. The admixture dosage was 4.0 kg per cubic meter of concrete. The preparation method of STG powder was the same as that in Example 3.

[0085] Comparative Example 9

[0086] Comparative Example 9 differs from Example 3 in that 6.0 kg of the admixture is added per cubic meter of concrete. Specifically, the admixture comprises the following components, by weight: 55 parts STG powder, 7 parts polyimide fiber, 2 parts HPMC cellulose, 12 parts antifreeze agent, 10 parts polycarboxylate water reducer, and 12 parts expansion agent.

[0087] 55 parts of STG powder, 7 parts of polyimide fiber, 2 parts of HPMC cellulose, 12 parts of antifreeze, 10 parts of polycarboxylate water-reducing agent, and 12 parts of expansion agent were placed in a blender and uniformly stirred for 20 minutes to obtain an HPMC-free freeze-thaw-dissolution resistant concrete admixture. The admixture was added in an amount of 6.0 kg per cubic meter of concrete. The preparation method of STG powder was the same as in Example 3.

[0088] Concrete without the freeze-thaw-dissolution anti-abrasion concrete admixture was used as a blank control group. The concrete mix ratio is shown in Table 1. The concrete's anti-dissolution and freeze-thaw resistance were tested according to the relevant provisions of GB / T 50082-2009, "Standard for Test Methods for Long-term Properties and Durability of Ordinary Concrete." The concrete's anti-abrasion strength was tested according to the "Underwater Steel Ball Method" in SL352-2006, "Test Procedure for Hydraulic Concrete." The test results are shown in Tables 2-4.

[0089] Table 1 Concrete mix ratio of blank group

[0090]

[0091] Table 2 Test results of corrosion depth of hydraulic concrete

[0092]

[0093]

[0094] Table 3 Test results of weight loss rate of hydraulic concrete under different freeze-thaw cycles

[0095]

[0096] Table 4 Test results of abrasion resistance of hydraulic concrete after 28 days of freeze-thaw-dissolution

[0097]

[0098] The above test results show that compared with the blank group, the addition of the anti-abrasion concrete admixture of the present invention under freeze-thaw-dissolution conditions reduced the dissolution of calcium hydroxide in hydraulic concrete, and the dissolution depth decreased with the increase in the amount of STG powder in the admixture of the present invention. In addition, the admixture of the present invention has excellent barrier properties, which can effectively prevent the invasion of chloride ions and other harmful substances in water, reduce corrosion to the internal structure of hydraulic concrete, and improve the freeze-thaw resistance of hydraulic concrete. Overall, the durability of hydraulic concrete under freeze-thaw and dissolution conditions is enhanced. Among the three embodiments, Example 3 has the best effect. The corrosion depth at 7d, 14d and 28d decreased by 28.57%, 26.58% and 21.88% respectively relative to the blank group. The mass loss after 25, 50, 75 and 100 freeze-thaw cycles decreased by 33.33%, 36.36%, 25% and 16% respectively relative to the blank group. The abrasion resistance after 28d corrosion and 0, 50 and 100 freeze-thaw cycles increased by 22.49%, 29.17% and 39.81% relative to the blank group. Compared with the embodiments, the abrasion resistance, corrosion resistance and freeze-thaw resistance in the comparative example all decreased. Therefore, the addition of the admixture of the present invention can effectively improve the abrasion resistance of hydraulic concrete under freeze-thaw and corrosion conditions and improve the durability of hydraulic structures.

[0099] The above are all preferred embodiments of the present invention, and are not intended to limit the scope of protection of this application. Any modifications, equivalent replacements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A concrete admixture resistant to abrasion in a freeze-thaw-dissolution environment, characterized in that: The admixture comprises the following components in parts by weight: 50-60 parts of STG powder, 5-8 parts of polyimide fiber, 1-3 parts of HPMC cellulose, 10-13 parts of polycarboxylic acid water reducer, 10-15 parts of antifreeze, and 10-13 parts of expansion agent. The STG powder comprises the following components in parts by weight: 55-60 parts of modified silica fume-glass powder, 0.5-1 part of graphene oxide powder, and 2-2.5 parts of titanium silicon carbide. Preparation method of modified silica fume-glass powder The method comprises the following steps: mixing 50-55 parts of silica fume and 50-55 parts of glass powder, ball milling and sieving the mixed powder to obtain a mixed powder; dehydrating the mixed powder; adding a modifier containing stearic acid; heating the mixed powder to 120-130° C.; and continuously drying the mixed powder to obtain modified silica fume-glass powder; wherein the modifier containing stearic acid comprises the following components in parts by weight: 85-95 parts of water, 4-6 parts of stearic acid, 1-2 parts of sodium hydroxide, 1-2 parts of calcium hydroxide, and 1 part of potassium hydroxide.

2. The anti-abrasion concrete admixture under freeze-thaw-corrosion environment according to claim 1, characterized in that The preparation method of STG powder is as follows: graphene oxide powder, titanium silicon carbide and modified silica fume-glass powder are uniformly stirred to obtain STG powder.

3. The anti-abrasion concrete admixture under freeze-thaw-corrosion environment according to claim 1, characterized in that The water seepage rate of antifreeze is ≤95%, the air content is ≤4%, and the water reduction rate is 8~12%.

4. The anti-abrasion concrete admixture under freeze-thaw-corrosion environment according to claim 1, characterized in that The expansion agent is TD-P1 concrete expansion agent, which limits the expansion rate to 0.08%~0.1% and the potassium oxide and sodium oxide content to 0.3~0.4%.

5. The anti-abrasion concrete admixture under freeze-thaw-corrosion environment according to claim 1, characterized in that The preparation method of the modifier containing stearic acid is as follows: stearic acid, sodium hydroxide, calcium hydroxide, potassium hydroxide and water are mixed and heated to carry out a saponification reaction, and the modifier is obtained after 2 to 4 hours.

6. A method for preparing an anti-abrasion concrete admixture under a freeze-thaw-dissolution environment according to any one of claims 1 to 5, characterized in that: Mix 50-60 parts of STG powder, 5-8 parts of polyimide fiber, 1-3 parts of HPMC cellulose, 10-13 parts of polycarboxylic acid water reducer, 10-15 parts of antifreeze, and 10-13 parts of expansion agent to obtain an anti-abrasion concrete admixture under freeze-thaw-dissolution environment.

7. A method for using the anti-abrasion concrete admixture in a freeze-thaw-dissolution environment according to any one of claims 1 to 5, characterized in that: After dry mixing of concrete aggregates, the admixture is wet mixed with water to obtain hydraulic concrete, and the admixture dosage is 4.0-6.0 kg per cubic meter of concrete.

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