Continuous gradation concrete reinforcing and viscosity densifying agent and application thereof

Abstract

The application provides a continuous gradation concrete reinforcing, viscosity increasing and compacting agent and application, which is prepared by compounding micron-sized titanium-containing slag powder and modified silicon micro powder to form continuously graded superfine powder, and is mixed into concrete to be uniformly mixed. The superfine inert material is used to improve the full particle size gradation of concrete, increase the compactness of concrete, and make the cement hydration reaction more sufficient by playing a crystal nucleus role. The superfine modified silicon micro powder can adjust the early strength of concrete. The continuous gradation concrete reinforcing, viscosity increasing and compacting agent prepared according to corresponding components and proportions can be mixed into concrete at a certain proportion to play the roles of reinforcement, early strength, viscosity increase and compactness, and can be used to prepare low-rebound-spraying concrete, high-impact-resistance hydraulic concrete, high-impervious concrete, high-compactness radiation-proof concrete, high-strength high-viscosity anchoring mortar and other high-performance concrete.

Description

Technical Field

[0001] This invention relates to the field of admixtures for concrete and mortar, specifically to a continuously graded concrete reinforcing, thickening, and densifying agent and its application. Background Technology

[0002] Hydraulic concrete and tunnel lining concrete in other industries are mostly subjected to high seepage pressure year-round, making water seepage a common problem. Water seepage causes calcium hydroxide to precipitate from the concrete, reducing its performance. When the water contains harmful substances such as sulfate and chloride ions, it can also corrode the reinforcing steel, significantly shortening the structure's lifespan. Traditionally, concrete strength is considered to come from cement hydration and the skeletal effect of aggregates. When high-quality aggregates are difficult to obtain in engineering projects, the amount of cement is often increased to improve concrete strength. However, this method inevitably leads to increased heat of hydration, increasing the risk of cracking.

[0003] The high rebound rate of shotcrete in tunnel engineering has always been a prominent issue. The rebound rate of shotcrete generally reaches over 20%, and in some cases even 40% to 50%. The material waste caused by high rebound has always been a major problem plaguing construction companies.

[0004] Tunnel projects with poor geological conditions have extremely high requirements for the early-age strength of shotcrete, some even requiring a strength of 8-10 MPa after 6 or 8 hours. How to ensure the workability of concrete while improving its hourly compressive strength is still in the exploratory stage.

[0005] Based on this, the invention of this application is proposed. Summary of the Invention

[0006] The main objective of this invention is to provide a continuously graded concrete reinforcing, thickening, and densifying agent to overcome the shortcomings of existing technologies.

[0007] To address the above problems, the present invention provides the following technical solution:

[0008] One of the objectives of this invention is to provide a continuously graded concrete reinforcing, thickening, and densifying agent, comprising the following components by weight: 37-65 parts titanium-containing slag powder, 34-45 parts modified silica fume, 0.5-1.0 parts water-retaining agent, and 0-20 parts accelerator and early-strength agent.

[0009] In one embodiment of the present invention, the particle size of the titanium-containing slag powder is between 1 μm and 40 μm, and the gradation is continuous.

[0010] In one embodiment of the present invention, the modified silicon micropowder has a particle size between 0.2 μm and 2 μm and a continuous gradation.

[0011] In one embodiment of the present invention, the particle size of the accelerator is between 0.05 μm and 0.4 μm, and the particle size distribution is continuous.

[0012] In one embodiment of the present invention, the particle size of the reinforcing, thickening, and densifying agent is between 0.05 μm and 40 μm, the median diameter is approximately 3-7 μm, and its upper limit of particle size distribution is [missing information]. The lower limit of the gradation is y(x) is the cumulative throughput for particle size x; x is the current particle size in μm.

[0013] In one embodiment of the present invention, the water-retaining agent is a core-shell type nanocomposite water-retaining agent with nano-CaCO3 core, the coagulation and early strength accelerator is a nucleation type early strength accelerator mainly composed of nano-aluminosilicate, the modified silica powder is silica powder mechanically dry modified with titanium ester as powder surface modifier, and the titanium-containing slag powder is high-titanium slag powder produced in Panzhihua area of ​​Sichuan Province after high-temperature conditioning and ultrafine grinding.

[0014] The second objective of this invention is to provide the application of the above-mentioned continuously graded concrete reinforcing, thickening and densifying agent in concrete.

[0015] In one embodiment of the present invention, the dosage is calculated according to the proportion of cement in concrete, and is 5%-30%.

[0016] The beneficial effects of this invention are:

[0017] This invention proposes a continuously graded concrete reinforcing and densifying agent in which coarse and fine particles uniformly fill the voids in the cement and the concrete itself, improving the density of the concrete and enhancing its compressive strength through physical means while avoiding excessive heat of hydration. Titanium-containing slag powder and modified silica fume adjust the micro-gradation of the cementitious material and partially activate the pozzolanic material. The water-retaining agent, nano-CaCO3, has a finer particle size and larger specific surface area. Its crystal structure and surface electronic structure induce quantum size effects, small-size effects, surface effects, and macroscopic quantum effects. Simultaneously, as an inert material, it fills the voids in the cementitious composite material, providing thickening and strengthening effects. The accelerator, nano-aluminosilicate, utilizes the nucleation effect to provide nucleation sites, lower the nucleation barrier, induce C3S and C2S hydration, and improve the early-age strength of the concrete. Detailed Implementation

[0018] To further illustrate the present invention, the following description, in conjunction with embodiments, is provided. It should be understood that these embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. They are merely for further illustrating the features and advantages of the present invention and are not intended to limit the scope of the claims. The protection scope of the present invention should include all the contents of the claims and is not limited to the following embodiments.

[0019] Main raw material types and manufacturers:

[0020]

[0021] Example 1

[0022] Take 37.6 kg of titanium-containing slag powder, 42.4 kg of modified silica powder, 0.8 kg of nano-CaCO3, and 19.2 kg of nano-aluminosilicate. Mix the above materials evenly and seal to obtain a reinforcing, thickening, and densifying agent.

[0023] In this embodiment, the titanium-containing slag powder has a particle size between 1μm and 20μm and a continuous gradation; the modified silica powder has a particle size between 0.2μm and 2μm and a continuous gradation; and the accelerator has a particle size between 0.05μm and 0.4μm and a continuous gradation.

[0024] The particle size of the strengthening, thickening, and densifying agent is between 0.05μm and 20μm, with a median diameter of around 3μm, and its upper limit for particle size distribution is [missing information]. The lower limit of the gradation is y(x) is the cumulative throughput for particle size x; x is the current particle size in μm.

[0025] Example 2

[0026] Take 65 kg of titanium-containing slag powder, 34.2 kg of modified silica powder, and 0.8 kg of nano-CaCO3. Mix the above materials evenly and then seal to obtain a reinforcing, thickening, and densifying agent.

[0027] In this embodiment, the titanium-containing slag powder has a particle size between 1 μm and 40 μm and a continuous gradation. The modified silica powder has a particle size between 0.2 μm and 2 μm and a continuous gradation.

[0028] The particle size of the strengthening, thickening, and densifying agent is between 0.2μm and 40μm, with a median diameter of approximately 7μm, and its upper limit for particle size distribution is [missing information]. The lower limit of the gradation is y(x) is the cumulative throughput for particle size x; x is the current particle size in μm.

[0029] Example 3

[0030] Take 54.2 kg of titanium-containing slag powder, 45 kg of modified silica powder, and 0.8 kg of nano-CaCO3. Mix the above materials evenly and then seal to obtain a reinforcing, thickening, and densifying agent.

[0031] In this embodiment, the titanium-containing slag powder has a particle size between 1 μm and 30 μm and a continuous gradation. The modified silica powder has a particle size between 0.2 μm and 2 μm and a continuous gradation.

[0032] The particle size of the strengthening, thickening, and densifying agent is between 0.2μm and 30μm, with a median diameter of around 5μm, and its upper limit for particle size distribution is [missing information]. The lower limit of the gradation is y(x) is the cumulative throughput for particle size x; x is the current particle size in μm.

[0033] Application examples

[0034] Comparative Example 1: The performance of shotcrete without the addition of this product is compared with that of shotcrete with the addition of the product of this invention.

[0035] Its mix proportion is: 500 kg / m³ of 42.5 cement. 3 Sand 817kg / m 3 817 kg / m³ of crushed stone 3 Water-reducing agent 5.0 kg / m³ 3 40 kg / m³ of quick-setting agent 3 170kg / m³ of water 3 .

[0036] The continuously graded concrete reinforcing, thickening and densifying agent prepared in Example 1 of this invention was added to the concrete and mixed at a dosage of 8% of the cement weight, replacing 8% of the cement by the same mass. The performance comparison of the concrete prepared with that prepared in Comparative Example 1 is shown in Table 1.

[0037] Table 1:

[0038]

[0039] Comparative Example 2: Ordinary concrete without the addition of this product, and its performance is compared with that of ordinary concrete with the addition of the product of this invention.

[0040] Its mix proportion is: 352 kg / m³ of 42.5 cement. 3 Class F, Grade I fly ash: 118 kg / m³ 3 729 kg / m³ of sand 3 1090 kg / m³ of crushed stone 3 Water-reducing agent 4.7 kg / m³ 3 Water 160kg / m 3 .

[0041] The continuous graded concrete reinforcing, thickening and densifying agent prepared in Example 2 of this invention was mixed into concrete at a dosage of 23.5 kg, replacing 23.5 kg of fly ash by the same mass. The performance comparison of the concrete prepared with that prepared in Example 2 is shown in Table 2.

[0042] Table 2:

[0043]

[0044] Comparative Example 3: UHPC concrete without the addition of this product, its performance is compared with that of UHPC concrete with the addition of the product of this invention.

[0045] Its mix proportion is: 820.25 kg / m³ of 42.5 cement. 3 Silica fume 144.75 kg / m³ 3 Quartz sand, 10-40 mesh, 789 kg / m³ 3 Quartz sand, 40-80 mesh, 3327 kg / m³ 3 , quartz sand 80-120 mesh 119kg / m 3 , quartz sand 120-180 mesh 68kg / m 3 Water-reducing agent 24.2 kg / m³ 3 Water 347kg / m 3 .

[0046] The continuously graded concrete reinforcing, thickening and densifying agent prepared in Example 3 of this invention was added to the concrete and mixed at a dosage of 30% of the amount of adhesive material, replacing 15% of cement and 100% of silica fume by weight. The performance comparison of the concrete prepared with that prepared in Comparative Example 1 is shown in Table 3.

[0047] Table 3:

[0048]

[0049] As can be seen from the above case comparisons, after adding this product to different application scenarios, the slump time of the concrete inverted slump cone is longer, the electrical flux and water seepage height of the concrete are reduced, the compressive strength is improved, the compressive strength of the shotcrete is improved after 8 hours, and the impact and abrasion resistance is improved.

[0050] Therefore, the continuous graded concrete reinforcing and densifying agent of the present invention has the functions of improving concrete cohesiveness, increasing concrete density, improving compressive strength, improving impact and abrasion resistance, and reducing rebound rate in different application scenarios.

Claims

1. A continuously graded concrete reinforcing, thickening, and densifying agent, characterized in that, It includes the following components by weight: 37-65 parts titanium-containing slag powder, 34-45 parts modified silica powder, 0.5-1.0 parts water-retaining agent, and 0-20 parts accelerator and early strength agent.

2. The continuously graded concrete reinforcing, thickening, and densifying agent as described in claim 1, characterized in that, The titanium-containing slag powder has a particle size between 1μm and 40μm and a continuous gradation.

3. The continuously graded concrete reinforcing, thickening, and densifying agent as described in claim 1, characterized in that, The modified silicon micropowder has a particle size between 0.2 μm and 2 μm and a continuous gradation.

4. The continuously graded concrete reinforcing, thickening, and densifying agent as described in claim 1, characterized in that, The particle size of the accelerator is between 0.05μm and 0.4μm, and the particle size distribution is continuous.

5. The continuously graded concrete reinforcing, thickening, and densifying agent as described in claim 1, characterized in that, The particle size of the reinforcing, thickening, and densifying agent is between 0.05 μm and 40 μm, with a median diameter of approximately 3-7 μm, and its upper limit for particle size distribution is [missing information]. The lower limit of the gradation is y(x) is the cumulative throughput for particle size x; x is the current particle size in μm.

6. The continuously graded concrete reinforcing, thickening, and densifying agent as described in claim 1, characterized in that, The modified silicon micro powder is a silicon micro powder that has been mechanically and dry-modified using titanate as a powder surface modifier.

7. The continuously graded concrete reinforcing, thickening, and densifying agent as described in claim 1, characterized in that, The water-retaining agent is a core-shell type nanocomposite water-retaining agent with nano-CaCO3 core, and the coagulation-accelerating and early-strength agent is a nucleation type early-strength agent mainly composed of nano-aluminosilicates.

8. Application of a continuously graded concrete reinforcing, thickening and densifying agent in concrete.

9. The application as described in claim 8, characterized in that, Its dosage is calculated based on the proportion of cement in concrete, ranging from 5% to 30%.

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