Performance of water reducing agent and how to design the formula

With the development of modern engineering, the production of real estate, bridges, and other buildings is inseparable from various raw materials such as concrete. The controllability of every link in construction has been greatly improved compared to the past. As one of the most basic materials in engineering, concrete is certainly no exception, so there are additives with different functions such as water-reducing agents. What properties does water reducing agent have? Why is it so widely used?

1. Low dosage and high water reducing rate: the water reducing rate can be as high as 45%, and can be used to prepare high-strength and high-performance concrete.

2. The loss is small when the slump is light: the slump loss of ready-mixed concrete is less than 15% in 2 hours, which is extremely beneficial for long-distance transportation and pumping construction of commercial concrete.

3. Concrete has good workability: Concrete prepared with PC series high-performance water-reducing agent will not have obvious segregation or bleeding even under high slump conditions, and the appearance and color of the concrete will be uniform. . It is extremely beneficial for preparing high-fluidity concrete, self-leveling concrete, self-compacting concrete, and fair-faced concrete. When used to prepare high-grade concrete, the concrete has good workability and cohesion, and the concrete is easy to mix. 4. Small shrinkage of concrete: it can significantly reduce the shrinkage of concrete and significantly improve the volume stability and durability of concrete.

5. Extremely low alkali content: alkali content ≤0.2%.

6. Good product stability: no precipitation at low temperatures.

7. The product is green and environmentally friendly: The product is non-toxic and harmless, and is a green and environmentally friendly product, which is conducive to sustainable development.

8. Good economic benefits: the comprehensive project cost is lower than using other types of products. 8 The only disadvantage may be the adaptability problem with other cement and cementitious materials. It can be said that the quasi-water reducing agent is one of the admixtures with the worst adaptability to cement among all water reducing agent series, so before use It is very important to conduct adaptability experiments on cement and other cementitious materials to determine their performance. This is very noteworthy!

1. Based on the action mechanism of the water-reducing agent, use self-made monomers Design and synthesize a new type of salt water-reducing agent, and the optimal synthesis formula and process are: m (maleic anhydride): m (acrylic acid polyethylene glycol monoester): m (sodium propylene sulfonate) = 1 ∶3∶2.4; Use 1% K2S2O8 as initiator, reaction temperature 85℃, and reaction time 6h. The performance test results of the trial product show that the water-reducing agent has excellent dispersion ability and good workability. Its optimal dosage is 0.3%, which can significantly reduce the fluidity loss of cement slurry over time. Infrared spectrum analysis showed that the molecular structure of the synthesized product was basically consistent with the designed molecular structure.

2. High-quality high-efficiency water-reducing admixture can reduce the water-cement ratio of concrete, reduce the slump loss of concrete, improve workability, and give concrete high density and excellent construction performance. Among many series of water-reducing agents, similar water-reducing agents have a wide range of applications and have the advantages of high water-reducing properties, low slump loss, low dosage, and environmental protection. According to the current knowledge and understanding of water-reducing agents, water-reducing agents work through surface activity.

Main performance and parameters of water reducing agent:

1. The dosage is 0.5% ~ 1% of the cement weight, and the water reduction rate can reach 12% ~ 25%;

2. The early strength increases quickly, and the strength in 1 to 3 days can be increased by more than 60% compared to blank concrete;

3. The enhancement effect is obvious, and the strength in 28 days can be increased by 15% to 40% compared to blank concrete. % or more;

4. When the cement dosage is the same and the strength is similar, the slump can be increased by 100 ~ 200mm;

5. Under the conditions of similar workability and strength of concrete Under the above conditions, 10% ~ 20% of cement can be saved;

6. Using the super-mixing method, C (60) ~ C (80) concrete (mixing amount 1% ~ 2%) can be configured.

Main uses:

Suitable for ordinary concrete, high-strength concrete, early-strength concrete, fluid concrete, prestressed concrete, steam-cured concrete and special concrete.

Precautions for water reducing agent:

1. Recommended dosage: 0.5% ~ 1% (based on cement weight). The best mix ratio should be determined through trial mixing before use;

2. This product is easy to use and can be mixed in dry or wet form. The mixing time should be appropriately extended when mixing in dry form;

3. This product is packaged in 25Kg woven bags and should be stored in a dry and ventilated environment. If it agglomerates when exposed to moisture, its service life will not be affected;

4. Storage period: two years.

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