The use of concrete anti-segregation agents, what is segregation and bleeding of concrete mixtures

Table of contents of this article

• What is the segregation material?

• What does concrete segregation mean?

• What is segregation material?

• What are segregation and bleeding of concrete mixtures?

• What does segregation mean?

• What is the difference between segregation and bleeding?

What is the segregate?

The phenomenon of a certain type of molecules in a mixed material aggregating due to the same physical properties, causing the materials to separate from each other, is called segregation, and its opposite means mixing . For example, due to the different densities and particle sizes of its constituent materials, concrete mixtures tend to separate from each other under the action of gravity and external forces (such as vibration forces), causing unevenness.

What does concrete segregation mean?

Concrete segregation is a phenomenon in which the cohesion between the components of the concrete mixture is insufficient to resist the sinking of the coarse aggregate, and the components of the concrete mixture separate from each other, resulting in uneven internal composition and structure.

Usually manifested as the separation of coarse aggregate and mortar from each other, for example, dense particles are deposited at the bottom of the mixture, or coarse aggregate is separated from the mixture as a whole.

What is segregation material?

The phenomenon in which a certain type of molecules in a mixed material agglomerates due to the same physical properties, causing the materials to separate from each other, is called segregation, and its opposite means mixing.

For example, due to the different densities and particle sizes of its constituent materials, concrete mixtures tend to separate from each other under the action of gravity and external forces (such as vibration forces), causing unevenness.

What are segregation and bleeding of concrete mixtures?

The quality of concrete depends largely on the workability and homogeneity of the mixture. Well-working concrete should not exhibit excessive bleeding or segregation. The phenomenon of concrete segregation is: when the concrete mixture is piled up in a pile, the fluidity of the mixture is very good. After leaving it for a certain period of time, the slurry will secrete from the surface of the mixture and flow out to the edge, with stones exposed on the surface, and the surface of the stones will not form. Account for mortar.

The segregation of the concrete mixture can easily cause the mixture to stratify, that is, the lower layer has more stones and less slurry, and the upper layer of slurry has less or almost no stones. For concrete mixtures with the same mix ratio, the strength of segregated concrete is about 10% lower than that of concrete with good workability.

When the concrete strength is insufficient, the actual bearing capacity of the frame members decreases almost proportionally with the decrease in concrete strength. Therefore, special attention should be paid to the inspection and treatment of insufficient strength of concrete members in actual projects.

Insufficient concrete strength will have different effects on the load-bearing capacity of reinforced concrete components. It will also make the cracks in the component section wider and reduce the durability of the components. Therefore, the construction quality should be checked during the concrete construction process. For existing structures whose concrete strength is less than the design value, corresponding measures should be taken in a timely manner according to the different degrees of impact and the importance of the components to ensure that the building can meet the safety and normal use requirements.

Concrete reinforcement is a polymer solution with active silicate as the core technology. Through full penetration, its active ingredients can quickly react chemically with the free calcium in the concrete to generate crystalline colloids that fill the gaps, increase the density of the structure, and form a solid dense body on the surface of the concrete, greatly improving the strength of the surface layer of the concrete structure. and abrasion resistance, resulting in a permanently sealed, strong, abrasion-resistant, dust-free surface that is resistant to water and most industrial chemicals.

Scope of application of Guwei GWZ820 concrete reinforcing agent:

1. Painting of new and old concrete floors, walls, and columns to enhance strength, hardness, and rebound value can generally increase by 10 -25%. After 7 days of hardening and curing, it can be increased by 40%.

2. Reinforcement and repair of various concrete components or cement components that are dusty, dusty, or sandy.

3. Paint the surfaces of various new concrete components and cement products with insufficient surface strength to increase strength, hardness and extend their service life.

To deal with the problem of insufficient strength of concrete in the later stage, we should first analyze the reasons for the insufficient strength of concrete in the later stage. The water-cement ratio directly affects the later strength of concrete. When the water-cement ratio is too large, excess free water in the concrete evaporates, resulting in excessive pores in the cement slurry surface layer, reducing the compactness and reducing the strength of the concrete surface layer. In addition, if there is too much water on the surface, the polishing time of the concrete surface will be extended, and may even exceed the final setting time of the cement, causing the construction quality to be unable to be guaranteed. In addition to hydration with cement, the water in concrete also plays a role in meeting the requirements of concrete construction. During the construction process, in order to meet the schedule and facilitate construction, the slump of the concrete was amplified as much as possible, and water was even added without authorization to amplify the slump. As a result, a large amount of water bleeds from the surface of the concrete, resulting in insufficient strength of the concrete in the later stage.

For many on-site construction managers, people are often accustomed to religiously reading specifications and standards as Bibles, word for word, and never doubting their rationality. When on-site quality problems arise, more problems arise. Find the reason from your own management area. In fact, with the continuous advancement of science and technology and the continuous improvement of people's understanding, norms and standards are constantly changing and developing. If the above problems cannot be solved in time,It is unfavorable to the current progress of concrete technology and scientific development to solve it rationally and effectively. At the same time, it will have a greater impact on people's life safety.

What does segregation mean?

Concrete segregation refers to the phenomenon that the components of the concrete mixture are separated from each other, resulting in uneven internal composition and structure.

After segregation, it will affect the pouring quality of concrete, reduce the strength, and cause the accumulation of coarse aggregate, which is the separation of flesh and blood.

When mixing concrete, the mix ratio measurement should be accurate, ensuring that the mixing time is generally 90 seconds, and the slump should be controlled well. The free falling height of concrete should not exceed 2m. If the pouring exceeds 2m, chutes, slides, etc. can be used to assist. tool.

What is the difference between segregation and bleeding?

Different pronunciations, different meanings, and different usages.

Separation: (verb) ①Separate; split: fall apart~. ②Analysis; analysis.

Example: Use the word "xiang" to describe people's misfortunes and blessings. Those who are looking for an image can just write a word at random, that is, in terms of the word and analysis, all of them are extraordinary and famous in the ninth level.

Bleeding: refers to the upward movement of water before the concrete volume has been fixed but before it solidifies.

Example: The mixtures produced by various shell-making and stirring processes have a common feature, that is, the amount of bleeding is greatly reduced.