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Concrete admixture manufacturers talk about the following factors of insufficient concrete strength

Release time:

2022-01-12

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Concrete admixture manufacturer: What is the reason for insufficient concrete strength?

First, raw materials and product quality issues.

Due to the poor quality of the concrete in the factory, the insufficient strength grade of the concrete during production, or the poor activity such as improper storage and agglomeration, the strength is insufficient; the quality of the stones (sand, stone) is poor, and there are many gravel. Some gravels are made of porous flint, diabase, Basalt containing expanded clay, etc., often show poor volume reliability under the action of wet zone replacement or freeze-thaw cycle, resulting in reduced concrete strength, the high water content of organic chemical residues in stone (especially in sand) will adversely affect the solidification of concrete, thereby reducing the strength of concrete; or the high water content of sulfate will cause volume expansion, resulting in cracks and reduced strength of hardened concrete.

Concrete admixture

The quality of the mixed water is not enough. If the mixed concrete is used with swamp water with high water content of organic chemical residues, wastewater containing humic acid or other acids and salts (especially sulfates), and chemical wastewater, the physical and physical properties of the concrete will be reduced, The quality of the admixture is poor. At present, the quality of the admixture manufactured by some small processing plants is not up to standard, because the admixture leads to insufficient concrete strength, and even the safety accidents of concrete not solidifying are endless.

2. concrete mix ratio problem

Concrete is also composed of cementitious materials, water and aggregates (stone and sand), but the proportion of these ingredients directly determines the strength of the concrete. If the proportion is not appropriate, it will lead to a safety accident of insufficient strength. This element is usually in the structure. Mainly manifested in several levels.

Special tools for metrological verification are worn or maintenance management methods are not very good, and the accuracy is not enough; Improper use of mixed admixtures, blindly follow the trend, and indiscriminately mix admixtures, resulting in concrete not reaching the expected strength.

Third, the problem of concrete construction technology

The sequence of feeding to the mixer is chaotic, and the mixing time is too short, resulting in asymmetry of the mixture and damage to the strength; segregation of concrete is found during transportation, but no measures (such as re-mixing, etc.) are taken, the operation of the vehicle mold is harmful to the strength, and the concrete has been initially set when pouring concrete; segregation of concrete before casting will lead to insufficient concrete strength; insufficient temperature and environmental humidity, less dry water in the initial stage, or cold stage, resulting in slightly lower concrete strength.

Improper management method of 4. test block The finished test block is not cured according to regulations, resulting in slightly lower strength of the test block; The deformation of the sample is not repaired or replaced immediately; The size of the sample and the size of the aggregate are not suitable, there is too little gravel in the test block, and the test block is not vibrated by relevant machines.

Key words:

Concrete admixture: the following talk about some knowledge of concrete

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