Segregation often occurs during the use of concrete, so what is the cause of segregation? How to prevent it?
1. Causes of concrete segregation
1. Segregation caused by poor quality of concrete
Concrete is the most critical component of concrete. The quality of concrete must be decided immediately. Properties of concrete. In addition, segregation is also closely related to concrete.
Cement fineness is one of the most critical parameters to consider the properties of concrete. It expresses the size of concrete. The finer the concrete, the larger the area after fusion with water, and the stronger the specificity. In addition, if the alkali content is high and low, it is easy to cause segregation problems in concrete. Therefore, after segregation occurs in concrete, the first thing that comes to mind is to check whether the quality of the concrete has changed.
2. Segregation of stones
The combination of coarse sand and fine sand can make the gaps inside the concrete smaller, which can better ensure the fluidity of the concrete and also Concrete segregation problems can be avoided. Secondly, if the mud content in the sand and gravel is too high, it will also make the performance of the concrete worse, and eventually cause concrete segregation.
3. Segregation is caused by admixtures
There are many types of admixtures with different effects. For example, water reducing agent is used to reduce the amount of raw water used in concrete, which can not only ensure the circulation performance of concrete, but also effectively prevent segregation. Since the water content in concrete is reduced, the probability of concrete segregation will also be greatly reduced. However, if the wrong type of superplasticizer is used, or the wrong amount is used, it will also cause segregation problems in concrete. The use of water-reducing agent must be based on the specific situation, and the demand for water-reducing agent cannot be increased or reduced casually.
4. Segregation caused by machinery and equipment
During the processing of concrete, the amounts of various raw materials used are strictly formulated. If more or less of a certain type of raw material is used, the properties of concrete will be changed immediately. Mechanical failure is likely to cause concrete segregation.
2. Damage caused by concrete segregation
After concrete segregates, the fluidity will be reduced, resulting in a reduction in the conveying performance of the concrete pump; after the segregated concrete hardens, it is very easy to become dusty and dusty. Dust may cause substandard construction quality. In addition, after the separation of concrete, the stone gaps are too large, which will cause bubbles in the concrete and lead to honeycombing. Or, the strength of the concrete after hardening is insufficient, which can easily cause problems such as cracking.
3. Prevent concrete segregation
First of all, it is necessary to strictly control the quality of concrete raw materials, especially after changing cement manufacturers, or new concrete, samples must be retained Examine the properties of concrete. For stone materials, the water content and mud content must be strictly monitored.
During the processing process, the mixing ratio must be strictly implemented to produce concrete, and the operator cannot change the amount of certain types of raw materials in the concrete at will. During the transportation process, no one can add water or other preservatives to the concrete casually to ensure the integrity of the concrete quality. </p