As people continue to deepen their research on concrete admixtures, the future development of concrete admixtures will develop in the direction of composite admixtures. In order to better analyze the impact of different factors on the performance of water-reducing admixtures, adding an appropriate amount of water-reducing admixtures to concrete can not only effectively improve the workability of fresh concrete and reduce slump loss, but also significantly reduce water use The amount increases the strength, thereby greatly reducing the possibility of problems such as concrete cracks. Adding an appropriate amount of water reducing agent to concrete can not only effectively improve the workability of fresh concrete and reduce slump loss, but also significantly reduce water consumption and increase strength, thus greatly reducing the possibility of concrete cracks and other problems. When used, the water-reducing agent may experience sudden changes in quality. If not correctly understood, it will easily cause serious concrete quality problems.
Reasons for sudden changes in the performance of water-reducing agents and precautions for use
There are roughly the following types of sudden changes in the quality of water-reducing agents:
1. Sudden changes in water-reducing rate .
When the water reduction rate suddenly becomes large, the amount in the original mix ratio is too large, which will cause serious bleeding, segregation, and large-area cracking after condensation and hardening of the concrete. When the water reduction rate is If it suddenly becomes smaller, the water consumption will increase, the water-cement ratio will increase, the strength will decrease, and the working performance of concrete will decrease. Therefore, in addition to the overall inspection of each batch of water-reducing agents entering the market, quality monitoring during the production process must be strengthened. Once the above situation occurs, the cause must be quickly identified and the amount of water-reducing agent adjusted.
2. The content and variety of air-entraining components in the water-reducing agent suddenly change.
This situation may cause the air content in the concrete to be too high, causing a significant decrease in the strength of the concrete; the air content to be too low, the workability of the concrete will become poor. Engineers should frequently check the air content or bulk density of concrete. If significant changes occur, they need to notify the admixture supplier to make adjustments.
3. The slump-preserving component added to the water-reducing agent suddenly changes.
It may cause the concrete slump to lose too much over time and fail to meet construction requirements.
4. The type and dosage of the retarding component in the water-reducing agent suddenly changes.
It may cause the concrete setting time to be too long or too short, or it may cause the concrete slump to increase over time, failing to meet construction requirements, affecting the early mechanical properties of concrete, etc. Countermeasures: Frequently check the concrete setting time and slump loss over time. </p
微信扫一扫打赏
Chinese