Dear reader perhaps we have read our post “quality of water for concrete mix”. There we have discussed about biological and chemical content of water that may impair concrete properties.
Sometime water may be hard or they may be contaminated. The contamination that are due to detergent from industry or house hold water may affect air content in concrete. Even a little contamination due to detergent may affect air entrainment. In case of hard water, there may have also reduction in air content.
There have influence of temperature in performance of air entraining admixture too. When temperature of concrete mix is increased air content is decreased. With an increase in air temperature from (700F-1000F), the air content decrease up to 25%.
The opposite influence is observed, when temperature is dropped from (700F~400F), the air content increase up to 40%.
From the above discussion we can conclude that the application of air entraining agent must be adjusted when temperature of concrete is changed.