Q: The specifications for entrained-air content always include both minimum and maximum limits. I know that having too little entrained air reduces the concrete’s resistance to freeze/thaw and deicer damage. But what if the air content exceeds the maximum by a percent or two? How would that affect the concrete?
A: The major effect of too much air is a reduction in concrete strength. Each percent increase in air content can reduce compressive strength by 2% to 6% for moderate-strength concrete. The degree of strength loss depends on the cement, admixtures, and other concrete ingredients used.