Once again, the ready-mixed concrete industry faces the annual battle over testing. There is always the expectation that the problem is not with the concrete but with the testing.
A 1000 psi drop in 28-day concrete cylinder strength can be expected every year in many parts of the southern half of the United States and through the Central Plains starting in May. Strengths will be down until October or November. Many contractors will experience delays while the concrete is investigated to determine if it meets the specifications.