Concrete quality can now be reliably evaluated in the field by determining the water-cement ratio of the mix and using that information to estimate the 28-day compressive and flexural strengths--all in less than 15 minutes. Improvements in the method have been achieved by automating the process: incorporating commercially available analytical test units into a system of equipment known as the Concrete Quality Monitor (CQM).
With other methods of evaluating strength there is a risk of placing defective concrete before the evaluation has been made, and a possibility of expensive replacement costs. The CQM is the only type of system that determines both the water and cement content of fresh concrete within 10 to 15 minutes. It takes only one day's training to learn to use the CQM. The method relies on instrumental analysis and associated small quantities of pre-packaged reagents. It is easy to operate and, due to the automated measuring system, has virtually eliminated operator subjectivity.