Rapid test methods for the evaluation of concrete properties.

PDFTech ReportDOT-FH-11-8876Properties of materialsConcreteTestingMicrowave devicesWater cement ratioEvaluationAccuracyOregonOregon State Highway DivisionBeecroft, Donald E.Dominick, Richard L.Oregon State Highway DivisionUnited States. Federal Highway AdministrationUS Transportation CollectionThe objective of the project was to place a CERL/Kelly-Vail testing unit and a microwave oven in the field to perform tests of plastic concrete on construction projects.The CERL/K-V tests were to determine water and cement content of the concrete and were evaluated as a method of predicting 28-day concrete strength.Although the water and cement contents can be determined with a reasonable degree of accuracy, there are too many variables involved in the field to accurately predict strength.The microwave oven used in the defrost mode is a fast and accurate method to determine water content with a minimum of equipment and operator training