Determining Water Content of Fresh Concrete by Microwave Reflection or Transmission Measurement

摘要

In search of a rapid and accurate method for determining the water content of fresh concrete mixes, the microwave reflection and transmission properties of fresh concrete mixes were studied to determine the extent of correlation between each of these properties and water content. The report describes the procedures that were devised to measure these properties and the results that were obtained. The results indicated that the microwave reflectivity and transmission of fresh concrete mixes are both sufficiently correlated to water content. Since these properties can be measured very rapidly without any pretreatment of the fresh concrete samples, microwave reflectivity or transmission measurement has the potential to be a rapid, nondestructive, and reasonably accurate quality-assurance method for measuring the water content of fresh concrete mixes, especially for a large capacity ready-mix plant.