Use of Microwave Oven to Determine Water Content of Fresh Concrete.

摘要

The purpose of this study was to investigate an alternative procedure for determining the water content of fresh concrete to replace or provide an alternate to the method now used in evaluating concrete mixer performance. A series of laboratory tests was conducted in which a microwave oven was used in parallel with an electric hot plate. Mortar samples of known water content and mortar samples sieved from concrete mixtures were dried in the microwave oven and on the hot plate. Water content was calculated and the results obtained through use of the two methods were compared. The results obtained indicated that a microwave oven is satisfactory for use in determining the water content of mortar samples taken from fresh concrete for concrete mixer performance tests. On the basis of the tests conducted, it is recommended that the microwave oven be designated as an alternate drying apparatus in the method of test for evaluating concrete mixer performance. (Author)