Influence of Microwave Treatment on Properties of Concrete with Non-Cyclic Alkanes

Abstract

Influence of exposure to microwave (MW) radiation of concrete with paraffin addition was presented. Specimens were exposed to MW after 7 and 28 days from casting. The exposure times were: 20 minutes and 40 minutes. Concretes were made with 1 and 3% addition of paraffin of the volume of concrete mixture. As a reference served concrete with no paraffin addition and concrete containing paraffin but not treated with MW. Paraffin was added in two forms: as a powder (fine paraffin) and as a granules (coarse paraffin). Influence of radiation on compressive and tensile splitting strength was tested as well as its impact on sorptivity and free water absorption. Exposure to MW radiation lowered the mean values of concrete compressive and tensile splitting strength maximum of about 24%. Sorptivity test results showed no general tendency and free water absorption has decreased maximum about 20%.