STUDY ON THE HYDRATION HEAT OF MASS CONCRETE MIXED WITH UREA BY FEM ANALYSIS

Abstract

Recently, studies on the reduction of concrete thermal crack using endothermic property of Urea have been reported. In these studies, various physical performance tests of Urea mixed concrete namely reduction of concrete hydration heat, reduction of drying shrinkage and recovery of compressive strength on the long-age were performed. However, there is no interpretive study for the Urea mixed concrete. In this study, adiabatic temperature rise and compressive strength tests were performed. And then, hydration heat of practical structure sized model was analyzed by FEM using experiment results. Results of experiment showed that reaching time was delayed 2.66 hours, initial temperature and maximum temperature decreased 0.29℃ and 0.33℃, respectively. Results of hydration heat FEM analysis confirmed that reaching time was delayed 1.86 hours, hydration heat was decreased 1℃ and thermal crack ratio of 0.1 with Urea mixing ratio of 1% was achieved.