Autogenous shrinkage of concrete containing granulated blast-furnace slag

This paper presents the experimental results and prediction model for the autogenous shrinkage of concrete made with various water-to-cementitious materials ratios (w / cm) ranging from 0.27 to 0.42 and granulated blast-furnace slag (BFS) in the range of 0% to 50% by mass of the total cementitious materials. Test results showed that BFS concrete exhibited greater autogenous shrinkage than ordinary concrete with no BFS with the same w / cm, and that the higher the BFS content, the greater the autogenous shrinkage. At the same content of BFS, the increasing rate of autogenous shrinkage is affected by the w / cm; the lower the w / cm, the smaller the increasing rate of autogenous shrinkage. Based on the test results, a prediction model for autogenous shrinkage was proposed. In particular, an effective autogenous shrinkage that is a realistic shrinkage strain responsible for stress development was introduced in the model. It was determined by taking into account the characteristics of ultrasonic pulse velocity evolution in concrete. This prediction method for autogenous shrinkage may be effectively used to estimate the stress induced by autogenous shrinkage.