In this study, autogenous and drying shrinkage of early age concretes with and without silica fume are experimentally investigated. The water loss due to self-desiccation in autogenous shrinkage specimen and the relative water content change due to evaporation in drying shrinkage are also investigated. Variables adopted for this research are water-cement ratio, amount of silica fume and curing condition before drying, i.e. either exposure to drying environment immediately after demolding or after curing in water for 7 days.
Through this research it was found that low water-cement ratio concrete without silica fume exhibited large autogenous shrinkage but small drying shrinkage. Presence of silica fume, however, increased autogenous and drying shrinkage of concrete compared to reference portland cement concrete with same water-binder ratio. Furthermore, the rate of water loss was more rapid than that of length change in autogenous shrinkage specimens, however, the relative water content change was similar to length change and higher in the higher water-cement ratio concrete.
