Abstract:

The shrinkage deformations of specimens of concrete added with different amount of silica fume with onesided drying at various depths from drying surface were investigated by fixation of several groups of displacement sensors. The relative humidity changes of concrete at various depths were also studied using embedded humidity sensors. The results showed that the shrinkage and the humidity reduction in the internal layer of concrete are markedly lower than those in the nearsurface layer. adding silica fume to concrete reduces significantly the shrinkage difference from drying surface to internal layer of concrete and the humidity gradient. Under the onesided drying condition, there are good linear relationships between the shrinkage and the humidity at various depths in concrete. However, the shrinkage in the surface layer of concrete is lower than that in the internal layer at the same relative humidity.

Key words: civil engineering, concrete, silica fume, one-sided drying, shrinkage, non-uniform distribution