Abstract:By using a self designed loading device, the chloride ion permeability of plain concrete with different mineral admixtures(slag, fly ash, silica fume) under sustained uniaxial compressive load were studied, and the corresponding mathematical models were proposed as well. The results show that the sustained uniaxial compressive load has a significant impact on the permeability of concrete and the relationship between chloride ion diffusion coefficient and stress rate approximately agrees with the mathematic model of parabola. Separate addition of different mineral admixtures into concrete can improve its resistance to chloride ion permeation, and the effectivness of silica fume is the best, followed by slag, fly ash is the worst. The chloride ion diffusion coefficient decreases with increasing mineral admixture content by the negative exponential function. For concrete mixed with mineral admixtures, the permeability and the compressive strength does not have a good correlation.