The effect of sulfate ion diffusion on the structure of cement stone

Abstract This paper studies sulfate ion diffusion into cement stone. The penetration of SO 4 ions into the material is followed experimentally by keeping cement paste specimens in an aqueous solution of 0.515% Na 2 SO 4 for different periods of time. The depth of sulfate ion penetration is estimated by solving a non-steady equation of mass transfer, considering chemical reactions which take place in the material and experimentally determining the diffusion coefficient. Material structural response to sulfate diffusion is indirectly followed by determining the change in time of the cement stone compression strength and total porosity.