Study on diffusibility of chlorine ions in cement-based cementitious materials
WANG Xin,CUI Su-ping,YAN Bi-lan China Building Materials Academy,Beijing 100024,China
By means of the testing technologies such as XRD,SEM,mercury intrusion method,the diffusibility of chlorine ions in cement mortar was analyzed in terms of clinker mineral composition,content and types of gypsum,content of admixture,optimization matching of admixture and particle size distribution,the main factors and mechanism that influenced the diffusibility of chlorine ions in cement mortar were also analyzed combined with microstructure analysis of 28d hydration product and pore feather of dehydrated cement paste. The results showed that the ratio of the porosity larger than 100nm to total porosity had a good relativity with diffusion coefficient of chlorine ions in cement,and it was a main influence factor. The new point of view was presented that cement composition feature parameter (T0) could be used to represented diffusibility of chlorine ions in cement.