Improve Concrete Performance Of Chloride Ion

In this paper, the "Equalling Method", the "Leaching Method", the "AgNO3 Coloring-Leaching Method" and the "Evaporable Water Method" are mainly used to analyze the chloride ion binding capacity of paste, including chloride added into paste and chloride present in environment, the diffusion orderliness of chloride ion in mortar and the porosity of mortar. Effects of the paste composition and experimentation condition on chloride ion binding of cement paste and the diffusion of chloride ion in mortar are investigated. The difference between the effects of the paste composition on the two types chloride binding is compared, and the different mechanism of the two types chloride binding is analyzed. At the same time, the relativity between the diffusion orderliness and the chloride binding capacity of paste, the porosity of mortar are analyzed.Results indicate that chlorides binding of unit paste can be improved by addition of fly ash and slag. Compared with pure cement paste, the increase is about 20%. However, compared with fly ash and slag, the chloride ion binding of unit paste can be greatly enhanced by addition of the adsorbent. Furthermore, coupling with slag and the adsorbent, chloride binding of unit paste can be further enhanced. Compared with pure cement paste, the increase is about 100%. The capability of chloride ion binding of unit paste goes up with the increase of the initial Cl~- concentration and the temperature. GGBS and the adsorbent both can reduce the diffusion depth and the free chloride content of mortar, and the effect of GGBS is prominent.The diffusion orderliness of chloride ion in mortar is more relative with the porosity of big pore thanthe porosity of general pore and the capability of chloride ion binding of paste.