2010 Volume 66 Issue 4 Pages 520-527
The long-term durability against leaching is necessary and currently treated as an important issue, and there are many investigations on the evaluation of the durability against leaching. Especially, many researches have been reported with using the numerical analysis for deterioration due to leaching. On the other hand, the electrical treatment, which can accelerate the deterioration due to leaching with high magnification, has been used to evaluate the long-term durability against leaching. However the ion migration mechnism in the electrical treatment is different from that in the real situation. Therefore, it is important to obtain the data, such as pore structure and diffusion coefficient, after electrical treatment and evaluate the leaching behavior in the electrical treatment for the applicability. The purposes of this research were to investigate 1) the chemical alteration, such as decrease of Ca(OH)2 and Ca/Si ratio of C-S-H, 2) the phyisical alteration, such as increase of cumulative pore volume and threshold pore and 3) the feasivility of the electrical treatment for evaluation of diffusion coefficient alteration due to leaching with void ratio.As the results of this study, the important data were obtained for underestanding the leaching alteration by electrical treatment and indicating the feasivility. Espacially, the following items for using electrical treatment were obtained. 1) Decrease of Ca(OH)2 and Ca/Si ratio of C-S-H were confirmed. 2) Cumulative pore volume and pore ratio were increased. It can be said that the electrical treatment is useful for evaluating the alteration of cementitious material due to leaching. 3) The relationship between void ratio and diffusion coefficient which was obtained by electrical treatment was similar to the modeled one in previous studies. Therefore, this result were showing the applicability of the electrical treatment for leaching alteration.