Abstract:In order to study the reaction level of the alkali activated metakaolin/ GGBFS system, the content of different gels in the metakaolin/GGBFS system need to be determined. In this paper, the dissolution rates of alkali activated metakaolin/GGBFS in hydrochloric acid with various pH values were investigated, and XRF, XRD and FTIR were used to analyze the raw metakaolin and the hydrochloric acid insoluble of metakaolin-based geopolymer. It is found that the hydrochloric acid insoluble of metakaolin-based geopolymer is metakaolin which is unreacted when the pH value of hydrochloric acid is from 0 to 2. Thus the geopolymerization reaction level of metakaolin can be determined based on the content of hydrochloric acid insoluble. Under the present alkali activation environment the hydration reaction of GGBFS is nearly completed. The acid dissolution tests of alkali activated metakaolin/GGBFS show that the addition of GGBFS increases the geopolymerization level of metakaolin in most cases. With a certain GGBFS content, the reaction level of metakaolin decreases with the increase in activator modulus, and increases with the increase in liquid/solid ratio of system, of which promotion impact is more significant with a fewer GGBFS content. The reaction level of metakaolin increases with the increase in GGBFS content when the activator concentration is low, while increase first and then decrease when the activator concentration is relative high. The GGBFS content corresponding to the highest reaction level of metakaolin is gradually reduced with increase in activator concentration.