Abstract: This study was conducted to research the effect of the pre-curing process on the compressive strength of meta-kaolin-based-geopolymers. Pre-curing is a process in which the green geopolymer is left at room temperature for a certain period of time prior to high-temperature curing and it is known to be effective for increasing the strength of the geopolymers. In this experiment, the compressive strength of geopolymers was measured according to various pre-curing conditions. Various properties of geopolymers fabricated with a pre-curing process were analyzed using UTM, XRD, SEM, FT-IR and a Gilmore needle tester. It was found that pre-curing was effective in improving the compressive strength of meta-kaolin-based-geopolymers. For example, the specimens prepared by pre-curing for 6 days during a total curing process of 7 days showed the highest compressive strength and the specimens prepared by pre-curing for 13 days during a total curing process of 28 days showed the highest compressive strength, 76.3 MPa which is 2.4 times higher than that of specimen made without pre-curing process. Several crystal phases such as zeolite, cancrinite and Calcium-Aluminium-Silicate-Hydrate (denoted as C-A-S-H) were found in the geopolymer gel and the compressive strength of the geopolymer increased with pre-curing time and amount of cancrinite and C-A-S-H phases.
Byeongguk Kang, Kangduk Kim and Seunggu Kang, 2019. Characterization of Meta-Kaolin based Geopolymers Produced by Pre-Curing Process. Journal of Engineering and Applied Sciences, 14: 1443-1450.