High temperature exposure of metakaolin-geopolymer stabilized compressed earth blocks: durability and performance indicators
摘要
In recent decades, there has been a resurgence of interest in earth-based materials, primarily because of the pursuit of alternatives to Portland cement in construction. Although these materials exhibit favorable performance characteristics, especially when stabilized with inorganic mineral binders such as geopolymers or even lime, some of their properties remain inadequately understood. Specifically, uncertainties persist regarding the performance of earthen bricks during emergencies, such as fires, and their feasibility as refractory materials for high-temperature applications. To this regard, this study focused on the durability of compressed earth blocks (CEB) stabilized with a geopolymer binder when exposed to high temperature. The CEBs were produced using lateritic soil (Kamboinsin quarry) and metakaolin (MK) obtained by calcining kaolinitic clay (Saaba) at 700 °C. The soil-MK mixture was moistened according to the optimal rate determined by the Proctor test, with a ratio of 0.8 between the alkaline solution (12 M) and the MK mass. CEBs stabilized with 10–20% geopolymer binder (CEB_G) were molded