The environmental impact, particularly the significant emission of greenhouse gases associated with the manufacture of ordinary portland cement (OPC) has catalyzed studies on the use of several environmentally benign alternate materials as partial OPC replacements. Fine limestone powder is one such material that has shown to be a viable partial OPC replacement material. A clear understanding of the effects of limestone replacement in combination with fly ash or metakaolin on the fresh and hardened properties has facilitated new strategies to proportion binder formulations which show comparable or superior properties to traditional OPC formulations.
Limestone can be interground with OPC clinker in the cement manufacturing process or blended with the cement during the concrete batching process. Improved particle packing, fine limestone acting as nucleation sites for reaction product formation, and consequently better properties are obtained. Studies on the use of fine limestone as a partial cement replacement material, and its synergy with other aluminate-bearing materials such as fly ash, metakaolin, and slag have been investigated in great detail. The hydration process in such
systems, mechanical property development, and rheological characteristics are elucidated in many of our publications. Through the use of mathematical models and accelerated transport experiments, we have also established the beneficial effects of limestone containing ternary blends on concrete durability.