The Rheological and Mechanical Properties of High-performance Self-compacting Concrete with High-calcium Fly Ash

The paper presents test results for the high performance self-compacting concrete (HPSCC) modified by High-Calcium Fly Ash (HCFA). HCFA was used as a replacement for a part of cement in the mixture (2 types of HCFA. also activated by grinding) or as an additive to cement (also in combination with other additives as F-class ash and ground granulated blast furnace). The research has shown the negative influence of raw calcium fly ash (without grinding) added to concrete mix on its rheological properties and workability. Activation of fly ash (by grinding) improves its properties. and becomes positive as an additive to concrete mixes. The results include studies on samples belonging to classes of slump flow SF. classes of viscosity T500. rheological properties. compressive strength and flexural strength tests. The concrete mix was tested with a varying amount of HCFA (10-20-30%). as equivalent of cement. The studies have confirmed the possibility of using HCFA in new generation concretes while maintaining the assumed technological parameters for concrete mixtures. especially their workability.