Mix design, compressive strength and resistance to elevated temperature (500°C) of self-compacting concretes containing limestone and quartz fillers

Self Compacting Concrete (SCC) specimens with limestone (L) and quartz (Q) powders were formulated. The influence of the type of the powder on the properties of fresh and hardened concrete was evaluated. Dense packing theories were used for mix design of samples. The equation of Fuller and Thompson for particle size distribution (PSD) of aggregates was modified with considering fine particles and a proper PSD curve was obtained for SCC. Experimental results showed that this method needs use of less powder content and results in higher strength/cement ratio compared to traditional mixing methods. No significant difference was observed between the compressive strengths of specimens containing limestone (L-specimens) and quartz (Q-specimens) powders, with similar proportions of materials. The residual compressive strength of specimens was examined at 500°C and contradictory behaviors were observed. One Q-specimen suffered from explosive spalling, while no spalling was occurred for L-specimens. On the other hand, the residual strength of remained Q-specimens showed considerable increase compared to L-specimens. The results show the necessity for more detailed investigations considering different effective parameters.