Performance of self-compacting concrete incorporating recycled concrete fines and aggregate exposed to sulphate attack

The present study investigates the performance of self-compacting concrete (SCC) and self-compacting sand concrete (SCSC) incorporating recycled concrete fines and aggregate under different sulphate environments. Similar mixtures incorporating natural aggregates and natural pozzolana were also tested for comparison. Different sulphate attack regimes (i.e. fully submerged and immersion-drying cycles) were applied. Compressive strength development/degradation under sulphate attack was monitored for all tested mixtures. Results indicate that the use of recycled materials did not significantly affect the strength development with respect to mixtures with natural materials. Moreover, mixtures incorporating recycled concrete aggregate and fine recycled concrete exhibited a better sulphate resistance behaviour than those with natural aggregates and natural pozzolana. In conclusion, the quality of the used recycled materials is a key factor in producing green and sustainable self-compacting concrete.