Thermo- mechanical properties of alkali-activated slag–Red mud concrete

This study conducts an experimental programme to investigate the possibility of utilising a binary combination of red mud (RM) and slag in the form of alkali-activated slag-RM (AASR) as a useful material for application in jointed plain concrete pavement (JPCP). Slag was replaced with RM at levels of 10, 20, 30, and 40% by weight, and the mechanical, thermal and dimensional stability properties of the mixtures were measured at various ages. The results show that mechanical strength was reduced with increasing RM. Samples of AASR concrete with 30% RM had the best thermal properties with increases in thermal conductivity and specific heat of 9% and 5%, respectively, over those of neat alkali-activated slag (AAS) concrete. The drying shrinkage of AASR is high and samples with 30% RM had the highest drying shrinkage values of 1.90 and 3.95 times those of neat AAS and ordinary portland cement (OPC) concretes, respectively.