Strength and durability of cementitious binder produced from fly ash-lime sludge-Portland cement

In this paper, investigations have been undertaken to produce cementitious binders by blending 61.1-70% fly ash with calcined phosphogypsum, hydrated lime sludge, Portland cement and chemical activator in different proportions. The results show that strength development of binders takes place through formation of ettringite, C-S-H and wollastonite. The durability of cementitious binder has been studied by its performance in water and by accelerated aging, i.e., alternate wetting and drying as well as by heating and cooling cycles at temperatures from 27 to 50 degrees C. The results indicate that the strength of the binder decreased with increasing cyclic studies at different temperatures. The maximum fall in compressive strength has been noted at 50 degrees C.