Studies on the Compressibility and Shear Strength Behaviour of Fly Ash and Slag Mixtures

This paper investigates on the mechanical characteristics (compressibility and shear strength) of fly ash/ground-granulated blast-furnace slag (GGBS) mixtures at various mix ratios using consolidation and direct shear tests, respectively. The consolidation studies were done at a reduced duration of load increment. The compressibility behaviour has been found to improve with increase in GGBS content. Direct shear test results showed an increase in angle of internal friction with GGBS content. Microstructural studies using SEM reveal insight information about the effect of particle morphology responsible on compressibility and shear strength behaviour. It is proposed from the findings of this investigation that fly ash/GGBS mixtures have utilisation potential in the construction of embankments or structural fill which will undergo very small settlement.