ABSTRACT
In this study, a hybrid compound is prepared to stabilise clay soil wherein certain amount of GGBS is replaced with cement (OPC) to form hybrid alkali-activated cement (HAAC). The binder content (B) is fixed at 20% of soil and GGBS is replaced by OPC in percentages of 0,10,20,30 and 40%. Different combinations of sodium hydroxide (NaOH) with molarity 3, 6 and 9M and alkali to binder (A/B) ratio of 0.5 and 0.7 are used. The unconfined compressive strength (UCS) and pH test were conducted after 7-, 14- and 28-days curing period. The highest value of the UCS was found at the combination of 9M, 0.7 A/B ratio, with binder composition of 80% GGBS and 20% OPC after 28 days curing with strength improvement to 350 times of untreated soil (21.4 kPa). X-ray diffraction (XRD) analysis and field emission scanning electron microscope (FESEM) were carried out for microstructural analysis.
