Effects of ground granulated blast furnace slags (GGBS) and lime/ activated magnesium oxide on engineering properties of sand

This paper discusses the use of Ground Granulated Blast furnace Slag (GGBS) and lime blends for soil stabilization. A range of tests were performed to investigate the properties of stabilized sands, including unconfined compressive strength (UCS), soaking in artificial seawater, and microstructural analysis using Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDX) for elemental analysis of the soaked samples. The influences of binder content, lime content and curing period were addressed. The use of GGBS significantly increased the UCS of lime-stabilised sand. An increase in binder content increased the UCS of the test specimens. The increase in lime content increased the UCS of some of the test specimens. Lime-stabilised sand after 28 days of soaking in artificial seawater showed minimal disruption of its original rigid form. The microstructural analysis concluded the formation of needle-like crystalline structures which were found to be ettringites randomly distributed on a few of the soaked samples in the artificial seawater. The elemental analysis obtained from EDX suggested the consumption of Ca2+ during the formation of ettringites. The growth conditions of the ettringite observed is determined primarily by the lime content and calcium content in the lime-activated GGBS specimens.Bachelor of Engineering (Civil