Utilization of GGBS-Based Geopolymer Lateritic Soils for Sustainable Pavements

Nowadays geopolymers have been recognized as eco-friendly materials as well as potential replacement of ordinary Portland cement (OPC) and lime, which are cementitious materials with three-dimensional tetrahedral frameworks of Al and Si. This paper presents experimental investigation on compaction characteristics such as optimum moisture content (OMC) and maximum dry density (MDD) and unconfined compressive strength (UCS) of a lateritic soil chemically altered with alkali activator along with precursor as ground granulated blast furnace slag (GGBS) with varying amounts of GGBS content. GGBS was added to the lateritic soil up to 30% in increments of 5%. Scanning electron microscopy (SEM) was undertaken on the geopolymer blends to know the micro-structural behaviour and chemical compounds. The results revealed that the unconfined compressive strength (UCS) of the GGBS-based geopolymer soils improved with addition of GGBS content. The micro-structural analysis confirmed the both pozzolanic reaction and ionic exchange takes place in the alkali-activated lateritic blends. The impetus for the utilization of geopolymers can be consuming GGBS in large quantities in their synthesis with the potential to reduce the use of high carbon footprint ordinary Portland cement.