This research explores the development and application of low-calcium (Class F) fly ash-based geopolymer concrete(GPC) as a structural retrofitting material for pavements. Traditional Ordinary Portland Cement (OPC) productioncontributessignificantly to global CO2 emissions and climate change. Geopolymer concrete, formed through the chemical activationofindustrial by-products like fly ash with alkaline solutions, offers a "green" alternative with superior mechanical propertiesanddurability. This study details the experimental investigation into the fresh and hardened properties of GPC, includingconsistency,setting time, compressive strength, flexural strength, and split tensile strength. Results indicate that GPC can achieve high early strength through thermal curing, with 28-day compressive strengths reaching up to 62 MPa. The study concludes that GPCisaviable candidate for thin white-topping (TGC) and ultra-thin white-topping (UTGC) applications, providing a sustainableandlong-lasting solution for pavement upgradation.. Keywords: ETABS, Blast Load, Earthquake load, Base shear, displacement