The increasing levels of carbon dioxide emissions have caused a global reconsideration of approaches to addressing global warming. One of the main contributors of these emissions is cement production, which generates high temperatures during its combustion processes. A recent development in construction industry has shown promise during formation of fly-ash based geopolymer composite, offering a potential alternative to traditional Portland cement concrete that could reduce or even eliminate its use, this research focuses on the mechanical performance of fly ash incorporated composites, especially its strength related parameters. The data for this study was obtained from tests conducted on geopolymer concrete specimen created from two different sources of fly ash, each subjected to varying concentrations of sodium hydroxide solution. The compressive strength of geopolymer concrete ranged from values typical of normal-strength concrete to those associated with high strength. The primary emphasis of this paper is on the correlation between different mechanical parameters of geopolymer concrete. Geopolymer concrete requires a combination of cement ingredients and fly ash as replacement. This research is especially relevant to developing countries as it will explore the locally produced fly ash as a raw material for production of geopolymer composite. Development of suitable geopolymer composite can be an alternate construction material for the industry and reduce reliance on conventional concrete. This will also lead to reduction in production of cement and help combat the climate change. The goal of this study is to help the achieve sustainable development goals by developing eco-friendly composite material for construction of sustainable cities.