Thesis (MSc) - Cyprus International University. Institute of Graduate Studies and Research Civil Engineering

In order to reduce the amount of waste that is disposed of in landfills, concrete technology is seeing a rise in the use of alkali-activated binders made from a variety of waste and industrial byproducts. Recently, environmentally friendly materials called geopolymers have become more popular in the building sector. When fly ash, slag, or metakaolin are combined with an alkaline solution, an activating solution, these alternative binders are created. The by-products are rich in silica and alumina. In this Research Recycled aggregate is fully replaced with Natural Aggregates. Though their mechanical properties have not yet caught up to those of natural aggregates (NA), recycled aggregates (RA) are an environmentally beneficial alternative to NA in concrete. Making geopolymer concrete (GPC) in part by substituting ordinary Portland cement (OPC) with industrial byproducts is a topic of significant scientific interest. In order to enable the use of 100% recycled fine aggregate in mortar, one of the purposes of this study is to evaluate the environmental feasibility of partially replacing fly ash in geopolymer mortar with glass powder and silica fume. Creating an appropriate mix ratio for geopolymer mortar that is cured at room temperature is also one of the goals of the study. This is incorporating waste glass powder (GP), fly ash (FA), recycled fine aggregate, and silica fume (SF) into the combination. The substitution of the base material, fly ash, took place by incorporating varying proportions of glass powder and silica fume. This was done to evaluate the fresh properties, durability, and mechanical characteristics of the mortar. The ratios of alkaline liquid to binder, molarity of NaOH solution, quantities of FA and Na2SiO3/NaOH ratio were among the characteristics taken into consideration. The findings revealed that all mixes displayed considerable enhancements in flowability compared to the control mixture. The binary blends M6 and M7 demonstrated notable improvements in compressive, flexural, and tensile strengths with M7 showing the highest strength compared to the control. Meanwhile, the ternary mixture M3 showcased superior mechanical properties relative to the control mixture.