The Effect of Various Contents of Nano- Lime on The Properties of Self-Compacting Geopolymer Concrete Containing Micro-Steel Fibers

Abstract

The high carbon footprint of cement manufacture is the main disadvantage of Portland cement concrete, leading to contamination of the environment. Self-compacting geopolymer concrete (SCGPC) can effectively replace plain cement concrete in the construction sector for a sustainable environment. The need for high-performance concretes and green construction is rising day by day. This study has endeavored to investigate the effect of incorporating nano-lime (NL) particles at various contents of (0%,1%,2%, and 3%) by mass of calcined kaolin clay (CKC) on characteristics of fresh (flowability and passing ability), mechanical (the strengths of compression and flexural), and durability (porosity, and water absorption) for SCGPC reinforced with micro steel fibers based on CKC to enhance its performance. Three SCGPC mixes were made utilizing NL at 1%, 2%, and 3% as a partial replacement for CKC; however, an additional mix was made with no NL. The mixes had a fixed total binder quantity (484 kg/m3) and a constant quantity of micro-steel fibers 0.5% by volume. The findings showed that adding NL had a negative effect on fresh characteristics, though the mixes still satisfied the required criteria. However, With the addition of NL, especially at 2% content, the mechanical and durability characteristics of SCGPC are considerably enhanced. Applying this amount of NL results in a 1.9 % reduction in the slump flow; however, it increases compressive strength by 20.95 %, 27.27%, and 11.91% for 3,7 and 28 days, respectively, and flexural strength by 17.41 % for 28 days. It also reduced the porosity of the SCGPC specimens and significantly improved the specimens' resistance to water absorption. Based on the findings of present investigation, the recommended content of NL to be applied in SCGPC for the best performance is 2%.