Effects of Multiple Precursors on Bond Strength and Flexural Performance of Ambiently Cured on Geopolymer Concrete

Abstract

The present study investigates the bond strength and flexural behavior Of Geopolymer-based Reinforced Concrete (GPRC) beams to assess their suitability as sustainable alternatives to conventional concrete structures. Geopolymer Concrete (GPC) prepared with industrial byproducts, Fly Ash (FA), Ground Granulated Blast Furnace Slag (GGBS), and Silica Fume (SF), is environmentally friendly due to its significantly reduced carbon footprint. Tests involved an extensive set of experiments on GPRC beams to determine mechanical properties, steel–GPC interface BS, and flexural behavior. Experimental results are analyzed here using critical structural performance parameters such as crack initiation-propagation, failure modes, ultimate load-carrying capacity, moment versus deflection, strain response, end rotations and ductility ratios. For mixes GP30M4, GP50M4, and GP70M4 with hidden reinforcement, 12-mm-diameter rebars replaced by 10-mm-diameter rebars indicated an improvement in BS of 3.82%, 5.61%, and 6.51%, respectively. Similarly, in the case of 10-mm-diameter reinforcement, the BS for mix GP70M4 exhibited up to a 69.12% increase compared to mix GP30M4. Similarly, the ultimate load-carrying capacity of GP70M4 beams showed an 8.79% increase compared to GP30M4 beams. A higher initial deflection was observed in GP30M4 beams because of the diminished modulus of elasticity, reflecting the aspect of crack control; however, these features are favorable in the case of higher-grade concrete. In conclusion, GP70M4 GPRC provided BS comparable to or even superior to that of GP30M4 GPRC, while tests related to flexure showed improved capacity and ductility. Outcomes confirm the structural efficiency of GPC concrete and recommend its application as an environmentally green option.