Optimization of mechanical and impact resistance of high strength glass fiber reinforced alkali activated concrete containing silica fume: An experimental and response surface methodology approach

This study explores the enhancement of high strength alkali activated glass fiber reinforced concrete (AAGFRC) through the incorporation of silica fume and glass fibers. Silica fume was added as a supplementary material to industrial by-products of slag and fly ash in varying proportions of 0 %, 5 %, 10 %, and 15 % by weight of the binder, while glass fibers were introduced at volume fractions of 0.5 %, 0.75 %, and 1.0 % to strengthen mechanical properties and impact resistance, effectively addressing the need for materials capable of withstanding impact loads. To further optimize and enhance the properties arising from the interaction between silica fume and glass fibers in AAGFRC, a series of mechanical property tests and impact resistance evaluations were conducted. After these experimental tests, Response surface methodology (RSM) was employed to systematically analyze the data and determine the optimal mix design. The experimental results revealed that incorporating 0.75 % glass fiber and 10 % silica fume into AAGFRC significantly enhanced its properties. Analysis of Variance (ANOVA) validated the findings, confirming a strong correlation between experimental data and predicted outcomes. RSM identified the graphical optimal mix of 0.81 % glass fiber and 11.47 % silica fume, which resulted in a significantly enhanced compressive strength of 86.45 MPa and achieved a high desirability score of 0.962. The synergy between glass fiber and silica fume enhances concrete performance and sustainability by incorporating supplementary cementitious materials (SCMs), reducing carbon emissions, and ensuring reliable properties. This optimized composition establishes AAGFRC as a high-performance, sustainable material for next-generation construction.