Experimental evaluation and statistical modeling of sustainable sisal fiber-reinforced fly ash-based lateritic concrete using response surface methodology

• Published in: Journal of Building Engineering 2024-05, Vol.84, p.108498, Article 108498
• Main Authors: Patil, Sharanabasava, Bhaskar, Ramesh, Xavier, Joseph Raj, Raja, Rajapriya
• Format: Article
• Language: English
• Subjects: 3D response surface plot; Laterite aggregate; Mechanical properties; Multi-objective optimization; Sustainable concrete
• ISSN: 2352-7102; 2352-7102
• DOI: 10.1016/j.jobe.2024.108498

This research uses waste laterite scraps as coarse aggregates in sisal fiber-reinforced fly ash-based lateritic concrete and evaluates its strength properties to create sustainable concrete. By lowering the requirement for virgin materials, its use lessens the need for granite mining, environmental contamination, and the preservation of natural resources. Using response surface methodology (RSM’s) central composite design (CCD), twenty-nine different lateritic concrete mixtures have been designed with varying input factor combinations (LA: 25%–100%, FA: 5%–20%, SF: 0.25%–1%, and SP: 1%–1.6%) with a total of 279 test specimens were cast and tested for responses like compressive, split-tensile, and flexural strengths at 28 days. The analysis of variance (ANOVA) test was performed to determine the accuracy of the mathematical models developed following the experimental results. Quadratic models were proposed due to a higher coefficient of determination (R2) for all responses. The higher addition of laterite aggregate linearly reduces fresh concrete’s workability. The compressive strength of the M30 grade concretes for 28 days increased by 11.20% when 25% of the granite aggregates were substituted with laterite aggregates. Compressive strength decreases above 25% replacement. Similarly, split tensile and flexural strengths are increased over the control mix by 10.86% and 5.88%, respectively. Multi-objective optimization was used to study the interactions between the different components and determine the appropriate mixing ratio. Considering the goals of multi-objective optimization, the optimal mix of sisal fiber-reinforced fly ash-based lateritic concrete may be produced with LA substitution of 25%, FA substitution of 10.52%, SF addition of 1%, and SP addition of 1.48%. Experimental validation was carried out with an error rate of less than 5% of the anticipated optimal data. •Sustainable concrete using waste laterite scraps as coarse aggregate.•Response surface methodology approach predicts and optimizes lateritic concrete properties.•Higher laterite content reduced workability due to the presence of kaolinite and goethite clay.•Sisal fiber significantly enhanced tensile and flexural strength in lateritic concrete.•Optimum addition of laterite, fly ash, and sisal fiber in lateritic concrete is recommended.