OPTIMIZING THE LIGHTWEIGHT STEEL FIBRE REINFORCED BACTERIAL CONCRETE WITH NANO-SILICA AND COCONUT SHELL AGGREGATES USING TAGUCHI METHOD

Authors

• Damodaran Pooja, Department of Civil Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, SIMATS, Chennai, Tamil Nadu, India 602105
• Mayilsamy Yuvaperiyasamy, Department of Mechanical Engineering, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, SIMATS, Chennai, Tamil Nadu, India 602105Follow

Corresponding Author

Mayilsamy Yuvaperiyasamy

Subject Area

Civil and Environmental Engineering

Article Type

Original Study

Abstract

Concrete is essential for construction due to its high strength and durability. It supports most modern infrastructure globally. Cement production is a major source of CO₂ emissions, posing serious environmental concerns. Additionally, the rising demand for concrete is straining the limited supply of essential raw materials, such as aggregates. Researchers are examining alternative materials to improve Sustainability while maintaining structural strength to address these issues. This research aims to improve concrete performance by enhancing cement durability with nano-silica. Coconut shell, an agricultural by-product, functions as an eco-friendly alternative to conventional coarse aggregates, alleviating their scarcity. Microbiologically induced calcium carbonate precipitation (MICP) was employed to develop a lightweight steel fibre-reinforced bacterial concrete. The mix incorporated Bacillus subtilis at varying concentrations (10⁶, 10⁷, and 10⁸ CFU/ml), nano-silica at 1%, 2%, and 3% by weight of cement, and water/cement ratios of 0.40, 0.42, and 0.44. Coconut shells were used entirely in place of coarse aggregates, and steel fibres were added at 1%, 2%, and 3% by weight of cement to improve strength. The Taguchi method and an L₉ orthogonal array were used to identify optimal conditions for enhancing compressive strength and durability. A scanning electron microscope (SEM) was used to analyse the control and optimised mixes. The results showed that using 2% nano-silica, 100% coconut shell aggregate, Bacillus subtilis at 10⁷ CFU/ml, and a 0.42 water/cement ratio significantly improved strength and durability. SEM analysis revealed calcium carbonate (CaCO₃) precipitation in the optimised mixture, confirming the treatment’s effectiveness.

Keywords

Analysis of variance; Bio-concrete; Lightweight aggregate; Optimisation; Sustainable; Water absorption

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.

Recommended Citation

Pooja, Damodaran and Yuvaperiyasamy, Mayilsamy (2026) "OPTIMIZING THE LIGHTWEIGHT STEEL FIBRE REINFORCED BACTERIAL CONCRETE WITH NANO-SILICA AND COCONUT SHELL AGGREGATES USING TAGUCHI METHOD," Mansoura Engineering Journal: Vol. 51 : Iss. 3 , Article 10.
Available at: https://doi.org/10.58491/2735-4202.3464