Bharti Kumari, Meghna Sharma, Satoru Kawasaki
Expansive soil poses substantial issues in civil engineering due to its poor characteristics and susceptibility to significant volume fluctuations caused by changes in moisture content. This can cause structural damage, cracking, and other risks to the superstructures. Traditional stabilization methods, such as employing cement, lime, and chemicals, have drawbacks, including high prices and harmful environmental consequences. Furthermore, the inappropriate disposal of plastic garbage continues to exacerbate environmental damage. A detailed review is carried out to explore the synergistic use of synthetic fibers generated from recycled plastics and nature-based techniques like microbially induced carbonate precipitation (MICP) for stabilizing expansive soils. The review focuses on improving the strength and reducing the swelling of soil by combining synthetic fibers with the MICP method. The long-term viability of stabilizing expansive soils with natural solutions and recycled plastic waste is also justified through insights from past studies. The limitations of MICP and waste fibers in large-scale, real-world applications are also discussed. This review focuses on MICP over enzyme-induced carbonate precipitation (EICP) due to its superior environmental compatibility and scalability. This review underscores the potential of combining MICP with recycled synthetic fibers as a sustainable and cost-effective approach for expansive soil stabilization in geotechnical engineering.