Introduction of Microbial Biopolymers in Soil Treatment for Future Environmentally-Friendly and Sustainable Geotechnical Engineering

TLDR

Soil treatment in geotechnical engineering traditionally relies on cementitious binders, but rising demand for environmentally friendly alternatives has spurred interest in biopolymers, which are microbially induced, high‑tensile, innocuous, and eco‑friendly. The paper reviews recent biopolymer applications in geotechnical engineering and calls for further research to ensure practical implementation, reliability, and durability. The review discusses soil–biopolymer interactions, strengthening mechanisms from experimental and microscopic studies, and evaluates the economic feasibility compared to ordinary cement. The study concludes that biopolymers have strong potential to replace cement as an environmentally friendly soil treatment material.

Abstract

Soil treatment and improvement is commonly performed in the field of geotechnical engineering. Methods and materials to achieve this such as soil stabilization and mixing with cementitious binders have been utilized in engineered soil applications since the beginning of human civilization. Demand for environment-friendly and sustainable alternatives is currently rising. Since cement, the most commonly applied and effective soil treatment material, is responsible for heavy greenhouse gas emissions, alternatives such as geosynthetics, chemical polymers, geopolymers, microbial induction, and biopolymers are being actively studied. This study provides an overall review of the recent applications of biopolymers in geotechnical engineering. Biopolymers are microbially induced polymers that are high-tensile, innocuous, and eco-friendly. Soil–biopolymer interactions and related soil strengthening mechanisms are discussed in the context of recent experimental and microscopic studies. In addition, the economic feasibility of biopolymer implementation in the field is analyzed in comparison to ordinary cement, from environmental perspectives. Findings from this study demonstrate that biopolymers have strong potential to replace cement as a soil treatment material within the context of environment-friendly construction and development. Moreover, continuing research is suggested to ensure performance in terms of practical implementation, reliability, and durability of in situ biopolymer applications for geotechnical engineering purposes.