Bio‐mediated soil improvement: An introspection into processes, materials, characterization and applications

• Published in: Soil use and management Vol. 38; no. 1; pp. 68 - 93
• Main Authors: Jiang, Ning‐Jun, Wang, Yi‐Jie, Chu, Jian, Kawasaki, Satoru, Tang, Chao‐Sheng, Cheng, Liang, Du, Yan‐Jun, Shashank, Bettadapura S., Singh, Devendra N., Han, Xiao‐Le, Wang, Yu‐Ze
• Format: Journal Article
• Language: English
• Published: Bedfordshire Wiley Subscription Services, Inc 01.01.2022
• Subjects: Additives; administrative management; Archaea; bio‐cementation; Calcium; Calcium carbonate; Calcium carbonates; Carbonates; Chemical precipitation; Chemical properties; Chemicophysical properties; edaphic factors; Eukaryotes; eukaryotic cells; Geochemistry; Geotechnical engineering; Geotechnology; microbially induced carbonate precipitation; Microorganisms; Momentum; Raw materials; Soil; Soil engineering; Soil environment; Soil improvement; Soil mechanics; Soil properties; Soils; ureolysis
• ISSN: 0266-0032; 1475-2743
• DOI: 10.1111/sum.12736

For a long time in the practice of geotechnical engineering, soil has been viewed as an inert material, comprising only inorganic phases. However, microorganisms including bacteria, archaea and eukaryotes are ubiquitous in soil and have the capacity and capability to alter bio‐geochemical processes in the local soil environment. The cumulative changes could consequently modify the physical, mechanical, conductive and chemical properties of the bulk soil matrix. In recent years, the topic of bio‐mediated geotechnics has gained momentum in the scientific literature. It involves the manipulation of various bio‐geochemical soil processes to improve soil engineering performance. In particular, the process of microbial‐induced calcium carbonate precipitation (MICP) has received the most attention for its superior performance for soil improvement. The present work aims to shape a comprehensive understanding of recent developments in bio‐mediated geotechnics, with a focus on MICP. Referring to around one hundred studies published over the past five years, this review focuses on popular and alternative MICP processes, innovative raw materials and additives for MICP, emerging tools and testing methodologies for characterizing MICP at multi‐scale, and applications in emerging and/or unconventional geotechnical fields.