Research advances in biogeotechnologies

There is a large number of microorganisms in soil and rock masses. The activities of these microorganisms can influence the physical and mechanical behaviours of soils and rocks. These microbial activities can be controlled, enhanced, and used to solve geotechnical problems. Such methods have been named as biogeotechnologies. In the last decade, the biogeotechnologies have received increasing research efforts and gained great advances. This study aims at classifying and evaluating these studies from two aspects, mechanisms and applications. From the aspect of mechanisms, microbial processes that can be adopted by the biogeotechnologies include biomineralization, biogas generation, and biofilm growth, etc. From the aspect of applications, the biogeotechnologies can be used for the strengthening of soils and rocks, sealing of water leakage, prevention or mitigation of soil liquefaction, soil erosion control, and rehabilitation of contaminated soils, etc. In addition, the construction methods, monitoring and quality inspection techniques, and environmental impacts of biogeotechnologies are also introduced.