A comparative study of different biocementation implementation methods for embankment foundation soil

In the context of sustainable ground engineering practices, biocementation has recently attracted the vivid interest of researchers worldwide. The technique utilises the natural biological process of biomineralisation (the biological production of minerals through the metabolic processes of different types of microorganisms/ plants) as a soil stabilisation method. The technique has the potential to be environmentally superior to other common chemical soil stabilisers. This study uses indigenous ureolytic micro-organisms to biocement an organic soil from the UK railway network. The paper focuses on the comparative investigation of different methods of implementation of biocementation treatments. Namely, mixing of all treatments, pressure injection and electrokinetic injection. The success of the techniques is discussed in terms of a) Unconfined compressive strength (UCS); b) calcium carbonate precipitation and c) compressibility and consolidation characteristics. It is shown that electrokinetic treatment is overall more successful as it led to higher strengths and CaCO3 contents, as well as higher stiffness of the treated soil.It also shows promise for a successful implementation of the treatments under existing infrastructure.