Zhang Aoxi

Bio-cementation soil improvement methods are alternatives to invasive, carbon-intensive stabilisation techniques. These methods, which include microbially induced carbonate precipitation (MICP) and enzyme induced carbonate precipitation (EICP), use biogeochemical processes to drive carbonate precipitation and cement soil grains, thereby improving the material mechanical performance. Sands treated by bio-cementation methods typically exhibit an improvement in strength and stiffness, yet often with variable magnitudes, even at equal calcium carbonate contents. The variation in the mechanical performance of bio-cemented sands impedes the practical applications of MICP/ EICP, while it is poorly understood. In this presentation, we are going to understand the mechanical behaviour of bio-cemented sands, particularly the uncertainty or variation of the mechanical performance, from the microscopic point of view by using the discrete element method (DEM).