Effects of carbonate distribution pattern on the mechanical behaviour of bio-cemented sands: A DEM study

Microbially induced carbonate precipitation is a promising ground improvement technique which can enhance the mechanical properties of soils through calcium carbonate. Experimental evidences indicate that precipitated display different distribution patterns. Crystals develop at grain–grain contacts (contact cementing), connect soil grains were initially not in contact with each other (bridging), precipitate on grain surface (coating), or fill void space (pore filling). This paper investigates role aforementioned patterns behaviour lightly bio-cemented samples using discrete element modelling. Bio-cemented and contents are built, series drained triaxial compression simulations carried out confining pressures. The results show cementation form bridging cementing leads to obvious stiffness, strength dilatancy. In contrast, coating contributes only slightly improvement, pore filling exhibits negligible influence response material. findings suggest that, gain most effective way, treatments should be tailored crystals bridging.