Biostimulated ground improvement

Recently several in situ techniques are being developed to change the mechanical properties of soils by stimulating biochemical processes. A procedure named Biogrout is developed to increase strength and stiffness of unconsolidated sands, based on microbial-induced carbonate precipitation. Recently, this development resulted in a field scale experiment in which 40m3 of sand was cemented within 12 days, reaching average unconfined compressive strengths of 2 MPa with limited reduction in permeability. Pilot projects are in preparation. In order to optimize this process, the use of waste streams as substrate for biocementation has been investigated.