  Soft or weakly-consolidated sand refers to porous materials composed of
particles (or grains) weakly held together to form a solid but that can be
easily broken when subjected to stress. These materials do not behave as
conventional brittle, linear elastic materials and the transition between these
two regimes cannot usually be described using poro-elastic models. Furthermore,
conventional geotechnical sampling techniques often result in the destruction
of the cementation and recovery of sufficient intact core is, therefore,
difficult. This paper studies a numerical model that allows us to introduce
weak consolidation in granular packs. The model, based on the LIGGGHTS open
source project, simply adds an attractive contribution to particles in contact.
This simple model allow us to reproduce key elements of the behaviour of the
stress observed in compacted sands and clay, as well as in poorly consolidated
sandstones. The paper finishes by inspecting the effect of different
consolidation levels in fluid-driven fracture behaviour. Numerical results are
compared against experimental results on bio-cemented sandstones.
