Simulation of ground failure due to groundwater pumping.

Numerical modelling of failure generation due to groundwater pumping and prediction of fissure location, distribution, and geometry is a difficult task. To this aim we use a geomechanical model based on the structural equations of poroelasticity solved in a three-dimensional setting by the Finite Element (FE) – Interface Element (IE) approach. While standard FE are used to represent a continuum, IE prove especially suited to address the relative displacements of adjacent elements such as the opening and slippage of preexisting faults or the generation of new fractures. The IE allow for the modelling of fissure/fault mechanics using an elasto-plastic constitutive law based on the Mohr–Coulomb failure criterion. The corresponding FE-IE code is used for the prediction of localized differential subsidence and earth fissure activation/generation with some representative examples discussed in the literature.