Philippe Pierre

The action of a fluid flow on a granular material is a common situation in nature and in many industrial processes. Numerous studies, based on both experiments and modelling, have led to a better understanding and description of the fluid-granular interaction in situations such as surface erosion or fluidization. The hydro-mechanical behaviour of cemented soils, and more particularly of cemented granular soils, remains less known although this type of material is also frequently encountered in sedimentary rocks (sandstones, conglomerates, breccia…) or engineering materials (mortars, concrete, asphalt…).
To address this problem, we consider here more specifically grains that are artificially cemented by creating, from an external solid phase, adhesive bridges whose tensile strength can be varied. This allows a gradual transition from the pure granular case to weakly cemented ones. In this presentation, I will report some recent studies carried out for various situations, such as impinging jet erosion, surface erosion, localized injection, with, almost systematically, an approach combining and comparing experiments on model systems with numerical simulations involving coupled Lattice Boltzmann (LBM) and Discrete Elements (DEM) methods.