Modelling of cutting tool - soil interaction - part II: macromechanical model and upscaling

In the foregoing paper we have proposed a strategy for soil modelling based on the discrete approach. By considering the soil as an assembly of rigid disks we have developed a local model. The model concentrates at the contact level between the disks the real mechanical behaviour of the soil. For this purpose suitable contact models have been developed, where specific elasto-plastic laws have been implemented in the node-to-segment contact formulation. In this second part after investigating the mechanical behaviour of the local model we reproduce, with an assembly of disks (global model), the real behaviour of stiff soils and rocks under standard loading paths. The change of scale from the local to global level is carried out through dimensional analysis. The behaviour of different soils is simulated by regular and irregular monodisperse packings of disks and compared with real laboratory tests.