Hypoplastic particle finite element model for cutting tool-soil interaction simulations: Numerical analysis and experimental validation

• Published in: Underground space (Beijing) 2018-03, Vol.3 (1), p.61-71
• Main Authors: Leon Bal, Abdiel Ramon, Hoppe, Ulrich, Dang, Thai Son, Hackl, Klaus, Meschke, Günther
• Format: Article
• Language: English
• Subjects: Cutting tool-soil interaction; Excavation experiments; Hypoplasticity; Large deformations; Particle finite elements; Velocity-based finite elements formulation
• ISSN: 2467-9674; 2467-9674
• DOI: 10.1016/j.undsp.2018.01.008

This study presents numerical and experimental models for the analysis of the excavation of soft soils by means of a cutting tool. The computational model is constructed using an Updated Lagrangean (UL) velocity-based Finite Element approach. A hypoplastic formulation is employed to describe the constitutive behavior of soft soils. Large displacements and deformations of the ground resulting from the cutting tool-soil interaction are handled by means of the Particle Finite Element method, characterized by a global re-meshing strategy and a boundary identification procedure called α-shape technique. The capabilities and performance of the proposed model are demonstrated through comparative analyses between experiments and simulations of cutting tool-soft soil interactions. The experiments are performed using an excavation device at Ruhr-Universität Bochum (RUB), Germany. The main details concerning the setup and calibration and evolution of the measured draft forces are discussed. Selected computational results characterizing the cutting tool-soft soil interaction including the topology of the free surface, void ratio distribution ahead of the tool, spatio-temporal evolution of the reaction forces and abrasive wear behavior are evaluated.