Adhesive Contact Algorithm for MPM and its Application to the Simulation of Cone Penetration in Clay

Contact between bodies is one of the most challenging problems to solve, especially when combined with large deformations. For MPM, several methods have been developed to simulate frictional contact, i.e. shear stress is proportional to the normal stress via a friction coefficient; however, for cohesive soils under undrained conditions the interface shear stress is more likely a function of the undrained shear strength and independent of the normal stress (adhesive contact). This paper presents the extension of one of the most widely used contact algorithms in MPM for adhesive contact. This enhanced formulation is validated with a sliding block benchmark and applied to the simulation of cone penetration testing (CPT) in clay. CPT is an in situ test commonly used in geoengineering to determine the subsoil's stratigraphy and to estimate soil parameters. It is shown that the adhesion at the cone-soil interface affects significantly the measured cone resistance. Numerical results are compared with available analytical and experimental studies, showing the effectiveness of the proposed method to describe undrained penetration in clay.