A Coupled Micro-Macro Method for Pile Penetration Analysis

This paper presents a coupled macro-micro method for numerically simulating pile penetration. In order to properly describe a set of particles experiencing large deformation, during the penetration process, Particle Flow Code (PFC), which is based on discrete element method, is introduced here to simulate sands near the pile as interacted balls. Thus the discrete properties of the sands nearly around the pile can well be depicted. In order to overcome the deficiency of particles during the simulation process, the domain containing particles away from the pile is simulated as continuous media by FLAC program, given that this set of particles exhibits linear elastic properties. Thus all the sands around the pile are divided into two domains, and the interface between them is treated as force boundary for the continuous domain and velocity boundary for the other domain simulated as a set of balls. It is shown that the coupled method can well depict the pile penetration process without loosing the discrete properties of the sands near the pile and efficiently reduce particle numbers during the simulation.