DYNAMICS OF SHOCK WAVE MOTION DURING PILE HAMMERING - A COMPARATIVE STUDY OF CONTINUOUS AND DISCRETE MODELLING APPROACHES

摘要

In hammering steel or concrete piles a transient shock wave motion is generated in order to win the resisting effects of skin friction and point load. Conventional way to simulate wave motion in pile is to replace the pile by an assembly of axially elastic rod elements. As an alternative way the wave propagation problem may be solved in terms of classical semidefinite eigenfunctions of axially elastic rod producing small and decoupled ODE system with respect to the modal coordinates. A systematic analysis has been carried out and reported to evaluate the computational costs and accuracy reached by continuous and discrete methods in long term simulations for varying number of modal coordinates and nodal variables.