DYNAMIC ANALYSIS OF GROUPED PILE FOUNDATION IN LAYERED SOILS

The dynamics of a grouped pile foundation in layered solis are investigated from the distributed parameter system modeling with a due consideration of the pile-soil-pile interaction. The substructure concept is applied to evaluate dynamic soil stiffness. The soil-pile coupling motion is solved for the base input through the eigenvalue decomposition and the transfer matrix method, deriving the pile head impedance function and the associated driving force (effective input). An efficient simplified mehod is also developed based on the “ring-pile” idea. From a numerical example, special remarks are given on the dynamic pile grouping effect.