Parametric studies of pile-supported protective structures subjected to barge impact using simplified models

Independent protective structures supported by concrete-filled steel pipes have been widely used to protect bridge piers from vessel impact. In a high-energy impact scenario, such protective structures can absorb a large amount of energy through plastic deformation. Many previous studies are based on empirical static analysis which ignores important dynamic effects involved in an impact event. Finite-element simulation serves as an alternative approach which is commonly used for dynamic analysis of vessel collisions. However, finite-element simulation is expensive regarding both calculation time and computing resources. To conquer these problems, a simplified impact model considering soil-pile interactions and geometric non-linearity is developed in this paper based on the coupled multi-degree-of-freedom model previously proposed by the authors. The computational cost can be remarkably reduced by the simplified models. The influences of pile cross-section diameter, pipe thickness, pile length, free span of pile and soil properties on the energy dissipation capacity of pile-supported protective structures are investigated in this paper using the simplified models.