A Coupled Discrete–Finite Element Method for the Ice-Induced Vibrations of a Conical Jacket Platform with a GPU-Based Parallel Algorithm

Abstract

Flowing ice draws special attention due to the dynamic response of jacket platforms. In this study, a coupled discrete element method (DEM) and finite element method (FEM) are developed to analyze the interaction between sea ice and conical jacket platforms to determine the ice-induced vibrations (IIVs) of the structure. To model the ice cover and to investigate ice loads, a DEM with bond-breaking spherical elements is adopted. Meanwhile, the FEM (with a beam element) is applied to model the IIVs of the jacket platform. An efficient transmission scheme between the bond-breaking spherical elements and the beam element is proposed. The graphics processing unit-based parallel algorithm is developed to improve the computational efficiency. The simulated ice loads are verified by comparing them with the full-scale data and different ice load functions. The simulated IIV accelerations of the JZ20-2 MUQ conical platform in the Bohai Sea (China) are consistent with the full-scale data under various ice conditions (e.g., velocity and thickness). The numerical results show that the IIV acceleration increases linearly with the ice velocity and the square of the ice thickness.