A simplified approach to the monopile-friction wheel dynamic interaction in composite foundation

This paper provides a simplified approach to investigate the monopile-wheel dynamic interaction of the composite foundation under work condition. Firstly, the reactions of saturated soil to the pile shaft caused by the vibration of pile are calculated by use of the plane strain model and three-dimensional continuum mechanics theory. Then, the hydrodynamic pressure around the composite foundation and pile governing equations are described by the radiation wave theory and Timoshenko beam theory, respectively. After verifying rationality and accuracy of the proposed solutions, a comprehensive analysis is performed on the diameter and thickness of wheel foundation affecting the horizontal displacement and bending moment along the composite foundation and the displacement field of soil. The main results show that the maximum and minimum of the bending moment and horizontal displacement of the piled foundation decrease with the increase of the wheel dimension, but their distribution law varying with the depth and frequency remains unchanged. Therefore, monopile with smaller diameter or length is preferred in the proposed foundation for balancing the high bearing capacity and economical cost. Finally, some valuable recommendations are also provided for the design guidelines of this innovative foundation employed in marine area.