Parameter sensitivity study of dynamic response for jack-ups by FEM analysis

•A series of static analysis, modal analysis, and transient analysis were performed for a FEM jack-up model.•The interaction of fluid–structure–soil was considered.•FEM analysis results of parameter sensitivity provided references for the design of jack-ups.

Jack-up platforms will generally behave as highly dynamic systems because of the structure flexibility. The environmental forces acting on these jack-ups will therefore induce significant dynamic response. In this paper, based on ANSYS, the three-dimensional model of a truss leg jack-up was built. With interaction of fluid–structure–soil being considered, a series of static analysis, modal analysis, and transient analysis were performed for the model with different dimensional or load parameters; and the dynamic magnification factors were calculated. Sensitivity of these parameters on the dynamic response of jack-ups were discussed in detail.