Abstract: Offshore wind power is a deformation-sensitive structure,and the jacket foundation offshore wind power structure will bear large vertical cyclic loads during its service period. For analyzing and calculating the vertical load of the pile foundation,ABAQUS is used to analyze the influence zone of the pile tip. Based on the strain accumulation characteristics of sand in dynamic triaxial test,a novel Q-z model is proposed. Compared with traditional Q-z model,this novel model can use several parameters to simulate the behavior of displacement accumulating at the pile tip under axial cyclic loadings. Combined with the finite element software COMSOL,the secondary development is carried out to simulate the axial cyclic loading condition of single piles. The model validation is conducted with centrifuge tests of single pile under axial cyclic loadings. In the numerical simulation,the pile-soil interaction model（p-y） in the American Petroleum Institute（API）standard,the elastoplastic t-z model that considers the cyclic degradation of strength and stiffness in the pile-soil interface,and the novel Q-z model which can describe the pile tip accumulated displacement is adopted respectively to analyze the responses of offshore substation under cyclic loadings,which provide useful suggestions for the design of offshore substation.