The lateral bearing capacity of the pile foundation of offshore wind turbine degrades due to the long-period cyclic lateral load. For the lateral loaded pile in undrained soft caly

a degradation model based on accumulated plastic strain is adopted to model the cyclic degradation of the undrained soil strength. Then a series of two-dimensional finite element simulations are carried out; and a simplified p-y curve method is presented to analyze the degradation of the lateral bearing capacity of a cyclically laterally loaded single pile. For the case of small cycle numbers

the results of the finite element simulations are consistant well with that of the simplified method. Based on this cognition

an attenuation law of the lateral bearing capacity of a pile subjected to long-period a large amount cyclic lateral load is obtained using the two-dimensional simplified method. It is found that

for the ratio of the cyclic lateral load to the initial lateral pile bearing capacity smaller than the reverse of soil sensitivity

although the lateral bearing capacity of cyclic lateral loaded pile degrades

the pile still remains in stable state without failure.