Abstract：The beam-on-dynamic-Winkler-foundation (BDWF) model is utilized to determine the horizontal dynamic response of a single pile in double-layer viscoelastic soils. Based on frequency-dependent ‘springs’ and ‘dashpots’，the pile is modeled as a Timoshenko beam considering both bending and shearing and a more rigorous analytical solution of horizontal vibration for a single pile is developed. On the basis of the solution developed here，the influence of many parameters on the dynamic response of pile，such as the ratio of the Young’s modulus of the pile to that of the soil，the ratio of pile length to its diameter，the variation of soil properties and the frequency，is studied. Furthermore，a comparison is also made between the theory here and that based on Euler beam model in two-layered soils. It is found that the theory based on Euler beam gives more errors without considering the parameters given here. Thus，in the analysis on horizontal vibration of pile in layered soils，the more rigorous theory presented herein should be used，otherwise more errors can be brought forward to the analysis result.
