A rational procedure to model the dynamic nonlinear soil structure interaction during pile vibratory driving is presented. The procedure is based on the analysis of the dynamic behavior of a cylinder embedded in a semi-infinite medium. Cylindrical shear waves that propagate away from the vibrated pile are evaluated using a one-dimensional radial discretization of the soil surrounding the pile. Degradation of the skin friction upon cyclic shear stress is evaluated by applying elements of earthquake engineering practice used to assess liquefaction potential. The friction ratio as measured in a CPT test, serves as a correlation parameter to present charts allowing one to estimate the soil degradation and excess pore-pressure buildup. A sample calculation illustrates the importance to account for soil cyclic degradation.