Generalized dynamic Winkler model for nonlinear soil-structure interaction analysis

The beam on nonlinear Winkler foundation (BNWF) model is widely used in soil-structure interaction (SSI) analysis owing to its relative simplicity. This paper focuses on the development of a versatile dynamic BNWF model for the analysis of shallow and deep foundations. The model is developed as a stand-alone module to be incorporated in commercial nonlinear structural analysis software. The features of the model discussed are the loading and unloading rules, slack zone development, the modeling of cyclic degradation and radiation damping. The model is shown to be capable of representing various response features observed in SSI experiments. In addition, the predictions of the model for centrifuge tests of piles in weakening and partially weakening soil are shown to be in good agreement with the experimental results. This agreement demonstrates the potential of the model as a useful tool for design engineers involved in seismic design, especially performance-based design.