Analytical and Numerical Modeling for Rocking Impedance of a Single Pile in a Radially Inhomogeneous Viscoelastic Soil Medium

Evaluation of dynamic excitation response in the vicinity of the pile foundation is crucial in soil-pile interaction. In this paper, a new simplified analytical model is introduced to formulate the dynamic impedance of an inhomogenous visco-elastic soil layer having a monopile with a non-reflective boundary interface. The main idea of rocking (overturning) instability of the pile in a inhomogenous soil layer has been equated for the dynamic impedances (stiffness and damping) in a frequency domain. The model will develop a more understandable formulation to consider the relationship between impedance factors with different soil parameters like damping ratio, homogeneity and inhomogeneity of soil. The continuos and parabolic variation of these parameters across the boundary interface shows the model’s influence and suitability for practical use, since the mass of the inner boundary zone with a non-reflective interface has been considered here. On the basis of these variations, a series of predictions for the dynamic impedance, compatibility have been numerically varified using DynaN-3 as a main stream numerical platform. The numerical verification shows that the proposed analytical model has the potential to be used for pile design approach controlling the nonlinear behavior of pile-soil interface, especially predicting rocking impedance under dynamic loads in a viscoelastic soil medium.