Lateral Dynamics of a Pile in a Homogeneous Half-Space with Vlasov–Leont′ev Foundation Model and Expressions for a Rigid Disk

Abstract

This article demonstrates a new formulation for lateral dynamic stiffness of a pile floating in a homogeneous half-space. In the formulation, the soil domain adjacent to the pile is modeled as a three-dimensional continuum following the Vlasov–Leont′ev foundation model, while the soil domain below the pile-base is modeled by a spring–dashpot system. The spring–dashpot system is described using various expressions for an infinitesimal thick rigid massless disk on the surface of a homogeneous half-space for the swaying and rocking modes. These expressions are obtained from the literature and listed in the appendices. The objectives of the formulation are to investigate (1) whether the modeling approach generates accurate results and is representative of the results of a pile floating in a homogeneous half-space; (2) the range of applicability of the formulation approach; and (3) the best possible expression that can be used to describe the spring–dashpot system at the pile-base. From the comparative study and the parametric results, it is found, the present formulation approximately captures the mechanics of a pile floating in a homogeneous half-space and can be used for pile slenderness ratios less than or equal to 10 and those exhibiting nearly rigid or rigid behavior. Of all the expressions in appendices, the V–V expressions can be used to model the pile-base stiffness for a wide range of dimensionless frequency and Poisson’s ratio.