Pile field numerical analysis at the stage of dynamic impacts

Abstract

The authors propose a combined approach for definition of the shear rigidity of the multilayered soil which is cut through by a pile. The static solution for the vertical direction is presented in the view of an axisymmetric problem. As to the horizontal direction, the solution is presented in view of a beam on elastic subsoil with genetically non-linear transition to equivalent horizontal dynamic rigidity of the wide pile field. At the stage of formation of the stress-strain state of the system under the main combination of static loads еhe axisymmetric solution provides visual clarity in the analysis of the stress-strain state of the pile and near-pile soil in comparison with the approved analytical methods. The horizontal rigidity is considered as for a discrete single bent pile in the medium of an elastic layered half-space. These methods of numerical modeling of deformations of a single pile make it possible to expand the algorithm of analytical calculation of a large pile field, which in turn is modified by the authors by excluding deformations of the pile body due to its natural consideration in the finite element formulation, as well as by the parameter of the limiting radius of the influence of a single pile on the settlement of neighboring piles. In this publication, the authors describe a methodological approach to constructing a model of a large-size pile field at the second stage of short-term or special dynamic impacts. A transition to the integral rigidity of pile groups is proposed, taking into account the spatial dynamic model of a large-size pile foundation. The numerical problems of modeling a spatial soil array, a wave method for determining the discreteness of the model, methods for replacing the underlying half-space with a contact model are considered.