Performance analysis of various numerical methods for predicting monopile response under machine induced vibration

Abstract

In this study, we verify the accuracy of the results obtained using two different numerical methods to simulate a pile-supported machine foundation under vertical vibration. To achieve this, finite element and finite difference methods, available as PLAXIS 3D and FLAC 3D, respectively, are selected for the study. A model consisting of a monopile with a diameter of 0.166 m and a length of 5.8 m is modelled to support the vibratory load induced by the rotary machine. A linear elastic model is used for the pile material and Mohr-Coulomb failure criterion is used for the soil. An analysis is performed to determine the frequency-versus-amplitude response of the monopile subjected to rotary-machine-induced vertical vibrations with different dynamic load intensities (0.735, 1.448, 2.117, and 2.721 Nm). The results obtained from both numerical analyses are compared with the experimental results available in the literature. Both numerical methods effectively simulate the nonlinear behavior of the soil-pile system, as observed in the experimental results. Based on the results, it is deduced that the finite element method simulated more harmonious results than the finite difference method compared with the experimental results, with more computational efficiency.