Numerical Analysis of the Interference of Two Active Machine Foundations

This study examines the influence of the interference on the dynamic response of two active machine foundations using the finite element analysis. The finite element model has been built carefully to ensure that the finite element model extend, and the mesh size do not influence the obtained results. Furthermore, the methodology of the finite element analysis has been verified using well-known and robust analytical solutions of wave propagation and machine vibration. Loose sand, medium sand, and dense sand and a vibration frequency range of 0.5–20.0 Hz have been considered in the analyses. The results showed that the interference of two active machine foundations remarkably increases the dynamic settlement with a percentage increase range from 1 to 77%. This percentage increase declines as the frequency of vibration or the distance between the foundations increases and rises as the soil stiffness increases. It was also found that the critical distance after which the interference effect terminates depends on the frequency of vibration and the stiffness of the soil, where the critical distance increases as the frequency of vibration declines or as the stiffness of the soil increases. Finally, a methodology has been proposed based on the results of the analyses to implicate the effect of interference in the calculation of the dynamic settlement.