Effects of Soil-Structure Interaction on Torsionally Coupled Base Isolated Machine Foundation under Earthquake Load

In this paper, the influence of soil-structure interaction (SSI) on a torsionally coupled turbo-generator (TG) machine foundation is studied under earthquake ground motions. The beneficial effects base isolators in TG motions are also duly, considering SSI. A typical analyzed using three-dimensional finite element (FE) model. Two superstructure eccentricity ratios considered to represent torsional coupling. Soft soil properties study This research concludes that coupling alter natural frequencies, if ignored, could lead unsafe design. deck accelerations and displacements increased with an increase eccentricity. On other hand, greatly reduced help isolators, thus confirming use foundations protect sensitive equipment from strong However, SSI reduce frequencies resting soft conditions activate higher mode participation, resulting amplifying response.