A macro-element for the modelling of shallow foundation deformations under seismic load

This paper presents a new soil-foundation macro-element model to allow efficient and sufficiently accurate consideration of soil-foundation-structure interaction in structural analysis. The model makes use of two constitutive models, a plasticity model which models the soil inelastic deformation, and an elastic uplift model, which captures the geometric non-linearity during uplift of the foundation. Further considerations are made to allow the macro-element to be efficiently implemented in a particular non-linear finite element software (Ruaumoko3D). Two experimental centrifuge tests are simulated using the proposed macro-element: one of a bridge pier and one of a one-bay, one-storey frame structure. The simulated results are compared to the experimental behaviour to demonstrate the accuracy of the numerical model.