Seismic Energy Dissipation, Self-Centering, and Settlement of Rocking Foundations: Analysis of Experimental Data with Comparisons to Numerical Modeling

Abstract

The major objective of this study is to correlate the rocking foundation performance parameters with their capacity parameters and earthquake demand parameters using the results obtained from 142 centrifuge and shaking table experiments. It is found that seismic energy dissipation and permanent settlement of rocking foundations correlate well with rocking coefficient and Arias intensity of the earthquake, whereas the maximum moment and peak rotation of the foundation correlate well with peak ground acceleration. A numerical model, using the contact interface model available in OpenSees, is developed to simulate the performance of rocking foundations, and it is validated using experimental results. Though the numerical model predicts the moment capacity, seismic energy dissipation, and tipping-over stability of rocking foundations reasonably well, the model appears to overpredict the settlement of foundations. Furthermore, a parametric study showed that settlement reduces as initial vertical stiffness increases and is directly proportional to peak ground displacement.