A Nonlinear Model Inversion to Estimate Dynamic Soil Stiffness of Building Structures

This study presents an output-only model inversion method to jointly estimate the model parameters and foundation input motions in structural models. The model inversion is based on Bayesian finite element model updating using the measured seismic response of the structure. The model parameters to be estimated consist of parameters characterizing the structural model, dynamic soil springs (to account for inertial soil structure interaction effects), and Rayleigh damping. We use the recorded response of the Millikan Library building to the 2002 Yorba Linda earthquake for validation study, in which the recorded structural responses are used to update the structural model resting on soil springs and dashpots. This study is a step forward towards developing model inversion methods that can be used with seismic response of real-world buildings to identify the Rayleigh damping and dynamic soil springs parameters.