Model-updating with experimental frequency response function considering general damping

Abstract

In order to obtain a more accurate finite element model of a constructed structure, a new frequency response function–based model-updating approach is proposed. A general viscous damping model is assumed in this approach for better simulating the actual structure. The approach is formulated as an optimization problem which intends to minimize the difference between analytical and experimental frequency response functions. Neither dynamic expansion nor model reduction is needed when not all degrees of freedom are measured. State-of-the-art optimization algorithms are utilized for solving the non-convex optimization problem. The effectiveness of the presented frequency response function model-updating approach is validated through a laboratory experiment on a four-story shear-frame structure. To obtain the experimental frequency response functions, a shake table test was conducted. The proposed frequency response function model-updating approach is shown to successfully update the stiffness, mass, and damping parameters in matching the analytical frequency response functions with the experimental frequency response functions. In addition, the updating results are also verified by comparing time-domain experimental responses with the simulated responses from the updated model.