2021 Volume 21 Issue 3 Pages 3_1-3_15
A method is proposed to identify the story stiffness matrix of torsionally coupled shear buildings story by story, using the modal parameters extracted from Green's functions. Numerical tests reveal that although the method is valid, robustness to noise is low. In particular, the stiffnesses of the top story are greatly underestimated due to non-cancellation of noise, indicating that noise-reduced modal parameters are of importance for identification. An application of the method to an existing building reveals that knowledge of the precise masses and moments of inertia of individual floors is required in advance, and that velocity recordings and their decomposition into three degrees of freedom using a precise location of the center of gravity may reduce noise of the modal parameters.
