Identification of existing structures under uncertainty

A finite element-based element-level time-domain system identification procedure is proposed to estimate the stiffness and damping coefficients of a large existing linear shear-type building excited by an unknown input. The procedure does not need any information on the input excitation forces. The method is verified by using numerical examples. For verification purposes, both the noise-free and noise-included output responses are considered. In all cases, the proposed method identified the structural parameters very well. The identification of a large structural system using only noise-contaminated output responses is emphasized