Estimation of modal parameters and their uncertainty bounds from subspace-based system identification
Abstract
Operational Modal Analysis of existing structures is performed using output only vibration measurements. To evaluate the quality of the resulting modal parameters (natural frequencies, damping ratios, mode shapes) from system identification it is essential to know their statistical uncertainty content. An innovative and efficient algorithm to estimate the modal parameters and their uncertainties from subspace-based system identification has been developed. Applications to output only measurements have been demonstrated on the S101 Bridge case.