Covariance Driven Subspace Identification Technique for Continuous Modal Parameters Identification of Sutong Bridge.

In order to allow a continuous online monitoring of modal frequencies and damping ratios, and to provide a good damage detection technique, covariance driven subspace identification (COSSI) technique with Empirical mode decomposition (EMD) as a filter for frequency decomposition and change for non-linear and non-stationary signals, is adopted for signal processing. This method provides advanced capabilities for modal parameter identification for continuous online modal parameter identification. Sutong Bridge, a long span cable stayed bridge is taken as a case study and the proposed method is applied. The results validates that the proposed method provides an accurate tracking of modal parameters such as damping coefficients and frequencies on continuous real life data.