Condition assessment of composite structures using dynamic measurements

This paper is to present an overview for dynamic assessment of composite structures. The vibration based damage detection technique is classified into the global approach and the local damage indicator. The global approach included the direct comparison method and the finite element model updating technique. Local damage indicators include the relative difference of frequency response functions of the girder and the corresponding point on the slab, the correlation of frequency response functions, the wavelet packet energy rate index, the Kullback-Leibler spectral distance (KLD) and the wavelet based KLD. An experimental study has been carried out on a scale bridge model in the laboratory. Experimental results show that all damage indices are good indicators of the damage in the shear connection system and the finite element model updating is an effective method to identify the connection stiffness between the girder and slab