Abstract:Based on wavelet packet analysis and wavelet packet energy, the sum square of the wavelet packet energy change rate (WPERSS) damage index is proposed. The wavelet packet is applied to extract the damage index from both healthy and damaged structures for damage detection. A simply supported beam example is simulated in different damage and noise conditions. In addition, a double pylon cablea2stayed bridge model is tested in three damage conditions. The results are analyzed and prove the effectiveness of the WPERSS damage index.