Research on Damage Assessment Method Using Weighting Modal Information

Many damage detection methods based on the modes and their evolution can be achieved with high accuracy by numerical examples without noise. However, a certain level of noise always exists in practical measurement which has a great effect on the identification. In view of this situation, a robust damage assessment method based on weighting modal information for nondestructive detection in beams is presented in this paper. In the process of damage detecting and locating, displacement mode as the basic parameter is weighted and optimized to ensure its accuracy. Meanwhile, the relation between the damage positions and different order model of vibration is considered to improve the capability of damage identification. Numerical examples of single and multi-damaged simply-supported beams are performed using first five modes which can be measured easily. The results show that the proposed method works well for the damage detection and the assessments are in good agreement with the actual condition even with 5% of random noise being added to the simulations. Finally, experimental examples of pipeline structures in different damaged cases were provided to verify the correctness and feasibility of the proposed method through approach of experimental model, which may provide inspiration for further engineering application.