Research On Damage Recognition Of Advanced Grid Stiffened Structure

Advanced Grid Stiffened Structure (AGS) has received great attention in aviation aerospace field because of its unique advantages. After more than ten years of research, scholars have made great contribution on mechanics properties, analysis methods, fabrication methods et al. And there still need more on the damage mechanism, damage detection and health monitoring.In this paper, by the study of damage detection methods which applied on engineering structures, we made an exploratory research on the damage recognition of the AGS structure through neural network and mode curvature difference. The main works of this paper are as follows:First, we made a research on the building of equivalent stiffness model of the AGS structure, and compared this equivalent model with the finite element model. On the basis, with the previous research, we made a preliminary study on the damage recognition of the AGS structure by PNN neural network. Then, summarized the theories of the mode curvature difference, and the FEM modal was introduced to prove the effectiveness of the damage recognition of the AGS structure by using this method. And at last, this method was also validated by the modal experiment.There still need a further research on the recognition of damage types and the degrees,as this paper only researched the damage location of the AGS structure.