Effect of damage on the modal parameters of a cylindrical shell

摘要

The objective of the study was to investigate the feasibility of assessing damage to structural systems by measuring the changes in the dynamic characteristics of a thin circular cylindrical shell with both ends open. Theoretical and experimental modal analyses were performed for the shell. Subsequently, a notch was machined into the shell simulating a small amount of damage. The shell with the notch was again subjected to experimental modal analysis. A comparison of the modal parameters determined from the tests before and after the shell was damaged showed that the natural frequencies were not sensitive to the crack introduced. However, some of the mode shapes showed significant changes, establishing that the mode shapes were the more sensitive parameters for damage detection.