AN EXPERIMENTAL INVESTIGATION ON DYNAMIC BEHAVIOR ON THIN CYLINDRICAL SHELLS WITH CRACKS

The holographic vibration patterns of thin cylindrical shells with axial cracks or circular cracks are obtained separately with a time-average method and a vibration pattern is divided into three parts: a partial vibration area around the crack, the original vibration area of the thin cylindrical shell and the transition area to analyze the effect of cracks on vibration patterns and natural frequencies of thin cylindrical shells in this paper. The partial vibra-tion is mainly studied, the conclusions obtained are that the partial vibration has its own vibration pat-terns and natural frequencies, so the complex vi-bration patterns and abnormal changes of natural frequencies of thin cylindrical shells with cracks can be explained very well.