Damage Detection Methods Based on the Susceptibility of the Damage Mode Shapes

Importance of having the ability to monitor structural health and detect damage in the fastest possible time is one of the main concerns of engineers, particularly in fields of mechanic and aerospace. This importance is due to damage in a structure during work can be very severe and sometimes irreparable damages to be followed. The diagnostic methods based on vibration characteristics of structures has been cover the problems of other methods completely. The purpose of this study detect of damage in composite shells with use located sensitivity methods based on mode shape and susceptibility to different intensities of damage in a composite cylindrical shell. Results of this study show that only in the third step of damage that more than 0.077% of the total area of the structural will be able to identify and this research illustrates the precision of the method and limits that can use of it. This method cannot distinguish the imperfections in first and second steps that have 0.02% and 0.043% of the total area of composite cylindrical shell but the method of (MSCS) suitable in the second and third steps of damage and so the third method (DI) suitable for detect in the first steps of damage to third step also method detects damage in very small, about 0.02% area of the cylindrical shell composite structures. According to results of this paper we can conclude that used method for damage detection in this paper is a successful method and can be used in mechanical projects.