Vibration analysis Of composite beam with crack

Abstract

Composite beams and beam like elements are principal constituents of many structures and used widely in high speed machinery, aircraft and light weight structures. Crack is a damage that often occurs on members of structures and may cause serious failure of the structures. The influence of cracks on dynamic characteristics like natural frequencies, modes of vibration of structures has been the subject of many investigations. However, the parametric studies like effect of geometry, crack location and support conditions on natural frequencies of composite beam are scarce in literature. In the present work, a numerical study using finite element is performed to investigate the free vibration response of composite beams. The finite element software ANSYS is used to simulate the free vibrations. A variety of parametric studies are carried out to see the effects of various changes in the laminate parameters on the natural frequencies. The parameters investigated include the effects of fiber orientation, the location of cracks relative to the restricted end, depth of cracks, volume fraction of fibers, length of beam and support conditions. The study shows that the highest difference in frequencies occur when the value of the fiber orientation equal to zero degree. The increase of the beam length results in a decrease in the natural frequencies of the composite beam and also shows that an increase of the depth of the cracks leads to a decrease in the values of natural frequencies.