FRF Frequency Characteristic Analysis about Damaged Crossbeam

In this paper the Frequency Response Function of a damaged crossbeam has been researched. At first the state of crossbeam bending stiffness changed depend on its damaged degree has been research, base on this work the relationship between the Frequency Response Function and the crossbeam damage degree has been founded. We can find two demonstrative characters associated with crossbeam damage degree. One of characters is the peak values of Frequency Response Function offset depend on crossbeam damage degree. Another character is the stiffness reducing could divide single peak of Frequency Response Function into several peaks. The number of peaks on Frequency Response Function depends on crossbeam damaged degree. Comparing the result of calculate with experimental result has been done in the paper. The experimental result approach to calculative result well. This research is helpful in crossbeam damage diagnose on line.